drivers/gpio/gpio-max77650.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 //
   3 // Copyright (C) 2018 BayLibre SAS
   4 // Author: Bartosz Golaszewski <bgolaszewski@baylibre.com>
   5 //
   6 // GPIO driver for MAXIM 77650/77651 charger/power-supply.
   7
   8 #include <linux/gpio/driver.h>
   9 #include <linux/i2c.h>
  10 #include <linux/mfd/max77650.h>
  11 #include <linux/module.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/regmap.h>
  14
  15 #define MAX77650_GPIO_DIR_MASK          BIT(0)
  16 #define MAX77650_GPIO_INVAL_MASK        BIT(1)
  17 #define MAX77650_GPIO_DRV_MASK          BIT(2)
  18 #define MAX77650_GPIO_OUTVAL_MASK       BIT(3)
  19 #define MAX77650_GPIO_DEBOUNCE_MASK     BIT(4)
  20
  21 #define MAX77650_GPIO_DIR_OUT           0x00
  22 #define MAX77650_GPIO_DIR_IN            BIT(0)
  23 #define MAX77650_GPIO_OUT_LOW           0x00
  24 #define MAX77650_GPIO_OUT_HIGH          BIT(3)
  25 #define MAX77650_GPIO_DRV_OPEN_DRAIN    0x00
  26 #define MAX77650_GPIO_DRV_PUSH_PULL     BIT(2)
  27 #define MAX77650_GPIO_DEBOUNCE          BIT(4)
  28
  29 #define MAX77650_GPIO_DIR_BITS(_reg) \
  30                 ((_reg) & MAX77650_GPIO_DIR_MASK)
  31 #define MAX77650_GPIO_INVAL_BITS(_reg) \
  32                 (((_reg) & MAX77650_GPIO_INVAL_MASK) >> 1)
  33
  34 struct max77650_gpio_chip {
  35         struct regmap *map;
  36         struct gpio_chip gc;
  37         int irq;
  38 };
  39
  40 static int max77650_gpio_direction_input(struct gpio_chip *gc,
  41                                          unsigned int offset)
  42 {
  43         struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
  44
  45         return regmap_update_bits(chip->map,
  46                                   MAX77650_REG_CNFG_GPIO,
  47                                   MAX77650_GPIO_DIR_MASK,
  48                                   MAX77650_GPIO_DIR_IN);
  49 }
  50
  51 static int max77650_gpio_direction_output(struct gpio_chip *gc,
  52                                           unsigned int offset, int value)
  53 {
  54         struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
  55         int mask, regval;
  56
  57         mask = MAX77650_GPIO_DIR_MASK | MAX77650_GPIO_OUTVAL_MASK;
  58         regval = value ? MAX77650_GPIO_OUT_HIGH : MAX77650_GPIO_OUT_LOW;
  59         regval |= MAX77650_GPIO_DIR_OUT;
  60
  61         return regmap_update_bits(chip->map,
  62                                   MAX77650_REG_CNFG_GPIO, mask, regval);
  63 }
  64
  65 static void max77650_gpio_set_value(struct gpio_chip *gc,
  66                                     unsigned int offset, int value)
  67 {
  68         struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
  69         int rv, regval;
  70
  71         regval = value ? MAX77650_GPIO_OUT_HIGH : MAX77650_GPIO_OUT_LOW;
  72
  73         rv = regmap_update_bits(chip->map, MAX77650_REG_CNFG_GPIO,
  74                                 MAX77650_GPIO_OUTVAL_MASK, regval);
  75         if (rv)
  76                 dev_err(gc->parent, "cannot set GPIO value: %d\n", rv);
  77 }
  78
  79 static int max77650_gpio_get_value(struct gpio_chip *gc,
  80                                    unsigned int offset)
  81 {
  82         struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
  83         unsigned int val;
  84         int rv;
  85
  86         rv = regmap_read(chip->map, MAX77650_REG_CNFG_GPIO, &val);
  87         if (rv)
  88                 return rv;
  89
  90         return MAX77650_GPIO_INVAL_BITS(val);
  91 }
  92
  93 static int max77650_gpio_get_direction(struct gpio_chip *gc,
  94                                        unsigned int offset)
  95 {
  96         struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
  97         unsigned int val;
  98         int rv;
  99
 100         rv = regmap_read(chip->map, MAX77650_REG_CNFG_GPIO, &val);
 101         if (rv)
 102                 return rv;
 103
 104         return MAX77650_GPIO_DIR_BITS(val);
 105 }
 106
 107 static int max77650_gpio_set_config(struct gpio_chip *gc,
 108                                     unsigned int offset, unsigned long cfg)
 109 {
 110         struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
 111
 112         switch (pinconf_to_config_param(cfg)) {
 113         case PIN_CONFIG_DRIVE_OPEN_DRAIN:
 114                 return regmap_update_bits(chip->map,
 115                                           MAX77650_REG_CNFG_GPIO,
 116                                           MAX77650_GPIO_DRV_MASK,
 117                                           MAX77650_GPIO_DRV_OPEN_DRAIN);
 118         case PIN_CONFIG_DRIVE_PUSH_PULL:
 119                 return regmap_update_bits(chip->map,
 120                                           MAX77650_REG_CNFG_GPIO,
 121                                           MAX77650_GPIO_DRV_MASK,
 122                                           MAX77650_GPIO_DRV_PUSH_PULL);
 123         case PIN_CONFIG_INPUT_DEBOUNCE:
 124                 return regmap_update_bits(chip->map,
 125                                           MAX77650_REG_CNFG_GPIO,
 126                                           MAX77650_GPIO_DEBOUNCE_MASK,
 127                                           MAX77650_GPIO_DEBOUNCE);
 128         default:
 129                 return -ENOTSUPP;
 130         }
 131 }
 132
 133 static int max77650_gpio_to_irq(struct gpio_chip *gc, unsigned int offset)
 134 {
 135         struct max77650_gpio_chip *chip = gpiochip_get_data(gc);
 136
 137         return chip->irq;
 138 }
 139
 140 static int max77650_gpio_probe(struct platform_device *pdev)
 141 {
 142         struct max77650_gpio_chip *chip;
 143         struct device *dev, *parent;
 144         struct i2c_client *i2c;
 145
 146         dev = &pdev->dev;
 147         parent = dev->parent;
 148         i2c = to_i2c_client(parent);
 149
 150         chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
 151         if (!chip)
 152                 return -ENOMEM;
 153
 154         chip->map = dev_get_regmap(parent, NULL);
 155         if (!chip->map)
 156                 return -ENODEV;
 157
 158         chip->irq = platform_get_irq_byname(pdev, "GPI");
 159         if (chip->irq < 0)
 160                 return chip->irq;
 161
 162         chip->gc.base = -1;
 163         chip->gc.ngpio = 1;
 164         chip->gc.label = i2c->name;
 165         chip->gc.parent = dev;
 166         chip->gc.owner = THIS_MODULE;
 167         chip->gc.can_sleep = true;
 168
 169         chip->gc.direction_input = max77650_gpio_direction_input;
 170         chip->gc.direction_output = max77650_gpio_direction_output;
 171         chip->gc.set = max77650_gpio_set_value;
 172         chip->gc.get = max77650_gpio_get_value;
 173         chip->gc.get_direction = max77650_gpio_get_direction;
 174         chip->gc.set_config = max77650_gpio_set_config;
 175         chip->gc.to_irq = max77650_gpio_to_irq;
 176
 177         return devm_gpiochip_add_data(dev, &chip->gc, chip);
 178 }
 179
 180 static struct platform_driver max77650_gpio_driver = {
 181         .driver = {
 182                 .name = "max77650-gpio",
 183         },
 184         .probe = max77650_gpio_probe,
 185 };
 186 module_platform_driver(max77650_gpio_driver);
 187
 188 MODULE_DESCRIPTION("MAXIM 77650/77651 GPIO driver");
 189 MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>");
 190 MODULE_LICENSE("GPL v2");
 191 MODULE_ALIAS("platform:max77650-gpio");