| /* |
| i2c Support for Apple SMU Controller |
| |
| Copyright (c) 2005 Benjamin Herrenschmidt, IBM Corp. |
| <benh@kernel.crashing.org> |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; if not, write to the Free Software |
| Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/types.h> |
| #include <linux/i2c.h> |
| #include <linux/init.h> |
| #include <linux/device.h> |
| #include <linux/platform_device.h> |
| #include <asm/prom.h> |
| #include <asm/pmac_low_i2c.h> |
| |
| MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); |
| MODULE_DESCRIPTION("I2C driver for Apple PowerMac"); |
| MODULE_LICENSE("GPL"); |
| |
| /* |
| * SMBUS-type transfer entrypoint |
| */ |
| static s32 i2c_powermac_smbus_xfer( struct i2c_adapter* adap, |
| u16 addr, |
| unsigned short flags, |
| char read_write, |
| u8 command, |
| int size, |
| union i2c_smbus_data* data) |
| { |
| struct pmac_i2c_bus *bus = i2c_get_adapdata(adap); |
| int rc = 0; |
| int read = (read_write == I2C_SMBUS_READ); |
| int addrdir = (addr << 1) | read; |
| u8 local[2]; |
| |
| rc = pmac_i2c_open(bus, 0); |
| if (rc) |
| return rc; |
| |
| switch (size) { |
| case I2C_SMBUS_QUICK: |
| rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std); |
| if (rc) |
| goto bail; |
| rc = pmac_i2c_xfer(bus, addrdir, 0, 0, NULL, 0); |
| break; |
| case I2C_SMBUS_BYTE: |
| rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std); |
| if (rc) |
| goto bail; |
| rc = pmac_i2c_xfer(bus, addrdir, 0, 0, &data->byte, 1); |
| break; |
| case I2C_SMBUS_BYTE_DATA: |
| rc = pmac_i2c_setmode(bus, read ? |
| pmac_i2c_mode_combined : |
| pmac_i2c_mode_stdsub); |
| if (rc) |
| goto bail; |
| rc = pmac_i2c_xfer(bus, addrdir, 1, command, &data->byte, 1); |
| break; |
| case I2C_SMBUS_WORD_DATA: |
| rc = pmac_i2c_setmode(bus, read ? |
| pmac_i2c_mode_combined : |
| pmac_i2c_mode_stdsub); |
| if (rc) |
| goto bail; |
| if (!read) { |
| local[0] = data->word & 0xff; |
| local[1] = (data->word >> 8) & 0xff; |
| } |
| rc = pmac_i2c_xfer(bus, addrdir, 1, command, local, 2); |
| if (rc == 0 && read) { |
| data->word = ((u16)local[1]) << 8; |
| data->word |= local[0]; |
| } |
| break; |
| |
| /* Note that these are broken vs. the expected smbus API where |
| * on reads, the length is actually returned from the function, |
| * but I think the current API makes no sense and I don't want |
| * any driver that I haven't verified for correctness to go |
| * anywhere near a pmac i2c bus anyway ... |
| * |
| * I'm also not completely sure what kind of phases to do between |
| * the actual command and the data (what I am _supposed_ to do that |
| * is). For now, I assume writes are a single stream and reads have |
| * a repeat start/addr phase (but not stop in between) |
| */ |
| case I2C_SMBUS_BLOCK_DATA: |
| rc = pmac_i2c_setmode(bus, read ? |
| pmac_i2c_mode_combined : |
| pmac_i2c_mode_stdsub); |
| if (rc) |
| goto bail; |
| rc = pmac_i2c_xfer(bus, addrdir, 1, command, data->block, |
| data->block[0] + 1); |
| |
| break; |
| case I2C_SMBUS_I2C_BLOCK_DATA: |
| rc = pmac_i2c_setmode(bus, read ? |
| pmac_i2c_mode_combined : |
| pmac_i2c_mode_stdsub); |
| if (rc) |
| goto bail; |
| rc = pmac_i2c_xfer(bus, addrdir, 1, command, |
| &data->block[1], data->block[0]); |
| break; |
| |
| default: |
| rc = -EINVAL; |
| } |
| bail: |
| pmac_i2c_close(bus); |
| return rc; |
| } |
| |
| /* |
| * Generic i2c master transfer entrypoint. This driver only support single |
| * messages (for "lame i2c" transfers). Anything else should use the smbus |
| * entry point |
| */ |
| static int i2c_powermac_master_xfer( struct i2c_adapter *adap, |
| struct i2c_msg *msgs, |
| int num) |
| { |
| struct pmac_i2c_bus *bus = i2c_get_adapdata(adap); |
| int rc = 0; |
| int read; |
| int addrdir; |
| |
| if (msgs->flags & I2C_M_TEN) |
| return -EINVAL; |
| read = (msgs->flags & I2C_M_RD) != 0; |
| addrdir = (msgs->addr << 1) | read; |
| if (msgs->flags & I2C_M_REV_DIR_ADDR) |
| addrdir ^= 1; |
| |
| rc = pmac_i2c_open(bus, 0); |
| if (rc) |
| return rc; |
| rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std); |
| if (rc) |
| goto bail; |
| rc = pmac_i2c_xfer(bus, addrdir, 0, 0, msgs->buf, msgs->len); |
| bail: |
| pmac_i2c_close(bus); |
| return rc < 0 ? rc : 1; |
| } |
| |
| static u32 i2c_powermac_func(struct i2c_adapter * adapter) |
| { |
| return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | |
| I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | |
| I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_I2C; |
| } |
| |
| /* For now, we only handle smbus */ |
| static const struct i2c_algorithm i2c_powermac_algorithm = { |
| .smbus_xfer = i2c_powermac_smbus_xfer, |
| .master_xfer = i2c_powermac_master_xfer, |
| .functionality = i2c_powermac_func, |
| }; |
| |
| |
| static int __devexit i2c_powermac_remove(struct platform_device *dev) |
| { |
| struct i2c_adapter *adapter = platform_get_drvdata(dev); |
| struct pmac_i2c_bus *bus = i2c_get_adapdata(adapter); |
| int rc; |
| |
| rc = i2c_del_adapter(adapter); |
| pmac_i2c_detach_adapter(bus, adapter); |
| i2c_set_adapdata(adapter, NULL); |
| /* We aren't that prepared to deal with this... */ |
| if (rc) |
| printk(KERN_WARNING |
| "i2c-powermac.c: Failed to remove bus %s !\n", |
| adapter->name); |
| platform_set_drvdata(dev, NULL); |
| kfree(adapter); |
| |
| return 0; |
| } |
| |
| |
| static int __devinit i2c_powermac_probe(struct platform_device *dev) |
| { |
| struct pmac_i2c_bus *bus = dev->dev.platform_data; |
| struct device_node *parent = NULL; |
| struct i2c_adapter *adapter; |
| char name[32]; |
| const char *basename; |
| int rc; |
| |
| if (bus == NULL) |
| return -EINVAL; |
| |
| /* Ok, now we need to make up a name for the interface that will |
| * match what we used to do in the past, that is basically the |
| * controller's parent device node for keywest. PMU didn't have a |
| * naming convention and SMU has a different one |
| */ |
| switch(pmac_i2c_get_type(bus)) { |
| case pmac_i2c_bus_keywest: |
| parent = of_get_parent(pmac_i2c_get_controller(bus)); |
| if (parent == NULL) |
| return -EINVAL; |
| basename = parent->name; |
| break; |
| case pmac_i2c_bus_pmu: |
| basename = "pmu"; |
| break; |
| case pmac_i2c_bus_smu: |
| /* This is not what we used to do but I'm fixing drivers at |
| * the same time as this change |
| */ |
| basename = "smu"; |
| break; |
| default: |
| return -EINVAL; |
| } |
| snprintf(name, 32, "%s %d", basename, pmac_i2c_get_channel(bus)); |
| of_node_put(parent); |
| |
| adapter = kzalloc(sizeof(struct i2c_adapter), GFP_KERNEL); |
| if (adapter == NULL) { |
| printk(KERN_ERR "i2c-powermac: can't allocate inteface !\n"); |
| return -ENOMEM; |
| } |
| platform_set_drvdata(dev, adapter); |
| strcpy(adapter->name, name); |
| adapter->algo = &i2c_powermac_algorithm; |
| i2c_set_adapdata(adapter, bus); |
| adapter->dev.parent = &dev->dev; |
| pmac_i2c_attach_adapter(bus, adapter); |
| rc = i2c_add_adapter(adapter); |
| if (rc) { |
| printk(KERN_ERR "i2c-powermac: Adapter %s registration " |
| "failed\n", name); |
| i2c_set_adapdata(adapter, NULL); |
| pmac_i2c_detach_adapter(bus, adapter); |
| } |
| |
| printk(KERN_INFO "PowerMac i2c bus %s registered\n", name); |
| |
| if (!strncmp(basename, "uni-n", 5)) { |
| struct device_node *np; |
| const u32 *prop; |
| struct i2c_board_info info; |
| |
| /* Instantiate I2C motion sensor if present */ |
| np = of_find_node_by_name(NULL, "accelerometer"); |
| if (np && of_device_is_compatible(np, "AAPL,accelerometer_1") && |
| (prop = of_get_property(np, "reg", NULL))) { |
| int i2c_bus; |
| const char *tmp_bus; |
| |
| /* look for bus either using "reg" or by path */ |
| tmp_bus = strstr(np->full_name, "/i2c-bus@"); |
| if (tmp_bus) |
| i2c_bus = *(tmp_bus + 9) - '0'; |
| else |
| i2c_bus = ((*prop) >> 8) & 0x0f; |
| |
| if (pmac_i2c_get_channel(bus) == i2c_bus) { |
| memset(&info, 0, sizeof(struct i2c_board_info)); |
| info.addr = ((*prop) & 0xff) >> 1; |
| strlcpy(info.type, "ams", I2C_NAME_SIZE); |
| i2c_new_device(adapter, &info); |
| } |
| } |
| } |
| |
| return rc; |
| } |
| |
| |
| /* work with hotplug and coldplug */ |
| MODULE_ALIAS("platform:i2c-powermac"); |
| |
| static struct platform_driver i2c_powermac_driver = { |
| .probe = i2c_powermac_probe, |
| .remove = __devexit_p(i2c_powermac_remove), |
| .driver = { |
| .name = "i2c-powermac", |
| .bus = &platform_bus_type, |
| }, |
| }; |
| |
| static int __init i2c_powermac_init(void) |
| { |
| platform_driver_register(&i2c_powermac_driver); |
| return 0; |
| } |
| |
| |
| static void __exit i2c_powermac_cleanup(void) |
| { |
| platform_driver_unregister(&i2c_powermac_driver); |
| } |
| |
| module_init(i2c_powermac_init); |
| module_exit(i2c_powermac_cleanup); |