2ffe8c5f32
This patch tightens up the behaviour of of_modalias_node() to be more predicatable and to eliminate the explicit of_modalias_tablep[] that is currently used to override the first entry in the compatible list of a device. The override table was needed originally because spi and i2c drivers had no way to do of-style matching. Now that all devices can have an of_node pointer, and all drivers can have an of_match_table, the explicit override table is no longer needed because each driver can specify its own OF-style match data. The mpc8349emitx-mcu driver is modified to explicitly specify the correct device to bind against. Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
194 lines
4.1 KiB
C
194 lines
4.1 KiB
C
/*
|
|
* Power Management and GPIO expander driver for MPC8349E-mITX-compatible MCU
|
|
*
|
|
* Copyright (c) 2008 MontaVista Software, Inc.
|
|
*
|
|
* Author: Anton Vorontsov <avorontsov@ru.mvista.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.
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/device.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/gpio.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_gpio.h>
|
|
#include <linux/slab.h>
|
|
#include <asm/prom.h>
|
|
#include <asm/machdep.h>
|
|
|
|
/*
|
|
* I don't have specifications for the MCU firmware, I found this register
|
|
* and bits positions by the trial&error method.
|
|
*/
|
|
#define MCU_REG_CTRL 0x20
|
|
#define MCU_CTRL_POFF 0x40
|
|
|
|
#define MCU_NUM_GPIO 2
|
|
|
|
struct mcu {
|
|
struct mutex lock;
|
|
struct i2c_client *client;
|
|
struct gpio_chip gc;
|
|
u8 reg_ctrl;
|
|
};
|
|
|
|
static struct mcu *glob_mcu;
|
|
|
|
static void mcu_power_off(void)
|
|
{
|
|
struct mcu *mcu = glob_mcu;
|
|
|
|
pr_info("Sending power-off request to the MCU...\n");
|
|
mutex_lock(&mcu->lock);
|
|
i2c_smbus_write_byte_data(glob_mcu->client, MCU_REG_CTRL,
|
|
mcu->reg_ctrl | MCU_CTRL_POFF);
|
|
mutex_unlock(&mcu->lock);
|
|
}
|
|
|
|
static void mcu_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
|
|
{
|
|
struct mcu *mcu = container_of(gc, struct mcu, gc);
|
|
u8 bit = 1 << (4 + gpio);
|
|
|
|
mutex_lock(&mcu->lock);
|
|
if (val)
|
|
mcu->reg_ctrl &= ~bit;
|
|
else
|
|
mcu->reg_ctrl |= bit;
|
|
|
|
i2c_smbus_write_byte_data(mcu->client, MCU_REG_CTRL, mcu->reg_ctrl);
|
|
mutex_unlock(&mcu->lock);
|
|
}
|
|
|
|
static int mcu_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
|
|
{
|
|
mcu_gpio_set(gc, gpio, val);
|
|
return 0;
|
|
}
|
|
|
|
static int mcu_gpiochip_add(struct mcu *mcu)
|
|
{
|
|
struct device_node *np;
|
|
struct gpio_chip *gc = &mcu->gc;
|
|
|
|
np = of_find_compatible_node(NULL, NULL, "fsl,mcu-mpc8349emitx");
|
|
if (!np)
|
|
return -ENODEV;
|
|
|
|
gc->owner = THIS_MODULE;
|
|
gc->label = np->full_name;
|
|
gc->can_sleep = 1;
|
|
gc->ngpio = MCU_NUM_GPIO;
|
|
gc->base = -1;
|
|
gc->set = mcu_gpio_set;
|
|
gc->direction_output = mcu_gpio_dir_out;
|
|
gc->of_node = np;
|
|
|
|
return gpiochip_add(gc);
|
|
}
|
|
|
|
static int mcu_gpiochip_remove(struct mcu *mcu)
|
|
{
|
|
return gpiochip_remove(&mcu->gc);
|
|
}
|
|
|
|
static int __devinit mcu_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
struct mcu *mcu;
|
|
int ret;
|
|
|
|
mcu = kzalloc(sizeof(*mcu), GFP_KERNEL);
|
|
if (!mcu)
|
|
return -ENOMEM;
|
|
|
|
mutex_init(&mcu->lock);
|
|
mcu->client = client;
|
|
i2c_set_clientdata(client, mcu);
|
|
|
|
ret = i2c_smbus_read_byte_data(mcu->client, MCU_REG_CTRL);
|
|
if (ret < 0)
|
|
goto err;
|
|
mcu->reg_ctrl = ret;
|
|
|
|
ret = mcu_gpiochip_add(mcu);
|
|
if (ret)
|
|
goto err;
|
|
|
|
/* XXX: this is potentially racy, but there is no lock for ppc_md */
|
|
if (!ppc_md.power_off) {
|
|
glob_mcu = mcu;
|
|
ppc_md.power_off = mcu_power_off;
|
|
dev_info(&client->dev, "will provide power-off service\n");
|
|
}
|
|
|
|
return 0;
|
|
err:
|
|
kfree(mcu);
|
|
return ret;
|
|
}
|
|
|
|
static int __devexit mcu_remove(struct i2c_client *client)
|
|
{
|
|
struct mcu *mcu = i2c_get_clientdata(client);
|
|
int ret;
|
|
|
|
if (glob_mcu == mcu) {
|
|
ppc_md.power_off = NULL;
|
|
glob_mcu = NULL;
|
|
}
|
|
|
|
ret = mcu_gpiochip_remove(mcu);
|
|
if (ret)
|
|
return ret;
|
|
i2c_set_clientdata(client, NULL);
|
|
kfree(mcu);
|
|
return 0;
|
|
}
|
|
|
|
static const struct i2c_device_id mcu_ids[] = {
|
|
{ "mcu-mpc8349emitx", },
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, mcu_ids);
|
|
|
|
static struct of_device_id mcu_of_match_table[] __devinitdata = {
|
|
{ .compatible = "fsl,mcu-mpc8349emitx", },
|
|
{ },
|
|
};
|
|
|
|
static struct i2c_driver mcu_driver = {
|
|
.driver = {
|
|
.name = "mcu-mpc8349emitx",
|
|
.owner = THIS_MODULE,
|
|
.of_match_table = mcu_of_match_table,
|
|
},
|
|
.probe = mcu_probe,
|
|
.remove = __devexit_p(mcu_remove),
|
|
.id_table = mcu_ids,
|
|
};
|
|
|
|
static int __init mcu_init(void)
|
|
{
|
|
return i2c_add_driver(&mcu_driver);
|
|
}
|
|
module_init(mcu_init);
|
|
|
|
static void __exit mcu_exit(void)
|
|
{
|
|
i2c_del_driver(&mcu_driver);
|
|
}
|
|
module_exit(mcu_exit);
|
|
|
|
MODULE_DESCRIPTION("Power Management and GPIO expander driver for "
|
|
"MPC8349E-mITX-compatible MCU");
|
|
MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
|
|
MODULE_LICENSE("GPL");
|