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linux/drivers/mfd/tps65910.c
Jesper Juhl b1224cd113 mfd: Avoid two assignments if failures happen in tps65910_i2c_probe
In drivers/mfd/tps65910.c:tps65910_i2c_probe() there's potential for a
tiny optimization.

We assign to init_data->irq and init_data->irq_base long before we
need them, and there are two potential exits from the function before
they are needed.

Moving the assignments below these two potential exits means we
completely avoid doing them in these two (failure) cases.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Graeme Gregory <gg@slimlogic.co.uk>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2011-07-31 23:28:26 +02:00

235 lines
5.1 KiB
C

/*
* tps65910.c -- TI TPS6591x
*
* Copyright 2010 Texas Instruments Inc.
*
* Author: Graeme Gregory <gg@slimlogic.co.uk>
* Author: Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>
*
* 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/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/gpio.h>
#include <linux/mfd/core.h>
#include <linux/mfd/tps65910.h>
static struct mfd_cell tps65910s[] = {
{
.name = "tps65910-pmic",
},
{
.name = "tps65910-rtc",
},
{
.name = "tps65910-power",
},
};
static int tps65910_i2c_read(struct tps65910 *tps65910, u8 reg,
int bytes, void *dest)
{
struct i2c_client *i2c = tps65910->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 tps65910_i2c_write(struct tps65910 *tps65910, u8 reg,
int bytes, void *src)
{
struct i2c_client *i2c = tps65910->i2c_client;
/* we add 1 byte for device register */
u8 msg[TPS65910_MAX_REGISTER + 1];
int ret;
if (bytes > TPS65910_MAX_REGISTER)
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;
}
int tps65910_set_bits(struct tps65910 *tps65910, u8 reg, u8 mask)
{
u8 data;
int err;
mutex_lock(&tps65910->io_mutex);
err = tps65910_i2c_read(tps65910, reg, 1, &data);
if (err) {
dev_err(tps65910->dev, "read from reg %x failed\n", reg);
goto out;
}
data |= mask;
err = tps65910_i2c_write(tps65910, reg, 1, &data);
if (err)
dev_err(tps65910->dev, "write to reg %x failed\n", reg);
out:
mutex_unlock(&tps65910->io_mutex);
return err;
}
EXPORT_SYMBOL_GPL(tps65910_set_bits);
int tps65910_clear_bits(struct tps65910 *tps65910, u8 reg, u8 mask)
{
u8 data;
int err;
mutex_lock(&tps65910->io_mutex);
err = tps65910_i2c_read(tps65910, reg, 1, &data);
if (err) {
dev_err(tps65910->dev, "read from reg %x failed\n", reg);
goto out;
}
data &= mask;
err = tps65910_i2c_write(tps65910, reg, 1, &data);
if (err)
dev_err(tps65910->dev, "write to reg %x failed\n", reg);
out:
mutex_unlock(&tps65910->io_mutex);
return err;
}
EXPORT_SYMBOL_GPL(tps65910_clear_bits);
static int tps65910_i2c_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
struct tps65910 *tps65910;
struct tps65910_board *pmic_plat_data;
struct tps65910_platform_data *init_data;
int ret = 0;
pmic_plat_data = dev_get_platdata(&i2c->dev);
if (!pmic_plat_data)
return -EINVAL;
init_data = kzalloc(sizeof(struct tps65910_platform_data), GFP_KERNEL);
if (init_data == NULL)
return -ENOMEM;
tps65910 = kzalloc(sizeof(struct tps65910), GFP_KERNEL);
if (tps65910 == NULL) {
kfree(init_data);
return -ENOMEM;
}
i2c_set_clientdata(i2c, tps65910);
tps65910->dev = &i2c->dev;
tps65910->i2c_client = i2c;
tps65910->id = id->driver_data;
tps65910->read = tps65910_i2c_read;
tps65910->write = tps65910_i2c_write;
mutex_init(&tps65910->io_mutex);
ret = mfd_add_devices(tps65910->dev, -1,
tps65910s, ARRAY_SIZE(tps65910s),
NULL, 0);
if (ret < 0)
goto err;
init_data->irq = pmic_plat_data->irq;
init_data->irq_base = pmic_plat_data->irq;
tps65910_gpio_init(tps65910, pmic_plat_data->gpio_base);
ret = tps65910_irq_init(tps65910, init_data->irq, init_data);
if (ret < 0)
goto err;
kfree(init_data);
return ret;
err:
mfd_remove_devices(tps65910->dev);
kfree(tps65910);
kfree(init_data);
return ret;
}
static int tps65910_i2c_remove(struct i2c_client *i2c)
{
struct tps65910 *tps65910 = i2c_get_clientdata(i2c);
mfd_remove_devices(tps65910->dev);
tps65910_irq_exit(tps65910);
kfree(tps65910);
return 0;
}
static const struct i2c_device_id tps65910_i2c_id[] = {
{ "tps65910", TPS65910 },
{ "tps65911", TPS65911 },
{ }
};
MODULE_DEVICE_TABLE(i2c, tps65910_i2c_id);
static struct i2c_driver tps65910_i2c_driver = {
.driver = {
.name = "tps65910",
.owner = THIS_MODULE,
},
.probe = tps65910_i2c_probe,
.remove = tps65910_i2c_remove,
.id_table = tps65910_i2c_id,
};
static int __init tps65910_i2c_init(void)
{
return i2c_add_driver(&tps65910_i2c_driver);
}
/* init early so consumer devices can complete system boot */
subsys_initcall(tps65910_i2c_init);
static void __exit tps65910_i2c_exit(void)
{
i2c_del_driver(&tps65910_i2c_driver);
}
module_exit(tps65910_i2c_exit);
MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
MODULE_AUTHOR("Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>");
MODULE_DESCRIPTION("TPS6591x chip family multi-function driver");
MODULE_LICENSE("GPL");