linux/drivers/gpio/gpio-arizona.c
Andy Shevchenko 6dbe6c07f9 gpio: Propagate firmware node from a parent device
When creating MFD platform devices the firmware node is left unset.
This, in particular, prevents GPIO library to use it for different
purposes. Propagate firmware node from the parent device and let
GPIO library do the right thing.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2021-12-17 17:50:46 +01:00

214 lines
5.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* gpiolib support for Wolfson Arizona class devices
*
* Copyright 2012 Wolfson Microelectronics PLC.
*
* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/gpio/driver.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/seq_file.h>
#include <linux/mfd/arizona/core.h>
#include <linux/mfd/arizona/pdata.h>
#include <linux/mfd/arizona/registers.h>
struct arizona_gpio {
struct arizona *arizona;
struct gpio_chip gpio_chip;
};
static int arizona_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
{
struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip);
struct arizona *arizona = arizona_gpio->arizona;
bool persistent = gpiochip_line_is_persistent(chip, offset);
bool change;
int ret;
ret = regmap_update_bits_check(arizona->regmap,
ARIZONA_GPIO1_CTRL + offset,
ARIZONA_GPN_DIR, ARIZONA_GPN_DIR,
&change);
if (ret < 0)
return ret;
if (change && persistent) {
pm_runtime_mark_last_busy(chip->parent);
pm_runtime_put_autosuspend(chip->parent);
}
return 0;
}
static int arizona_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip);
struct arizona *arizona = arizona_gpio->arizona;
unsigned int reg, val;
int ret;
reg = ARIZONA_GPIO1_CTRL + offset;
ret = regmap_read(arizona->regmap, reg, &val);
if (ret < 0)
return ret;
/* Resume to read actual registers for input pins */
if (val & ARIZONA_GPN_DIR) {
ret = pm_runtime_get_sync(chip->parent);
if (ret < 0) {
dev_err(chip->parent, "Failed to resume: %d\n", ret);
pm_runtime_put_autosuspend(chip->parent);
return ret;
}
/* Register is cached, drop it to ensure a physical read */
ret = regcache_drop_region(arizona->regmap, reg, reg);
if (ret < 0) {
dev_err(chip->parent, "Failed to drop cache: %d\n",
ret);
pm_runtime_put_autosuspend(chip->parent);
return ret;
}
ret = regmap_read(arizona->regmap, reg, &val);
if (ret < 0) {
pm_runtime_put_autosuspend(chip->parent);
return ret;
}
pm_runtime_mark_last_busy(chip->parent);
pm_runtime_put_autosuspend(chip->parent);
}
if (val & ARIZONA_GPN_LVL)
return 1;
else
return 0;
}
static int arizona_gpio_direction_out(struct gpio_chip *chip,
unsigned offset, int value)
{
struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip);
struct arizona *arizona = arizona_gpio->arizona;
bool persistent = gpiochip_line_is_persistent(chip, offset);
unsigned int val;
int ret;
ret = regmap_read(arizona->regmap, ARIZONA_GPIO1_CTRL + offset, &val);
if (ret < 0)
return ret;
if ((val & ARIZONA_GPN_DIR) && persistent) {
ret = pm_runtime_get_sync(chip->parent);
if (ret < 0) {
dev_err(chip->parent, "Failed to resume: %d\n", ret);
pm_runtime_put(chip->parent);
return ret;
}
}
if (value)
value = ARIZONA_GPN_LVL;
return regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
ARIZONA_GPN_DIR | ARIZONA_GPN_LVL, value);
}
static void arizona_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip);
struct arizona *arizona = arizona_gpio->arizona;
if (value)
value = ARIZONA_GPN_LVL;
regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
ARIZONA_GPN_LVL, value);
}
static const struct gpio_chip template_chip = {
.label = "arizona",
.owner = THIS_MODULE,
.direction_input = arizona_gpio_direction_in,
.get = arizona_gpio_get,
.direction_output = arizona_gpio_direction_out,
.set = arizona_gpio_set,
.can_sleep = true,
};
static int arizona_gpio_probe(struct platform_device *pdev)
{
struct arizona *arizona = dev_get_drvdata(pdev->dev.parent);
struct arizona_pdata *pdata = &arizona->pdata;
struct arizona_gpio *arizona_gpio;
int ret;
device_set_node(&pdev->dev, dev_fwnode(pdev->dev.parent));
arizona_gpio = devm_kzalloc(&pdev->dev, sizeof(*arizona_gpio),
GFP_KERNEL);
if (!arizona_gpio)
return -ENOMEM;
arizona_gpio->arizona = arizona;
arizona_gpio->gpio_chip = template_chip;
arizona_gpio->gpio_chip.parent = &pdev->dev;
switch (arizona->type) {
case WM5102:
case WM5110:
case WM8280:
case WM8997:
case WM8998:
case WM1814:
arizona_gpio->gpio_chip.ngpio = 5;
break;
case WM1831:
case CS47L24:
arizona_gpio->gpio_chip.ngpio = 2;
break;
default:
dev_err(&pdev->dev, "Unknown chip variant %d\n",
arizona->type);
return -EINVAL;
}
if (pdata->gpio_base)
arizona_gpio->gpio_chip.base = pdata->gpio_base;
else
arizona_gpio->gpio_chip.base = -1;
pm_runtime_enable(&pdev->dev);
ret = devm_gpiochip_add_data(&pdev->dev, &arizona_gpio->gpio_chip,
arizona_gpio);
if (ret < 0) {
pm_runtime_disable(&pdev->dev);
dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
ret);
return ret;
}
return 0;
}
static struct platform_driver arizona_gpio_driver = {
.driver.name = "arizona-gpio",
.probe = arizona_gpio_probe,
};
module_platform_driver(arizona_gpio_driver);
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
MODULE_DESCRIPTION("GPIO interface for Arizona devices");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:arizona-gpio");