drivers/gpio/gpio-lp87565.c

   1 /*
   2  * Copyright (C) 2017 Texas Instruments Incorporated - http://www.ti.com/
   3  *      Keerthy <j-keerthy@ti.com>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  10  * kind, whether expressed or implied; without even the implied warranty
  11  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License version 2 for more details.
  13  *
  14  * Based on the LP873X driver
  15  */
  16
  17 #include <linux/gpio/driver.h>
  18 #include <linux/module.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/regmap.h>
  21
  22 #include <linux/mfd/lp87565.h>
  23
  24 struct lp87565_gpio {
  25         struct gpio_chip chip;
  26         struct regmap *map;
  27 };
  28
  29 static int lp87565_gpio_get(struct gpio_chip *chip, unsigned int offset)
  30 {
  31         struct lp87565_gpio *gpio = gpiochip_get_data(chip);
  32         int ret, val;
  33
  34         ret = regmap_read(gpio->map, LP87565_REG_GPIO_IN, &val);
  35         if (ret < 0)
  36                 return ret;
  37
  38         return !!(val & BIT(offset));
  39 }
  40
  41 static void lp87565_gpio_set(struct gpio_chip *chip, unsigned int offset,
  42                              int value)
  43 {
  44         struct lp87565_gpio *gpio = gpiochip_get_data(chip);
  45
  46         regmap_update_bits(gpio->map, LP87565_REG_GPIO_OUT,
  47                            BIT(offset), value ? BIT(offset) : 0);
  48 }
  49
  50 static int lp87565_gpio_get_direction(struct gpio_chip *chip,
  51                                       unsigned int offset)
  52 {
  53         struct lp87565_gpio *gpio = gpiochip_get_data(chip);
  54         int ret, val;
  55
  56         ret = regmap_read(gpio->map, LP87565_REG_GPIO_CONFIG, &val);
  57         if (ret < 0)
  58                 return ret;
  59
  60         if (val & BIT(offset))
  61                 return GPIO_LINE_DIRECTION_OUT;
  62
  63         return GPIO_LINE_DIRECTION_IN;
  64 }
  65
  66 static int lp87565_gpio_direction_input(struct gpio_chip *chip,
  67                                         unsigned int offset)
  68 {
  69         struct lp87565_gpio *gpio = gpiochip_get_data(chip);
  70
  71         return regmap_update_bits(gpio->map,
  72                                   LP87565_REG_GPIO_CONFIG,
  73                                   BIT(offset), 0);
  74 }
  75
  76 static int lp87565_gpio_direction_output(struct gpio_chip *chip,
  77                                          unsigned int offset, int value)
  78 {
  79         struct lp87565_gpio *gpio = gpiochip_get_data(chip);
  80
  81         lp87565_gpio_set(chip, offset, value);
  82
  83         return regmap_update_bits(gpio->map,
  84                                   LP87565_REG_GPIO_CONFIG,
  85                                   BIT(offset), BIT(offset));
  86 }
  87
  88 static int lp87565_gpio_request(struct gpio_chip *gc, unsigned int offset)
  89 {
  90         struct lp87565_gpio *gpio = gpiochip_get_data(gc);
  91         int ret;
  92
  93         switch (offset) {
  94         case 0:
  95         case 1:
  96         case 2:
  97                 /*
  98                  * MUX can program the pin to be in EN1/2/3 pin mode
  99                  * Or GPIO1/2/3 mode.
 100                  * Setup the GPIO*_SEL MUX to GPIO mode
 101                  */
 102                 ret = regmap_update_bits(gpio->map,
 103                                          LP87565_REG_PIN_FUNCTION,
 104                                          BIT(offset), BIT(offset));
 105                 if (ret)
 106                         return ret;
 107
 108                 break;
 109         default:
 110                 return -EINVAL;
 111         }
 112
 113         return 0;
 114 }
 115
 116 static int lp87565_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
 117                                    unsigned long config)
 118 {
 119         struct lp87565_gpio *gpio = gpiochip_get_data(gc);
 120
 121         switch (pinconf_to_config_param(config)) {
 122         case PIN_CONFIG_DRIVE_OPEN_DRAIN:
 123                 return regmap_update_bits(gpio->map,
 124                                           LP87565_REG_GPIO_CONFIG,
 125                                           BIT(offset +
 126                                               __ffs(LP87565_GOIO1_OD)),
 127                                           BIT(offset +
 128                                               __ffs(LP87565_GOIO1_OD)));
 129         case PIN_CONFIG_DRIVE_PUSH_PULL:
 130                 return regmap_update_bits(gpio->map,
 131                                           LP87565_REG_GPIO_CONFIG,
 132                                           BIT(offset +
 133                                               __ffs(LP87565_GOIO1_OD)), 0);
 134         default:
 135                 return -ENOTSUPP;
 136         }
 137 }
 138
 139 static const struct gpio_chip template_chip = {
 140         .label                  = "lp87565-gpio",
 141         .owner                  = THIS_MODULE,
 142         .request                = lp87565_gpio_request,
 143         .get_direction          = lp87565_gpio_get_direction,
 144         .direction_input        = lp87565_gpio_direction_input,
 145         .direction_output       = lp87565_gpio_direction_output,
 146         .get                    = lp87565_gpio_get,
 147         .set                    = lp87565_gpio_set,
 148         .set_config             = lp87565_gpio_set_config,
 149         .base                   = -1,
 150         .ngpio                  = 3,
 151         .can_sleep              = true,
 152 };
 153
 154 static int lp87565_gpio_probe(struct platform_device *pdev)
 155 {
 156         struct lp87565_gpio *gpio;
 157         struct lp87565 *lp87565;
 158         int ret;
 159
 160         gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
 161         if (!gpio)
 162                 return -ENOMEM;
 163
 164         lp87565 = dev_get_drvdata(pdev->dev.parent);
 165         gpio->chip = template_chip;
 166         gpio->chip.parent = lp87565->dev;
 167         gpio->map = lp87565->regmap;
 168
 169         ret = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
 170         if (ret < 0) {
 171                 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
 172                 return ret;
 173         }
 174
 175         return 0;
 176 }
 177
 178 static const struct platform_device_id lp87565_gpio_id_table[] = {
 179         { "lp87565-q1-gpio", },
 180         { /* sentinel */ }
 181 };
 182 MODULE_DEVICE_TABLE(platform, lp87565_gpio_id_table);
 183
 184 static struct platform_driver lp87565_gpio_driver = {
 185         .driver = {
 186                 .name = "lp87565-gpio",
 187         },
 188         .probe = lp87565_gpio_probe,
 189         .id_table = lp87565_gpio_id_table,
 190 };
 191 module_platform_driver(lp87565_gpio_driver);
 192
 193 MODULE_AUTHOR("Keerthy <j-keerthy@ti.com>");
 194 MODULE_DESCRIPTION("LP87565 GPIO driver");
 195 MODULE_LICENSE("GPL v2");