gpio-wm8350.c

  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * gpiolib support for Wolfson WM835x PMICs
  4 *
  5 * Copyright 2009 Wolfson Microelectronics PLC.
  6 *
  7 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
  8 *
  9 */
 10
 11#include <linux/gpio/driver.h>
 12#include <linux/kernel.h>
 13#include <linux/mfd/core.h>
 14#include <linux/module.h>
 15#include <linux/platform_device.h>
 16#include <linux/slab.h>
 17
 18#include <linux/mfd/wm8350/core.h>
 19#include <linux/mfd/wm8350/gpio.h>
 20
 21struct wm8350_gpio_data {
 22	struct wm8350 *wm8350;
 23	struct gpio_chip gpio_chip;
 24};
 25
 26static int wm8350_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
 27{
 28	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
 29	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
 30
 31	return wm8350_set_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
 32			       1 << offset);
 33}
 34
 35static int wm8350_gpio_get(struct gpio_chip *chip, unsigned offset)
 36{
 37	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
 38	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
 39	int ret;
 40
 41	ret = wm8350_reg_read(wm8350, WM8350_GPIO_LEVEL);
 42	if (ret < 0)
 43		return ret;
 44
 45	if (ret & (1 << offset))
 46		return 1;
 47	else
 48		return 0;
 49}
 50
 51static int wm8350_gpio_set(struct gpio_chip *chip, unsigned int offset,
 52			   int value)
 53{
 54	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
 55	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
 56
 57	if (value)
 58		return wm8350_set_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
 59
 60	return wm8350_clear_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
 61}
 62
 63static int wm8350_gpio_direction_out(struct gpio_chip *chip,
 64				     unsigned offset, int value)
 65{
 66	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
 67	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
 68	int ret;
 69
 70	ret = wm8350_clear_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
 71				1 << offset);
 72	if (ret < 0)
 73		return ret;
 74
 75	/* Don't have an atomic direction/value setup */
 76	return wm8350_gpio_set(chip, offset, value);
 77}
 78
 79static int wm8350_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 80{
 81	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
 82	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
 83
 84	if (!wm8350->irq_base)
 85		return -EINVAL;
 86
 87	return wm8350->irq_base + WM8350_IRQ_GPIO(offset);
 88}
 89
 90static const struct gpio_chip template_chip = {
 91	.label			= "wm8350",
 92	.owner			= THIS_MODULE,
 93	.direction_input	= wm8350_gpio_direction_in,
 94	.get			= wm8350_gpio_get,
 95	.direction_output	= wm8350_gpio_direction_out,
 96	.set			= wm8350_gpio_set,
 97	.to_irq			= wm8350_gpio_to_irq,
 98	.can_sleep		= true,
 99};
100
101static int wm8350_gpio_probe(struct platform_device *pdev)
102{
103	struct wm8350 *wm8350 = dev_get_drvdata(pdev->dev.parent);
104	struct wm8350_platform_data *pdata = dev_get_platdata(wm8350->dev);
105	struct wm8350_gpio_data *wm8350_gpio;
106
107	wm8350_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8350_gpio),
108				   GFP_KERNEL);
109	if (wm8350_gpio == NULL)
110		return -ENOMEM;
111
112	wm8350_gpio->wm8350 = wm8350;
113	wm8350_gpio->gpio_chip = template_chip;
114	wm8350_gpio->gpio_chip.ngpio = 13;
115	wm8350_gpio->gpio_chip.parent = &pdev->dev;
116	if (pdata && pdata->gpio_base)
117		wm8350_gpio->gpio_chip.base = pdata->gpio_base;
118	else
119		wm8350_gpio->gpio_chip.base = -1;
120
121	return devm_gpiochip_add_data(&pdev->dev, &wm8350_gpio->gpio_chip, wm8350_gpio);
122}
123
124static struct platform_driver wm8350_gpio_driver = {
125	.driver.name	= "wm8350-gpio",
126	.probe		= wm8350_gpio_probe,
127};
128
129static int __init wm8350_gpio_init(void)
130{
131	return platform_driver_register(&wm8350_gpio_driver);
132}
133subsys_initcall(wm8350_gpio_init);
134
135static void __exit wm8350_gpio_exit(void)
136{
137	platform_driver_unregister(&wm8350_gpio_driver);
138}
139module_exit(wm8350_gpio_exit);
140
141MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
142MODULE_DESCRIPTION("GPIO interface for WM8350 PMICs");
143MODULE_LICENSE("GPL");
144MODULE_ALIAS("platform:wm8350-gpio");