drivers/gpio/gpio-palmas.c

   1 /*
   2  * TI Palma series PMIC's GPIO driver.
   3  *
   4  * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
   5  *
   6  * Author: Laxman Dewangan <ldewangan@nvidia.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms and conditions of the GNU General Public License,
  10  * version 2, as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  15  * more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <linux/gpio.h>
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/mfd/palmas.h>
  25 #include <linux/of.h>
  26 #include <linux/of_device.h>
  27 #include <linux/platform_device.h>
  28
  29 struct palmas_gpio {
  30         struct gpio_chip gpio_chip;
  31         struct palmas *palmas;
  32 };
  33
  34 static inline struct palmas_gpio *to_palmas_gpio(struct gpio_chip *chip)
  35 {
  36         return container_of(chip, struct palmas_gpio, gpio_chip);
  37 }
  38
  39 static int palmas_gpio_get(struct gpio_chip *gc, unsigned offset)
  40 {
  41         struct palmas_gpio *pg = to_palmas_gpio(gc);
  42         struct palmas *palmas = pg->palmas;
  43         unsigned int val;
  44         int ret;
  45
  46         ret = palmas_read(palmas, PALMAS_GPIO_BASE, PALMAS_GPIO_DATA_DIR, &val);
  47         if (ret < 0) {
  48                 dev_err(gc->dev, "GPIO_DATA_DIR read failed, err = %d\n", ret);
  49                 return ret;
  50         }
  51
  52         if (val & (1 << offset)) {
  53                 ret = palmas_read(palmas, PALMAS_GPIO_BASE,
  54                                   PALMAS_GPIO_DATA_OUT, &val);
  55         } else {
  56                 ret = palmas_read(palmas, PALMAS_GPIO_BASE,
  57                                   PALMAS_GPIO_DATA_IN, &val);
  58         }
  59         if (ret < 0) {
  60                 dev_err(gc->dev, "GPIO_DATA_IN/OUT read failed, err = %d\n",
  61                         ret);
  62                 return ret;
  63         }
  64         return !!(val & BIT(offset));
  65 }
  66
  67 static void palmas_gpio_set(struct gpio_chip *gc, unsigned offset,
  68                         int value)
  69 {
  70         struct palmas_gpio *pg = to_palmas_gpio(gc);
  71         struct palmas *palmas = pg->palmas;
  72         int ret;
  73
  74         if (value)
  75                 ret = palmas_write(palmas, PALMAS_GPIO_BASE,
  76                                 PALMAS_GPIO_SET_DATA_OUT, BIT(offset));
  77         else
  78                 ret = palmas_write(palmas, PALMAS_GPIO_BASE,
  79                                 PALMAS_GPIO_CLEAR_DATA_OUT, BIT(offset));
  80         if (ret < 0)
  81                 dev_err(gc->dev, "%s write failed, err = %d\n",
  82                         (value) ? "GPIO_SET_DATA_OUT" : "GPIO_CLEAR_DATA_OUT",
  83                         ret);
  84 }
  85
  86 static int palmas_gpio_output(struct gpio_chip *gc, unsigned offset,
  87                                 int value)
  88 {
  89         struct palmas_gpio *pg = to_palmas_gpio(gc);
  90         struct palmas *palmas = pg->palmas;
  91         int ret;
  92
  93         /* Set the initial value */
  94         palmas_gpio_set(gc, offset, value);
  95
  96         ret = palmas_update_bits(palmas, PALMAS_GPIO_BASE,
  97                 PALMAS_GPIO_DATA_DIR, BIT(offset), BIT(offset));
  98         if (ret < 0)
  99                 dev_err(gc->dev, "GPIO_DATA_DIR write failed, err = %d\n", ret);
 100         return ret;
 101 }
 102
 103 static int palmas_gpio_input(struct gpio_chip *gc, unsigned offset)
 104 {
 105         struct palmas_gpio *pg = to_palmas_gpio(gc);
 106         struct palmas *palmas = pg->palmas;
 107         int ret;
 108
 109         ret = palmas_update_bits(palmas, PALMAS_GPIO_BASE,
 110                 PALMAS_GPIO_DATA_DIR, BIT(offset), 0);
 111         if (ret < 0)
 112                 dev_err(gc->dev, "GPIO_DATA_DIR write failed, err = %d\n", ret);
 113         return ret;
 114 }
 115
 116 static int palmas_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
 117 {
 118         struct palmas_gpio *pg = to_palmas_gpio(gc);
 119         struct palmas *palmas = pg->palmas;
 120
 121         return palmas_irq_get_virq(palmas, PALMAS_GPIO_0_IRQ + offset);
 122 }
 123
 124 static int palmas_gpio_probe(struct platform_device *pdev)
 125 {
 126         struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
 127         struct palmas_platform_data *palmas_pdata;
 128         struct palmas_gpio *palmas_gpio;
 129         int ret;
 130
 131         palmas_gpio = devm_kzalloc(&pdev->dev,
 132                                 sizeof(*palmas_gpio), GFP_KERNEL);
 133         if (!palmas_gpio) {
 134                 dev_err(&pdev->dev, "Could not allocate palmas_gpio\n");
 135                 return -ENOMEM;
 136         }
 137
 138         palmas_gpio->palmas = palmas;
 139         palmas_gpio->gpio_chip.owner = THIS_MODULE;
 140         palmas_gpio->gpio_chip.label = dev_name(&pdev->dev);
 141         palmas_gpio->gpio_chip.ngpio = 8;
 142         palmas_gpio->gpio_chip.can_sleep = 1;
 143         palmas_gpio->gpio_chip.direction_input = palmas_gpio_input;
 144         palmas_gpio->gpio_chip.direction_output = palmas_gpio_output;
 145         palmas_gpio->gpio_chip.to_irq = palmas_gpio_to_irq;
 146         palmas_gpio->gpio_chip.set      = palmas_gpio_set;
 147         palmas_gpio->gpio_chip.get      = palmas_gpio_get;
 148         palmas_gpio->gpio_chip.dev = &pdev->dev;
 149 #ifdef CONFIG_OF_GPIO
 150         palmas_gpio->gpio_chip.of_node = pdev->dev.of_node;
 151 #endif
 152         palmas_pdata = dev_get_platdata(palmas->dev);
 153         if (palmas_pdata && palmas_pdata->gpio_base)
 154                 palmas_gpio->gpio_chip.base = palmas_pdata->gpio_base;
 155         else
 156                 palmas_gpio->gpio_chip.base = -1;
 157
 158         ret = gpiochip_add(&palmas_gpio->gpio_chip);
 159         if (ret < 0) {
 160                 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
 161                 return ret;
 162         }
 163
 164         platform_set_drvdata(pdev, palmas_gpio);
 165         return ret;
 166 }
 167
 168 static int palmas_gpio_remove(struct platform_device *pdev)
 169 {
 170         struct palmas_gpio *palmas_gpio = platform_get_drvdata(pdev);
 171
 172         return gpiochip_remove(&palmas_gpio->gpio_chip);
 173 }
 174
 175 static struct of_device_id of_palmas_gpio_match[] = {
 176         { .compatible = "ti,palmas-gpio"},
 177         { .compatible = "ti,tps65913-gpio"},
 178         { .compatible = "ti,tps65914-gpio"},
 179         { .compatible = "ti,tps80036-gpio"},
 180         { },
 181 };
 182 MODULE_DEVICE_TABLE(of, of_palmas_gpio_match);
 183
 184 static struct platform_driver palmas_gpio_driver = {
 185         .driver.name    = "palmas-gpio",
 186         .driver.owner   = THIS_MODULE,
 187         .driver.of_match_table = of_palmas_gpio_match,
 188         .probe          = palmas_gpio_probe,
 189         .remove         = palmas_gpio_remove,
 190 };
 191
 192 static int __init palmas_gpio_init(void)
 193 {
 194         return platform_driver_register(&palmas_gpio_driver);
 195 }
 196 subsys_initcall(palmas_gpio_init);
 197
 198 static void __exit palmas_gpio_exit(void)
 199 {
 200         platform_driver_unregister(&palmas_gpio_driver);
 201 }
 202 module_exit(palmas_gpio_exit);
 203
 204 MODULE_ALIAS("platform:palmas-gpio");
 205 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
 206 MODULE_DESCRIPTION("GPIO driver for TI Palmas series PMICs");
 207 MODULE_LICENSE("GPL v2");