/*
* Retu MFD driver
*
* Copyright (C) 2004, 2005 Nokia Corporation
*
* Based on code written by Juha Yrjölä, David Weinehall and Mikko Ylinen.
* Rewritten by Aaro Koskinen.
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file "COPYING" in the main directory of this
* archive for more details.
*
* 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.
*/
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/irq.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/mfd/core.h>
#include <linux/mfd/retu.h>
#include <linux/interrupt.h>
#include <linux/moduleparam.h>
/* Registers */
#define RETU_REG_ASICR 0x00 /* ASIC ID and revision */
#define RETU_REG_ASICR_VILMA (1 << 7) /* Bit indicating Vilma */
#define RETU_REG_IDR 0x01 /* Interrupt ID */
#define RETU_REG_IMR 0x02 /* Interrupt mask */
/* Interrupt sources */
#define RETU_INT_PWR 0 /* Power button */
struct retu_dev {
struct regmap *regmap;
struct device *dev;
struct mutex mutex;
struct regmap_irq_chip_data *irq_data;
};
static struct resource retu_pwrbutton_res[] = {
{
.name = "retu-pwrbutton",
.start = RETU_INT_PWR,
.end = RETU_INT_PWR,
.flags = IORESOURCE_IRQ,
},
};
static struct mfd_cell retu_devs[] = {
{
.name = "retu-wdt"
},
{
.name = "retu-pwrbutton",
.resources = retu_pwrbutton_res,
.num_resources = ARRAY_SIZE(retu_pwrbutton_res),
}
};
static struct regmap_irq retu_irqs[] = {
[RETU_INT_PWR] = {
.mask = 1 << RETU_INT_PWR,
}
};
static struct regmap_irq_chip retu_irq_chip = {
.name = "RETU",
.irqs = retu_irqs,
.num_irqs = ARRAY_SIZE(retu_irqs),
.num_regs = 1,
.status_base = RETU_REG_IDR,
.mask_base = RETU_REG_IMR,
.ack_base = RETU_REG_IDR,
};
/* Retu device registered for the power off. */
static struct retu_dev *retu_pm_power_off;
int retu_read(struct retu_dev *rdev, u8 reg)
{
int ret;
int value;
mutex_lock(&rdev->mutex);
ret = regmap_read(rdev->regmap, reg, &value);
mutex_unlock(&rdev->mutex);
return ret ? ret : value;
}
EXPORT_SYMBOL_GPL(retu_read);
int retu_write(struct retu_dev *rdev, u8 reg, u16 data)
{
int ret;
mutex_lock(&rdev->mutex);
ret = regmap_write(rdev->regmap, reg, data);
mutex_unlock(&rdev->mutex);
return ret;
}
EXPORT_SYMBOL_GPL(retu_write);
static void retu_power_off(void)
{
struct retu_dev *rdev = retu_pm_power_off;
int reg;
mutex_lock(&retu_pm_power_off->mutex);
/* Ignore power button state */
regmap_read(rdev->regmap, RETU_REG_CC1, ®);
regmap_write(rdev->regmap, RETU_REG_CC1, reg | 2);
/* Expire watchdog immediately */
regmap_write(rdev->regmap, RETU_REG_WATCHDOG, 0);
/* Wait for poweroff */
for (;;)
cpu_relax();
mutex_unlock(&retu_pm_power_off->mutex);
}
static int retu_regmap_read(void *context, const void *reg, size_t reg_size,
void *val, size_t val_size)
{
int ret;
struct device *dev = context;
struct i2c_client *i2c = to_i2c_client(dev);
BUG_ON(reg_size != 1 || val_size != 2);
ret = i2c_smbus_read_word_data(i2c, *(u8 const *)reg);
if (ret < 0)
return ret;
*(u16 *)val = ret;
return 0;
}
static int retu_regmap_write(void *context, const void *data, size_t count)
{
u8 reg;
u16 val;
struct device *dev = context;
struct i2c_client *i2c = to_i2c_client(dev);
BUG_ON(count != sizeof(reg) + sizeof(val));
memcpy(®, data, sizeof(reg));
memcpy(&val, data + sizeof(reg), sizeof(val));
return i2c_smbus_write_word_data(i2c, reg, val);
}
static struct regmap_bus retu_bus = {
.read = retu_regmap_read,
.write = retu_regmap_write,
.val_format_endian_default = REGMAP_ENDIAN_NATIVE,
};
static struct regmap_config retu_config = {
.reg_bits = 8,
.val_bits = 16,
};
static int __devinit retu_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
struct retu_dev *rdev;
int ret;
rdev = devm_kzalloc(&i2c->dev, sizeof(*rdev), GFP_KERNEL);
if (rdev == NULL)
return -ENOMEM;
i2c_set_clientdata(i2c, rdev);
rdev->dev = &i2c->dev;
mutex_init(&rdev->mutex);
rdev->regmap = devm_regmap_init(&i2c->dev, &retu_bus, &i2c->dev,
&retu_config);
if (IS_ERR(rdev->regmap))
return PTR_ERR(rdev->regmap);
ret = retu_read(rdev, RETU_REG_ASICR);
if (ret < 0) {
dev_err(rdev->dev, "could not read Retu revision: %d\n", ret);
return ret;
}
dev_info(rdev->dev, "Retu%s v%d.%d found\n",
(ret & RETU_REG_ASICR_VILMA) ? " & Vilma" : "",
(ret >> 4) & 0x7, ret & 0xf);
/* Mask all RETU interrupts. */
ret = retu_write(rdev, RETU_REG_IMR, 0xffff);
if (ret < 0)
return ret;
ret = regmap_add_irq_chip(rdev->regmap, i2c->irq, IRQF_ONESHOT, -1,
&retu_irq_chip, &rdev->irq_data);
if (ret < 0)
return ret;
ret = mfd_add_devices(rdev->dev, -1, retu_devs, ARRAY_SIZE(retu_devs),
NULL, regmap_irq_chip_get_base(rdev->irq_data),
NULL);
if (ret < 0) {
regmap_del_irq_chip(i2c->irq, rdev->irq_data);
return ret;
}
if (!pm_power_off) {
retu_pm_power_off = rdev;
pm_power_off = retu_power_off;
}
return 0;
}
static int __devexit retu_remove(struct i2c_client *i2c)
{
struct retu_dev *rdev = i2c_get_clientdata(i2c);
if (retu_pm_power_off == rdev) {
pm_power_off = NULL;
retu_pm_power_off = NULL;
}
mfd_remove_devices(rdev->dev);
regmap_del_irq_chip(i2c->irq, rdev->irq_data);
return 0;
}
static const struct i2c_device_id retu_id[] = {
{ "retu-mfd", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, retu_id);
static struct i2c_driver retu_driver = {
.driver = {
.name = "retu-mfd",
.owner = THIS_MODULE,
},
.probe = retu_probe,
.remove = retu_remove,
.id_table = retu_id,
};
module_i2c_driver(retu_driver);
MODULE_DESCRIPTION("Retu MFD driver");
MODULE_AUTHOR("Juha Yrjölä");
MODULE_AUTHOR("David Weinehall");
MODULE_AUTHOR("Mikko Ylinen");
MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
MODULE_LICENSE("GPL");
