drivers/gpio/gpio-wcd934x.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (c) 2019, Linaro Limited
   3
   4 #include <linux/mod_devicetable.h>
   5 #include <linux/module.h>
   6 #include <linux/gpio/driver.h>
   7 #include <linux/platform_device.h>
   8 #include <linux/regmap.h>
   9 #include <linux/slab.h>
  10
  11 #define WCD_PIN_MASK(p) BIT(p)
  12 #define WCD_REG_DIR_CTL_OFFSET 0x42
  13 #define WCD_REG_VAL_CTL_OFFSET 0x43
  14 #define WCD934X_NPINS           5
  15
  16 struct wcd_gpio_data {
  17         struct regmap *map;
  18         struct gpio_chip chip;
  19 };
  20
  21 static int wcd_gpio_get_direction(struct gpio_chip *chip, unsigned int pin)
  22 {
  23         struct wcd_gpio_data *data = gpiochip_get_data(chip);
  24         unsigned int value;
  25         int ret;
  26
  27         ret = regmap_read(data->map, WCD_REG_DIR_CTL_OFFSET, &value);
  28         if (ret < 0)
  29                 return ret;
  30
  31         if (value & WCD_PIN_MASK(pin))
  32                 return GPIO_LINE_DIRECTION_OUT;
  33
  34         return GPIO_LINE_DIRECTION_IN;
  35 }
  36
  37 static int wcd_gpio_direction_input(struct gpio_chip *chip, unsigned int pin)
  38 {
  39         struct wcd_gpio_data *data = gpiochip_get_data(chip);
  40
  41         return regmap_update_bits(data->map, WCD_REG_DIR_CTL_OFFSET,
  42                                   WCD_PIN_MASK(pin), 0);
  43 }
  44
  45 static int wcd_gpio_direction_output(struct gpio_chip *chip, unsigned int pin,
  46                                      int val)
  47 {
  48         struct wcd_gpio_data *data = gpiochip_get_data(chip);
  49
  50         regmap_update_bits(data->map, WCD_REG_DIR_CTL_OFFSET,
  51                            WCD_PIN_MASK(pin), WCD_PIN_MASK(pin));
  52
  53         return regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET,
  54                                   WCD_PIN_MASK(pin),
  55                                   val ? WCD_PIN_MASK(pin) : 0);
  56 }
  57
  58 static int wcd_gpio_get(struct gpio_chip *chip, unsigned int pin)
  59 {
  60         struct wcd_gpio_data *data = gpiochip_get_data(chip);
  61         unsigned int value;
  62
  63         regmap_read(data->map, WCD_REG_VAL_CTL_OFFSET, &value);
  64
  65         return !!(value & WCD_PIN_MASK(pin));
  66 }
  67
  68 static void wcd_gpio_set(struct gpio_chip *chip, unsigned int pin, int val)
  69 {
  70         struct wcd_gpio_data *data = gpiochip_get_data(chip);
  71
  72         regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET,
  73                            WCD_PIN_MASK(pin), val ? WCD_PIN_MASK(pin) : 0);
  74 }
  75
  76 static int wcd_gpio_probe(struct platform_device *pdev)
  77 {
  78         struct device *dev = &pdev->dev;
  79         struct wcd_gpio_data *data;
  80         struct gpio_chip *chip;
  81
  82         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
  83         if (!data)
  84                 return -ENOMEM;
  85
  86         data->map = dev_get_regmap(dev->parent, NULL);
  87         if (!data->map) {
  88                 dev_err(dev, "%s: failed to get regmap\n", __func__);
  89                 return  -EINVAL;
  90         }
  91
  92         chip = &data->chip;
  93         chip->direction_input  = wcd_gpio_direction_input;
  94         chip->direction_output = wcd_gpio_direction_output;
  95         chip->get_direction = wcd_gpio_get_direction;
  96         chip->get = wcd_gpio_get;
  97         chip->set = wcd_gpio_set;
  98         chip->parent = dev;
  99         chip->base = -1;
 100         chip->ngpio = WCD934X_NPINS;
 101         chip->label = dev_name(dev);
 102         chip->can_sleep = false;
 103
 104         return devm_gpiochip_add_data(dev, chip, data);
 105 }
 106
 107 static const struct of_device_id wcd_gpio_of_match[] = {
 108         { .compatible = "qcom,wcd9340-gpio" },
 109         { .compatible = "qcom,wcd9341-gpio" },
 110         { }
 111 };
 112 MODULE_DEVICE_TABLE(of, wcd_gpio_of_match);
 113
 114 static struct platform_driver wcd_gpio_driver = {
 115         .driver = {
 116                    .name = "wcd934x-gpio",
 117                    .of_match_table = wcd_gpio_of_match,
 118         },
 119         .probe = wcd_gpio_probe,
 120 };
 121
 122 module_platform_driver(wcd_gpio_driver);
 123 MODULE_DESCRIPTION("Qualcomm Technologies, Inc WCD GPIO control driver");
 124 MODULE_LICENSE("GPL v2");