Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Apple Motion Sensor driver (I2C variant) |
| 3 | * |
| 4 | * Copyright (C) 2005 Stelian Pop (stelian@popies.net) |
| 5 | * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch) |
| 6 | * |
| 7 | * Clean room implementation based on the reverse engineered Mac OS X driver by |
| 8 | * Johannes Berg <johannes@sipsolutions.net>, documentation available at |
| 9 | * http://johannes.sipsolutions.net/PowerBook/Apple_Motion_Sensor_Specification |
| 10 | * |
| 11 | * This program is free software; you can redistribute it and/or modify |
| 12 | * it under the terms of the GNU General Public License as published by |
| 13 | * the Free Software Foundation; either version 2 of the License, or |
| 14 | * (at your option) any later version. |
| 15 | */ |
| 16 | |
| 17 | #include <linux/module.h> |
| 18 | #include <linux/types.h> |
| 19 | #include <linux/errno.h> |
| 20 | #include <linux/init.h> |
| 21 | #include <linux/delay.h> |
| 22 | |
| 23 | #include "ams.h" |
| 24 | |
| 25 | /* AMS registers */ |
| 26 | #define AMS_COMMAND 0x00 /* command register */ |
| 27 | #define AMS_STATUS 0x01 /* status register */ |
| 28 | #define AMS_CTRL1 0x02 /* read control 1 (number of values) */ |
| 29 | #define AMS_CTRL2 0x03 /* read control 2 (offset?) */ |
| 30 | #define AMS_CTRL3 0x04 /* read control 3 (size of each value?) */ |
| 31 | #define AMS_DATA1 0x05 /* read data 1 */ |
| 32 | #define AMS_DATA2 0x06 /* read data 2 */ |
| 33 | #define AMS_DATA3 0x07 /* read data 3 */ |
| 34 | #define AMS_DATA4 0x08 /* read data 4 */ |
| 35 | #define AMS_DATAX 0x20 /* data X */ |
| 36 | #define AMS_DATAY 0x21 /* data Y */ |
| 37 | #define AMS_DATAZ 0x22 /* data Z */ |
| 38 | #define AMS_FREEFALL 0x24 /* freefall int control */ |
| 39 | #define AMS_SHOCK 0x25 /* shock int control */ |
| 40 | #define AMS_SENSLOW 0x26 /* sensitivity low limit */ |
| 41 | #define AMS_SENSHIGH 0x27 /* sensitivity high limit */ |
| 42 | #define AMS_CTRLX 0x28 /* control X */ |
| 43 | #define AMS_CTRLY 0x29 /* control Y */ |
| 44 | #define AMS_CTRLZ 0x2A /* control Z */ |
| 45 | #define AMS_UNKNOWN1 0x2B /* unknown 1 */ |
| 46 | #define AMS_UNKNOWN2 0x2C /* unknown 2 */ |
| 47 | #define AMS_UNKNOWN3 0x2D /* unknown 3 */ |
| 48 | #define AMS_VENDOR 0x2E /* vendor */ |
| 49 | |
| 50 | /* AMS commands - use with the AMS_COMMAND register */ |
| 51 | enum ams_i2c_cmd { |
| 52 | AMS_CMD_NOOP = 0, |
| 53 | AMS_CMD_VERSION, |
| 54 | AMS_CMD_READMEM, |
| 55 | AMS_CMD_WRITEMEM, |
| 56 | AMS_CMD_ERASEMEM, |
| 57 | AMS_CMD_READEE, |
| 58 | AMS_CMD_WRITEEE, |
| 59 | AMS_CMD_RESET, |
| 60 | AMS_CMD_START, |
| 61 | }; |
| 62 | |
Jean Delvare | 810ad7b | 2008-10-17 17:51:12 +0200 | [diff] [blame] | 63 | static int ams_i2c_probe(struct i2c_client *client, |
| 64 | const struct i2c_device_id *id); |
| 65 | static int ams_i2c_remove(struct i2c_client *client); |
| 66 | |
| 67 | static const struct i2c_device_id ams_id[] = { |
| 68 | { "ams", 0 }, |
| 69 | { } |
| 70 | }; |
| 71 | MODULE_DEVICE_TABLE(i2c, ams_id); |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 72 | |
| 73 | static struct i2c_driver ams_i2c_driver = { |
| 74 | .driver = { |
| 75 | .name = "ams", |
| 76 | .owner = THIS_MODULE, |
| 77 | }, |
Jean Delvare | 810ad7b | 2008-10-17 17:51:12 +0200 | [diff] [blame] | 78 | .probe = ams_i2c_probe, |
| 79 | .remove = ams_i2c_remove, |
| 80 | .id_table = ams_id, |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 81 | }; |
| 82 | |
| 83 | static s32 ams_i2c_read(u8 reg) |
| 84 | { |
Jean Delvare | 810ad7b | 2008-10-17 17:51:12 +0200 | [diff] [blame] | 85 | return i2c_smbus_read_byte_data(ams_info.i2c_client, reg); |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 86 | } |
| 87 | |
| 88 | static int ams_i2c_write(u8 reg, u8 value) |
| 89 | { |
Jean Delvare | 810ad7b | 2008-10-17 17:51:12 +0200 | [diff] [blame] | 90 | return i2c_smbus_write_byte_data(ams_info.i2c_client, reg, value); |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 91 | } |
| 92 | |
| 93 | static int ams_i2c_cmd(enum ams_i2c_cmd cmd) |
| 94 | { |
| 95 | s32 result; |
Stelian Pop | 63232dc | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 96 | int count = 3; |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 97 | |
| 98 | ams_i2c_write(AMS_COMMAND, cmd); |
Stelian Pop | 63232dc | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 99 | msleep(5); |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 100 | |
Stelian Pop | 63232dc | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 101 | while (count--) { |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 102 | result = ams_i2c_read(AMS_COMMAND); |
| 103 | if (result == 0 || result & 0x80) |
| 104 | return 0; |
| 105 | |
Stelian Pop | 63232dc | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 106 | schedule_timeout_uninterruptible(HZ / 20); |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 107 | } |
| 108 | |
| 109 | return -1; |
| 110 | } |
| 111 | |
| 112 | static void ams_i2c_set_irq(enum ams_irq reg, char enable) |
| 113 | { |
| 114 | if (reg & AMS_IRQ_FREEFALL) { |
| 115 | u8 val = ams_i2c_read(AMS_CTRLX); |
| 116 | if (enable) |
| 117 | val |= 0x80; |
| 118 | else |
| 119 | val &= ~0x80; |
| 120 | ams_i2c_write(AMS_CTRLX, val); |
| 121 | } |
| 122 | |
| 123 | if (reg & AMS_IRQ_SHOCK) { |
| 124 | u8 val = ams_i2c_read(AMS_CTRLY); |
| 125 | if (enable) |
| 126 | val |= 0x80; |
| 127 | else |
| 128 | val &= ~0x80; |
| 129 | ams_i2c_write(AMS_CTRLY, val); |
| 130 | } |
| 131 | |
| 132 | if (reg & AMS_IRQ_GLOBAL) { |
| 133 | u8 val = ams_i2c_read(AMS_CTRLZ); |
| 134 | if (enable) |
| 135 | val |= 0x80; |
| 136 | else |
| 137 | val &= ~0x80; |
| 138 | ams_i2c_write(AMS_CTRLZ, val); |
| 139 | } |
| 140 | } |
| 141 | |
| 142 | static void ams_i2c_clear_irq(enum ams_irq reg) |
| 143 | { |
| 144 | if (reg & AMS_IRQ_FREEFALL) |
| 145 | ams_i2c_write(AMS_FREEFALL, 0); |
| 146 | |
| 147 | if (reg & AMS_IRQ_SHOCK) |
| 148 | ams_i2c_write(AMS_SHOCK, 0); |
| 149 | } |
| 150 | |
| 151 | static u8 ams_i2c_get_vendor(void) |
| 152 | { |
| 153 | return ams_i2c_read(AMS_VENDOR); |
| 154 | } |
| 155 | |
| 156 | static void ams_i2c_get_xyz(s8 *x, s8 *y, s8 *z) |
| 157 | { |
| 158 | *x = ams_i2c_read(AMS_DATAX); |
| 159 | *y = ams_i2c_read(AMS_DATAY); |
| 160 | *z = ams_i2c_read(AMS_DATAZ); |
| 161 | } |
| 162 | |
Jean Delvare | 810ad7b | 2008-10-17 17:51:12 +0200 | [diff] [blame] | 163 | static int ams_i2c_probe(struct i2c_client *client, |
| 164 | const struct i2c_device_id *id) |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 165 | { |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 166 | int vmaj, vmin; |
| 167 | int result; |
| 168 | |
| 169 | /* There can be only one */ |
| 170 | if (unlikely(ams_info.has_device)) |
| 171 | return -ENODEV; |
| 172 | |
Jean Delvare | 810ad7b | 2008-10-17 17:51:12 +0200 | [diff] [blame] | 173 | ams_info.i2c_client = client; |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 174 | |
| 175 | if (ams_i2c_cmd(AMS_CMD_RESET)) { |
| 176 | printk(KERN_INFO "ams: Failed to reset the device\n"); |
| 177 | return -ENODEV; |
| 178 | } |
| 179 | |
| 180 | if (ams_i2c_cmd(AMS_CMD_START)) { |
| 181 | printk(KERN_INFO "ams: Failed to start the device\n"); |
| 182 | return -ENODEV; |
| 183 | } |
| 184 | |
| 185 | /* get version/vendor information */ |
| 186 | ams_i2c_write(AMS_CTRL1, 0x02); |
| 187 | ams_i2c_write(AMS_CTRL2, 0x85); |
| 188 | ams_i2c_write(AMS_CTRL3, 0x01); |
| 189 | |
| 190 | ams_i2c_cmd(AMS_CMD_READMEM); |
| 191 | |
| 192 | vmaj = ams_i2c_read(AMS_DATA1); |
| 193 | vmin = ams_i2c_read(AMS_DATA2); |
| 194 | if (vmaj != 1 || vmin != 52) { |
| 195 | printk(KERN_INFO "ams: Incorrect device version (%d.%d)\n", |
| 196 | vmaj, vmin); |
| 197 | return -ENODEV; |
| 198 | } |
| 199 | |
| 200 | ams_i2c_cmd(AMS_CMD_VERSION); |
| 201 | |
| 202 | vmaj = ams_i2c_read(AMS_DATA1); |
| 203 | vmin = ams_i2c_read(AMS_DATA2); |
| 204 | if (vmaj != 0 || vmin != 1) { |
| 205 | printk(KERN_INFO "ams: Incorrect firmware version (%d.%d)\n", |
| 206 | vmaj, vmin); |
| 207 | return -ENODEV; |
| 208 | } |
| 209 | |
| 210 | /* Disable interrupts */ |
| 211 | ams_i2c_set_irq(AMS_IRQ_ALL, 0); |
| 212 | |
| 213 | result = ams_sensor_attach(); |
| 214 | if (result < 0) |
| 215 | return result; |
| 216 | |
| 217 | /* Set default values */ |
| 218 | ams_i2c_write(AMS_SENSLOW, 0x15); |
| 219 | ams_i2c_write(AMS_SENSHIGH, 0x60); |
| 220 | ams_i2c_write(AMS_CTRLX, 0x08); |
| 221 | ams_i2c_write(AMS_CTRLY, 0x0F); |
| 222 | ams_i2c_write(AMS_CTRLZ, 0x4F); |
| 223 | ams_i2c_write(AMS_UNKNOWN1, 0x14); |
| 224 | |
| 225 | /* Clear interrupts */ |
| 226 | ams_i2c_clear_irq(AMS_IRQ_ALL); |
| 227 | |
| 228 | ams_info.has_device = 1; |
| 229 | |
| 230 | /* Enable interrupts */ |
| 231 | ams_i2c_set_irq(AMS_IRQ_ALL, 1); |
| 232 | |
| 233 | printk(KERN_INFO "ams: Found I2C based motion sensor\n"); |
| 234 | |
| 235 | return 0; |
| 236 | } |
| 237 | |
Jean Delvare | 810ad7b | 2008-10-17 17:51:12 +0200 | [diff] [blame] | 238 | static int ams_i2c_remove(struct i2c_client *client) |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 239 | { |
| 240 | if (ams_info.has_device) { |
| 241 | /* Disable interrupts */ |
| 242 | ams_i2c_set_irq(AMS_IRQ_ALL, 0); |
| 243 | |
| 244 | /* Clear interrupts */ |
| 245 | ams_i2c_clear_irq(AMS_IRQ_ALL); |
| 246 | |
| 247 | printk(KERN_INFO "ams: Unloading\n"); |
| 248 | |
| 249 | ams_info.has_device = 0; |
| 250 | } |
| 251 | |
| 252 | return 0; |
| 253 | } |
| 254 | |
| 255 | static void ams_i2c_exit(void) |
| 256 | { |
| 257 | i2c_del_driver(&ams_i2c_driver); |
| 258 | } |
| 259 | |
| 260 | int __init ams_i2c_init(struct device_node *np) |
| 261 | { |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 262 | int result; |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 263 | |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 264 | /* Set implementation stuff */ |
| 265 | ams_info.of_node = np; |
| 266 | ams_info.exit = ams_i2c_exit; |
| 267 | ams_info.get_vendor = ams_i2c_get_vendor; |
| 268 | ams_info.get_xyz = ams_i2c_get_xyz; |
| 269 | ams_info.clear_irq = ams_i2c_clear_irq; |
| 270 | ams_info.bustype = BUS_I2C; |
| 271 | |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 272 | result = i2c_add_driver(&ams_i2c_driver); |
| 273 | |
Stelian Pop | dcb69dd | 2006-12-12 18:18:30 +0100 | [diff] [blame] | 274 | return result; |
| 275 | } |