diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/mfd/wm831x-i2c.c | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/drivers/mfd/wm831x-i2c.c b/drivers/mfd/wm831x-i2c.c new file mode 100644 index 000000000000..156b19859e81 --- /dev/null +++ b/drivers/mfd/wm831x-i2c.c @@ -0,0 +1,143 @@ +/* + * wm831x-i2c.c -- I2C access for Wolfson WM831x PMICs + * + * Copyright 2009,2010 Wolfson Microelectronics PLC. + * + * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> + * + * 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. + * + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/delay.h> +#include <linux/mfd/core.h> +#include <linux/slab.h> + +#include <linux/mfd/wm831x/core.h> +#include <linux/mfd/wm831x/pdata.h> + +static int wm831x_i2c_read_device(struct wm831x *wm831x, unsigned short reg, + int bytes, void *dest) +{ + struct i2c_client *i2c = wm831x->control_data; + int ret; + u16 r = cpu_to_be16(reg); + + ret = i2c_master_send(i2c, (unsigned char *)&r, 2); + if (ret < 0) + return ret; + if (ret != 2) + return -EIO; + + ret = i2c_master_recv(i2c, dest, bytes); + if (ret < 0) + return ret; + if (ret != bytes) + return -EIO; + return 0; +} + +/* Currently we allocate the write buffer on the stack; this is OK for + * small writes - if we need to do large writes this will need to be + * revised. + */ +static int wm831x_i2c_write_device(struct wm831x *wm831x, unsigned short reg, + int bytes, void *src) +{ + struct i2c_client *i2c = wm831x->control_data; + unsigned char msg[bytes + 2]; + int ret; + + reg = cpu_to_be16(reg); + memcpy(&msg[0], ®, 2); + memcpy(&msg[2], src, bytes); + + ret = i2c_master_send(i2c, msg, bytes + 2); + if (ret < 0) + return ret; + if (ret < bytes + 2) + return -EIO; + + return 0; +} + +static int wm831x_i2c_probe(struct i2c_client *i2c, + const struct i2c_device_id *id) +{ + struct wm831x *wm831x; + + wm831x = kzalloc(sizeof(struct wm831x), GFP_KERNEL); + if (wm831x == NULL) + return -ENOMEM; + + i2c_set_clientdata(i2c, wm831x); + wm831x->dev = &i2c->dev; + wm831x->control_data = i2c; + wm831x->read_dev = wm831x_i2c_read_device; + wm831x->write_dev = wm831x_i2c_write_device; + + return wm831x_device_init(wm831x, id->driver_data, i2c->irq); +} + +static int wm831x_i2c_remove(struct i2c_client *i2c) +{ + struct wm831x *wm831x = i2c_get_clientdata(i2c); + + wm831x_device_exit(wm831x); + + return 0; +} + +static int wm831x_i2c_suspend(struct i2c_client *i2c, pm_message_t mesg) +{ + struct wm831x *wm831x = i2c_get_clientdata(i2c); + + return wm831x_device_suspend(wm831x); +} + +static const struct i2c_device_id wm831x_i2c_id[] = { + { "wm8310", WM8310 }, + { "wm8311", WM8311 }, + { "wm8312", WM8312 }, + { "wm8320", WM8320 }, + { "wm8321", WM8321 }, + { "wm8325", WM8325 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, wm831x_i2c_id); + + +static struct i2c_driver wm831x_i2c_driver = { + .driver = { + .name = "wm831x", + .owner = THIS_MODULE, + }, + .probe = wm831x_i2c_probe, + .remove = wm831x_i2c_remove, + .suspend = wm831x_i2c_suspend, + .id_table = wm831x_i2c_id, +}; + +static int __init wm831x_i2c_init(void) +{ + int ret; + + ret = i2c_add_driver(&wm831x_i2c_driver); + if (ret != 0) + pr_err("Failed to register wm831x I2C driver: %d\n", ret); + + return ret; +} +subsys_initcall(wm831x_i2c_init); + +static void __exit wm831x_i2c_exit(void) +{ + i2c_del_driver(&wm831x_i2c_driver); +} +module_exit(wm831x_i2c_exit); |