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