2010-10-28 06:33:18 +08:00
|
|
|
/*
|
|
|
|
* 74Hx164 - Generic serial-in/parallel-out 8-bits shift register GPIO driver
|
|
|
|
*
|
|
|
|
* Copyright (C) 2010 Gabor Juhos <juhosg@openwrt.org>
|
|
|
|
* Copyright (C) 2010 Miguel Gaio <miguel.gaio@efixo.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/init.h>
|
|
|
|
#include <linux/mutex.h>
|
|
|
|
#include <linux/spi/spi.h>
|
|
|
|
#include <linux/spi/74x164.h>
|
|
|
|
#include <linux/gpio.h>
|
|
|
|
#include <linux/slab.h>
|
2011-07-04 01:38:09 +08:00
|
|
|
#include <linux/module.h>
|
2010-10-28 06:33:18 +08:00
|
|
|
|
|
|
|
struct gen_74x164_chip {
|
|
|
|
struct spi_device *spi;
|
|
|
|
struct gpio_chip gpio_chip;
|
|
|
|
struct mutex lock;
|
|
|
|
u8 port_config;
|
|
|
|
};
|
|
|
|
|
2011-06-13 16:47:15 +08:00
|
|
|
static struct gen_74x164_chip *gpio_to_74x164_chip(struct gpio_chip *gc)
|
2010-10-28 06:33:18 +08:00
|
|
|
{
|
|
|
|
return container_of(gc, struct gen_74x164_chip, gpio_chip);
|
|
|
|
}
|
|
|
|
|
|
|
|
static int __gen_74x164_write_config(struct gen_74x164_chip *chip)
|
|
|
|
{
|
|
|
|
return spi_write(chip->spi,
|
|
|
|
&chip->port_config, sizeof(chip->port_config));
|
|
|
|
}
|
|
|
|
|
|
|
|
static int gen_74x164_get_value(struct gpio_chip *gc, unsigned offset)
|
|
|
|
{
|
2011-06-13 16:47:15 +08:00
|
|
|
struct gen_74x164_chip *chip = gpio_to_74x164_chip(gc);
|
2010-10-28 06:33:18 +08:00
|
|
|
int ret;
|
|
|
|
|
|
|
|
mutex_lock(&chip->lock);
|
|
|
|
ret = (chip->port_config >> offset) & 0x1;
|
|
|
|
mutex_unlock(&chip->lock);
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void gen_74x164_set_value(struct gpio_chip *gc,
|
|
|
|
unsigned offset, int val)
|
|
|
|
{
|
2011-06-13 16:47:15 +08:00
|
|
|
struct gen_74x164_chip *chip = gpio_to_74x164_chip(gc);
|
2010-10-28 06:33:18 +08:00
|
|
|
|
|
|
|
mutex_lock(&chip->lock);
|
|
|
|
if (val)
|
|
|
|
chip->port_config |= (1 << offset);
|
|
|
|
else
|
|
|
|
chip->port_config &= ~(1 << offset);
|
|
|
|
|
|
|
|
__gen_74x164_write_config(chip);
|
|
|
|
mutex_unlock(&chip->lock);
|
|
|
|
}
|
|
|
|
|
2011-05-28 07:35:59 +08:00
|
|
|
static int gen_74x164_direction_output(struct gpio_chip *gc,
|
|
|
|
unsigned offset, int val)
|
|
|
|
{
|
|
|
|
gen_74x164_set_value(gc, offset, val);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2010-10-28 06:33:18 +08:00
|
|
|
static int __devinit gen_74x164_probe(struct spi_device *spi)
|
|
|
|
{
|
|
|
|
struct gen_74x164_chip *chip;
|
|
|
|
struct gen_74x164_chip_platform_data *pdata;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* bits_per_word cannot be configured in platform data
|
|
|
|
*/
|
|
|
|
spi->bits_per_word = 8;
|
|
|
|
|
|
|
|
ret = spi_setup(spi);
|
|
|
|
if (ret < 0)
|
|
|
|
return ret;
|
|
|
|
|
2012-09-05 16:40:51 +08:00
|
|
|
chip = devm_kzalloc(&spi->dev, sizeof(*chip), GFP_KERNEL);
|
2010-10-28 06:33:18 +08:00
|
|
|
if (!chip)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
2012-09-07 20:18:12 +08:00
|
|
|
pdata = spi->dev.platform_data;
|
|
|
|
if (pdata && pdata->base)
|
|
|
|
chip->gpio_chip.base = pdata->base;
|
|
|
|
else
|
|
|
|
chip->gpio_chip.base = -1;
|
|
|
|
|
2010-10-28 06:33:18 +08:00
|
|
|
mutex_init(&chip->lock);
|
|
|
|
|
|
|
|
dev_set_drvdata(&spi->dev, chip);
|
|
|
|
|
|
|
|
chip->spi = spi;
|
|
|
|
|
2011-05-28 07:35:59 +08:00
|
|
|
chip->gpio_chip.label = spi->modalias;
|
|
|
|
chip->gpio_chip.direction_output = gen_74x164_direction_output;
|
2010-10-28 06:33:18 +08:00
|
|
|
chip->gpio_chip.get = gen_74x164_get_value;
|
|
|
|
chip->gpio_chip.set = gen_74x164_set_value;
|
2011-05-28 07:35:59 +08:00
|
|
|
chip->gpio_chip.ngpio = 8;
|
2010-10-28 06:33:18 +08:00
|
|
|
chip->gpio_chip.can_sleep = 1;
|
|
|
|
chip->gpio_chip.dev = &spi->dev;
|
|
|
|
chip->gpio_chip.owner = THIS_MODULE;
|
|
|
|
|
|
|
|
ret = __gen_74x164_write_config(chip);
|
|
|
|
if (ret) {
|
|
|
|
dev_err(&spi->dev, "Failed writing: %d\n", ret);
|
|
|
|
goto exit_destroy;
|
|
|
|
}
|
|
|
|
|
|
|
|
ret = gpiochip_add(&chip->gpio_chip);
|
|
|
|
if (ret)
|
|
|
|
goto exit_destroy;
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
|
|
|
|
exit_destroy:
|
|
|
|
dev_set_drvdata(&spi->dev, NULL);
|
|
|
|
mutex_destroy(&chip->lock);
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
2011-03-10 17:10:45 +08:00
|
|
|
static int __devexit gen_74x164_remove(struct spi_device *spi)
|
2010-10-28 06:33:18 +08:00
|
|
|
{
|
|
|
|
struct gen_74x164_chip *chip;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
chip = dev_get_drvdata(&spi->dev);
|
|
|
|
if (chip == NULL)
|
|
|
|
return -ENODEV;
|
|
|
|
|
|
|
|
dev_set_drvdata(&spi->dev, NULL);
|
|
|
|
|
|
|
|
ret = gpiochip_remove(&chip->gpio_chip);
|
2012-09-05 16:40:51 +08:00
|
|
|
if (!ret)
|
2010-10-28 06:33:18 +08:00
|
|
|
mutex_destroy(&chip->lock);
|
2012-09-05 16:40:51 +08:00
|
|
|
else
|
2010-10-28 06:33:18 +08:00
|
|
|
dev_err(&spi->dev, "Failed to remove the GPIO controller: %d\n",
|
|
|
|
ret);
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
2012-09-07 20:18:13 +08:00
|
|
|
static const struct of_device_id gen_74x164_dt_ids[] = {
|
|
|
|
{ .compatible = "fairchild,74hc595" },
|
|
|
|
{},
|
|
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(of, gen_74x164_dt_ids);
|
|
|
|
|
2010-10-28 06:33:18 +08:00
|
|
|
static struct spi_driver gen_74x164_driver = {
|
|
|
|
.driver = {
|
2011-05-28 07:35:59 +08:00
|
|
|
.name = "74x164",
|
2010-10-28 06:33:18 +08:00
|
|
|
.owner = THIS_MODULE,
|
2012-09-07 20:18:13 +08:00
|
|
|
.of_match_table = of_match_ptr(gen_74x164_dt_ids),
|
2010-10-28 06:33:18 +08:00
|
|
|
},
|
|
|
|
.probe = gen_74x164_probe,
|
|
|
|
.remove = __devexit_p(gen_74x164_remove),
|
|
|
|
};
|
2012-09-05 16:40:50 +08:00
|
|
|
module_spi_driver(gen_74x164_driver);
|
2010-10-28 06:33:18 +08:00
|
|
|
|
|
|
|
MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
|
|
|
|
MODULE_AUTHOR("Miguel Gaio <miguel.gaio@efixo.com>");
|
|
|
|
MODULE_DESCRIPTION("GPIO expander driver for 74X164 8-bits shift register");
|
|
|
|
MODULE_LICENSE("GPL v2");
|