Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* i2c-core.c - a device driver for the iic-bus interface */ |
| 2 | /* ------------------------------------------------------------------------- */ |
| 3 | /* Copyright (C) 1995-99 Simon G. Vogl |
| 4 | |
| 5 | This program is free software; you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation; either version 2 of the License, or |
| 8 | (at your option) any later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU General Public License |
| 16 | along with this program; if not, write to the Free Software |
| 17 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ |
| 18 | /* ------------------------------------------------------------------------- */ |
| 19 | |
Jan Engelhardt | 96de0e2 | 2007-10-19 23:21:04 +0200 | [diff] [blame] | 20 | /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl> |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 22 | SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and |
Michael Lawnick | 0826374 | 2010-08-11 18:21:02 +0200 | [diff] [blame] | 23 | Jean Delvare <khali@linux-fr.org> |
| 24 | Mux support by Rodolfo Giometti <giometti@enneenne.com> and |
| 25 | Michael Lawnick <michael.lawnick.ext@nsn.com> */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | #include <linux/module.h> |
| 28 | #include <linux/kernel.h> |
| 29 | #include <linux/errno.h> |
| 30 | #include <linux/slab.h> |
| 31 | #include <linux/i2c.h> |
| 32 | #include <linux/init.h> |
| 33 | #include <linux/idr.h> |
Arjan van de Ven | b3585e4 | 2006-01-11 10:50:26 +0100 | [diff] [blame] | 34 | #include <linux/mutex.h> |
Grant Likely | 959e85f | 2010-06-08 07:48:19 -0600 | [diff] [blame] | 35 | #include <linux/of_device.h> |
Jean Delvare | b8d6f45 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 36 | #include <linux/completion.h> |
Mike Rapoport | cea443a | 2008-01-27 18:14:50 +0100 | [diff] [blame] | 37 | #include <linux/hardirq.h> |
| 38 | #include <linux/irqflags.h> |
Rodolfo Giometti | f18c41d | 2009-06-19 16:58:20 +0200 | [diff] [blame] | 39 | #include <linux/rwsem.h> |
Mark Brown | 6de468a | 2010-03-02 12:23:46 +0100 | [diff] [blame] | 40 | #include <linux/pm_runtime.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | #include <asm/uaccess.h> |
| 42 | |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 43 | #include "i2c-core.h" |
| 44 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 45 | |
Jean Delvare | 6629dcf | 2010-05-04 11:09:28 +0200 | [diff] [blame] | 46 | /* core_lock protects i2c_adapter_idr, and guarantees |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 47 | that device detection, deletion of detected devices, and attach_adapter |
| 48 | and detach_adapter calls are serialized */ |
Jean Delvare | caada32 | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 49 | static DEFINE_MUTEX(core_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | static DEFINE_IDR(i2c_adapter_idr); |
| 51 | |
Jean Delvare | 4f8cf82 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 52 | static struct device_type i2c_client_type; |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 53 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver); |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 54 | |
| 55 | /* ------------------------------------------------------------------------- */ |
| 56 | |
Jean Delvare | d2653e9 | 2008-04-29 23:11:39 +0200 | [diff] [blame] | 57 | static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, |
| 58 | const struct i2c_client *client) |
| 59 | { |
| 60 | while (id->name[0]) { |
| 61 | if (strcmp(client->name, id->name) == 0) |
| 62 | return id; |
| 63 | id++; |
| 64 | } |
| 65 | return NULL; |
| 66 | } |
| 67 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | static int i2c_device_match(struct device *dev, struct device_driver *drv) |
| 69 | { |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 70 | struct i2c_client *client = i2c_verify_client(dev); |
| 71 | struct i2c_driver *driver; |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 72 | |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 73 | if (!client) |
| 74 | return 0; |
| 75 | |
Grant Likely | 959e85f | 2010-06-08 07:48:19 -0600 | [diff] [blame] | 76 | /* Attempt an OF style match */ |
| 77 | if (of_driver_match_device(dev, drv)) |
| 78 | return 1; |
| 79 | |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 80 | driver = to_i2c_driver(drv); |
Jean Delvare | d2653e9 | 2008-04-29 23:11:39 +0200 | [diff] [blame] | 81 | /* match on an id table if there is one */ |
| 82 | if (driver->id_table) |
| 83 | return i2c_match_id(driver->id_table, client) != NULL; |
| 84 | |
Jean Delvare | eb8a790 | 2008-05-18 20:49:41 +0200 | [diff] [blame] | 85 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 86 | } |
| 87 | |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 88 | #ifdef CONFIG_HOTPLUG |
| 89 | |
| 90 | /* uevent helps with hotplug: modprobe -q $(MODALIAS) */ |
Kay Sievers | 7eff2e7 | 2007-08-14 15:15:12 +0200 | [diff] [blame] | 91 | static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 92 | { |
| 93 | struct i2c_client *client = to_i2c_client(dev); |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 94 | |
Jean Delvare | eb8a790 | 2008-05-18 20:49:41 +0200 | [diff] [blame] | 95 | if (add_uevent_var(env, "MODALIAS=%s%s", |
| 96 | I2C_MODULE_PREFIX, client->name)) |
| 97 | return -ENOMEM; |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 98 | dev_dbg(dev, "uevent\n"); |
| 99 | return 0; |
| 100 | } |
| 101 | |
| 102 | #else |
| 103 | #define i2c_device_uevent NULL |
| 104 | #endif /* CONFIG_HOTPLUG */ |
| 105 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | static int i2c_device_probe(struct device *dev) |
| 107 | { |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 108 | struct i2c_client *client = i2c_verify_client(dev); |
| 109 | struct i2c_driver *driver; |
Hans Verkuil | 50c3304 | 2008-03-12 14:15:00 +0100 | [diff] [blame] | 110 | int status; |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 111 | |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 112 | if (!client) |
| 113 | return 0; |
| 114 | |
| 115 | driver = to_i2c_driver(dev->driver); |
Jean Delvare | e045744 | 2008-07-14 22:38:30 +0200 | [diff] [blame] | 116 | if (!driver->probe || !driver->id_table) |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 117 | return -ENODEV; |
| 118 | client->driver = driver; |
Marc Pignat | ee35425 | 2008-08-28 08:33:22 +0200 | [diff] [blame] | 119 | if (!device_can_wakeup(&client->dev)) |
| 120 | device_init_wakeup(&client->dev, |
| 121 | client->flags & I2C_CLIENT_WAKE); |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 122 | dev_dbg(dev, "probe\n"); |
Jean Delvare | d2653e9 | 2008-04-29 23:11:39 +0200 | [diff] [blame] | 123 | |
Jean Delvare | e045744 | 2008-07-14 22:38:30 +0200 | [diff] [blame] | 124 | status = driver->probe(client, i2c_match_id(driver->id_table, client)); |
Wolfram Sang | e4a7b9b | 2010-05-04 11:09:27 +0200 | [diff] [blame] | 125 | if (status) { |
Hans Verkuil | 50c3304 | 2008-03-12 14:15:00 +0100 | [diff] [blame] | 126 | client->driver = NULL; |
Wolfram Sang | e4a7b9b | 2010-05-04 11:09:27 +0200 | [diff] [blame] | 127 | i2c_set_clientdata(client, NULL); |
| 128 | } |
Hans Verkuil | 50c3304 | 2008-03-12 14:15:00 +0100 | [diff] [blame] | 129 | return status; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | } |
| 131 | |
| 132 | static int i2c_device_remove(struct device *dev) |
| 133 | { |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 134 | struct i2c_client *client = i2c_verify_client(dev); |
David Brownell | a1d9e6e | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 135 | struct i2c_driver *driver; |
| 136 | int status; |
| 137 | |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 138 | if (!client || !dev->driver) |
David Brownell | a1d9e6e | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 139 | return 0; |
| 140 | |
| 141 | driver = to_i2c_driver(dev->driver); |
| 142 | if (driver->remove) { |
| 143 | dev_dbg(dev, "remove\n"); |
| 144 | status = driver->remove(client); |
| 145 | } else { |
| 146 | dev->driver = NULL; |
| 147 | status = 0; |
| 148 | } |
Wolfram Sang | e4a7b9b | 2010-05-04 11:09:27 +0200 | [diff] [blame] | 149 | if (status == 0) { |
David Brownell | a1d9e6e | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 150 | client->driver = NULL; |
Wolfram Sang | e4a7b9b | 2010-05-04 11:09:27 +0200 | [diff] [blame] | 151 | i2c_set_clientdata(client, NULL); |
| 152 | } |
David Brownell | a1d9e6e | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 153 | return status; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | } |
| 155 | |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 156 | static void i2c_device_shutdown(struct device *dev) |
| 157 | { |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 158 | struct i2c_client *client = i2c_verify_client(dev); |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 159 | struct i2c_driver *driver; |
| 160 | |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 161 | if (!client || !dev->driver) |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 162 | return; |
| 163 | driver = to_i2c_driver(dev->driver); |
| 164 | if (driver->shutdown) |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 165 | driver->shutdown(client); |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 166 | } |
| 167 | |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 168 | #ifdef CONFIG_PM_SLEEP |
| 169 | static int i2c_legacy_suspend(struct device *dev, pm_message_t mesg) |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 170 | { |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 171 | struct i2c_client *client = i2c_verify_client(dev); |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 172 | struct i2c_driver *driver; |
| 173 | |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 174 | if (!client || !dev->driver) |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 175 | return 0; |
| 176 | driver = to_i2c_driver(dev->driver); |
| 177 | if (!driver->suspend) |
| 178 | return 0; |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 179 | return driver->suspend(client, mesg); |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 180 | } |
| 181 | |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 182 | static int i2c_legacy_resume(struct device *dev) |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 183 | { |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 184 | struct i2c_client *client = i2c_verify_client(dev); |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 185 | struct i2c_driver *driver; |
| 186 | |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 187 | if (!client || !dev->driver) |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 188 | return 0; |
| 189 | driver = to_i2c_driver(dev->driver); |
| 190 | if (!driver->resume) |
| 191 | return 0; |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 192 | return driver->resume(client); |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 193 | } |
| 194 | |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 195 | static int i2c_device_pm_suspend(struct device *dev) |
| 196 | { |
| 197 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 198 | |
Mark Brown | d529de2 | 2011-01-14 22:03:49 +0100 | [diff] [blame] | 199 | if (pm) |
| 200 | return pm_generic_suspend(dev); |
| 201 | else |
| 202 | return i2c_legacy_suspend(dev, PMSG_SUSPEND); |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 203 | } |
| 204 | |
| 205 | static int i2c_device_pm_resume(struct device *dev) |
| 206 | { |
| 207 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 208 | |
| 209 | if (pm) |
Mark Brown | d529de2 | 2011-01-14 22:03:49 +0100 | [diff] [blame] | 210 | return pm_generic_resume(dev); |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 211 | else |
Mark Brown | d529de2 | 2011-01-14 22:03:49 +0100 | [diff] [blame] | 212 | return i2c_legacy_resume(dev); |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 213 | } |
| 214 | |
| 215 | static int i2c_device_pm_freeze(struct device *dev) |
| 216 | { |
| 217 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 218 | |
Mark Brown | d529de2 | 2011-01-14 22:03:49 +0100 | [diff] [blame] | 219 | if (pm) |
| 220 | return pm_generic_freeze(dev); |
| 221 | else |
| 222 | return i2c_legacy_suspend(dev, PMSG_FREEZE); |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 223 | } |
| 224 | |
| 225 | static int i2c_device_pm_thaw(struct device *dev) |
| 226 | { |
| 227 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 228 | |
Mark Brown | d529de2 | 2011-01-14 22:03:49 +0100 | [diff] [blame] | 229 | if (pm) |
| 230 | return pm_generic_thaw(dev); |
| 231 | else |
| 232 | return i2c_legacy_resume(dev); |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 233 | } |
| 234 | |
| 235 | static int i2c_device_pm_poweroff(struct device *dev) |
| 236 | { |
| 237 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 238 | |
Mark Brown | d529de2 | 2011-01-14 22:03:49 +0100 | [diff] [blame] | 239 | if (pm) |
| 240 | return pm_generic_poweroff(dev); |
| 241 | else |
| 242 | return i2c_legacy_suspend(dev, PMSG_HIBERNATE); |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 243 | } |
| 244 | |
| 245 | static int i2c_device_pm_restore(struct device *dev) |
| 246 | { |
| 247 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 248 | |
| 249 | if (pm) |
Mark Brown | d529de2 | 2011-01-14 22:03:49 +0100 | [diff] [blame] | 250 | return pm_generic_restore(dev); |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 251 | else |
Mark Brown | d529de2 | 2011-01-14 22:03:49 +0100 | [diff] [blame] | 252 | return i2c_legacy_resume(dev); |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 253 | } |
| 254 | #else /* !CONFIG_PM_SLEEP */ |
| 255 | #define i2c_device_pm_suspend NULL |
| 256 | #define i2c_device_pm_resume NULL |
| 257 | #define i2c_device_pm_freeze NULL |
| 258 | #define i2c_device_pm_thaw NULL |
| 259 | #define i2c_device_pm_poweroff NULL |
| 260 | #define i2c_device_pm_restore NULL |
| 261 | #endif /* !CONFIG_PM_SLEEP */ |
| 262 | |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 263 | static void i2c_client_dev_release(struct device *dev) |
| 264 | { |
| 265 | kfree(to_i2c_client(dev)); |
| 266 | } |
| 267 | |
Zhenwen Xu | 09b8ce0 | 2009-03-28 21:34:46 +0100 | [diff] [blame] | 268 | static ssize_t |
Jean Delvare | 4f8cf82 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 269 | show_name(struct device *dev, struct device_attribute *attr, char *buf) |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 270 | { |
Jean Delvare | 4f8cf82 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 271 | return sprintf(buf, "%s\n", dev->type == &i2c_client_type ? |
| 272 | to_i2c_client(dev)->name : to_i2c_adapter(dev)->name); |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 273 | } |
| 274 | |
Zhenwen Xu | 09b8ce0 | 2009-03-28 21:34:46 +0100 | [diff] [blame] | 275 | static ssize_t |
| 276 | show_modalias(struct device *dev, struct device_attribute *attr, char *buf) |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 277 | { |
| 278 | struct i2c_client *client = to_i2c_client(dev); |
Jean Delvare | eb8a790 | 2008-05-18 20:49:41 +0200 | [diff] [blame] | 279 | return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 280 | } |
| 281 | |
Jean Delvare | 4f8cf82 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 282 | static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 283 | static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL); |
| 284 | |
| 285 | static struct attribute *i2c_dev_attrs[] = { |
| 286 | &dev_attr_name.attr, |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 287 | /* modalias helps coldplug: modprobe $(cat .../modalias) */ |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 288 | &dev_attr_modalias.attr, |
| 289 | NULL |
| 290 | }; |
| 291 | |
| 292 | static struct attribute_group i2c_dev_attr_group = { |
| 293 | .attrs = i2c_dev_attrs, |
| 294 | }; |
| 295 | |
| 296 | static const struct attribute_group *i2c_dev_attr_groups[] = { |
| 297 | &i2c_dev_attr_group, |
| 298 | NULL |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 299 | }; |
| 300 | |
Tobias Klauser | 0b2c368 | 2010-01-16 20:43:12 +0100 | [diff] [blame] | 301 | static const struct dev_pm_ops i2c_device_pm_ops = { |
sonic zhang | 54067ee | 2009-12-14 21:17:30 +0100 | [diff] [blame] | 302 | .suspend = i2c_device_pm_suspend, |
| 303 | .resume = i2c_device_pm_resume, |
Rafael J. Wysocki | 2f60ba7 | 2010-05-10 23:09:30 +0200 | [diff] [blame] | 304 | .freeze = i2c_device_pm_freeze, |
| 305 | .thaw = i2c_device_pm_thaw, |
| 306 | .poweroff = i2c_device_pm_poweroff, |
| 307 | .restore = i2c_device_pm_restore, |
| 308 | SET_RUNTIME_PM_OPS( |
| 309 | pm_generic_runtime_suspend, |
| 310 | pm_generic_runtime_resume, |
| 311 | pm_generic_runtime_idle |
| 312 | ) |
sonic zhang | 54067ee | 2009-12-14 21:17:30 +0100 | [diff] [blame] | 313 | }; |
| 314 | |
Jon Smirl | e9ca9eb | 2008-07-14 22:38:35 +0200 | [diff] [blame] | 315 | struct bus_type i2c_bus_type = { |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 316 | .name = "i2c", |
| 317 | .match = i2c_device_match, |
| 318 | .probe = i2c_device_probe, |
| 319 | .remove = i2c_device_remove, |
| 320 | .shutdown = i2c_device_shutdown, |
sonic zhang | 54067ee | 2009-12-14 21:17:30 +0100 | [diff] [blame] | 321 | .pm = &i2c_device_pm_ops, |
Russell King | b864c7d | 2006-01-05 14:37:50 +0000 | [diff] [blame] | 322 | }; |
Jon Smirl | e9ca9eb | 2008-07-14 22:38:35 +0200 | [diff] [blame] | 323 | EXPORT_SYMBOL_GPL(i2c_bus_type); |
Russell King | b864c7d | 2006-01-05 14:37:50 +0000 | [diff] [blame] | 324 | |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 325 | static struct device_type i2c_client_type = { |
| 326 | .groups = i2c_dev_attr_groups, |
| 327 | .uevent = i2c_device_uevent, |
| 328 | .release = i2c_client_dev_release, |
| 329 | }; |
| 330 | |
David Brownell | 9b766b8 | 2008-01-27 18:14:51 +0100 | [diff] [blame] | 331 | |
| 332 | /** |
| 333 | * i2c_verify_client - return parameter as i2c_client, or NULL |
| 334 | * @dev: device, probably from some driver model iterator |
| 335 | * |
| 336 | * When traversing the driver model tree, perhaps using driver model |
| 337 | * iterators like @device_for_each_child(), you can't assume very much |
| 338 | * about the nodes you find. Use this function to avoid oopses caused |
| 339 | * by wrongly treating some non-I2C device as an i2c_client. |
| 340 | */ |
| 341 | struct i2c_client *i2c_verify_client(struct device *dev) |
| 342 | { |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 343 | return (dev->type == &i2c_client_type) |
David Brownell | 9b766b8 | 2008-01-27 18:14:51 +0100 | [diff] [blame] | 344 | ? to_i2c_client(dev) |
| 345 | : NULL; |
| 346 | } |
| 347 | EXPORT_SYMBOL(i2c_verify_client); |
| 348 | |
| 349 | |
Jean Delvare | 3a89db5 | 2010-06-03 11:33:52 +0200 | [diff] [blame] | 350 | /* This is a permissive address validity check, I2C address map constraints |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 351 | * are purposely not enforced, except for the general call address. */ |
Jean Delvare | 3a89db5 | 2010-06-03 11:33:52 +0200 | [diff] [blame] | 352 | static int i2c_check_client_addr_validity(const struct i2c_client *client) |
| 353 | { |
| 354 | if (client->flags & I2C_CLIENT_TEN) { |
| 355 | /* 10-bit address, all values are valid */ |
| 356 | if (client->addr > 0x3ff) |
| 357 | return -EINVAL; |
| 358 | } else { |
| 359 | /* 7-bit address, reject the general call address */ |
| 360 | if (client->addr == 0x00 || client->addr > 0x7f) |
| 361 | return -EINVAL; |
| 362 | } |
| 363 | return 0; |
| 364 | } |
| 365 | |
Jean Delvare | 656b876 | 2010-06-03 11:33:53 +0200 | [diff] [blame] | 366 | /* And this is a strict address validity check, used when probing. If a |
| 367 | * device uses a reserved address, then it shouldn't be probed. 7-bit |
| 368 | * addressing is assumed, 10-bit address devices are rare and should be |
| 369 | * explicitly enumerated. */ |
| 370 | static int i2c_check_addr_validity(unsigned short addr) |
| 371 | { |
| 372 | /* |
| 373 | * Reserved addresses per I2C specification: |
| 374 | * 0x00 General call address / START byte |
| 375 | * 0x01 CBUS address |
| 376 | * 0x02 Reserved for different bus format |
| 377 | * 0x03 Reserved for future purposes |
| 378 | * 0x04-0x07 Hs-mode master code |
| 379 | * 0x78-0x7b 10-bit slave addressing |
| 380 | * 0x7c-0x7f Reserved for future purposes |
| 381 | */ |
| 382 | if (addr < 0x08 || addr > 0x77) |
| 383 | return -EINVAL; |
| 384 | return 0; |
| 385 | } |
| 386 | |
Jean Delvare | 3b5f794 | 2010-06-03 11:33:55 +0200 | [diff] [blame] | 387 | static int __i2c_check_addr_busy(struct device *dev, void *addrp) |
| 388 | { |
| 389 | struct i2c_client *client = i2c_verify_client(dev); |
| 390 | int addr = *(int *)addrp; |
| 391 | |
| 392 | if (client && client->addr == addr) |
| 393 | return -EBUSY; |
| 394 | return 0; |
| 395 | } |
| 396 | |
Michael Lawnick | 0826374 | 2010-08-11 18:21:02 +0200 | [diff] [blame] | 397 | /* walk up mux tree */ |
| 398 | static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr) |
| 399 | { |
Jean Delvare | 97cc4d4 | 2010-10-24 18:16:57 +0200 | [diff] [blame] | 400 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
Michael Lawnick | 0826374 | 2010-08-11 18:21:02 +0200 | [diff] [blame] | 401 | int result; |
| 402 | |
| 403 | result = device_for_each_child(&adapter->dev, &addr, |
| 404 | __i2c_check_addr_busy); |
| 405 | |
Jean Delvare | 97cc4d4 | 2010-10-24 18:16:57 +0200 | [diff] [blame] | 406 | if (!result && parent) |
| 407 | result = i2c_check_mux_parents(parent, addr); |
Michael Lawnick | 0826374 | 2010-08-11 18:21:02 +0200 | [diff] [blame] | 408 | |
| 409 | return result; |
| 410 | } |
| 411 | |
| 412 | /* recurse down mux tree */ |
| 413 | static int i2c_check_mux_children(struct device *dev, void *addrp) |
| 414 | { |
| 415 | int result; |
| 416 | |
| 417 | if (dev->type == &i2c_adapter_type) |
| 418 | result = device_for_each_child(dev, addrp, |
| 419 | i2c_check_mux_children); |
| 420 | else |
| 421 | result = __i2c_check_addr_busy(dev, addrp); |
| 422 | |
| 423 | return result; |
| 424 | } |
| 425 | |
Jean Delvare | 3b5f794 | 2010-06-03 11:33:55 +0200 | [diff] [blame] | 426 | static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) |
| 427 | { |
Jean Delvare | 97cc4d4 | 2010-10-24 18:16:57 +0200 | [diff] [blame] | 428 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
Michael Lawnick | 0826374 | 2010-08-11 18:21:02 +0200 | [diff] [blame] | 429 | int result = 0; |
| 430 | |
Jean Delvare | 97cc4d4 | 2010-10-24 18:16:57 +0200 | [diff] [blame] | 431 | if (parent) |
| 432 | result = i2c_check_mux_parents(parent, addr); |
Michael Lawnick | 0826374 | 2010-08-11 18:21:02 +0200 | [diff] [blame] | 433 | |
| 434 | if (!result) |
| 435 | result = device_for_each_child(&adapter->dev, &addr, |
| 436 | i2c_check_mux_children); |
| 437 | |
| 438 | return result; |
Jean Delvare | 3b5f794 | 2010-06-03 11:33:55 +0200 | [diff] [blame] | 439 | } |
| 440 | |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 441 | /** |
Jean Delvare | fe61e07 | 2010-08-11 18:20:58 +0200 | [diff] [blame] | 442 | * i2c_lock_adapter - Get exclusive access to an I2C bus segment |
| 443 | * @adapter: Target I2C bus segment |
| 444 | */ |
| 445 | void i2c_lock_adapter(struct i2c_adapter *adapter) |
| 446 | { |
Jean Delvare | 97cc4d4 | 2010-10-24 18:16:57 +0200 | [diff] [blame] | 447 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
| 448 | |
| 449 | if (parent) |
| 450 | i2c_lock_adapter(parent); |
Michael Lawnick | 0826374 | 2010-08-11 18:21:02 +0200 | [diff] [blame] | 451 | else |
| 452 | rt_mutex_lock(&adapter->bus_lock); |
Jean Delvare | fe61e07 | 2010-08-11 18:20:58 +0200 | [diff] [blame] | 453 | } |
| 454 | EXPORT_SYMBOL_GPL(i2c_lock_adapter); |
| 455 | |
| 456 | /** |
| 457 | * i2c_trylock_adapter - Try to get exclusive access to an I2C bus segment |
| 458 | * @adapter: Target I2C bus segment |
| 459 | */ |
| 460 | static int i2c_trylock_adapter(struct i2c_adapter *adapter) |
| 461 | { |
Jean Delvare | 97cc4d4 | 2010-10-24 18:16:57 +0200 | [diff] [blame] | 462 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
| 463 | |
| 464 | if (parent) |
| 465 | return i2c_trylock_adapter(parent); |
Michael Lawnick | 0826374 | 2010-08-11 18:21:02 +0200 | [diff] [blame] | 466 | else |
| 467 | return rt_mutex_trylock(&adapter->bus_lock); |
Jean Delvare | fe61e07 | 2010-08-11 18:20:58 +0200 | [diff] [blame] | 468 | } |
| 469 | |
| 470 | /** |
| 471 | * i2c_unlock_adapter - Release exclusive access to an I2C bus segment |
| 472 | * @adapter: Target I2C bus segment |
| 473 | */ |
| 474 | void i2c_unlock_adapter(struct i2c_adapter *adapter) |
| 475 | { |
Jean Delvare | 97cc4d4 | 2010-10-24 18:16:57 +0200 | [diff] [blame] | 476 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
| 477 | |
| 478 | if (parent) |
| 479 | i2c_unlock_adapter(parent); |
Michael Lawnick | 0826374 | 2010-08-11 18:21:02 +0200 | [diff] [blame] | 480 | else |
| 481 | rt_mutex_unlock(&adapter->bus_lock); |
Jean Delvare | fe61e07 | 2010-08-11 18:20:58 +0200 | [diff] [blame] | 482 | } |
| 483 | EXPORT_SYMBOL_GPL(i2c_unlock_adapter); |
| 484 | |
| 485 | /** |
Jean Delvare | f8a227e | 2009-06-19 16:58:18 +0200 | [diff] [blame] | 486 | * i2c_new_device - instantiate an i2c device |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 487 | * @adap: the adapter managing the device |
| 488 | * @info: describes one I2C device; bus_num is ignored |
David Brownell | d64f73b | 2007-07-12 14:12:28 +0200 | [diff] [blame] | 489 | * Context: can sleep |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 490 | * |
Jean Delvare | f8a227e | 2009-06-19 16:58:18 +0200 | [diff] [blame] | 491 | * Create an i2c device. Binding is handled through driver model |
| 492 | * probe()/remove() methods. A driver may be bound to this device when we |
| 493 | * return from this function, or any later moment (e.g. maybe hotplugging will |
| 494 | * load the driver module). This call is not appropriate for use by mainboard |
| 495 | * initialization logic, which usually runs during an arch_initcall() long |
| 496 | * before any i2c_adapter could exist. |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 497 | * |
| 498 | * This returns the new i2c client, which may be saved for later use with |
| 499 | * i2c_unregister_device(); or NULL to indicate an error. |
| 500 | */ |
| 501 | struct i2c_client * |
| 502 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) |
| 503 | { |
| 504 | struct i2c_client *client; |
| 505 | int status; |
| 506 | |
| 507 | client = kzalloc(sizeof *client, GFP_KERNEL); |
| 508 | if (!client) |
| 509 | return NULL; |
| 510 | |
| 511 | client->adapter = adap; |
| 512 | |
| 513 | client->dev.platform_data = info->platform_data; |
David Brownell | 3bbb835 | 2007-10-13 23:56:29 +0200 | [diff] [blame] | 514 | |
Anton Vorontsov | 11f1f2a | 2008-10-22 20:21:33 +0200 | [diff] [blame] | 515 | if (info->archdata) |
| 516 | client->dev.archdata = *info->archdata; |
| 517 | |
Marc Pignat | ee35425 | 2008-08-28 08:33:22 +0200 | [diff] [blame] | 518 | client->flags = info->flags; |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 519 | client->addr = info->addr; |
| 520 | client->irq = info->irq; |
| 521 | |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 522 | strlcpy(client->name, info->type, sizeof(client->name)); |
| 523 | |
Jean Delvare | 3a89db5 | 2010-06-03 11:33:52 +0200 | [diff] [blame] | 524 | /* Check for address validity */ |
| 525 | status = i2c_check_client_addr_validity(client); |
| 526 | if (status) { |
| 527 | dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n", |
| 528 | client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr); |
| 529 | goto out_err_silent; |
| 530 | } |
| 531 | |
Jean Delvare | f8a227e | 2009-06-19 16:58:18 +0200 | [diff] [blame] | 532 | /* Check for address business */ |
Jean Delvare | 3b5f794 | 2010-06-03 11:33:55 +0200 | [diff] [blame] | 533 | status = i2c_check_addr_busy(adap, client->addr); |
Jean Delvare | f8a227e | 2009-06-19 16:58:18 +0200 | [diff] [blame] | 534 | if (status) |
| 535 | goto out_err; |
| 536 | |
| 537 | client->dev.parent = &client->adapter->dev; |
| 538 | client->dev.bus = &i2c_bus_type; |
Jean Delvare | 51298d1 | 2009-09-18 22:45:45 +0200 | [diff] [blame] | 539 | client->dev.type = &i2c_client_type; |
Grant Likely | d12d42f | 2010-04-13 16:12:28 -0700 | [diff] [blame] | 540 | client->dev.of_node = info->of_node; |
Jean Delvare | f8a227e | 2009-06-19 16:58:18 +0200 | [diff] [blame] | 541 | |
| 542 | dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), |
| 543 | client->addr); |
| 544 | status = device_register(&client->dev); |
| 545 | if (status) |
| 546 | goto out_err; |
| 547 | |
Jean Delvare | f8a227e | 2009-06-19 16:58:18 +0200 | [diff] [blame] | 548 | dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", |
| 549 | client->name, dev_name(&client->dev)); |
| 550 | |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 551 | return client; |
Jean Delvare | f8a227e | 2009-06-19 16:58:18 +0200 | [diff] [blame] | 552 | |
| 553 | out_err: |
| 554 | dev_err(&adap->dev, "Failed to register i2c client %s at 0x%02x " |
| 555 | "(%d)\n", client->name, client->addr, status); |
Jean Delvare | 3a89db5 | 2010-06-03 11:33:52 +0200 | [diff] [blame] | 556 | out_err_silent: |
Jean Delvare | f8a227e | 2009-06-19 16:58:18 +0200 | [diff] [blame] | 557 | kfree(client); |
| 558 | return NULL; |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 559 | } |
| 560 | EXPORT_SYMBOL_GPL(i2c_new_device); |
| 561 | |
| 562 | |
| 563 | /** |
| 564 | * i2c_unregister_device - reverse effect of i2c_new_device() |
| 565 | * @client: value returned from i2c_new_device() |
David Brownell | d64f73b | 2007-07-12 14:12:28 +0200 | [diff] [blame] | 566 | * Context: can sleep |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 567 | */ |
| 568 | void i2c_unregister_device(struct i2c_client *client) |
David Brownell | a1d9e6e | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 569 | { |
David Brownell | a1d9e6e | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 570 | device_unregister(&client->dev); |
| 571 | } |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 572 | EXPORT_SYMBOL_GPL(i2c_unregister_device); |
David Brownell | a1d9e6e | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 573 | |
| 574 | |
Jean Delvare | 60b129d | 2008-05-11 20:37:06 +0200 | [diff] [blame] | 575 | static const struct i2c_device_id dummy_id[] = { |
| 576 | { "dummy", 0 }, |
| 577 | { }, |
| 578 | }; |
| 579 | |
Jean Delvare | d2653e9 | 2008-04-29 23:11:39 +0200 | [diff] [blame] | 580 | static int dummy_probe(struct i2c_client *client, |
| 581 | const struct i2c_device_id *id) |
| 582 | { |
| 583 | return 0; |
| 584 | } |
| 585 | |
| 586 | static int dummy_remove(struct i2c_client *client) |
David Brownell | e9f1373 | 2008-01-27 18:14:52 +0100 | [diff] [blame] | 587 | { |
| 588 | return 0; |
| 589 | } |
| 590 | |
| 591 | static struct i2c_driver dummy_driver = { |
| 592 | .driver.name = "dummy", |
Jean Delvare | d2653e9 | 2008-04-29 23:11:39 +0200 | [diff] [blame] | 593 | .probe = dummy_probe, |
| 594 | .remove = dummy_remove, |
Jean Delvare | 60b129d | 2008-05-11 20:37:06 +0200 | [diff] [blame] | 595 | .id_table = dummy_id, |
David Brownell | e9f1373 | 2008-01-27 18:14:52 +0100 | [diff] [blame] | 596 | }; |
| 597 | |
| 598 | /** |
| 599 | * i2c_new_dummy - return a new i2c device bound to a dummy driver |
| 600 | * @adapter: the adapter managing the device |
| 601 | * @address: seven bit address to be used |
David Brownell | e9f1373 | 2008-01-27 18:14:52 +0100 | [diff] [blame] | 602 | * Context: can sleep |
| 603 | * |
| 604 | * This returns an I2C client bound to the "dummy" driver, intended for use |
| 605 | * with devices that consume multiple addresses. Examples of such chips |
| 606 | * include various EEPROMS (like 24c04 and 24c08 models). |
| 607 | * |
| 608 | * These dummy devices have two main uses. First, most I2C and SMBus calls |
| 609 | * except i2c_transfer() need a client handle; the dummy will be that handle. |
| 610 | * And second, this prevents the specified address from being bound to a |
| 611 | * different driver. |
| 612 | * |
| 613 | * This returns the new i2c client, which should be saved for later use with |
| 614 | * i2c_unregister_device(); or NULL to indicate an error. |
| 615 | */ |
Zhenwen Xu | 09b8ce0 | 2009-03-28 21:34:46 +0100 | [diff] [blame] | 616 | struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) |
David Brownell | e9f1373 | 2008-01-27 18:14:52 +0100 | [diff] [blame] | 617 | { |
| 618 | struct i2c_board_info info = { |
Jean Delvare | 60b129d | 2008-05-11 20:37:06 +0200 | [diff] [blame] | 619 | I2C_BOARD_INFO("dummy", address), |
David Brownell | e9f1373 | 2008-01-27 18:14:52 +0100 | [diff] [blame] | 620 | }; |
| 621 | |
David Brownell | e9f1373 | 2008-01-27 18:14:52 +0100 | [diff] [blame] | 622 | return i2c_new_device(adapter, &info); |
| 623 | } |
| 624 | EXPORT_SYMBOL_GPL(i2c_new_dummy); |
| 625 | |
David Brownell | f37dd80 | 2007-02-13 22:09:00 +0100 | [diff] [blame] | 626 | /* ------------------------------------------------------------------------- */ |
| 627 | |
David Brownell | 16ffadf | 2007-05-01 23:26:28 +0200 | [diff] [blame] | 628 | /* I2C bus adapters -- one roots each I2C or SMBUS segment */ |
| 629 | |
Adrian Bunk | 83eaaed | 2007-10-13 23:56:30 +0200 | [diff] [blame] | 630 | static void i2c_adapter_dev_release(struct device *dev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 631 | { |
David Brownell | ef2c8321 | 2007-05-01 23:26:28 +0200 | [diff] [blame] | 632 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 633 | complete(&adap->dev_released); |
| 634 | } |
| 635 | |
Jean Delvare | 99cd8e2 | 2009-06-19 16:58:20 +0200 | [diff] [blame] | 636 | /* |
| 637 | * Let users instantiate I2C devices through sysfs. This can be used when |
| 638 | * platform initialization code doesn't contain the proper data for |
| 639 | * whatever reason. Also useful for drivers that do device detection and |
| 640 | * detection fails, either because the device uses an unexpected address, |
| 641 | * or this is a compatible device with different ID register values. |
| 642 | * |
| 643 | * Parameter checking may look overzealous, but we really don't want |
| 644 | * the user to provide incorrect parameters. |
| 645 | */ |
| 646 | static ssize_t |
| 647 | i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, |
| 648 | const char *buf, size_t count) |
| 649 | { |
| 650 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
| 651 | struct i2c_board_info info; |
| 652 | struct i2c_client *client; |
| 653 | char *blank, end; |
| 654 | int res; |
| 655 | |
Jean Delvare | 99cd8e2 | 2009-06-19 16:58:20 +0200 | [diff] [blame] | 656 | memset(&info, 0, sizeof(struct i2c_board_info)); |
| 657 | |
| 658 | blank = strchr(buf, ' '); |
| 659 | if (!blank) { |
| 660 | dev_err(dev, "%s: Missing parameters\n", "new_device"); |
| 661 | return -EINVAL; |
| 662 | } |
| 663 | if (blank - buf > I2C_NAME_SIZE - 1) { |
| 664 | dev_err(dev, "%s: Invalid device name\n", "new_device"); |
| 665 | return -EINVAL; |
| 666 | } |
| 667 | memcpy(info.type, buf, blank - buf); |
| 668 | |
| 669 | /* Parse remaining parameters, reject extra parameters */ |
| 670 | res = sscanf(++blank, "%hi%c", &info.addr, &end); |
| 671 | if (res < 1) { |
| 672 | dev_err(dev, "%s: Can't parse I2C address\n", "new_device"); |
| 673 | return -EINVAL; |
| 674 | } |
| 675 | if (res > 1 && end != '\n') { |
| 676 | dev_err(dev, "%s: Extra parameters\n", "new_device"); |
| 677 | return -EINVAL; |
| 678 | } |
| 679 | |
Jean Delvare | 99cd8e2 | 2009-06-19 16:58:20 +0200 | [diff] [blame] | 680 | client = i2c_new_device(adap, &info); |
| 681 | if (!client) |
Jean Delvare | 3a89db5 | 2010-06-03 11:33:52 +0200 | [diff] [blame] | 682 | return -EINVAL; |
Jean Delvare | 99cd8e2 | 2009-06-19 16:58:20 +0200 | [diff] [blame] | 683 | |
| 684 | /* Keep track of the added device */ |
Jean Delvare | dafc50d | 2010-08-11 18:21:01 +0200 | [diff] [blame] | 685 | mutex_lock(&adap->userspace_clients_lock); |
Jean Delvare | 6629dcf | 2010-05-04 11:09:28 +0200 | [diff] [blame] | 686 | list_add_tail(&client->detected, &adap->userspace_clients); |
Jean Delvare | dafc50d | 2010-08-11 18:21:01 +0200 | [diff] [blame] | 687 | mutex_unlock(&adap->userspace_clients_lock); |
Jean Delvare | 99cd8e2 | 2009-06-19 16:58:20 +0200 | [diff] [blame] | 688 | dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", |
| 689 | info.type, info.addr); |
| 690 | |
| 691 | return count; |
| 692 | } |
| 693 | |
| 694 | /* |
| 695 | * And of course let the users delete the devices they instantiated, if |
| 696 | * they got it wrong. This interface can only be used to delete devices |
| 697 | * instantiated by i2c_sysfs_new_device above. This guarantees that we |
| 698 | * don't delete devices to which some kernel code still has references. |
| 699 | * |
| 700 | * Parameter checking may look overzealous, but we really don't want |
| 701 | * the user to delete the wrong device. |
| 702 | */ |
| 703 | static ssize_t |
| 704 | i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr, |
| 705 | const char *buf, size_t count) |
| 706 | { |
| 707 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
| 708 | struct i2c_client *client, *next; |
| 709 | unsigned short addr; |
| 710 | char end; |
| 711 | int res; |
| 712 | |
| 713 | /* Parse parameters, reject extra parameters */ |
| 714 | res = sscanf(buf, "%hi%c", &addr, &end); |
| 715 | if (res < 1) { |
| 716 | dev_err(dev, "%s: Can't parse I2C address\n", "delete_device"); |
| 717 | return -EINVAL; |
| 718 | } |
| 719 | if (res > 1 && end != '\n') { |
| 720 | dev_err(dev, "%s: Extra parameters\n", "delete_device"); |
| 721 | return -EINVAL; |
| 722 | } |
| 723 | |
| 724 | /* Make sure the device was added through sysfs */ |
| 725 | res = -ENOENT; |
Jean Delvare | dafc50d | 2010-08-11 18:21:01 +0200 | [diff] [blame] | 726 | mutex_lock(&adap->userspace_clients_lock); |
Jean Delvare | 6629dcf | 2010-05-04 11:09:28 +0200 | [diff] [blame] | 727 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
| 728 | detected) { |
| 729 | if (client->addr == addr) { |
Jean Delvare | 99cd8e2 | 2009-06-19 16:58:20 +0200 | [diff] [blame] | 730 | dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", |
| 731 | "delete_device", client->name, client->addr); |
| 732 | |
| 733 | list_del(&client->detected); |
| 734 | i2c_unregister_device(client); |
| 735 | res = count; |
| 736 | break; |
| 737 | } |
| 738 | } |
Jean Delvare | dafc50d | 2010-08-11 18:21:01 +0200 | [diff] [blame] | 739 | mutex_unlock(&adap->userspace_clients_lock); |
Jean Delvare | 99cd8e2 | 2009-06-19 16:58:20 +0200 | [diff] [blame] | 740 | |
| 741 | if (res < 0) |
| 742 | dev_err(dev, "%s: Can't find device in list\n", |
| 743 | "delete_device"); |
| 744 | return res; |
| 745 | } |
| 746 | |
Jean Delvare | 4f8cf82 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 747 | static DEVICE_ATTR(new_device, S_IWUSR, NULL, i2c_sysfs_new_device); |
| 748 | static DEVICE_ATTR(delete_device, S_IWUSR, NULL, i2c_sysfs_delete_device); |
| 749 | |
| 750 | static struct attribute *i2c_adapter_attrs[] = { |
| 751 | &dev_attr_name.attr, |
| 752 | &dev_attr_new_device.attr, |
| 753 | &dev_attr_delete_device.attr, |
| 754 | NULL |
David Brownell | 16ffadf | 2007-05-01 23:26:28 +0200 | [diff] [blame] | 755 | }; |
| 756 | |
Jean Delvare | 4f8cf82 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 757 | static struct attribute_group i2c_adapter_attr_group = { |
| 758 | .attrs = i2c_adapter_attrs, |
| 759 | }; |
| 760 | |
| 761 | static const struct attribute_group *i2c_adapter_attr_groups[] = { |
| 762 | &i2c_adapter_attr_group, |
| 763 | NULL |
| 764 | }; |
| 765 | |
Michael Lawnick | 0826374 | 2010-08-11 18:21:02 +0200 | [diff] [blame] | 766 | struct device_type i2c_adapter_type = { |
Jean Delvare | 4f8cf82 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 767 | .groups = i2c_adapter_attr_groups, |
| 768 | .release = i2c_adapter_dev_release, |
David Brownell | 16ffadf | 2007-05-01 23:26:28 +0200 | [diff] [blame] | 769 | }; |
Michael Lawnick | 0826374 | 2010-08-11 18:21:02 +0200 | [diff] [blame] | 770 | EXPORT_SYMBOL_GPL(i2c_adapter_type); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 771 | |
Jean Delvare | 2bb5095 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 772 | #ifdef CONFIG_I2C_COMPAT |
| 773 | static struct class_compat *i2c_adapter_compat_class; |
| 774 | #endif |
| 775 | |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 776 | static void i2c_scan_static_board_info(struct i2c_adapter *adapter) |
| 777 | { |
| 778 | struct i2c_devinfo *devinfo; |
| 779 | |
Rodolfo Giometti | f18c41d | 2009-06-19 16:58:20 +0200 | [diff] [blame] | 780 | down_read(&__i2c_board_lock); |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 781 | list_for_each_entry(devinfo, &__i2c_board_list, list) { |
| 782 | if (devinfo->busnum == adapter->nr |
| 783 | && !i2c_new_device(adapter, |
| 784 | &devinfo->board_info)) |
Zhenwen Xu | 09b8ce0 | 2009-03-28 21:34:46 +0100 | [diff] [blame] | 785 | dev_err(&adapter->dev, |
| 786 | "Can't create device at 0x%02x\n", |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 787 | devinfo->board_info.addr); |
| 788 | } |
Rodolfo Giometti | f18c41d | 2009-06-19 16:58:20 +0200 | [diff] [blame] | 789 | up_read(&__i2c_board_lock); |
David Brownell | 9c1600e | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 790 | } |
| 791 | |
Jean Delvare | 69b0089 | 2009-12-06 17:06:27 +0100 | [diff] [blame] | 792 | static int i2c_do_add_adapter(struct i2c_driver *driver, |
| 793 | struct i2c_adapter *adap) |
Jean Delvare | 026526f | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 794 | { |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 795 | /* Detect supported devices on that bus, and instantiate them */ |
| 796 | i2c_detect(adap, driver); |
| 797 | |
| 798 | /* Let legacy drivers scan this bus for matching devices */ |
Jean Delvare | 026526f | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 799 | if (driver->attach_adapter) { |
Jean Delvare | a920ff4 | 2011-04-17 10:20:19 +0200 | [diff] [blame] | 800 | dev_warn(&adap->dev, "%s: attach_adapter method is deprecated\n", |
| 801 | driver->driver.name); |
Jean Delvare | fe6fc25 | 2011-03-20 14:50:53 +0100 | [diff] [blame] | 802 | dev_warn(&adap->dev, "Please use another way to instantiate " |
| 803 | "your i2c_client\n"); |
Jean Delvare | 026526f | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 804 | /* We ignore the return code; if it fails, too bad */ |
| 805 | driver->attach_adapter(adap); |
| 806 | } |
| 807 | return 0; |
| 808 | } |
| 809 | |
Jean Delvare | 69b0089 | 2009-12-06 17:06:27 +0100 | [diff] [blame] | 810 | static int __process_new_adapter(struct device_driver *d, void *data) |
| 811 | { |
| 812 | return i2c_do_add_adapter(to_i2c_driver(d), data); |
| 813 | } |
| 814 | |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 815 | static int i2c_register_adapter(struct i2c_adapter *adap) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 816 | { |
Jean Delvare | d670328 | 2010-08-11 18:20:59 +0200 | [diff] [blame] | 817 | int res = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 818 | |
David Brownell | 1d0b19c | 2008-10-14 17:30:05 +0200 | [diff] [blame] | 819 | /* Can't register until after driver model init */ |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 820 | if (unlikely(WARN_ON(!i2c_bus_type.p))) { |
| 821 | res = -EAGAIN; |
| 822 | goto out_list; |
| 823 | } |
David Brownell | 1d0b19c | 2008-10-14 17:30:05 +0200 | [diff] [blame] | 824 | |
Jean Delvare | 2236baa | 2010-11-15 22:40:38 +0100 | [diff] [blame] | 825 | /* Sanity checks */ |
| 826 | if (unlikely(adap->name[0] == '\0')) { |
| 827 | pr_err("i2c-core: Attempt to register an adapter with " |
| 828 | "no name!\n"); |
| 829 | return -EINVAL; |
| 830 | } |
| 831 | if (unlikely(!adap->algo)) { |
| 832 | pr_err("i2c-core: Attempt to register adapter '%s' with " |
| 833 | "no algo!\n", adap->name); |
| 834 | return -EINVAL; |
| 835 | } |
| 836 | |
Mika Kuoppala | 194684e | 2009-12-06 17:06:22 +0100 | [diff] [blame] | 837 | rt_mutex_init(&adap->bus_lock); |
Jean Delvare | dafc50d | 2010-08-11 18:21:01 +0200 | [diff] [blame] | 838 | mutex_init(&adap->userspace_clients_lock); |
Jean Delvare | 6629dcf | 2010-05-04 11:09:28 +0200 | [diff] [blame] | 839 | INIT_LIST_HEAD(&adap->userspace_clients); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 840 | |
Jean Delvare | 8fcfef6 | 2009-03-28 21:34:43 +0100 | [diff] [blame] | 841 | /* Set default timeout to 1 second if not already set */ |
| 842 | if (adap->timeout == 0) |
| 843 | adap->timeout = HZ; |
| 844 | |
Kay Sievers | 27d9c18 | 2009-01-07 14:29:16 +0100 | [diff] [blame] | 845 | dev_set_name(&adap->dev, "i2c-%d", adap->nr); |
Jean Delvare | 4f8cf82 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 846 | adap->dev.bus = &i2c_bus_type; |
| 847 | adap->dev.type = &i2c_adapter_type; |
Jean Delvare | b119c6c | 2006-08-15 18:26:30 +0200 | [diff] [blame] | 848 | res = device_register(&adap->dev); |
| 849 | if (res) |
| 850 | goto out_list; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 851 | |
Jean Delvare | b6d7b3d | 2005-07-31 19:02:53 +0200 | [diff] [blame] | 852 | dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); |
| 853 | |
Jean Delvare | 2bb5095 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 854 | #ifdef CONFIG_I2C_COMPAT |
| 855 | res = class_compat_create_link(i2c_adapter_compat_class, &adap->dev, |
| 856 | adap->dev.parent); |
| 857 | if (res) |
| 858 | dev_warn(&adap->dev, |
| 859 | "Failed to create compatibility class link\n"); |
| 860 | #endif |
| 861 | |
Jean Delvare | 729d6dd | 2009-06-19 16:58:18 +0200 | [diff] [blame] | 862 | /* create pre-declared device nodes */ |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 863 | if (adap->nr < __i2c_first_dynamic_bus_num) |
| 864 | i2c_scan_static_board_info(adap); |
| 865 | |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 866 | /* Notify drivers */ |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 867 | mutex_lock(&core_lock); |
Jean Delvare | d670328 | 2010-08-11 18:20:59 +0200 | [diff] [blame] | 868 | bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); |
Jean Delvare | caada32 | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 869 | mutex_unlock(&core_lock); |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 870 | |
| 871 | return 0; |
Jean Delvare | b119c6c | 2006-08-15 18:26:30 +0200 | [diff] [blame] | 872 | |
Jean Delvare | b119c6c | 2006-08-15 18:26:30 +0200 | [diff] [blame] | 873 | out_list: |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 874 | mutex_lock(&core_lock); |
Jean Delvare | b119c6c | 2006-08-15 18:26:30 +0200 | [diff] [blame] | 875 | idr_remove(&i2c_adapter_idr, adap->nr); |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 876 | mutex_unlock(&core_lock); |
| 877 | return res; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 878 | } |
| 879 | |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 880 | /** |
| 881 | * i2c_add_adapter - declare i2c adapter, use dynamic bus number |
| 882 | * @adapter: the adapter to add |
David Brownell | d64f73b | 2007-07-12 14:12:28 +0200 | [diff] [blame] | 883 | * Context: can sleep |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 884 | * |
| 885 | * This routine is used to declare an I2C adapter when its bus number |
| 886 | * doesn't matter. Examples: for I2C adapters dynamically added by |
| 887 | * USB links or PCI plugin cards. |
| 888 | * |
| 889 | * When this returns zero, a new bus number was allocated and stored |
| 890 | * in adap->nr, and the specified adapter became available for clients. |
| 891 | * Otherwise, a negative errno value is returned. |
| 892 | */ |
| 893 | int i2c_add_adapter(struct i2c_adapter *adapter) |
| 894 | { |
| 895 | int id, res = 0; |
| 896 | |
| 897 | retry: |
| 898 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) |
| 899 | return -ENOMEM; |
| 900 | |
Jean Delvare | caada32 | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 901 | mutex_lock(&core_lock); |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 902 | /* "above" here means "above or equal to", sigh */ |
| 903 | res = idr_get_new_above(&i2c_adapter_idr, adapter, |
| 904 | __i2c_first_dynamic_bus_num, &id); |
Jean Delvare | caada32 | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 905 | mutex_unlock(&core_lock); |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 906 | |
| 907 | if (res < 0) { |
| 908 | if (res == -EAGAIN) |
| 909 | goto retry; |
| 910 | return res; |
| 911 | } |
| 912 | |
| 913 | adapter->nr = id; |
| 914 | return i2c_register_adapter(adapter); |
| 915 | } |
| 916 | EXPORT_SYMBOL(i2c_add_adapter); |
| 917 | |
| 918 | /** |
| 919 | * i2c_add_numbered_adapter - declare i2c adapter, use static bus number |
| 920 | * @adap: the adapter to register (with adap->nr initialized) |
David Brownell | d64f73b | 2007-07-12 14:12:28 +0200 | [diff] [blame] | 921 | * Context: can sleep |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 922 | * |
| 923 | * This routine is used to declare an I2C adapter when its bus number |
Randy Dunlap | 8c07e46 | 2008-03-23 20:28:20 +0100 | [diff] [blame] | 924 | * matters. For example, use it for I2C adapters from system-on-chip CPUs, |
| 925 | * or otherwise built in to the system's mainboard, and where i2c_board_info |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 926 | * is used to properly configure I2C devices. |
| 927 | * |
Grant Likely | 488bf31 | 2011-07-25 17:49:43 +0200 | [diff] [blame] | 928 | * If the requested bus number is set to -1, then this function will behave |
| 929 | * identically to i2c_add_adapter, and will dynamically assign a bus number. |
| 930 | * |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 931 | * If no devices have pre-been declared for this bus, then be sure to |
| 932 | * register the adapter before any dynamically allocated ones. Otherwise |
| 933 | * the required bus ID may not be available. |
| 934 | * |
| 935 | * When this returns zero, the specified adapter became available for |
| 936 | * clients using the bus number provided in adap->nr. Also, the table |
| 937 | * of I2C devices pre-declared using i2c_register_board_info() is scanned, |
| 938 | * and the appropriate driver model device nodes are created. Otherwise, a |
| 939 | * negative errno value is returned. |
| 940 | */ |
| 941 | int i2c_add_numbered_adapter(struct i2c_adapter *adap) |
| 942 | { |
| 943 | int id; |
| 944 | int status; |
| 945 | |
Grant Likely | 488bf31 | 2011-07-25 17:49:43 +0200 | [diff] [blame] | 946 | if (adap->nr == -1) /* -1 means dynamically assign bus id */ |
| 947 | return i2c_add_adapter(adap); |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 948 | if (adap->nr & ~MAX_ID_MASK) |
| 949 | return -EINVAL; |
| 950 | |
| 951 | retry: |
| 952 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) |
| 953 | return -ENOMEM; |
| 954 | |
Jean Delvare | caada32 | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 955 | mutex_lock(&core_lock); |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 956 | /* "above" here means "above or equal to", sigh; |
| 957 | * we need the "equal to" result to force the result |
| 958 | */ |
| 959 | status = idr_get_new_above(&i2c_adapter_idr, adap, adap->nr, &id); |
| 960 | if (status == 0 && id != adap->nr) { |
| 961 | status = -EBUSY; |
| 962 | idr_remove(&i2c_adapter_idr, id); |
| 963 | } |
Jean Delvare | caada32 | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 964 | mutex_unlock(&core_lock); |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 965 | if (status == -EAGAIN) |
| 966 | goto retry; |
| 967 | |
| 968 | if (status == 0) |
| 969 | status = i2c_register_adapter(adap); |
| 970 | return status; |
| 971 | } |
| 972 | EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); |
| 973 | |
Jean Delvare | 69b0089 | 2009-12-06 17:06:27 +0100 | [diff] [blame] | 974 | static int i2c_do_del_adapter(struct i2c_driver *driver, |
| 975 | struct i2c_adapter *adapter) |
Jean Delvare | 026526f | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 976 | { |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 977 | struct i2c_client *client, *_n; |
Jean Delvare | 026526f | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 978 | int res; |
| 979 | |
Jean Delvare | acec211 | 2009-03-28 21:34:40 +0100 | [diff] [blame] | 980 | /* Remove the devices we created ourselves as the result of hardware |
| 981 | * probing (using a driver's detect method) */ |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 982 | list_for_each_entry_safe(client, _n, &driver->clients, detected) { |
| 983 | if (client->adapter == adapter) { |
| 984 | dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", |
| 985 | client->name, client->addr); |
| 986 | list_del(&client->detected); |
| 987 | i2c_unregister_device(client); |
| 988 | } |
| 989 | } |
| 990 | |
Jean Delvare | 026526f | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 991 | if (!driver->detach_adapter) |
| 992 | return 0; |
Jean Delvare | a920ff4 | 2011-04-17 10:20:19 +0200 | [diff] [blame] | 993 | dev_warn(&adapter->dev, "%s: detach_adapter method is deprecated\n", |
| 994 | driver->driver.name); |
Jean Delvare | 026526f | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 995 | res = driver->detach_adapter(adapter); |
| 996 | if (res) |
| 997 | dev_err(&adapter->dev, "detach_adapter failed (%d) " |
| 998 | "for driver [%s]\n", res, driver->driver.name); |
| 999 | return res; |
| 1000 | } |
| 1001 | |
Jean Delvare | e549c2b | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1002 | static int __unregister_client(struct device *dev, void *dummy) |
| 1003 | { |
| 1004 | struct i2c_client *client = i2c_verify_client(dev); |
Jean Delvare | 5219bf8 | 2011-01-14 22:03:49 +0100 | [diff] [blame] | 1005 | if (client && strcmp(client->name, "dummy")) |
| 1006 | i2c_unregister_device(client); |
| 1007 | return 0; |
| 1008 | } |
| 1009 | |
| 1010 | static int __unregister_dummy(struct device *dev, void *dummy) |
| 1011 | { |
| 1012 | struct i2c_client *client = i2c_verify_client(dev); |
Jean Delvare | e549c2b | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1013 | if (client) |
| 1014 | i2c_unregister_device(client); |
| 1015 | return 0; |
| 1016 | } |
| 1017 | |
Jean Delvare | 69b0089 | 2009-12-06 17:06:27 +0100 | [diff] [blame] | 1018 | static int __process_removed_adapter(struct device_driver *d, void *data) |
| 1019 | { |
| 1020 | return i2c_do_del_adapter(to_i2c_driver(d), data); |
| 1021 | } |
| 1022 | |
David Brownell | d64f73b | 2007-07-12 14:12:28 +0200 | [diff] [blame] | 1023 | /** |
| 1024 | * i2c_del_adapter - unregister I2C adapter |
| 1025 | * @adap: the adapter being unregistered |
| 1026 | * Context: can sleep |
| 1027 | * |
| 1028 | * This unregisters an I2C adapter which was previously registered |
| 1029 | * by @i2c_add_adapter or @i2c_add_numbered_adapter. |
| 1030 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1031 | int i2c_del_adapter(struct i2c_adapter *adap) |
| 1032 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1033 | int res = 0; |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1034 | struct i2c_adapter *found; |
Jean Delvare | bbd2d9c | 2009-11-26 09:22:33 +0100 | [diff] [blame] | 1035 | struct i2c_client *client, *next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1036 | |
| 1037 | /* First make sure that this adapter was ever added */ |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1038 | mutex_lock(&core_lock); |
| 1039 | found = idr_find(&i2c_adapter_idr, adap->nr); |
| 1040 | mutex_unlock(&core_lock); |
| 1041 | if (found != adap) { |
Jean Delvare | b6d7b3d | 2005-07-31 19:02:53 +0200 | [diff] [blame] | 1042 | pr_debug("i2c-core: attempting to delete unregistered " |
| 1043 | "adapter [%s]\n", adap->name); |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1044 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1045 | } |
| 1046 | |
Jean Delvare | 026526f | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 1047 | /* Tell drivers about this removal */ |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1048 | mutex_lock(&core_lock); |
Jean Delvare | 026526f | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 1049 | res = bus_for_each_drv(&i2c_bus_type, NULL, adap, |
Jean Delvare | 69b0089 | 2009-12-06 17:06:27 +0100 | [diff] [blame] | 1050 | __process_removed_adapter); |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1051 | mutex_unlock(&core_lock); |
Jean Delvare | 026526f | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 1052 | if (res) |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1053 | return res; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1054 | |
Jean Delvare | bbd2d9c | 2009-11-26 09:22:33 +0100 | [diff] [blame] | 1055 | /* Remove devices instantiated from sysfs */ |
Jean Delvare | dafc50d | 2010-08-11 18:21:01 +0200 | [diff] [blame] | 1056 | mutex_lock(&adap->userspace_clients_lock); |
Jean Delvare | 6629dcf | 2010-05-04 11:09:28 +0200 | [diff] [blame] | 1057 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
| 1058 | detected) { |
| 1059 | dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, |
| 1060 | client->addr); |
| 1061 | list_del(&client->detected); |
| 1062 | i2c_unregister_device(client); |
Jean Delvare | bbd2d9c | 2009-11-26 09:22:33 +0100 | [diff] [blame] | 1063 | } |
Jean Delvare | dafc50d | 2010-08-11 18:21:01 +0200 | [diff] [blame] | 1064 | mutex_unlock(&adap->userspace_clients_lock); |
Jean Delvare | bbd2d9c | 2009-11-26 09:22:33 +0100 | [diff] [blame] | 1065 | |
Jean Delvare | e549c2b | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1066 | /* Detach any active clients. This can't fail, thus we do not |
Jean Delvare | 5219bf8 | 2011-01-14 22:03:49 +0100 | [diff] [blame] | 1067 | * check the returned value. This is a two-pass process, because |
| 1068 | * we can't remove the dummy devices during the first pass: they |
| 1069 | * could have been instantiated by real devices wishing to clean |
| 1070 | * them up properly, so we give them a chance to do that first. */ |
Jean Delvare | e549c2b | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1071 | res = device_for_each_child(&adap->dev, NULL, __unregister_client); |
Jean Delvare | 5219bf8 | 2011-01-14 22:03:49 +0100 | [diff] [blame] | 1072 | res = device_for_each_child(&adap->dev, NULL, __unregister_dummy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1073 | |
Jean Delvare | 2bb5095 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 1074 | #ifdef CONFIG_I2C_COMPAT |
| 1075 | class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, |
| 1076 | adap->dev.parent); |
| 1077 | #endif |
| 1078 | |
Thadeu Lima de Souza Cascardo | c556752 | 2010-01-16 20:43:13 +0100 | [diff] [blame] | 1079 | /* device name is gone after device_unregister */ |
| 1080 | dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); |
| 1081 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1082 | /* clean up the sysfs representation */ |
| 1083 | init_completion(&adap->dev_released); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1084 | device_unregister(&adap->dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1085 | |
| 1086 | /* wait for sysfs to drop all references */ |
| 1087 | wait_for_completion(&adap->dev_released); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1088 | |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1089 | /* free bus id */ |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1090 | mutex_lock(&core_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1091 | idr_remove(&i2c_adapter_idr, adap->nr); |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1092 | mutex_unlock(&core_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1093 | |
Jean Delvare | bd4bc3db | 2008-07-16 19:30:05 +0200 | [diff] [blame] | 1094 | /* Clear the device structure in case this adapter is ever going to be |
| 1095 | added again */ |
| 1096 | memset(&adap->dev, 0, sizeof(adap->dev)); |
| 1097 | |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1098 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1099 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1100 | EXPORT_SYMBOL(i2c_del_adapter); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1101 | |
| 1102 | |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 1103 | /* ------------------------------------------------------------------------- */ |
| 1104 | |
Jean Delvare | 7ae3148 | 2011-03-20 14:50:52 +0100 | [diff] [blame] | 1105 | int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *)) |
| 1106 | { |
| 1107 | int res; |
| 1108 | |
| 1109 | mutex_lock(&core_lock); |
| 1110 | res = bus_for_each_dev(&i2c_bus_type, NULL, data, fn); |
| 1111 | mutex_unlock(&core_lock); |
| 1112 | |
| 1113 | return res; |
| 1114 | } |
| 1115 | EXPORT_SYMBOL_GPL(i2c_for_each_dev); |
| 1116 | |
Jean Delvare | 69b0089 | 2009-12-06 17:06:27 +0100 | [diff] [blame] | 1117 | static int __process_new_driver(struct device *dev, void *data) |
Dave Young | 7f101a9 | 2008-07-14 22:38:19 +0200 | [diff] [blame] | 1118 | { |
Jean Delvare | 4f8cf82 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 1119 | if (dev->type != &i2c_adapter_type) |
| 1120 | return 0; |
Jean Delvare | 69b0089 | 2009-12-06 17:06:27 +0100 | [diff] [blame] | 1121 | return i2c_do_add_adapter(data, to_i2c_adapter(dev)); |
Dave Young | 7f101a9 | 2008-07-14 22:38:19 +0200 | [diff] [blame] | 1122 | } |
| 1123 | |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 1124 | /* |
| 1125 | * An i2c_driver is used with one or more i2c_client (device) nodes to access |
Jean Delvare | 729d6dd | 2009-06-19 16:58:18 +0200 | [diff] [blame] | 1126 | * i2c slave chips, on a bus instance associated with some i2c_adapter. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1127 | */ |
| 1128 | |
Greg Kroah-Hartman | de59cf9 | 2005-12-06 15:33:15 -0800 | [diff] [blame] | 1129 | int i2c_register_driver(struct module *owner, struct i2c_driver *driver) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1130 | { |
Jean Delvare | 7eebcb7 | 2006-02-05 23:28:21 +0100 | [diff] [blame] | 1131 | int res; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1132 | |
David Brownell | 1d0b19c | 2008-10-14 17:30:05 +0200 | [diff] [blame] | 1133 | /* Can't register until after driver model init */ |
| 1134 | if (unlikely(WARN_ON(!i2c_bus_type.p))) |
| 1135 | return -EAGAIN; |
| 1136 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1137 | /* add the driver to the list of i2c drivers in the driver core */ |
Greg Kroah-Hartman | de59cf9 | 2005-12-06 15:33:15 -0800 | [diff] [blame] | 1138 | driver->driver.owner = owner; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1139 | driver->driver.bus = &i2c_bus_type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1140 | |
Jean Delvare | 729d6dd | 2009-06-19 16:58:18 +0200 | [diff] [blame] | 1141 | /* When registration returns, the driver core |
David Brownell | 6e13e64 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1142 | * will have called probe() for all matching-but-unbound devices. |
| 1143 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1144 | res = driver_register(&driver->driver); |
| 1145 | if (res) |
Jean Delvare | 7eebcb7 | 2006-02-05 23:28:21 +0100 | [diff] [blame] | 1146 | return res; |
David Brownell | 438d6c2 | 2006-12-10 21:21:31 +0100 | [diff] [blame] | 1147 | |
Mark Brown | f4e8db3 | 2011-01-14 22:03:50 +0100 | [diff] [blame] | 1148 | /* Drivers should switch to dev_pm_ops instead. */ |
| 1149 | if (driver->suspend) |
| 1150 | pr_warn("i2c-core: driver [%s] using legacy suspend method\n", |
| 1151 | driver->driver.name); |
| 1152 | if (driver->resume) |
| 1153 | pr_warn("i2c-core: driver [%s] using legacy resume method\n", |
| 1154 | driver->driver.name); |
| 1155 | |
Laurent Riffard | 35d8b2e | 2005-11-26 20:34:05 +0100 | [diff] [blame] | 1156 | pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1157 | |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 1158 | INIT_LIST_HEAD(&driver->clients); |
| 1159 | /* Walk the adapters that are already present */ |
Jean Delvare | 7ae3148 | 2011-03-20 14:50:52 +0100 | [diff] [blame] | 1160 | i2c_for_each_dev(driver, __process_new_driver); |
Jean Delvare | 35fc37f | 2009-06-19 16:58:19 +0200 | [diff] [blame] | 1161 | |
Jean Delvare | 7eebcb7 | 2006-02-05 23:28:21 +0100 | [diff] [blame] | 1162 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1163 | } |
Greg Kroah-Hartman | de59cf9 | 2005-12-06 15:33:15 -0800 | [diff] [blame] | 1164 | EXPORT_SYMBOL(i2c_register_driver); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1165 | |
Jean Delvare | 69b0089 | 2009-12-06 17:06:27 +0100 | [diff] [blame] | 1166 | static int __process_removed_driver(struct device *dev, void *data) |
Dave Young | 7f101a9 | 2008-07-14 22:38:19 +0200 | [diff] [blame] | 1167 | { |
Jean Delvare | 4f8cf82 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 1168 | if (dev->type != &i2c_adapter_type) |
| 1169 | return 0; |
Jean Delvare | 69b0089 | 2009-12-06 17:06:27 +0100 | [diff] [blame] | 1170 | return i2c_do_del_adapter(data, to_i2c_adapter(dev)); |
Dave Young | 7f101a9 | 2008-07-14 22:38:19 +0200 | [diff] [blame] | 1171 | } |
| 1172 | |
David Brownell | a1d9e6e | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 1173 | /** |
| 1174 | * i2c_del_driver - unregister I2C driver |
| 1175 | * @driver: the driver being unregistered |
David Brownell | d64f73b | 2007-07-12 14:12:28 +0200 | [diff] [blame] | 1176 | * Context: can sleep |
David Brownell | a1d9e6e | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 1177 | */ |
Jean Delvare | b3e8209 | 2007-05-01 23:26:32 +0200 | [diff] [blame] | 1178 | void i2c_del_driver(struct i2c_driver *driver) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1179 | { |
Jean Delvare | 7ae3148 | 2011-03-20 14:50:52 +0100 | [diff] [blame] | 1180 | i2c_for_each_dev(driver, __process_removed_driver); |
David Brownell | a1d9e6e | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 1181 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1182 | driver_unregister(&driver->driver); |
Laurent Riffard | 35d8b2e | 2005-11-26 20:34:05 +0100 | [diff] [blame] | 1183 | pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1184 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1185 | EXPORT_SYMBOL(i2c_del_driver); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1186 | |
David Brownell | 7b4fbc5 | 2007-05-01 23:26:30 +0200 | [diff] [blame] | 1187 | /* ------------------------------------------------------------------------- */ |
| 1188 | |
Jean Delvare | e48d331 | 2008-01-27 18:14:48 +0100 | [diff] [blame] | 1189 | /** |
| 1190 | * i2c_use_client - increments the reference count of the i2c client structure |
| 1191 | * @client: the client being referenced |
| 1192 | * |
| 1193 | * Each live reference to a client should be refcounted. The driver model does |
| 1194 | * that automatically as part of driver binding, so that most drivers don't |
| 1195 | * need to do this explicitly: they hold a reference until they're unbound |
| 1196 | * from the device. |
| 1197 | * |
| 1198 | * A pointer to the client with the incremented reference counter is returned. |
| 1199 | */ |
| 1200 | struct i2c_client *i2c_use_client(struct i2c_client *client) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1201 | { |
David Brownell | 6ea438e | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1202 | if (client && get_device(&client->dev)) |
| 1203 | return client; |
| 1204 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1205 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1206 | EXPORT_SYMBOL(i2c_use_client); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1207 | |
Jean Delvare | e48d331 | 2008-01-27 18:14:48 +0100 | [diff] [blame] | 1208 | /** |
| 1209 | * i2c_release_client - release a use of the i2c client structure |
| 1210 | * @client: the client being no longer referenced |
| 1211 | * |
| 1212 | * Must be called when a user of a client is finished with it. |
| 1213 | */ |
| 1214 | void i2c_release_client(struct i2c_client *client) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1215 | { |
David Brownell | 6ea438e | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1216 | if (client) |
| 1217 | put_device(&client->dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1218 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1219 | EXPORT_SYMBOL(i2c_release_client); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1220 | |
David Brownell | 9b766b8 | 2008-01-27 18:14:51 +0100 | [diff] [blame] | 1221 | struct i2c_cmd_arg { |
| 1222 | unsigned cmd; |
| 1223 | void *arg; |
| 1224 | }; |
| 1225 | |
| 1226 | static int i2c_cmd(struct device *dev, void *_arg) |
| 1227 | { |
| 1228 | struct i2c_client *client = i2c_verify_client(dev); |
| 1229 | struct i2c_cmd_arg *arg = _arg; |
| 1230 | |
| 1231 | if (client && client->driver && client->driver->command) |
| 1232 | client->driver->command(client, arg->cmd, arg->arg); |
| 1233 | return 0; |
| 1234 | } |
| 1235 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1236 | void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) |
| 1237 | { |
David Brownell | 9b766b8 | 2008-01-27 18:14:51 +0100 | [diff] [blame] | 1238 | struct i2c_cmd_arg cmd_arg; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1239 | |
David Brownell | 9b766b8 | 2008-01-27 18:14:51 +0100 | [diff] [blame] | 1240 | cmd_arg.cmd = cmd; |
| 1241 | cmd_arg.arg = arg; |
| 1242 | device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1243 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1244 | EXPORT_SYMBOL(i2c_clients_command); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1245 | |
| 1246 | static int __init i2c_init(void) |
| 1247 | { |
| 1248 | int retval; |
| 1249 | |
| 1250 | retval = bus_register(&i2c_bus_type); |
| 1251 | if (retval) |
| 1252 | return retval; |
Jean Delvare | 2bb5095 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 1253 | #ifdef CONFIG_I2C_COMPAT |
| 1254 | i2c_adapter_compat_class = class_compat_register("i2c-adapter"); |
| 1255 | if (!i2c_adapter_compat_class) { |
| 1256 | retval = -ENOMEM; |
| 1257 | goto bus_err; |
| 1258 | } |
| 1259 | #endif |
David Brownell | e9f1373 | 2008-01-27 18:14:52 +0100 | [diff] [blame] | 1260 | retval = i2c_add_driver(&dummy_driver); |
| 1261 | if (retval) |
Jean Delvare | 2bb5095 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 1262 | goto class_err; |
David Brownell | e9f1373 | 2008-01-27 18:14:52 +0100 | [diff] [blame] | 1263 | return 0; |
| 1264 | |
Jean Delvare | 2bb5095 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 1265 | class_err: |
| 1266 | #ifdef CONFIG_I2C_COMPAT |
| 1267 | class_compat_unregister(i2c_adapter_compat_class); |
David Brownell | e9f1373 | 2008-01-27 18:14:52 +0100 | [diff] [blame] | 1268 | bus_err: |
Jean Delvare | 2bb5095 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 1269 | #endif |
David Brownell | e9f1373 | 2008-01-27 18:14:52 +0100 | [diff] [blame] | 1270 | bus_unregister(&i2c_bus_type); |
| 1271 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1272 | } |
| 1273 | |
| 1274 | static void __exit i2c_exit(void) |
| 1275 | { |
David Brownell | e9f1373 | 2008-01-27 18:14:52 +0100 | [diff] [blame] | 1276 | i2c_del_driver(&dummy_driver); |
Jean Delvare | 2bb5095 | 2009-09-18 22:45:46 +0200 | [diff] [blame] | 1277 | #ifdef CONFIG_I2C_COMPAT |
| 1278 | class_compat_unregister(i2c_adapter_compat_class); |
| 1279 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1280 | bus_unregister(&i2c_bus_type); |
| 1281 | } |
| 1282 | |
David Brownell | a10f9e7 | 2008-10-14 17:30:06 +0200 | [diff] [blame] | 1283 | /* We must initialize early, because some subsystems register i2c drivers |
| 1284 | * in subsys_initcall() code, but are linked (and initialized) before i2c. |
| 1285 | */ |
| 1286 | postcore_initcall(i2c_init); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1287 | module_exit(i2c_exit); |
| 1288 | |
| 1289 | /* ---------------------------------------------------- |
| 1290 | * the functional interface to the i2c busses. |
| 1291 | * ---------------------------------------------------- |
| 1292 | */ |
| 1293 | |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1294 | /** |
| 1295 | * i2c_transfer - execute a single or combined I2C message |
| 1296 | * @adap: Handle to I2C bus |
| 1297 | * @msgs: One or more messages to execute before STOP is issued to |
| 1298 | * terminate the operation; each message begins with a START. |
| 1299 | * @num: Number of messages to be executed. |
| 1300 | * |
| 1301 | * Returns negative errno, else the number of messages executed. |
| 1302 | * |
| 1303 | * Note that there is no requirement that each message be sent to |
| 1304 | * the same slave address, although that is the most common model. |
| 1305 | */ |
Zhenwen Xu | 09b8ce0 | 2009-03-28 21:34:46 +0100 | [diff] [blame] | 1306 | int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1307 | { |
Clifford Wolf | 66b650f | 2009-06-15 18:01:46 +0200 | [diff] [blame] | 1308 | unsigned long orig_jiffies; |
| 1309 | int ret, try; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1310 | |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1311 | /* REVISIT the fault reporting model here is weak: |
| 1312 | * |
| 1313 | * - When we get an error after receiving N bytes from a slave, |
| 1314 | * there is no way to report "N". |
| 1315 | * |
| 1316 | * - When we get a NAK after transmitting N bytes to a slave, |
| 1317 | * there is no way to report "N" ... or to let the master |
| 1318 | * continue executing the rest of this combined message, if |
| 1319 | * that's the appropriate response. |
| 1320 | * |
| 1321 | * - When for example "num" is two and we successfully complete |
| 1322 | * the first message but get an error part way through the |
| 1323 | * second, it's unclear whether that should be reported as |
| 1324 | * one (discarding status on the second message) or errno |
| 1325 | * (discarding status on the first one). |
| 1326 | */ |
| 1327 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1328 | if (adap->algo->master_xfer) { |
| 1329 | #ifdef DEBUG |
| 1330 | for (ret = 0; ret < num; ret++) { |
| 1331 | dev_dbg(&adap->dev, "master_xfer[%d] %c, addr=0x%02x, " |
Jean Delvare | 209d27c | 2007-05-01 23:26:29 +0200 | [diff] [blame] | 1332 | "len=%d%s\n", ret, (msgs[ret].flags & I2C_M_RD) |
| 1333 | ? 'R' : 'W', msgs[ret].addr, msgs[ret].len, |
| 1334 | (msgs[ret].flags & I2C_M_RECV_LEN) ? "+" : ""); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1335 | } |
| 1336 | #endif |
| 1337 | |
Mike Rapoport | cea443a | 2008-01-27 18:14:50 +0100 | [diff] [blame] | 1338 | if (in_atomic() || irqs_disabled()) { |
Jean Delvare | fe61e07 | 2010-08-11 18:20:58 +0200 | [diff] [blame] | 1339 | ret = i2c_trylock_adapter(adap); |
Mike Rapoport | cea443a | 2008-01-27 18:14:50 +0100 | [diff] [blame] | 1340 | if (!ret) |
| 1341 | /* I2C activity is ongoing. */ |
| 1342 | return -EAGAIN; |
| 1343 | } else { |
Jean Delvare | fe61e07 | 2010-08-11 18:20:58 +0200 | [diff] [blame] | 1344 | i2c_lock_adapter(adap); |
Mike Rapoport | cea443a | 2008-01-27 18:14:50 +0100 | [diff] [blame] | 1345 | } |
| 1346 | |
Clifford Wolf | 66b650f | 2009-06-15 18:01:46 +0200 | [diff] [blame] | 1347 | /* Retry automatically on arbitration loss */ |
| 1348 | orig_jiffies = jiffies; |
| 1349 | for (ret = 0, try = 0; try <= adap->retries; try++) { |
| 1350 | ret = adap->algo->master_xfer(adap, msgs, num); |
| 1351 | if (ret != -EAGAIN) |
| 1352 | break; |
| 1353 | if (time_after(jiffies, orig_jiffies + adap->timeout)) |
| 1354 | break; |
| 1355 | } |
Jean Delvare | fe61e07 | 2010-08-11 18:20:58 +0200 | [diff] [blame] | 1356 | i2c_unlock_adapter(adap); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1357 | |
| 1358 | return ret; |
| 1359 | } else { |
| 1360 | dev_dbg(&adap->dev, "I2C level transfers not supported\n"); |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 1361 | return -EOPNOTSUPP; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1362 | } |
| 1363 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1364 | EXPORT_SYMBOL(i2c_transfer); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1365 | |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1366 | /** |
| 1367 | * i2c_master_send - issue a single I2C message in master transmit mode |
| 1368 | * @client: Handle to slave device |
| 1369 | * @buf: Data that will be written to the slave |
Zhangfei Gao | 0c43ea5 | 2010-03-02 12:23:49 +0100 | [diff] [blame] | 1370 | * @count: How many bytes to write, must be less than 64k since msg.len is u16 |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1371 | * |
| 1372 | * Returns negative errno, or else the number of bytes written. |
| 1373 | */ |
Jean Delvare | 0cc43a1 | 2011-01-10 22:11:23 +0100 | [diff] [blame] | 1374 | int i2c_master_send(const struct i2c_client *client, const char *buf, int count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1375 | { |
| 1376 | int ret; |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 1377 | struct i2c_adapter *adap = client->adapter; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1378 | struct i2c_msg msg; |
| 1379 | |
Jean Delvare | 815f55f | 2005-05-07 22:58:46 +0200 | [diff] [blame] | 1380 | msg.addr = client->addr; |
| 1381 | msg.flags = client->flags & I2C_M_TEN; |
| 1382 | msg.len = count; |
| 1383 | msg.buf = (char *)buf; |
David Brownell | 438d6c2 | 2006-12-10 21:21:31 +0100 | [diff] [blame] | 1384 | |
Jean Delvare | 815f55f | 2005-05-07 22:58:46 +0200 | [diff] [blame] | 1385 | ret = i2c_transfer(adap, &msg, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1386 | |
Jean Delvare | 815f55f | 2005-05-07 22:58:46 +0200 | [diff] [blame] | 1387 | /* If everything went ok (i.e. 1 msg transmitted), return #bytes |
| 1388 | transmitted, else error code. */ |
| 1389 | return (ret == 1) ? count : ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1390 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1391 | EXPORT_SYMBOL(i2c_master_send); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1392 | |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1393 | /** |
| 1394 | * i2c_master_recv - issue a single I2C message in master receive mode |
| 1395 | * @client: Handle to slave device |
| 1396 | * @buf: Where to store data read from slave |
Zhangfei Gao | 0c43ea5 | 2010-03-02 12:23:49 +0100 | [diff] [blame] | 1397 | * @count: How many bytes to read, must be less than 64k since msg.len is u16 |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1398 | * |
| 1399 | * Returns negative errno, or else the number of bytes read. |
| 1400 | */ |
Jean Delvare | 0cc43a1 | 2011-01-10 22:11:23 +0100 | [diff] [blame] | 1401 | int i2c_master_recv(const struct i2c_client *client, char *buf, int count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1402 | { |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 1403 | struct i2c_adapter *adap = client->adapter; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1404 | struct i2c_msg msg; |
| 1405 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1406 | |
Jean Delvare | 815f55f | 2005-05-07 22:58:46 +0200 | [diff] [blame] | 1407 | msg.addr = client->addr; |
| 1408 | msg.flags = client->flags & I2C_M_TEN; |
| 1409 | msg.flags |= I2C_M_RD; |
| 1410 | msg.len = count; |
| 1411 | msg.buf = buf; |
| 1412 | |
| 1413 | ret = i2c_transfer(adap, &msg, 1); |
| 1414 | |
| 1415 | /* If everything went ok (i.e. 1 msg transmitted), return #bytes |
| 1416 | transmitted, else error code. */ |
| 1417 | return (ret == 1) ? count : ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1418 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1419 | EXPORT_SYMBOL(i2c_master_recv); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1420 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1421 | /* ---------------------------------------------------- |
| 1422 | * the i2c address scanning function |
| 1423 | * Will not work for 10-bit addresses! |
| 1424 | * ---------------------------------------------------- |
| 1425 | */ |
Jean Delvare | 9fc6adf | 2005-07-31 21:20:43 +0200 | [diff] [blame] | 1426 | |
Jean Delvare | 63e4e80 | 2010-06-03 11:33:51 +0200 | [diff] [blame] | 1427 | /* |
| 1428 | * Legacy default probe function, mostly relevant for SMBus. The default |
| 1429 | * probe method is a quick write, but it is known to corrupt the 24RF08 |
| 1430 | * EEPROMs due to a state machine bug, and could also irreversibly |
| 1431 | * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f, |
| 1432 | * we use a short byte read instead. Also, some bus drivers don't implement |
| 1433 | * quick write, so we fallback to a byte read in that case too. |
| 1434 | * On x86, there is another special case for FSC hardware monitoring chips, |
| 1435 | * which want regular byte reads (address 0x73.) Fortunately, these are the |
| 1436 | * only known chips using this I2C address on PC hardware. |
| 1437 | * Returns 1 if probe succeeded, 0 if not. |
| 1438 | */ |
| 1439 | static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) |
| 1440 | { |
| 1441 | int err; |
| 1442 | union i2c_smbus_data dummy; |
| 1443 | |
| 1444 | #ifdef CONFIG_X86 |
| 1445 | if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON) |
| 1446 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA)) |
| 1447 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, |
| 1448 | I2C_SMBUS_BYTE_DATA, &dummy); |
| 1449 | else |
| 1450 | #endif |
Jean Delvare | 8031d79 | 2010-08-11 18:21:00 +0200 | [diff] [blame] | 1451 | if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50) |
| 1452 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) |
Jean Delvare | 63e4e80 | 2010-06-03 11:33:51 +0200 | [diff] [blame] | 1453 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, |
| 1454 | I2C_SMBUS_QUICK, NULL); |
Jean Delvare | 8031d79 | 2010-08-11 18:21:00 +0200 | [diff] [blame] | 1455 | else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) |
| 1456 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, |
| 1457 | I2C_SMBUS_BYTE, &dummy); |
| 1458 | else { |
| 1459 | dev_warn(&adap->dev, "No suitable probing method supported\n"); |
| 1460 | err = -EOPNOTSUPP; |
| 1461 | } |
Jean Delvare | 63e4e80 | 2010-06-03 11:33:51 +0200 | [diff] [blame] | 1462 | |
| 1463 | return err >= 0; |
| 1464 | } |
| 1465 | |
Jean Delvare | ccfbbd0 | 2009-12-06 17:06:25 +0100 | [diff] [blame] | 1466 | static int i2c_detect_address(struct i2c_client *temp_client, |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 1467 | struct i2c_driver *driver) |
| 1468 | { |
| 1469 | struct i2c_board_info info; |
| 1470 | struct i2c_adapter *adapter = temp_client->adapter; |
| 1471 | int addr = temp_client->addr; |
| 1472 | int err; |
| 1473 | |
| 1474 | /* Make sure the address is valid */ |
Jean Delvare | 656b876 | 2010-06-03 11:33:53 +0200 | [diff] [blame] | 1475 | err = i2c_check_addr_validity(addr); |
| 1476 | if (err) { |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 1477 | dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", |
| 1478 | addr); |
Jean Delvare | 656b876 | 2010-06-03 11:33:53 +0200 | [diff] [blame] | 1479 | return err; |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 1480 | } |
| 1481 | |
| 1482 | /* Skip if already in use */ |
Jean Delvare | 3b5f794 | 2010-06-03 11:33:55 +0200 | [diff] [blame] | 1483 | if (i2c_check_addr_busy(adapter, addr)) |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 1484 | return 0; |
| 1485 | |
Jean Delvare | ccfbbd0 | 2009-12-06 17:06:25 +0100 | [diff] [blame] | 1486 | /* Make sure there is something at this address */ |
Jean Delvare | 63e4e80 | 2010-06-03 11:33:51 +0200 | [diff] [blame] | 1487 | if (!i2c_default_probe(adapter, addr)) |
| 1488 | return 0; |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 1489 | |
| 1490 | /* Finally call the custom detection function */ |
| 1491 | memset(&info, 0, sizeof(struct i2c_board_info)); |
| 1492 | info.addr = addr; |
Jean Delvare | 310ec79 | 2009-12-14 21:17:23 +0100 | [diff] [blame] | 1493 | err = driver->detect(temp_client, &info); |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 1494 | if (err) { |
| 1495 | /* -ENODEV is returned if the detection fails. We catch it |
| 1496 | here as this isn't an error. */ |
| 1497 | return err == -ENODEV ? 0 : err; |
| 1498 | } |
| 1499 | |
| 1500 | /* Consistency check */ |
| 1501 | if (info.type[0] == '\0') { |
| 1502 | dev_err(&adapter->dev, "%s detection function provided " |
| 1503 | "no name for 0x%x\n", driver->driver.name, |
| 1504 | addr); |
| 1505 | } else { |
| 1506 | struct i2c_client *client; |
| 1507 | |
| 1508 | /* Detection succeeded, instantiate the device */ |
| 1509 | dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n", |
| 1510 | info.type, info.addr); |
| 1511 | client = i2c_new_device(adapter, &info); |
| 1512 | if (client) |
| 1513 | list_add_tail(&client->detected, &driver->clients); |
| 1514 | else |
| 1515 | dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n", |
| 1516 | info.type, info.addr); |
| 1517 | } |
| 1518 | return 0; |
| 1519 | } |
| 1520 | |
| 1521 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) |
| 1522 | { |
Jean Delvare | c3813d6 | 2009-12-14 21:17:25 +0100 | [diff] [blame] | 1523 | const unsigned short *address_list; |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 1524 | struct i2c_client *temp_client; |
| 1525 | int i, err = 0; |
| 1526 | int adap_id = i2c_adapter_id(adapter); |
| 1527 | |
Jean Delvare | c3813d6 | 2009-12-14 21:17:25 +0100 | [diff] [blame] | 1528 | address_list = driver->address_list; |
| 1529 | if (!driver->detect || !address_list) |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 1530 | return 0; |
| 1531 | |
Jean Delvare | 51b54ba | 2010-10-24 18:16:58 +0200 | [diff] [blame] | 1532 | /* Stop here if the classes do not match */ |
| 1533 | if (!(adapter->class & driver->class)) |
| 1534 | return 0; |
| 1535 | |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 1536 | /* Set up a temporary client to help detect callback */ |
| 1537 | temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); |
| 1538 | if (!temp_client) |
| 1539 | return -ENOMEM; |
| 1540 | temp_client->adapter = adapter; |
| 1541 | |
Jean Delvare | c3813d6 | 2009-12-14 21:17:25 +0100 | [diff] [blame] | 1542 | for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 1543 | dev_dbg(&adapter->dev, "found normal entry for adapter %d, " |
Jean Delvare | c3813d6 | 2009-12-14 21:17:25 +0100 | [diff] [blame] | 1544 | "addr 0x%02x\n", adap_id, address_list[i]); |
| 1545 | temp_client->addr = address_list[i]; |
Jean Delvare | ccfbbd0 | 2009-12-06 17:06:25 +0100 | [diff] [blame] | 1546 | err = i2c_detect_address(temp_client, driver); |
Jean Delvare | 51b54ba | 2010-10-24 18:16:58 +0200 | [diff] [blame] | 1547 | if (unlikely(err)) |
| 1548 | break; |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 1549 | } |
| 1550 | |
Jean Delvare | 4735c98 | 2008-07-14 22:38:36 +0200 | [diff] [blame] | 1551 | kfree(temp_client); |
| 1552 | return err; |
| 1553 | } |
| 1554 | |
Jean Delvare | d44f19d | 2010-08-11 18:20:57 +0200 | [diff] [blame] | 1555 | int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) |
| 1556 | { |
| 1557 | return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, |
| 1558 | I2C_SMBUS_QUICK, NULL) >= 0; |
| 1559 | } |
| 1560 | EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); |
| 1561 | |
Jean Delvare | 12b5053a | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1562 | struct i2c_client * |
| 1563 | i2c_new_probed_device(struct i2c_adapter *adap, |
| 1564 | struct i2c_board_info *info, |
Jean Delvare | 9a94241 | 2010-08-11 18:20:56 +0200 | [diff] [blame] | 1565 | unsigned short const *addr_list, |
| 1566 | int (*probe)(struct i2c_adapter *, unsigned short addr)) |
Jean Delvare | 12b5053a | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1567 | { |
| 1568 | int i; |
| 1569 | |
Jean Delvare | 8031d79 | 2010-08-11 18:21:00 +0200 | [diff] [blame] | 1570 | if (!probe) |
Jean Delvare | 9a94241 | 2010-08-11 18:20:56 +0200 | [diff] [blame] | 1571 | probe = i2c_default_probe; |
Jean Delvare | 12b5053a | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1572 | |
Jean Delvare | 12b5053a | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1573 | for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { |
| 1574 | /* Check address validity */ |
Jean Delvare | 656b876 | 2010-06-03 11:33:53 +0200 | [diff] [blame] | 1575 | if (i2c_check_addr_validity(addr_list[i]) < 0) { |
Jean Delvare | 12b5053a | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1576 | dev_warn(&adap->dev, "Invalid 7-bit address " |
| 1577 | "0x%02x\n", addr_list[i]); |
| 1578 | continue; |
| 1579 | } |
| 1580 | |
| 1581 | /* Check address availability */ |
Jean Delvare | 3b5f794 | 2010-06-03 11:33:55 +0200 | [diff] [blame] | 1582 | if (i2c_check_addr_busy(adap, addr_list[i])) { |
Jean Delvare | 12b5053a | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1583 | dev_dbg(&adap->dev, "Address 0x%02x already in " |
| 1584 | "use, not probing\n", addr_list[i]); |
| 1585 | continue; |
| 1586 | } |
| 1587 | |
Jean Delvare | 63e4e80 | 2010-06-03 11:33:51 +0200 | [diff] [blame] | 1588 | /* Test address responsiveness */ |
Jean Delvare | 9a94241 | 2010-08-11 18:20:56 +0200 | [diff] [blame] | 1589 | if (probe(adap, addr_list[i])) |
Jean Delvare | 63e4e80 | 2010-06-03 11:33:51 +0200 | [diff] [blame] | 1590 | break; |
Jean Delvare | 12b5053a | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1591 | } |
Jean Delvare | 12b5053a | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1592 | |
| 1593 | if (addr_list[i] == I2C_CLIENT_END) { |
| 1594 | dev_dbg(&adap->dev, "Probing failed, no device found\n"); |
| 1595 | return NULL; |
| 1596 | } |
| 1597 | |
| 1598 | info->addr = addr_list[i]; |
| 1599 | return i2c_new_device(adap, info); |
| 1600 | } |
| 1601 | EXPORT_SYMBOL_GPL(i2c_new_probed_device); |
| 1602 | |
Jean Delvare | d735b34 | 2011-03-20 14:50:52 +0100 | [diff] [blame] | 1603 | struct i2c_adapter *i2c_get_adapter(int nr) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1604 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1605 | struct i2c_adapter *adapter; |
David Brownell | 438d6c2 | 2006-12-10 21:21:31 +0100 | [diff] [blame] | 1606 | |
Jean Delvare | caada32 | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 1607 | mutex_lock(&core_lock); |
Jean Delvare | d735b34 | 2011-03-20 14:50:52 +0100 | [diff] [blame] | 1608 | adapter = idr_find(&i2c_adapter_idr, nr); |
Mark M. Hoffman | a0920e1 | 2005-06-28 00:21:30 -0400 | [diff] [blame] | 1609 | if (adapter && !try_module_get(adapter->owner)) |
| 1610 | adapter = NULL; |
| 1611 | |
Jean Delvare | caada32 | 2008-01-27 18:14:49 +0100 | [diff] [blame] | 1612 | mutex_unlock(&core_lock); |
Mark M. Hoffman | a0920e1 | 2005-06-28 00:21:30 -0400 | [diff] [blame] | 1613 | return adapter; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1614 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1615 | EXPORT_SYMBOL(i2c_get_adapter); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1616 | |
| 1617 | void i2c_put_adapter(struct i2c_adapter *adap) |
| 1618 | { |
| 1619 | module_put(adap->owner); |
| 1620 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1621 | EXPORT_SYMBOL(i2c_put_adapter); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1622 | |
| 1623 | /* The SMBus parts */ |
| 1624 | |
David Brownell | 438d6c2 | 2006-12-10 21:21:31 +0100 | [diff] [blame] | 1625 | #define POLY (0x1070U << 3) |
Zhenwen Xu | 09b8ce0 | 2009-03-28 21:34:46 +0100 | [diff] [blame] | 1626 | static u8 crc8(u16 data) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1627 | { |
| 1628 | int i; |
David Brownell | 438d6c2 | 2006-12-10 21:21:31 +0100 | [diff] [blame] | 1629 | |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 1630 | for (i = 0; i < 8; i++) { |
David Brownell | 438d6c2 | 2006-12-10 21:21:31 +0100 | [diff] [blame] | 1631 | if (data & 0x8000) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1632 | data = data ^ POLY; |
| 1633 | data = data << 1; |
| 1634 | } |
| 1635 | return (u8)(data >> 8); |
| 1636 | } |
| 1637 | |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 1638 | /* Incremental CRC8 over count bytes in the array pointed to by p */ |
| 1639 | static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1640 | { |
| 1641 | int i; |
| 1642 | |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 1643 | for (i = 0; i < count; i++) |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 1644 | crc = crc8((crc ^ p[i]) << 8); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1645 | return crc; |
| 1646 | } |
| 1647 | |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 1648 | /* Assume a 7-bit address, which is reasonable for SMBus */ |
| 1649 | static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1650 | { |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 1651 | /* The address will be sent first */ |
| 1652 | u8 addr = (msg->addr << 1) | !!(msg->flags & I2C_M_RD); |
| 1653 | pec = i2c_smbus_pec(pec, &addr, 1); |
| 1654 | |
| 1655 | /* The data buffer follows */ |
| 1656 | return i2c_smbus_pec(pec, msg->buf, msg->len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1657 | } |
| 1658 | |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 1659 | /* Used for write only transactions */ |
| 1660 | static inline void i2c_smbus_add_pec(struct i2c_msg *msg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1661 | { |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 1662 | msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg); |
| 1663 | msg->len++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1664 | } |
| 1665 | |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 1666 | /* Return <0 on CRC error |
| 1667 | If there was a write before this read (most cases) we need to take the |
| 1668 | partial CRC from the write part into account. |
| 1669 | Note that this function does modify the message (we need to decrease the |
| 1670 | message length to hide the CRC byte from the caller). */ |
| 1671 | static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1672 | { |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 1673 | u8 rpec = msg->buf[--msg->len]; |
| 1674 | cpec = i2c_smbus_msg_pec(cpec, msg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1675 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1676 | if (rpec != cpec) { |
| 1677 | pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n", |
| 1678 | rpec, cpec); |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 1679 | return -EBADMSG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1680 | } |
David Brownell | 438d6c2 | 2006-12-10 21:21:31 +0100 | [diff] [blame] | 1681 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1682 | } |
| 1683 | |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1684 | /** |
| 1685 | * i2c_smbus_read_byte - SMBus "receive byte" protocol |
| 1686 | * @client: Handle to slave device |
| 1687 | * |
| 1688 | * This executes the SMBus "receive byte" protocol, returning negative errno |
| 1689 | * else the byte received from the device. |
| 1690 | */ |
Jean Delvare | 0cc43a1 | 2011-01-10 22:11:23 +0100 | [diff] [blame] | 1691 | s32 i2c_smbus_read_byte(const struct i2c_client *client) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1692 | { |
| 1693 | union i2c_smbus_data data; |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 1694 | int status; |
| 1695 | |
| 1696 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
| 1697 | I2C_SMBUS_READ, 0, |
| 1698 | I2C_SMBUS_BYTE, &data); |
| 1699 | return (status < 0) ? status : data.byte; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1700 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1701 | EXPORT_SYMBOL(i2c_smbus_read_byte); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1702 | |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1703 | /** |
| 1704 | * i2c_smbus_write_byte - SMBus "send byte" protocol |
| 1705 | * @client: Handle to slave device |
| 1706 | * @value: Byte to be sent |
| 1707 | * |
| 1708 | * This executes the SMBus "send byte" protocol, returning negative errno |
| 1709 | * else zero on success. |
| 1710 | */ |
Jean Delvare | 0cc43a1 | 2011-01-10 22:11:23 +0100 | [diff] [blame] | 1711 | s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1712 | { |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 1713 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 1714 | I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1715 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1716 | EXPORT_SYMBOL(i2c_smbus_write_byte); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1717 | |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1718 | /** |
| 1719 | * i2c_smbus_read_byte_data - SMBus "read byte" protocol |
| 1720 | * @client: Handle to slave device |
| 1721 | * @command: Byte interpreted by slave |
| 1722 | * |
| 1723 | * This executes the SMBus "read byte" protocol, returning negative errno |
| 1724 | * else a data byte received from the device. |
| 1725 | */ |
Jean Delvare | 0cc43a1 | 2011-01-10 22:11:23 +0100 | [diff] [blame] | 1726 | s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1727 | { |
| 1728 | union i2c_smbus_data data; |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 1729 | int status; |
| 1730 | |
| 1731 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
| 1732 | I2C_SMBUS_READ, command, |
| 1733 | I2C_SMBUS_BYTE_DATA, &data); |
| 1734 | return (status < 0) ? status : data.byte; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1735 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1736 | EXPORT_SYMBOL(i2c_smbus_read_byte_data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1737 | |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1738 | /** |
| 1739 | * i2c_smbus_write_byte_data - SMBus "write byte" protocol |
| 1740 | * @client: Handle to slave device |
| 1741 | * @command: Byte interpreted by slave |
| 1742 | * @value: Byte being written |
| 1743 | * |
| 1744 | * This executes the SMBus "write byte" protocol, returning negative errno |
| 1745 | * else zero on success. |
| 1746 | */ |
Jean Delvare | 0cc43a1 | 2011-01-10 22:11:23 +0100 | [diff] [blame] | 1747 | s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command, |
| 1748 | u8 value) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1749 | { |
| 1750 | union i2c_smbus_data data; |
| 1751 | data.byte = value; |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 1752 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
| 1753 | I2C_SMBUS_WRITE, command, |
| 1754 | I2C_SMBUS_BYTE_DATA, &data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1755 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1756 | EXPORT_SYMBOL(i2c_smbus_write_byte_data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1757 | |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1758 | /** |
| 1759 | * i2c_smbus_read_word_data - SMBus "read word" protocol |
| 1760 | * @client: Handle to slave device |
| 1761 | * @command: Byte interpreted by slave |
| 1762 | * |
| 1763 | * This executes the SMBus "read word" protocol, returning negative errno |
| 1764 | * else a 16-bit unsigned "word" received from the device. |
| 1765 | */ |
Jean Delvare | 0cc43a1 | 2011-01-10 22:11:23 +0100 | [diff] [blame] | 1766 | s32 i2c_smbus_read_word_data(const struct i2c_client *client, u8 command) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1767 | { |
| 1768 | union i2c_smbus_data data; |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 1769 | int status; |
| 1770 | |
| 1771 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
| 1772 | I2C_SMBUS_READ, command, |
| 1773 | I2C_SMBUS_WORD_DATA, &data); |
| 1774 | return (status < 0) ? status : data.word; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1775 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1776 | EXPORT_SYMBOL(i2c_smbus_read_word_data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1777 | |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1778 | /** |
| 1779 | * i2c_smbus_write_word_data - SMBus "write word" protocol |
| 1780 | * @client: Handle to slave device |
| 1781 | * @command: Byte interpreted by slave |
| 1782 | * @value: 16-bit "word" being written |
| 1783 | * |
| 1784 | * This executes the SMBus "write word" protocol, returning negative errno |
| 1785 | * else zero on success. |
| 1786 | */ |
Jean Delvare | 0cc43a1 | 2011-01-10 22:11:23 +0100 | [diff] [blame] | 1787 | s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command, |
| 1788 | u16 value) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1789 | { |
| 1790 | union i2c_smbus_data data; |
| 1791 | data.word = value; |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 1792 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
| 1793 | I2C_SMBUS_WRITE, command, |
| 1794 | I2C_SMBUS_WORD_DATA, &data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1795 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1796 | EXPORT_SYMBOL(i2c_smbus_write_word_data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1797 | |
David Brownell | a64ec07 | 2007-10-13 23:56:31 +0200 | [diff] [blame] | 1798 | /** |
Prakash Mortha | 596c88f | 2008-10-14 17:30:06 +0200 | [diff] [blame] | 1799 | * i2c_smbus_process_call - SMBus "process call" protocol |
| 1800 | * @client: Handle to slave device |
| 1801 | * @command: Byte interpreted by slave |
| 1802 | * @value: 16-bit "word" being written |
| 1803 | * |
| 1804 | * This executes the SMBus "process call" protocol, returning negative errno |
| 1805 | * else a 16-bit unsigned "word" received from the device. |
| 1806 | */ |
Jean Delvare | 0cc43a1 | 2011-01-10 22:11:23 +0100 | [diff] [blame] | 1807 | s32 i2c_smbus_process_call(const struct i2c_client *client, u8 command, |
| 1808 | u16 value) |
Prakash Mortha | 596c88f | 2008-10-14 17:30:06 +0200 | [diff] [blame] | 1809 | { |
| 1810 | union i2c_smbus_data data; |
| 1811 | int status; |
| 1812 | data.word = value; |
| 1813 | |
| 1814 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
| 1815 | I2C_SMBUS_WRITE, command, |
| 1816 | I2C_SMBUS_PROC_CALL, &data); |
| 1817 | return (status < 0) ? status : data.word; |
| 1818 | } |
| 1819 | EXPORT_SYMBOL(i2c_smbus_process_call); |
| 1820 | |
| 1821 | /** |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1822 | * i2c_smbus_read_block_data - SMBus "block read" protocol |
David Brownell | a64ec07 | 2007-10-13 23:56:31 +0200 | [diff] [blame] | 1823 | * @client: Handle to slave device |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1824 | * @command: Byte interpreted by slave |
David Brownell | a64ec07 | 2007-10-13 23:56:31 +0200 | [diff] [blame] | 1825 | * @values: Byte array into which data will be read; big enough to hold |
| 1826 | * the data returned by the slave. SMBus allows at most 32 bytes. |
| 1827 | * |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1828 | * This executes the SMBus "block read" protocol, returning negative errno |
| 1829 | * else the number of data bytes in the slave's response. |
David Brownell | a64ec07 | 2007-10-13 23:56:31 +0200 | [diff] [blame] | 1830 | * |
| 1831 | * Note that using this function requires that the client's adapter support |
| 1832 | * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality. Not all adapter drivers |
| 1833 | * support this; its emulation through I2C messaging relies on a specific |
| 1834 | * mechanism (I2C_M_RECV_LEN) which may not be implemented. |
| 1835 | */ |
Jean Delvare | 0cc43a1 | 2011-01-10 22:11:23 +0100 | [diff] [blame] | 1836 | s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command, |
Jean Delvare | b86a1bc | 2007-05-01 23:26:34 +0200 | [diff] [blame] | 1837 | u8 *values) |
| 1838 | { |
| 1839 | union i2c_smbus_data data; |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 1840 | int status; |
Jean Delvare | b86a1bc | 2007-05-01 23:26:34 +0200 | [diff] [blame] | 1841 | |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 1842 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
| 1843 | I2C_SMBUS_READ, command, |
| 1844 | I2C_SMBUS_BLOCK_DATA, &data); |
| 1845 | if (status) |
| 1846 | return status; |
Jean Delvare | b86a1bc | 2007-05-01 23:26:34 +0200 | [diff] [blame] | 1847 | |
| 1848 | memcpy(values, &data.block[1], data.block[0]); |
| 1849 | return data.block[0]; |
| 1850 | } |
| 1851 | EXPORT_SYMBOL(i2c_smbus_read_block_data); |
| 1852 | |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 1853 | /** |
| 1854 | * i2c_smbus_write_block_data - SMBus "block write" protocol |
| 1855 | * @client: Handle to slave device |
| 1856 | * @command: Byte interpreted by slave |
| 1857 | * @length: Size of data block; SMBus allows at most 32 bytes |
| 1858 | * @values: Byte array which will be written. |
| 1859 | * |
| 1860 | * This executes the SMBus "block write" protocol, returning negative errno |
| 1861 | * else zero on success. |
| 1862 | */ |
Jean Delvare | 0cc43a1 | 2011-01-10 22:11:23 +0100 | [diff] [blame] | 1863 | s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command, |
Krzysztof Halasa | 46f5ed7 | 2006-06-12 21:42:20 +0200 | [diff] [blame] | 1864 | u8 length, const u8 *values) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1865 | { |
| 1866 | union i2c_smbus_data data; |
Jean Delvare | 7656032 | 2006-01-18 23:14:55 +0100 | [diff] [blame] | 1867 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1868 | if (length > I2C_SMBUS_BLOCK_MAX) |
| 1869 | length = I2C_SMBUS_BLOCK_MAX; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1870 | data.block[0] = length; |
Jean Delvare | 7656032 | 2006-01-18 23:14:55 +0100 | [diff] [blame] | 1871 | memcpy(&data.block[1], values, length); |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 1872 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
| 1873 | I2C_SMBUS_WRITE, command, |
| 1874 | I2C_SMBUS_BLOCK_DATA, &data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1875 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1876 | EXPORT_SYMBOL(i2c_smbus_write_block_data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1877 | |
| 1878 | /* Returns the number of read bytes */ |
Jean Delvare | 0cc43a1 | 2011-01-10 22:11:23 +0100 | [diff] [blame] | 1879 | s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command, |
Jean Delvare | 4b2643d | 2007-07-12 14:12:29 +0200 | [diff] [blame] | 1880 | u8 length, u8 *values) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1881 | { |
| 1882 | union i2c_smbus_data data; |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 1883 | int status; |
Jean Delvare | 7656032 | 2006-01-18 23:14:55 +0100 | [diff] [blame] | 1884 | |
Jean Delvare | 4b2643d | 2007-07-12 14:12:29 +0200 | [diff] [blame] | 1885 | if (length > I2C_SMBUS_BLOCK_MAX) |
| 1886 | length = I2C_SMBUS_BLOCK_MAX; |
| 1887 | data.block[0] = length; |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 1888 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
| 1889 | I2C_SMBUS_READ, command, |
| 1890 | I2C_SMBUS_I2C_BLOCK_DATA, &data); |
| 1891 | if (status < 0) |
| 1892 | return status; |
Jean Delvare | 7656032 | 2006-01-18 23:14:55 +0100 | [diff] [blame] | 1893 | |
| 1894 | memcpy(values, &data.block[1], data.block[0]); |
| 1895 | return data.block[0]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1896 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1897 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1898 | |
Jean Delvare | 0cc43a1 | 2011-01-10 22:11:23 +0100 | [diff] [blame] | 1899 | s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command, |
Krzysztof Halasa | 46f5ed7 | 2006-06-12 21:42:20 +0200 | [diff] [blame] | 1900 | u8 length, const u8 *values) |
Jean Delvare | 21bbd69 | 2006-01-09 15:19:18 +1100 | [diff] [blame] | 1901 | { |
| 1902 | union i2c_smbus_data data; |
| 1903 | |
| 1904 | if (length > I2C_SMBUS_BLOCK_MAX) |
| 1905 | length = I2C_SMBUS_BLOCK_MAX; |
| 1906 | data.block[0] = length; |
| 1907 | memcpy(data.block + 1, values, length); |
| 1908 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
| 1909 | I2C_SMBUS_WRITE, command, |
| 1910 | I2C_SMBUS_I2C_BLOCK_DATA, &data); |
| 1911 | } |
David Brownell | c056460 | 2007-05-01 23:26:31 +0200 | [diff] [blame] | 1912 | EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data); |
Jean Delvare | 21bbd69 | 2006-01-09 15:19:18 +1100 | [diff] [blame] | 1913 | |
David Brownell | 438d6c2 | 2006-12-10 21:21:31 +0100 | [diff] [blame] | 1914 | /* Simulate a SMBus command using the i2c protocol |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1915 | No checking of parameters is done! */ |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 1916 | static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, |
| 1917 | unsigned short flags, |
| 1918 | char read_write, u8 command, int size, |
| 1919 | union i2c_smbus_data *data) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1920 | { |
| 1921 | /* So we need to generate a series of msgs. In the case of writing, we |
| 1922 | need to use only one message; when reading, we need two. We initialize |
| 1923 | most things with sane defaults, to keep the code below somewhat |
| 1924 | simpler. */ |
Hideki Iwamoto | 5c50d18 | 2005-09-25 17:01:11 +0200 | [diff] [blame] | 1925 | unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; |
| 1926 | unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 1927 | int num = read_write == I2C_SMBUS_READ ? 2 : 1; |
David Brownell | 438d6c2 | 2006-12-10 21:21:31 +0100 | [diff] [blame] | 1928 | struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 }, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1929 | { addr, flags | I2C_M_RD, 0, msgbuf1 } |
| 1930 | }; |
| 1931 | int i; |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 1932 | u8 partial_pec = 0; |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 1933 | int status; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1934 | |
| 1935 | msgbuf0[0] = command; |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 1936 | switch (size) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1937 | case I2C_SMBUS_QUICK: |
| 1938 | msg[0].len = 0; |
| 1939 | /* Special case: The read/write field is used as data */ |
Roel Kluin | f29d2e0 | 2009-02-24 19:19:48 +0100 | [diff] [blame] | 1940 | msg[0].flags = flags | (read_write == I2C_SMBUS_READ ? |
| 1941 | I2C_M_RD : 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1942 | num = 1; |
| 1943 | break; |
| 1944 | case I2C_SMBUS_BYTE: |
| 1945 | if (read_write == I2C_SMBUS_READ) { |
| 1946 | /* Special case: only a read! */ |
| 1947 | msg[0].flags = I2C_M_RD | flags; |
| 1948 | num = 1; |
| 1949 | } |
| 1950 | break; |
| 1951 | case I2C_SMBUS_BYTE_DATA: |
| 1952 | if (read_write == I2C_SMBUS_READ) |
| 1953 | msg[1].len = 1; |
| 1954 | else { |
| 1955 | msg[0].len = 2; |
| 1956 | msgbuf0[1] = data->byte; |
| 1957 | } |
| 1958 | break; |
| 1959 | case I2C_SMBUS_WORD_DATA: |
| 1960 | if (read_write == I2C_SMBUS_READ) |
| 1961 | msg[1].len = 2; |
| 1962 | else { |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 1963 | msg[0].len = 3; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1964 | msgbuf0[1] = data->word & 0xff; |
Jean Delvare | 7eff82c | 2006-09-03 22:24:00 +0200 | [diff] [blame] | 1965 | msgbuf0[2] = data->word >> 8; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1966 | } |
| 1967 | break; |
| 1968 | case I2C_SMBUS_PROC_CALL: |
| 1969 | num = 2; /* Special case */ |
| 1970 | read_write = I2C_SMBUS_READ; |
| 1971 | msg[0].len = 3; |
| 1972 | msg[1].len = 2; |
| 1973 | msgbuf0[1] = data->word & 0xff; |
Jean Delvare | 7eff82c | 2006-09-03 22:24:00 +0200 | [diff] [blame] | 1974 | msgbuf0[2] = data->word >> 8; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1975 | break; |
| 1976 | case I2C_SMBUS_BLOCK_DATA: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1977 | if (read_write == I2C_SMBUS_READ) { |
Jean Delvare | 209d27c | 2007-05-01 23:26:29 +0200 | [diff] [blame] | 1978 | msg[1].flags |= I2C_M_RECV_LEN; |
| 1979 | msg[1].len = 1; /* block length will be added by |
| 1980 | the underlying bus driver */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1981 | } else { |
| 1982 | msg[0].len = data->block[0] + 2; |
| 1983 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) { |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 1984 | dev_err(&adapter->dev, |
| 1985 | "Invalid block write size %d\n", |
| 1986 | data->block[0]); |
| 1987 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1988 | } |
Hideki Iwamoto | 5c50d18 | 2005-09-25 17:01:11 +0200 | [diff] [blame] | 1989 | for (i = 1; i < msg[0].len; i++) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1990 | msgbuf0[i] = data->block[i-1]; |
| 1991 | } |
| 1992 | break; |
| 1993 | case I2C_SMBUS_BLOCK_PROC_CALL: |
Jean Delvare | 209d27c | 2007-05-01 23:26:29 +0200 | [diff] [blame] | 1994 | num = 2; /* Another special case */ |
| 1995 | read_write = I2C_SMBUS_READ; |
| 1996 | if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 1997 | dev_err(&adapter->dev, |
| 1998 | "Invalid block write size %d\n", |
Jean Delvare | 209d27c | 2007-05-01 23:26:29 +0200 | [diff] [blame] | 1999 | data->block[0]); |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 2000 | return -EINVAL; |
Jean Delvare | 209d27c | 2007-05-01 23:26:29 +0200 | [diff] [blame] | 2001 | } |
| 2002 | msg[0].len = data->block[0] + 2; |
| 2003 | for (i = 1; i < msg[0].len; i++) |
| 2004 | msgbuf0[i] = data->block[i-1]; |
| 2005 | msg[1].flags |= I2C_M_RECV_LEN; |
| 2006 | msg[1].len = 1; /* block length will be added by |
| 2007 | the underlying bus driver */ |
| 2008 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2009 | case I2C_SMBUS_I2C_BLOCK_DATA: |
| 2010 | if (read_write == I2C_SMBUS_READ) { |
Jean Delvare | 4b2643d | 2007-07-12 14:12:29 +0200 | [diff] [blame] | 2011 | msg[1].len = data->block[0]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2012 | } else { |
| 2013 | msg[0].len = data->block[0] + 1; |
Jean Delvare | 30dac74 | 2005-10-08 00:15:59 +0200 | [diff] [blame] | 2014 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) { |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 2015 | dev_err(&adapter->dev, |
| 2016 | "Invalid block write size %d\n", |
| 2017 | data->block[0]); |
| 2018 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2019 | } |
| 2020 | for (i = 1; i <= data->block[0]; i++) |
| 2021 | msgbuf0[i] = data->block[i]; |
| 2022 | } |
| 2023 | break; |
| 2024 | default: |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 2025 | dev_err(&adapter->dev, "Unsupported transaction %d\n", size); |
| 2026 | return -EOPNOTSUPP; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2027 | } |
| 2028 | |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 2029 | i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK |
| 2030 | && size != I2C_SMBUS_I2C_BLOCK_DATA); |
| 2031 | if (i) { |
| 2032 | /* Compute PEC if first message is a write */ |
| 2033 | if (!(msg[0].flags & I2C_M_RD)) { |
David Brownell | 438d6c2 | 2006-12-10 21:21:31 +0100 | [diff] [blame] | 2034 | if (num == 1) /* Write only */ |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 2035 | i2c_smbus_add_pec(&msg[0]); |
| 2036 | else /* Write followed by read */ |
| 2037 | partial_pec = i2c_smbus_msg_pec(0, &msg[0]); |
| 2038 | } |
| 2039 | /* Ask for PEC if last message is a read */ |
| 2040 | if (msg[num-1].flags & I2C_M_RD) |
David Brownell | 438d6c2 | 2006-12-10 21:21:31 +0100 | [diff] [blame] | 2041 | msg[num-1].len++; |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 2042 | } |
| 2043 | |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 2044 | status = i2c_transfer(adapter, msg, num); |
| 2045 | if (status < 0) |
| 2046 | return status; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2047 | |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 2048 | /* Check PEC if last message is a read */ |
| 2049 | if (i && (msg[num-1].flags & I2C_M_RD)) { |
David Brownell | 24a5bb7 | 2008-07-14 22:38:23 +0200 | [diff] [blame] | 2050 | status = i2c_smbus_check_pec(partial_pec, &msg[num-1]); |
| 2051 | if (status < 0) |
| 2052 | return status; |
Jean Delvare | 421ef47 | 2005-10-26 21:28:55 +0200 | [diff] [blame] | 2053 | } |
| 2054 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2055 | if (read_write == I2C_SMBUS_READ) |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 2056 | switch (size) { |
| 2057 | case I2C_SMBUS_BYTE: |
| 2058 | data->byte = msgbuf0[0]; |
| 2059 | break; |
| 2060 | case I2C_SMBUS_BYTE_DATA: |
| 2061 | data->byte = msgbuf1[0]; |
| 2062 | break; |
| 2063 | case I2C_SMBUS_WORD_DATA: |
| 2064 | case I2C_SMBUS_PROC_CALL: |
| 2065 | data->word = msgbuf1[0] | (msgbuf1[1] << 8); |
| 2066 | break; |
| 2067 | case I2C_SMBUS_I2C_BLOCK_DATA: |
| 2068 | for (i = 0; i < data->block[0]; i++) |
| 2069 | data->block[i+1] = msgbuf1[i]; |
| 2070 | break; |
| 2071 | case I2C_SMBUS_BLOCK_DATA: |
| 2072 | case I2C_SMBUS_BLOCK_PROC_CALL: |
| 2073 | for (i = 0; i < msgbuf1[0] + 1; i++) |
| 2074 | data->block[i] = msgbuf1[i]; |
| 2075 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2076 | } |
| 2077 | return 0; |
| 2078 | } |
| 2079 | |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 2080 | /** |
| 2081 | * i2c_smbus_xfer - execute SMBus protocol operations |
| 2082 | * @adapter: Handle to I2C bus |
| 2083 | * @addr: Address of SMBus slave on that bus |
| 2084 | * @flags: I2C_CLIENT_* flags (usually zero or I2C_CLIENT_PEC) |
| 2085 | * @read_write: I2C_SMBUS_READ or I2C_SMBUS_WRITE |
| 2086 | * @command: Byte interpreted by slave, for protocols which use such bytes |
| 2087 | * @protocol: SMBus protocol operation to execute, such as I2C_SMBUS_PROC_CALL |
| 2088 | * @data: Data to be read or written |
| 2089 | * |
| 2090 | * This executes an SMBus protocol operation, and returns a negative |
| 2091 | * errno code else zero on success. |
| 2092 | */ |
Zhenwen Xu | 09b8ce0 | 2009-03-28 21:34:46 +0100 | [diff] [blame] | 2093 | s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 2094 | char read_write, u8 command, int protocol, |
Zhenwen Xu | 09b8ce0 | 2009-03-28 21:34:46 +0100 | [diff] [blame] | 2095 | union i2c_smbus_data *data) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2096 | { |
Clifford Wolf | 66b650f | 2009-06-15 18:01:46 +0200 | [diff] [blame] | 2097 | unsigned long orig_jiffies; |
| 2098 | int try; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2099 | s32 res; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2100 | |
| 2101 | flags &= I2C_M_TEN | I2C_CLIENT_PEC; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2102 | |
| 2103 | if (adapter->algo->smbus_xfer) { |
Jean Delvare | fe61e07 | 2010-08-11 18:20:58 +0200 | [diff] [blame] | 2104 | i2c_lock_adapter(adapter); |
Clifford Wolf | 66b650f | 2009-06-15 18:01:46 +0200 | [diff] [blame] | 2105 | |
| 2106 | /* Retry automatically on arbitration loss */ |
| 2107 | orig_jiffies = jiffies; |
| 2108 | for (res = 0, try = 0; try <= adapter->retries; try++) { |
| 2109 | res = adapter->algo->smbus_xfer(adapter, addr, flags, |
| 2110 | read_write, command, |
| 2111 | protocol, data); |
| 2112 | if (res != -EAGAIN) |
| 2113 | break; |
| 2114 | if (time_after(jiffies, |
| 2115 | orig_jiffies + adapter->timeout)) |
| 2116 | break; |
| 2117 | } |
Jean Delvare | fe61e07 | 2010-08-11 18:20:58 +0200 | [diff] [blame] | 2118 | i2c_unlock_adapter(adapter); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2119 | } else |
Farid Hammane | 7225acf | 2010-05-21 18:40:58 +0200 | [diff] [blame] | 2120 | res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write, |
David Brownell | a1cdeda | 2008-07-14 22:38:24 +0200 | [diff] [blame] | 2121 | command, protocol, data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2122 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2123 | return res; |
| 2124 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2125 | EXPORT_SYMBOL(i2c_smbus_xfer); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2126 | |
| 2127 | MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); |
| 2128 | MODULE_DESCRIPTION("I2C-Bus main module"); |
| 2129 | MODULE_LICENSE("GPL"); |