1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  Copyright Intel Corporation (C) 2014-2016. All Rights Reserved
  4 *
  5 * GPIO driver for  Altera Arria10 MAX5 System Resource Chip
  6 *
  7 * Adapted from gpio-tps65910.c
  8 */
  9
 10#include <linux/gpio/driver.h>
 11#include <linux/mfd/altera-a10sr.h>
 12#include <linux/mod_devicetable.h>
 13#include <linux/module.h>
 14#include <linux/property.h>
 15
 16/**
 17 * struct altr_a10sr_gpio - Altera Max5 GPIO device private data structure
 18 * @gp:   : instance of the gpio_chip
 19 * @regmap: the regmap from the parent device.
 20 */
 21struct altr_a10sr_gpio {
 22	struct gpio_chip gp;
 23	struct regmap *regmap;
 24};
 25
 26static int altr_a10sr_gpio_get(struct gpio_chip *chip, unsigned int offset)
 27{
 28	struct altr_a10sr_gpio *gpio = gpiochip_get_data(chip);
 29	int ret, val;
 30
 31	ret = regmap_read(gpio->regmap, ALTR_A10SR_PBDSW_REG, &val);
 32	if (ret < 0)
 33		return ret;
 34
 35	return !!(val & BIT(offset - ALTR_A10SR_LED_VALID_SHIFT));
 36}
 37
 38static void altr_a10sr_gpio_set(struct gpio_chip *chip, unsigned int offset,
 39				int value)
 40{
 41	struct altr_a10sr_gpio *gpio = gpiochip_get_data(chip);
 42
 43	regmap_update_bits(gpio->regmap, ALTR_A10SR_LED_REG,
 44			   BIT(ALTR_A10SR_LED_VALID_SHIFT + offset),
 45			   value ? BIT(ALTR_A10SR_LED_VALID_SHIFT + offset)
 46			   : 0);
 47}
 48
 49static int altr_a10sr_gpio_direction_input(struct gpio_chip *gc,
 50					   unsigned int nr)
 51{
 52	if (nr < (ALTR_A10SR_IN_VALID_RANGE_LO - ALTR_A10SR_LED_VALID_SHIFT))
 53		return -EINVAL;
 54
 55	return 0;
 56}
 57
 58static int altr_a10sr_gpio_direction_output(struct gpio_chip *gc,
 59					    unsigned int nr, int value)
 60{
 61	if (nr > (ALTR_A10SR_OUT_VALID_RANGE_HI - ALTR_A10SR_LED_VALID_SHIFT))
 62		return -EINVAL;
 63
 64	altr_a10sr_gpio_set(gc, nr, value);
 65	return 0;
 66}
 67
 68static const struct gpio_chip altr_a10sr_gc = {
 69	.label = "altr_a10sr_gpio",
 70	.owner = THIS_MODULE,
 71	.get = altr_a10sr_gpio_get,
 72	.set = altr_a10sr_gpio_set,
 73	.direction_input = altr_a10sr_gpio_direction_input,
 74	.direction_output = altr_a10sr_gpio_direction_output,
 75	.can_sleep = true,
 76	.ngpio = 12,
 77	.base = -1,
 78};
 79
 80static int altr_a10sr_gpio_probe(struct platform_device *pdev)
 81{
 82	struct altr_a10sr_gpio *gpio;
 83	struct altr_a10sr *a10sr = dev_get_drvdata(pdev->dev.parent);
 84
 85	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
 86	if (!gpio)
 87		return -ENOMEM;
 88
 89	gpio->regmap = a10sr->regmap;
 90
 91	gpio->gp = altr_a10sr_gc;
 92	gpio->gp.parent = pdev->dev.parent;
 93	gpio->gp.fwnode = dev_fwnode(&pdev->dev);
 94
 95	return devm_gpiochip_add_data(&pdev->dev, &gpio->gp, gpio);
 96}
 97
 98static const struct of_device_id altr_a10sr_gpio_of_match[] = {
 99	{ .compatible = "altr,a10sr-gpio" },
100	{ },
101};
102MODULE_DEVICE_TABLE(of, altr_a10sr_gpio_of_match);
103
104static struct platform_driver altr_a10sr_gpio_driver = {
105	.probe = altr_a10sr_gpio_probe,
106	.driver = {
107		.name	= "altr_a10sr_gpio",
108		.of_match_table = altr_a10sr_gpio_of_match,
109	},
110};
111module_platform_driver(altr_a10sr_gpio_driver);
112
113MODULE_LICENSE("GPL v2");
114MODULE_AUTHOR("Thor Thayer <tthayer@opensource.altera.com>");
115MODULE_DESCRIPTION("Altera Arria10 System Resource Chip GPIO");