alistair23-linux/drivers/regulator/max8649.c
Wolfram Sang fbae3fb154 i2c: Remove all i2c_set_clientdata(client, NULL) in drivers
I2C drivers can use the clientdata-pointer to point to private data. As I2C
devices are not really unregistered, but merely detached from their driver, it
used to be the drivers obligation to clear this pointer during remove() or a
failed probe(). As a couple of drivers forgot to do this, it was agreed that it
was cleaner if the i2c-core does this clearance when appropriate, as there is
no guarantee for the lifetime of the clientdata-pointer after remove() anyhow.
This feature was added to the core with commit
e4a7b9b04d to fix the faulty drivers.

As there is no need anymore to clear the clientdata-pointer, remove all current
occurrences in the drivers to simplify the code and prevent confusion.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-06-03 11:33:58 +02:00

409 lines
9.7 KiB
C

/*
* Regulators driver for Maxim max8649
*
* Copyright (C) 2009-2010 Marvell International Ltd.
* Haojian Zhuang <haojian.zhuang@marvell.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/slab.h>
#include <linux/regulator/max8649.h>
#define MAX8649_DCDC_VMIN 750000 /* uV */
#define MAX8649_DCDC_VMAX 1380000 /* uV */
#define MAX8649_DCDC_STEP 10000 /* uV */
#define MAX8649_VOL_MASK 0x3f
/* Registers */
#define MAX8649_MODE0 0x00
#define MAX8649_MODE1 0x01
#define MAX8649_MODE2 0x02
#define MAX8649_MODE3 0x03
#define MAX8649_CONTROL 0x04
#define MAX8649_SYNC 0x05
#define MAX8649_RAMP 0x06
#define MAX8649_CHIP_ID1 0x08
#define MAX8649_CHIP_ID2 0x09
/* Bits */
#define MAX8649_EN_PD (1 << 7)
#define MAX8649_VID0_PD (1 << 6)
#define MAX8649_VID1_PD (1 << 5)
#define MAX8649_VID_MASK (3 << 5)
#define MAX8649_FORCE_PWM (1 << 7)
#define MAX8649_SYNC_EXTCLK (1 << 6)
#define MAX8649_EXT_MASK (3 << 6)
#define MAX8649_RAMP_MASK (7 << 5)
#define MAX8649_RAMP_DOWN (1 << 1)
struct max8649_regulator_info {
struct regulator_dev *regulator;
struct i2c_client *i2c;
struct device *dev;
struct mutex io_lock;
int vol_reg;
unsigned mode:2; /* bit[1:0] = VID1, VID0 */
unsigned extclk_freq:2;
unsigned extclk:1;
unsigned ramp_timing:3;
unsigned ramp_down:1;
};
/* I2C operations */
static inline int max8649_read_device(struct i2c_client *i2c,
int reg, int bytes, void *dest)
{
unsigned char data;
int ret;
data = (unsigned char)reg;
ret = i2c_master_send(i2c, &data, 1);
if (ret < 0)
return ret;
ret = i2c_master_recv(i2c, dest, bytes);
if (ret < 0)
return ret;
return 0;
}
static inline int max8649_write_device(struct i2c_client *i2c,
int reg, int bytes, void *src)
{
unsigned char buf[bytes + 1];
int ret;
buf[0] = (unsigned char)reg;
memcpy(&buf[1], src, bytes);
ret = i2c_master_send(i2c, buf, bytes + 1);
if (ret < 0)
return ret;
return 0;
}
static int max8649_reg_read(struct i2c_client *i2c, int reg)
{
struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
unsigned char data;
int ret;
mutex_lock(&info->io_lock);
ret = max8649_read_device(i2c, reg, 1, &data);
mutex_unlock(&info->io_lock);
if (ret < 0)
return ret;
return (int)data;
}
static int max8649_set_bits(struct i2c_client *i2c, int reg,
unsigned char mask, unsigned char data)
{
struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
unsigned char value;
int ret;
mutex_lock(&info->io_lock);
ret = max8649_read_device(i2c, reg, 1, &value);
if (ret < 0)
goto out;
value &= ~mask;
value |= data;
ret = max8649_write_device(i2c, reg, 1, &value);
out:
mutex_unlock(&info->io_lock);
return ret;
}
static inline int check_range(int min_uV, int max_uV)
{
if ((min_uV < MAX8649_DCDC_VMIN) || (max_uV > MAX8649_DCDC_VMAX)
|| (min_uV > max_uV))
return -EINVAL;
return 0;
}
static int max8649_list_voltage(struct regulator_dev *rdev, unsigned index)
{
return (MAX8649_DCDC_VMIN + index * MAX8649_DCDC_STEP);
}
static int max8649_get_voltage(struct regulator_dev *rdev)
{
struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
unsigned char data;
int ret;
ret = max8649_reg_read(info->i2c, info->vol_reg);
if (ret < 0)
return ret;
data = (unsigned char)ret & MAX8649_VOL_MASK;
return max8649_list_voltage(rdev, data);
}
static int max8649_set_voltage(struct regulator_dev *rdev,
int min_uV, int max_uV)
{
struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
unsigned char data, mask;
if (check_range(min_uV, max_uV)) {
dev_err(info->dev, "invalid voltage range (%d, %d) uV\n",
min_uV, max_uV);
return -EINVAL;
}
data = (min_uV - MAX8649_DCDC_VMIN + MAX8649_DCDC_STEP - 1)
/ MAX8649_DCDC_STEP;
mask = MAX8649_VOL_MASK;
return max8649_set_bits(info->i2c, info->vol_reg, mask, data);
}
/* EN_PD means pulldown on EN input */
static int max8649_enable(struct regulator_dev *rdev)
{
struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
return max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_EN_PD, 0);
}
/*
* Applied internal pulldown resistor on EN input pin.
* If pulldown EN pin outside, it would be better.
*/
static int max8649_disable(struct regulator_dev *rdev)
{
struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
return max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_EN_PD,
MAX8649_EN_PD);
}
static int max8649_is_enabled(struct regulator_dev *rdev)
{
struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
int ret;
ret = max8649_reg_read(info->i2c, MAX8649_CONTROL);
if (ret < 0)
return ret;
return !((unsigned char)ret & MAX8649_EN_PD);
}
static int max8649_enable_time(struct regulator_dev *rdev)
{
struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
int voltage, rate, ret;
/* get voltage */
ret = max8649_reg_read(info->i2c, info->vol_reg);
if (ret < 0)
return ret;
ret &= MAX8649_VOL_MASK;
voltage = max8649_list_voltage(rdev, (unsigned char)ret); /* uV */
/* get rate */
ret = max8649_reg_read(info->i2c, MAX8649_RAMP);
if (ret < 0)
return ret;
ret = (ret & MAX8649_RAMP_MASK) >> 5;
rate = (32 * 1000) >> ret; /* uV/uS */
return (voltage / rate);
}
static int max8649_set_mode(struct regulator_dev *rdev, unsigned int mode)
{
struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
switch (mode) {
case REGULATOR_MODE_FAST:
max8649_set_bits(info->i2c, info->vol_reg, MAX8649_FORCE_PWM,
MAX8649_FORCE_PWM);
break;
case REGULATOR_MODE_NORMAL:
max8649_set_bits(info->i2c, info->vol_reg,
MAX8649_FORCE_PWM, 0);
break;
default:
return -EINVAL;
}
return 0;
}
static unsigned int max8649_get_mode(struct regulator_dev *rdev)
{
struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
int ret;
ret = max8649_reg_read(info->i2c, info->vol_reg);
if (ret & MAX8649_FORCE_PWM)
return REGULATOR_MODE_FAST;
return REGULATOR_MODE_NORMAL;
}
static struct regulator_ops max8649_dcdc_ops = {
.set_voltage = max8649_set_voltage,
.get_voltage = max8649_get_voltage,
.list_voltage = max8649_list_voltage,
.enable = max8649_enable,
.disable = max8649_disable,
.is_enabled = max8649_is_enabled,
.enable_time = max8649_enable_time,
.set_mode = max8649_set_mode,
.get_mode = max8649_get_mode,
};
static struct regulator_desc dcdc_desc = {
.name = "max8649",
.ops = &max8649_dcdc_ops,
.type = REGULATOR_VOLTAGE,
.n_voltages = 1 << 6,
.owner = THIS_MODULE,
};
static int __devinit max8649_regulator_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct max8649_platform_data *pdata = client->dev.platform_data;
struct max8649_regulator_info *info = NULL;
unsigned char data;
int ret;
info = kzalloc(sizeof(struct max8649_regulator_info), GFP_KERNEL);
if (!info) {
dev_err(&client->dev, "No enough memory\n");
return -ENOMEM;
}
info->i2c = client;
info->dev = &client->dev;
mutex_init(&info->io_lock);
i2c_set_clientdata(client, info);
info->mode = pdata->mode;
switch (info->mode) {
case 0:
info->vol_reg = MAX8649_MODE0;
break;
case 1:
info->vol_reg = MAX8649_MODE1;
break;
case 2:
info->vol_reg = MAX8649_MODE2;
break;
case 3:
info->vol_reg = MAX8649_MODE3;
break;
default:
break;
}
ret = max8649_reg_read(info->i2c, MAX8649_CHIP_ID1);
if (ret < 0) {
dev_err(info->dev, "Failed to detect ID of MAX8649:%d\n",
ret);
goto out;
}
dev_info(info->dev, "Detected MAX8649 (ID:%x)\n", ret);
/* enable VID0 & VID1 */
max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_VID_MASK, 0);
/* enable/disable external clock synchronization */
info->extclk = pdata->extclk;
data = (info->extclk) ? MAX8649_SYNC_EXTCLK : 0;
max8649_set_bits(info->i2c, info->vol_reg, MAX8649_SYNC_EXTCLK, data);
if (info->extclk) {
/* set external clock frequency */
info->extclk_freq = pdata->extclk_freq;
max8649_set_bits(info->i2c, MAX8649_SYNC, MAX8649_EXT_MASK,
info->extclk_freq);
}
if (pdata->ramp_timing) {
info->ramp_timing = pdata->ramp_timing;
max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_MASK,
info->ramp_timing << 5);
}
info->ramp_down = pdata->ramp_down;
if (info->ramp_down) {
max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_DOWN,
MAX8649_RAMP_DOWN);
}
info->regulator = regulator_register(&dcdc_desc, &client->dev,
pdata->regulator, info);
if (IS_ERR(info->regulator)) {
dev_err(info->dev, "failed to register regulator %s\n",
dcdc_desc.name);
ret = PTR_ERR(info->regulator);
goto out;
}
dev_info(info->dev, "Max8649 regulator device is detected.\n");
return 0;
out:
kfree(info);
return ret;
}
static int __devexit max8649_regulator_remove(struct i2c_client *client)
{
struct max8649_regulator_info *info = i2c_get_clientdata(client);
if (info) {
if (info->regulator)
regulator_unregister(info->regulator);
kfree(info);
}
return 0;
}
static const struct i2c_device_id max8649_id[] = {
{ "max8649", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, max8649_id);
static struct i2c_driver max8649_driver = {
.probe = max8649_regulator_probe,
.remove = __devexit_p(max8649_regulator_remove),
.driver = {
.name = "max8649",
},
.id_table = max8649_id,
};
static int __init max8649_init(void)
{
return i2c_add_driver(&max8649_driver);
}
subsys_initcall(max8649_init);
static void __exit max8649_exit(void)
{
i2c_del_driver(&max8649_driver);
}
module_exit(max8649_exit);
/* Module information */
MODULE_DESCRIPTION("MAXIM 8649 voltage regulator driver");
MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
MODULE_LICENSE("GPL");