linux/drivers/mfd/tps6507x.c
Todd Fischer 7525996670 input: Touchscreen driver for TPS6507x
Add touch screen input driver for TPS6507x family of multi-function
chips.  Uses the TPS6507x MFD driver.  No interrupt support due to
testing limitations of current hardware.

Signed-off-by: Todd Fischer <todd.fischer@ridgerun.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-05-28 01:37:38 +02:00

159 lines
3.2 KiB
C

/*
* tps6507x.c -- TPS6507x chip family multi-function driver
*
* Copyright (c) 2010 RidgeRun (todd.fischer@ridgerun.com)
*
* Author: Todd Fischer
* todd.fischer@ridgerun.com
*
* Credits:
*
* Using code from wm831x-*.c, wm8400-core, Wolfson Microelectronics PLC.
*
* For licencing details see kernel-base/COPYING
*
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/mfd/core.h>
#include <linux/mfd/tps6507x.h>
static struct mfd_cell tps6507x_devs[] = {
{
.name = "tps6507x-pmic",
},
{
.name = "tps6507x-ts",
},
};
static int tps6507x_i2c_read_device(struct tps6507x_dev *tps6507x, char reg,
int bytes, void *dest)
{
struct i2c_client *i2c = tps6507x->i2c_client;
struct i2c_msg xfer[2];
int ret;
/* Write register */
xfer[0].addr = i2c->addr;
xfer[0].flags = 0;
xfer[0].len = 1;
xfer[0].buf = &reg;
/* Read data */
xfer[1].addr = i2c->addr;
xfer[1].flags = I2C_M_RD;
xfer[1].len = bytes;
xfer[1].buf = dest;
ret = i2c_transfer(i2c->adapter, xfer, 2);
if (ret == 2)
ret = 0;
else if (ret >= 0)
ret = -EIO;
return ret;
}
static int tps6507x_i2c_write_device(struct tps6507x_dev *tps6507x, char reg,
int bytes, void *src)
{
struct i2c_client *i2c = tps6507x->i2c_client;
/* we add 1 byte for device register */
u8 msg[TPS6507X_MAX_REGISTER + 1];
int ret;
if (bytes > (TPS6507X_MAX_REGISTER + 1))
return -EINVAL;
msg[0] = reg;
memcpy(&msg[1], src, bytes);
ret = i2c_master_send(i2c, msg, bytes + 1);
if (ret < 0)
return ret;
if (ret != bytes + 1)
return -EIO;
return 0;
}
static int tps6507x_i2c_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
struct tps6507x_dev *tps6507x;
int ret = 0;
tps6507x = kzalloc(sizeof(struct tps6507x_dev), GFP_KERNEL);
if (tps6507x == NULL) {
kfree(i2c);
return -ENOMEM;
}
i2c_set_clientdata(i2c, tps6507x);
tps6507x->dev = &i2c->dev;
tps6507x->i2c_client = i2c;
tps6507x->read_dev = tps6507x_i2c_read_device;
tps6507x->write_dev = tps6507x_i2c_write_device;
ret = mfd_add_devices(tps6507x->dev, -1,
tps6507x_devs, ARRAY_SIZE(tps6507x_devs),
NULL, 0);
if (ret < 0)
goto err;
return ret;
err:
mfd_remove_devices(tps6507x->dev);
kfree(tps6507x);
return ret;
}
static int tps6507x_i2c_remove(struct i2c_client *i2c)
{
struct tps6507x_dev *tps6507x = i2c_get_clientdata(i2c);
mfd_remove_devices(tps6507x->dev);
kfree(tps6507x);
return 0;
}
static const struct i2c_device_id tps6507x_i2c_id[] = {
{ "tps6507x", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, tps6507x_i2c_id);
static struct i2c_driver tps6507x_i2c_driver = {
.driver = {
.name = "tps6507x",
.owner = THIS_MODULE,
},
.probe = tps6507x_i2c_probe,
.remove = tps6507x_i2c_remove,
.id_table = tps6507x_i2c_id,
};
static int __init tps6507x_i2c_init(void)
{
return i2c_add_driver(&tps6507x_i2c_driver);
}
/* init early so consumer devices can complete system boot */
subsys_initcall(tps6507x_i2c_init);
static void __exit tps6507x_i2c_exit(void)
{
i2c_del_driver(&tps6507x_i2c_driver);
}
module_exit(tps6507x_i2c_exit);
MODULE_DESCRIPTION("TPS6507x chip family multi-function driver");
MODULE_LICENSE("GPL");