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linux/drivers/mfd/max8998.c
MyungJoo Ham 337ce5d1c5 mfd: Support LP3974 RTC
The first releases of LP3974 have a large delay in RTC registers,
which requires 2 seconds of delay after writing to a rtc register
(recommended by National Semiconductor's engineers)
before reading it.

If "rtc_delay" field of the platform data is true, the rtc driver
assumes that such delays are required. Although we have not seen
LP3974s without requiring such delays, we assume that such LP3974s
will be released soon (or they have done so already) and they are
supported by "lp3974" without setting "rtc_delay" at the platform
data.

This patch adds delays with msleep when writing values to RTC registers
if the platform data has rtc_delay set.

Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2011-01-14 12:38:16 +01:00

335 lines
8.3 KiB
C

/*
* max8998.c - mfd core driver for the Maxim 8998
*
* Copyright (C) 2009-2010 Samsung Electronics
* Kyungmin Park <kyungmin.park@samsung.com>
* Marek Szyprowski <m.szyprowski@samsung.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.
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/pm_runtime.h>
#include <linux/mutex.h>
#include <linux/mfd/core.h>
#include <linux/mfd/max8998.h>
#include <linux/mfd/max8998-private.h>
#define RTC_I2C_ADDR (0x0c >> 1)
static struct mfd_cell max8998_devs[] = {
{
.name = "max8998-pmic",
}, {
.name = "max8998-rtc",
},
};
static struct mfd_cell lp3974_devs[] = {
{
.name = "lp3974-pmic",
}, {
.name = "lp3974-rtc",
},
};
int max8998_read_reg(struct i2c_client *i2c, u8 reg, u8 *dest)
{
struct max8998_dev *max8998 = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&max8998->iolock);
ret = i2c_smbus_read_byte_data(i2c, reg);
mutex_unlock(&max8998->iolock);
if (ret < 0)
return ret;
ret &= 0xff;
*dest = ret;
return 0;
}
EXPORT_SYMBOL(max8998_read_reg);
int max8998_bulk_read(struct i2c_client *i2c, u8 reg, int count, u8 *buf)
{
struct max8998_dev *max8998 = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&max8998->iolock);
ret = i2c_smbus_read_i2c_block_data(i2c, reg, count, buf);
mutex_unlock(&max8998->iolock);
if (ret < 0)
return ret;
return 0;
}
EXPORT_SYMBOL(max8998_bulk_read);
int max8998_write_reg(struct i2c_client *i2c, u8 reg, u8 value)
{
struct max8998_dev *max8998 = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&max8998->iolock);
ret = i2c_smbus_write_byte_data(i2c, reg, value);
mutex_unlock(&max8998->iolock);
return ret;
}
EXPORT_SYMBOL(max8998_write_reg);
int max8998_bulk_write(struct i2c_client *i2c, u8 reg, int count, u8 *buf)
{
struct max8998_dev *max8998 = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&max8998->iolock);
ret = i2c_smbus_write_i2c_block_data(i2c, reg, count, buf);
mutex_unlock(&max8998->iolock);
if (ret < 0)
return ret;
return 0;
}
EXPORT_SYMBOL(max8998_bulk_write);
int max8998_update_reg(struct i2c_client *i2c, u8 reg, u8 val, u8 mask)
{
struct max8998_dev *max8998 = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&max8998->iolock);
ret = i2c_smbus_read_byte_data(i2c, reg);
if (ret >= 0) {
u8 old_val = ret & 0xff;
u8 new_val = (val & mask) | (old_val & (~mask));
ret = i2c_smbus_write_byte_data(i2c, reg, new_val);
}
mutex_unlock(&max8998->iolock);
return ret;
}
EXPORT_SYMBOL(max8998_update_reg);
static int max8998_i2c_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
struct max8998_platform_data *pdata = i2c->dev.platform_data;
struct max8998_dev *max8998;
int ret = 0;
max8998 = kzalloc(sizeof(struct max8998_dev), GFP_KERNEL);
if (max8998 == NULL)
return -ENOMEM;
i2c_set_clientdata(i2c, max8998);
max8998->dev = &i2c->dev;
max8998->i2c = i2c;
max8998->irq = i2c->irq;
max8998->type = id->driver_data;
if (pdata) {
max8998->ono = pdata->ono;
max8998->irq_base = pdata->irq_base;
max8998->wakeup = pdata->wakeup;
}
mutex_init(&max8998->iolock);
max8998->rtc = i2c_new_dummy(i2c->adapter, RTC_I2C_ADDR);
i2c_set_clientdata(max8998->rtc, max8998);
max8998_irq_init(max8998);
pm_runtime_set_active(max8998->dev);
switch (id->driver_data) {
case TYPE_LP3974:
ret = mfd_add_devices(max8998->dev, -1,
lp3974_devs, ARRAY_SIZE(lp3974_devs),
NULL, 0);
break;
case TYPE_MAX8998:
ret = mfd_add_devices(max8998->dev, -1,
max8998_devs, ARRAY_SIZE(max8998_devs),
NULL, 0);
break;
default:
ret = -EINVAL;
}
if (ret < 0)
goto err;
return ret;
err:
mfd_remove_devices(max8998->dev);
max8998_irq_exit(max8998);
i2c_unregister_device(max8998->rtc);
kfree(max8998);
return ret;
}
static int max8998_i2c_remove(struct i2c_client *i2c)
{
struct max8998_dev *max8998 = i2c_get_clientdata(i2c);
mfd_remove_devices(max8998->dev);
max8998_irq_exit(max8998);
i2c_unregister_device(max8998->rtc);
kfree(max8998);
return 0;
}
static const struct i2c_device_id max8998_i2c_id[] = {
{ "max8998", TYPE_MAX8998 },
{ "lp3974", TYPE_LP3974},
{ }
};
MODULE_DEVICE_TABLE(i2c, max8998_i2c_id);
static int max8998_suspend(struct device *dev)
{
struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
struct max8998_dev *max8998 = i2c_get_clientdata(i2c);
if (max8998->wakeup)
set_irq_wake(max8998->irq, 1);
return 0;
}
static int max8998_resume(struct device *dev)
{
struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
struct max8998_dev *max8998 = i2c_get_clientdata(i2c);
if (max8998->wakeup)
set_irq_wake(max8998->irq, 0);
/*
* In LP3974, if IRQ registers are not "read & clear"
* when it's set during sleep, the interrupt becomes
* disabled.
*/
return max8998_irq_resume(i2c_get_clientdata(i2c));
}
struct max8998_reg_dump {
u8 addr;
u8 val;
};
#define SAVE_ITEM(x) { .addr = (x), .val = 0x0, }
struct max8998_reg_dump max8998_dump[] = {
SAVE_ITEM(MAX8998_REG_IRQM1),
SAVE_ITEM(MAX8998_REG_IRQM2),
SAVE_ITEM(MAX8998_REG_IRQM3),
SAVE_ITEM(MAX8998_REG_IRQM4),
SAVE_ITEM(MAX8998_REG_STATUSM1),
SAVE_ITEM(MAX8998_REG_STATUSM2),
SAVE_ITEM(MAX8998_REG_CHGR1),
SAVE_ITEM(MAX8998_REG_CHGR2),
SAVE_ITEM(MAX8998_REG_LDO_ACTIVE_DISCHARGE1),
SAVE_ITEM(MAX8998_REG_LDO_ACTIVE_DISCHARGE1),
SAVE_ITEM(MAX8998_REG_BUCK_ACTIVE_DISCHARGE3),
SAVE_ITEM(MAX8998_REG_ONOFF1),
SAVE_ITEM(MAX8998_REG_ONOFF2),
SAVE_ITEM(MAX8998_REG_ONOFF3),
SAVE_ITEM(MAX8998_REG_ONOFF4),
SAVE_ITEM(MAX8998_REG_BUCK1_VOLTAGE1),
SAVE_ITEM(MAX8998_REG_BUCK1_VOLTAGE2),
SAVE_ITEM(MAX8998_REG_BUCK1_VOLTAGE3),
SAVE_ITEM(MAX8998_REG_BUCK1_VOLTAGE4),
SAVE_ITEM(MAX8998_REG_BUCK2_VOLTAGE1),
SAVE_ITEM(MAX8998_REG_BUCK2_VOLTAGE2),
SAVE_ITEM(MAX8998_REG_LDO2_LDO3),
SAVE_ITEM(MAX8998_REG_LDO4),
SAVE_ITEM(MAX8998_REG_LDO5),
SAVE_ITEM(MAX8998_REG_LDO6),
SAVE_ITEM(MAX8998_REG_LDO7),
SAVE_ITEM(MAX8998_REG_LDO8_LDO9),
SAVE_ITEM(MAX8998_REG_LDO10_LDO11),
SAVE_ITEM(MAX8998_REG_LDO12),
SAVE_ITEM(MAX8998_REG_LDO13),
SAVE_ITEM(MAX8998_REG_LDO14),
SAVE_ITEM(MAX8998_REG_LDO15),
SAVE_ITEM(MAX8998_REG_LDO16),
SAVE_ITEM(MAX8998_REG_LDO17),
SAVE_ITEM(MAX8998_REG_BKCHR),
SAVE_ITEM(MAX8998_REG_LBCNFG1),
SAVE_ITEM(MAX8998_REG_LBCNFG2),
};
/* Save registers before hibernation */
static int max8998_freeze(struct device *dev)
{
struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
int i;
for (i = 0; i < ARRAY_SIZE(max8998_dump); i++)
max8998_read_reg(i2c, max8998_dump[i].addr,
&max8998_dump[i].val);
return 0;
}
/* Restore registers after hibernation */
static int max8998_restore(struct device *dev)
{
struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
int i;
for (i = 0; i < ARRAY_SIZE(max8998_dump); i++)
max8998_write_reg(i2c, max8998_dump[i].addr,
max8998_dump[i].val);
return 0;
}
const struct dev_pm_ops max8998_pm = {
.suspend = max8998_suspend,
.resume = max8998_resume,
.freeze = max8998_freeze,
.restore = max8998_restore,
};
static struct i2c_driver max8998_i2c_driver = {
.driver = {
.name = "max8998",
.owner = THIS_MODULE,
.pm = &max8998_pm,
},
.probe = max8998_i2c_probe,
.remove = max8998_i2c_remove,
.id_table = max8998_i2c_id,
};
static int __init max8998_i2c_init(void)
{
return i2c_add_driver(&max8998_i2c_driver);
}
/* init early so consumer devices can complete system boot */
subsys_initcall(max8998_i2c_init);
static void __exit max8998_i2c_exit(void)
{
i2c_del_driver(&max8998_i2c_driver);
}
module_exit(max8998_i2c_exit);
MODULE_DESCRIPTION("MAXIM 8998 multi-function core driver");
MODULE_AUTHOR("Kyungmin Park <kyungmin.park@samsung.com>");
MODULE_LICENSE("GPL");