LXR linux/drivers/gpio/gpio-altera-a10sr.c

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