drivers/gpio/gpio-tps65218.c

   1 /*
   2  * Copyright 2015 Verifone Int.
   3  *
   4  * Author: Nicolas Saenz Julienne <nicolassaenzj@gmail.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify i t
   7  * under  the terms of the GNU General  Public License as published by th e
   8  * Free Software Foundation;  either version 2 of the License, or (at you r
   9  * option) any later version.
  10  *
  11  * This driver is based on the gpio-tps65912 implementation.
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/errno.h>
  17 #include <linux/gpio/driver.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/mfd/tps65218.h>
  20
  21 struct tps65218_gpio {
  22         struct tps65218 *tps65218;
  23         struct gpio_chip gpio_chip;
  24 };
  25
  26 static int tps65218_gpio_get(struct gpio_chip *gc, unsigned offset)
  27 {
  28         struct tps65218_gpio *tps65218_gpio = gpiochip_get_data(gc);
  29         struct tps65218 *tps65218 = tps65218_gpio->tps65218;
  30         unsigned int val;
  31         int ret;
  32
  33         ret = tps65218_reg_read(tps65218, TPS65218_REG_ENABLE2, &val);
  34         if (ret)
  35                 return ret;
  36
  37         return !!(val & (TPS65218_ENABLE2_GPIO1 << offset));
  38 }
  39
  40 static void tps65218_gpio_set(struct gpio_chip *gc, unsigned offset,
  41                               int value)
  42 {
  43         struct tps65218_gpio *tps65218_gpio = gpiochip_get_data(gc);
  44         struct tps65218 *tps65218 = tps65218_gpio->tps65218;
  45
  46         if (value)
  47                 tps65218_set_bits(tps65218, TPS65218_REG_ENABLE2,
  48                                   TPS65218_ENABLE2_GPIO1 << offset,
  49                                   TPS65218_ENABLE2_GPIO1 << offset,
  50                                   TPS65218_PROTECT_L1);
  51         else
  52                 tps65218_clear_bits(tps65218, TPS65218_REG_ENABLE2,
  53                                     TPS65218_ENABLE2_GPIO1 << offset,
  54                                     TPS65218_PROTECT_L1);
  55 }
  56
  57 static int tps65218_gpio_output(struct gpio_chip *gc, unsigned offset,
  58                                 int value)
  59 {
  60         /* Only drives GPOs */
  61         tps65218_gpio_set(gc, offset, value);
  62         return 0;
  63 }
  64
  65 static int tps65218_gpio_input(struct gpio_chip *gc, unsigned offset)
  66 {
  67         return -EPERM;
  68 }
  69
  70 static int tps65218_gpio_request(struct gpio_chip *gc, unsigned offset)
  71 {
  72         struct tps65218_gpio *tps65218_gpio = gpiochip_get_data(gc);
  73         struct tps65218 *tps65218 = tps65218_gpio->tps65218;
  74         int ret;
  75
  76         if (gpiochip_line_is_open_source(gc, offset)) {
  77                 dev_err(gc->parent, "can't work as open source\n");
  78                 return -EINVAL;
  79         }
  80
  81         switch (offset) {
  82         case 0:
  83                 if (!gpiochip_line_is_open_drain(gc, offset)) {
  84                         dev_err(gc->parent, "GPO1 works only as open drain\n");
  85                         return -EINVAL;
  86                 }
  87
  88                 /* Disable sequencer for GPO1 */
  89                 ret = tps65218_clear_bits(tps65218, TPS65218_REG_SEQ7,
  90                                           TPS65218_SEQ7_GPO1_SEQ_MASK,
  91                                           TPS65218_PROTECT_L1);
  92                 if (ret)
  93                         return ret;
  94
  95                 /* Setup GPO1 */
  96                 ret = tps65218_clear_bits(tps65218, TPS65218_REG_CONFIG1,
  97                                           TPS65218_CONFIG1_IO1_SEL,
  98                                           TPS65218_PROTECT_L1);
  99                 if (ret)
 100                         return ret;
 101
 102                 break;
 103         case 1:
 104                 /* GP02 is push-pull by default, can be set as open drain. */
 105                 if (gpiochip_line_is_open_drain(gc, offset)) {
 106                         ret = tps65218_clear_bits(tps65218,
 107                                                   TPS65218_REG_CONFIG1,
 108                                                   TPS65218_CONFIG1_GPO2_BUF,
 109                                                   TPS65218_PROTECT_L1);
 110                         if (ret)
 111                                 return ret;
 112                 }
 113
 114                 /* Setup GPO2 */
 115                 ret = tps65218_clear_bits(tps65218, TPS65218_REG_CONFIG1,
 116                                           TPS65218_CONFIG1_IO1_SEL,
 117                                           TPS65218_PROTECT_L1);
 118                 if (ret)
 119                         return ret;
 120
 121                 break;
 122
 123         case 2:
 124                 if (!gpiochip_line_is_open_drain(gc, offset)) {
 125                         dev_err(gc->parent, "GPO3 works only as open drain\n");
 126                         return -EINVAL;
 127                 }
 128
 129                 /* Disable sequencer for GPO3 */
 130                 ret = tps65218_clear_bits(tps65218, TPS65218_REG_SEQ7,
 131                                           TPS65218_SEQ7_GPO3_SEQ_MASK,
 132                                           TPS65218_PROTECT_L1);
 133                 if (ret)
 134                         return ret;
 135
 136                 /* Setup GPO3 */
 137                 ret = tps65218_clear_bits(tps65218, TPS65218_REG_CONFIG2,
 138                                           TPS65218_CONFIG2_DC12_RST,
 139                                           TPS65218_PROTECT_L1);
 140                 if (ret)
 141                         return ret;
 142
 143                 break;
 144         default:
 145                 return -EINVAL;
 146         }
 147
 148         return 0;
 149 }
 150
 151 static struct gpio_chip template_chip = {
 152         .label                  = "gpio-tps65218",
 153         .owner                  = THIS_MODULE,
 154         .request                = tps65218_gpio_request,
 155         .direction_output       = tps65218_gpio_output,
 156         .direction_input        = tps65218_gpio_input,
 157         .get                    = tps65218_gpio_get,
 158         .set                    = tps65218_gpio_set,
 159         .can_sleep              = true,
 160         .ngpio                  = 3,
 161         .base                   = -1,
 162 };
 163
 164 static int tps65218_gpio_probe(struct platform_device *pdev)
 165 {
 166         struct tps65218 *tps65218 = dev_get_drvdata(pdev->dev.parent);
 167         struct tps65218_gpio *tps65218_gpio;
 168         int ret;
 169
 170         tps65218_gpio = devm_kzalloc(&pdev->dev, sizeof(*tps65218_gpio),
 171                                      GFP_KERNEL);
 172         if (!tps65218_gpio)
 173                 return -ENOMEM;
 174
 175         tps65218_gpio->tps65218 = tps65218;
 176         tps65218_gpio->gpio_chip = template_chip;
 177         tps65218_gpio->gpio_chip.parent = &pdev->dev;
 178 #ifdef CONFIG_OF_GPIO
 179         tps65218_gpio->gpio_chip.of_node = pdev->dev.of_node;
 180 #endif
 181
 182         ret = gpiochip_add_data(&tps65218_gpio->gpio_chip, tps65218_gpio);
 183         if (ret < 0) {
 184                 dev_err(&pdev->dev, "Failed to register gpiochip, %d\n", ret);
 185                 return ret;
 186         }
 187
 188         platform_set_drvdata(pdev, tps65218_gpio);
 189
 190         return ret;
 191 }
 192
 193 static int tps65218_gpio_remove(struct platform_device *pdev)
 194 {
 195         struct tps65218_gpio *tps65218_gpio = platform_get_drvdata(pdev);
 196
 197         gpiochip_remove(&tps65218_gpio->gpio_chip);
 198
 199         return 0;
 200 }
 201
 202 static const struct of_device_id tps65218_dt_match[] = {
 203         { .compatible = "ti,tps65218-gpio" },
 204         {  }
 205 };
 206 MODULE_DEVICE_TABLE(of, tps65218_dt_match);
 207
 208 static struct platform_driver tps65218_gpio_driver = {
 209         .driver = {
 210                 .name = "tps65218-gpio",
 211                 .of_match_table = of_match_ptr(tps65218_dt_match)
 212         },
 213         .probe = tps65218_gpio_probe,
 214         .remove = tps65218_gpio_remove,
 215 };
 216
 217 module_platform_driver(tps65218_gpio_driver);
 218
 219 MODULE_AUTHOR("Nicolas Saenz Julienne <nicolassaenzj@gmail.com>");
 220 MODULE_DESCRIPTION("GPO interface for TPS65218 PMICs");
 221 MODULE_LICENSE("GPL v2");
 222 MODULE_ALIAS("platform:tps65218-gpio");