/*
* wm8994-gpio.c -- gpiolib support for Wolfson WM8994
*
* Copyright 2009 Wolfson Microelectronics PLC.
*
* Author: Mark Brown <broonie@opensource.wolfsonmicro.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/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/gpio.h>
#include <linux/mfd/core.h>
#include <linux/platform_device.h>
#include <linux/seq_file.h>
#include <linux/mfd/wm8994/core.h>
#include <linux/mfd/wm8994/pdata.h>
#include <linux/mfd/wm8994/gpio.h>
#include <linux/mfd/wm8994/registers.h>
struct wm8994_gpio {
struct wm8994 *wm8994;
struct gpio_chip gpio_chip;
};
static inline struct wm8994_gpio *to_wm8994_gpio(struct gpio_chip *chip)
{
return container_of(chip, struct wm8994_gpio, gpio_chip);
}
static int wm8994_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
{
struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
struct wm8994 *wm8994 = wm8994_gpio->wm8994;
return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
WM8994_GPN_DIR, WM8994_GPN_DIR);
}
static int wm8994_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
struct wm8994 *wm8994 = wm8994_gpio->wm8994;
int ret;
ret = wm8994_reg_read(wm8994, WM8994_GPIO_1 + offset);
if (ret < 0)
return ret;
if (ret & WM8994_GPN_LVL)
return 1;
else
return 0;
}
static int wm8994_gpio_direction_out(struct gpio_chip *chip,
unsigned offset, int value)
{
struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
struct wm8994 *wm8994 = wm8994_gpio->wm8994;
return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
WM8994_GPN_DIR, 0);
}
static void wm8994_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
struct wm8994 *wm8994 = wm8994_gpio->wm8994;
if (value)
value = WM8994_GPN_LVL;
wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, WM8994_GPN_LVL, value);
}
#ifdef CONFIG_DEBUG_FS
static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
struct wm8994 *wm8994 = wm8994_gpio->wm8994;
int i;
for (i = 0; i < chip->ngpio; i++) {
int gpio = i + chip->base;
int reg;
const char *label;
/* We report the GPIO even if it's not requested since
* we're also reporting things like alternate
* functions which apply even when the GPIO is not in
* use as a GPIO.
*/
label = gpiochip_is_requested(chip, i);
if (!label)
label = "Unrequested";
seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i);
if (reg < 0) {
dev_err(wm8994->dev,
"GPIO control %d read failed: %d\n",
gpio, reg);
seq_printf(s, "\n");
continue;
}
/* No decode yet; note that GPIO2 is special */
seq_printf(s, "(%x)\n", reg);
}
}
#else
#define wm8994_gpio_dbg_show NULL
#endif
static struct gpio_chip template_chip = {
.label = "wm8994",
.owner = THIS_MODULE,
.direction_input = wm8994_gpio_direction_in,
.get = wm8994_gpio_get,
.direction_output = wm8994_gpio_direction_out,
.set = wm8994_gpio_set,
.dbg_show = wm8994_gpio_dbg_show,
.can_sleep = 1,
};
static int __devinit wm8994_gpio_probe(struct platform_device *pdev)
{
struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
struct wm8994_pdata *pdata = wm8994->dev->platform_data;
struct wm8994_gpio *wm8994_gpio;
int ret;
wm8994_gpio = kzalloc(sizeof(*wm8994_gpio), GFP_KERNEL);
if (wm8994_gpio == NULL)
return -ENOMEM;
wm8994_gpio->wm8994 = wm8994;
wm8994_gpio->gpio_chip = template_chip;
wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX;
wm8994_gpio->gpio_chip.dev = &pdev->dev;
if (pdata && pdata->gpio_base)
wm8994_gpio->gpio_chip.base = pdata->gpio_base;
else
wm8994_gpio->gpio_chip.base = -1;
ret = gpiochip_add(&wm8994_gpio->gpio_chip);
if (ret < 0) {
dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
ret);
goto err;
}
platform_set_drvdata(pdev, wm8994_gpio);
return ret;
err:
kfree(wm8994_gpio);
return ret;
}
static int __devexit wm8994_gpio_remove(struct platform_device *pdev)
{
struct wm8994_gpio *wm8994_gpio = platform_get_drvdata(pdev);
int ret;
ret = gpiochip_remove(&wm8994_gpio->gpio_chip);
if (ret == 0)
kfree(wm8994_gpio);
return ret;
}
static struct platform_driver wm8994_gpio_driver = {
.driver.name = "wm8994-gpio",
.driver.owner = THIS_MODULE,
.probe = wm8994_gpio_probe,
.remove = __devexit_p(wm8994_gpio_remove),
};
static int __init wm8994_gpio_init(void)
{
return platform_driver_register(&wm8994_gpio_driver);
}
subsys_initcall(wm8994_gpio_init);
static void __exit wm8994_gpio_exit(void)
{
platform_driver_unregister(&wm8994_gpio_driver);
}
module_exit(wm8994_gpio_exit);
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
MODULE_DESCRIPTION("GPIO interface for WM8994");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm8994-gpio");
