drivers/gpio/gpio-tps68470.c

   1 /*
   2  * GPIO driver for TPS68470 PMIC
   3  *
   4  * Copyright (C) 2017 Intel Corporation
   5  *
   6  * Authors:
   7  *      Antti Laakso <antti.laakso@intel.com>
   8  *      Tianshu Qiu <tian.shu.qiu@intel.com>
   9  *      Jian Xu Zheng <jian.xu.zheng@intel.com>
  10  *      Yuning Pu <yuning.pu@intel.com>
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License as
  14  * published by the Free Software Foundation version 2.
  15  *
  16  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  17  * kind, whether express or implied; without even the implied warranty
  18  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  */
  21
  22 #include <linux/gpio/driver.h>
  23 #include <linux/mfd/tps68470.h>
  24 #include <linux/module.h>
  25 #include <linux/platform_device.h>
  26 #include <linux/regmap.h>
  27
  28 #define TPS68470_N_LOGIC_OUTPUT 3
  29 #define TPS68470_N_REGULAR_GPIO 7
  30 #define TPS68470_N_GPIO (TPS68470_N_LOGIC_OUTPUT + TPS68470_N_REGULAR_GPIO)
  31
  32 struct tps68470_gpio_data {
  33         struct regmap *tps68470_regmap;
  34         struct gpio_chip gc;
  35 };
  36
  37 static int tps68470_gpio_get(struct gpio_chip *gc, unsigned int offset)
  38 {
  39         struct tps68470_gpio_data *tps68470_gpio = gpiochip_get_data(gc);
  40         struct regmap *regmap = tps68470_gpio->tps68470_regmap;
  41         unsigned int reg = TPS68470_REG_GPDO;
  42         int val, ret;
  43
  44         if (offset >= TPS68470_N_REGULAR_GPIO) {
  45                 offset -= TPS68470_N_REGULAR_GPIO;
  46                 reg = TPS68470_REG_SGPO;
  47         }
  48
  49         ret = regmap_read(regmap, reg, &val);
  50         if (ret) {
  51                 dev_err(tps68470_gpio->gc.parent, "reg 0x%x read failed\n",
  52                         TPS68470_REG_SGPO);
  53                 return ret;
  54         }
  55         return !!(val & BIT(offset));
  56 }
  57
  58 /* Return 0 if output, 1 if input */
  59 static int tps68470_gpio_get_direction(struct gpio_chip *gc,
  60                                        unsigned int offset)
  61 {
  62         struct tps68470_gpio_data *tps68470_gpio = gpiochip_get_data(gc);
  63         struct regmap *regmap = tps68470_gpio->tps68470_regmap;
  64         int val, ret;
  65
  66         /* rest are always outputs */
  67         if (offset >= TPS68470_N_REGULAR_GPIO)
  68                 return 0;
  69
  70         ret = regmap_read(regmap, TPS68470_GPIO_CTL_REG_A(offset), &val);
  71         if (ret) {
  72                 dev_err(tps68470_gpio->gc.parent, "reg 0x%x read failed\n",
  73                         TPS68470_GPIO_CTL_REG_A(offset));
  74                 return ret;
  75         }
  76
  77         val &= TPS68470_GPIO_MODE_MASK;
  78         return val >= TPS68470_GPIO_MODE_OUT_CMOS ? 0 : 1;
  79 }
  80
  81 static void tps68470_gpio_set(struct gpio_chip *gc, unsigned int offset,
  82                                 int value)
  83 {
  84         struct tps68470_gpio_data *tps68470_gpio = gpiochip_get_data(gc);
  85         struct regmap *regmap = tps68470_gpio->tps68470_regmap;
  86         unsigned int reg = TPS68470_REG_GPDO;
  87
  88         if (offset >= TPS68470_N_REGULAR_GPIO) {
  89                 reg = TPS68470_REG_SGPO;
  90                 offset -= TPS68470_N_REGULAR_GPIO;
  91         }
  92
  93         regmap_update_bits(regmap, reg, BIT(offset), value ? BIT(offset) : 0);
  94 }
  95
  96 static int tps68470_gpio_output(struct gpio_chip *gc, unsigned int offset,
  97                                 int value)
  98 {
  99         struct tps68470_gpio_data *tps68470_gpio = gpiochip_get_data(gc);
 100         struct regmap *regmap = tps68470_gpio->tps68470_regmap;
 101
 102         /* rest are always outputs */
 103         if (offset >= TPS68470_N_REGULAR_GPIO)
 104                 return 0;
 105
 106         /* Set the initial value */
 107         tps68470_gpio_set(gc, offset, value);
 108
 109         return regmap_update_bits(regmap, TPS68470_GPIO_CTL_REG_A(offset),
 110                                  TPS68470_GPIO_MODE_MASK,
 111                                  TPS68470_GPIO_MODE_OUT_CMOS);
 112 }
 113
 114 static int tps68470_gpio_input(struct gpio_chip *gc, unsigned int offset)
 115 {
 116         struct tps68470_gpio_data *tps68470_gpio = gpiochip_get_data(gc);
 117         struct regmap *regmap = tps68470_gpio->tps68470_regmap;
 118
 119         /* rest are always outputs */
 120         if (offset >= TPS68470_N_REGULAR_GPIO)
 121                 return -EINVAL;
 122
 123         return regmap_update_bits(regmap, TPS68470_GPIO_CTL_REG_A(offset),
 124                                    TPS68470_GPIO_MODE_MASK, 0x00);
 125 }
 126
 127 static const char *tps68470_names[TPS68470_N_GPIO] = {
 128         "gpio.0", "gpio.1", "gpio.2", "gpio.3",
 129         "gpio.4", "gpio.5", "gpio.6",
 130         "s_enable", "s_idle", "s_resetn",
 131 };
 132
 133 static int tps68470_gpio_probe(struct platform_device *pdev)
 134 {
 135         struct tps68470_gpio_data *tps68470_gpio;
 136         int ret;
 137
 138         tps68470_gpio = devm_kzalloc(&pdev->dev, sizeof(*tps68470_gpio),
 139                                      GFP_KERNEL);
 140         if (!tps68470_gpio)
 141                 return -ENOMEM;
 142
 143         tps68470_gpio->tps68470_regmap = dev_get_drvdata(pdev->dev.parent);
 144         tps68470_gpio->gc.label = "tps68470-gpio";
 145         tps68470_gpio->gc.owner = THIS_MODULE;
 146         tps68470_gpio->gc.direction_input = tps68470_gpio_input;
 147         tps68470_gpio->gc.direction_output = tps68470_gpio_output;
 148         tps68470_gpio->gc.get = tps68470_gpio_get;
 149         tps68470_gpio->gc.get_direction = tps68470_gpio_get_direction;
 150         tps68470_gpio->gc.set = tps68470_gpio_set;
 151         tps68470_gpio->gc.can_sleep = true;
 152         tps68470_gpio->gc.names = tps68470_names;
 153         tps68470_gpio->gc.ngpio = TPS68470_N_GPIO;
 154         tps68470_gpio->gc.base = -1;
 155         tps68470_gpio->gc.parent = &pdev->dev;
 156
 157         ret = devm_gpiochip_add_data(&pdev->dev, &tps68470_gpio->gc,
 158                                      tps68470_gpio);
 159         if (ret < 0) {
 160                 dev_err(&pdev->dev, "Failed to register gpio_chip: %d\n", ret);
 161                 return ret;
 162         }
 163
 164         platform_set_drvdata(pdev, tps68470_gpio);
 165
 166         return ret;
 167 }
 168
 169 static struct platform_driver tps68470_gpio_driver = {
 170         .driver = {
 171                    .name = "tps68470-gpio",
 172         },
 173         .probe = tps68470_gpio_probe,
 174 };
 175
 176 builtin_platform_driver(tps68470_gpio_driver)