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 struct palmas_device_data {
  35         int ngpio;
  36 };
  37
  38 static int palmas_gpio_get(struct gpio_chip *gc, unsigned offset)
  39 {
  40         struct palmas_gpio *pg = gpiochip_get_data(gc);
  41         struct palmas *palmas = pg->palmas;
  42         unsigned int val;
  43         int ret;
  44         unsigned int reg;
  45         int gpio16 = (offset/8);
  46
  47         offset %= 8;
  48         reg = (gpio16) ? PALMAS_GPIO_DATA_DIR2 : PALMAS_GPIO_DATA_DIR;
  49
  50         ret = palmas_read(palmas, PALMAS_GPIO_BASE, reg, &val);
  51         if (ret < 0) {
  52                 dev_err(gc->parent, "Reg 0x%02x read failed, %d\n", reg, ret);
  53                 return ret;
  54         }
  55
  56         if (val & BIT(offset))
  57                 reg = (gpio16) ? PALMAS_GPIO_DATA_OUT2 : PALMAS_GPIO_DATA_OUT;
  58         else
  59                 reg = (gpio16) ? PALMAS_GPIO_DATA_IN2 : PALMAS_GPIO_DATA_IN;
  60
  61         ret = palmas_read(palmas, PALMAS_GPIO_BASE, reg, &val);
  62         if (ret < 0) {
  63                 dev_err(gc->parent, "Reg 0x%02x read failed, %d\n", reg, ret);
  64                 return ret;
  65         }
  66         return !!(val & BIT(offset));
  67 }
  68
  69 static void palmas_gpio_set(struct gpio_chip *gc, unsigned offset,
  70                         int value)
  71 {
  72         struct palmas_gpio *pg = gpiochip_get_data(gc);
  73         struct palmas *palmas = pg->palmas;
  74         int ret;
  75         unsigned int reg;
  76         int gpio16 = (offset/8);
  77
  78         offset %= 8;
  79         if (gpio16)
  80                 reg = (value) ?
  81                         PALMAS_GPIO_SET_DATA_OUT2 : PALMAS_GPIO_CLEAR_DATA_OUT2;
  82         else
  83                 reg = (value) ?
  84                         PALMAS_GPIO_SET_DATA_OUT : PALMAS_GPIO_CLEAR_DATA_OUT;
  85
  86         ret = palmas_write(palmas, PALMAS_GPIO_BASE, reg, BIT(offset));
  87         if (ret < 0)
  88                 dev_err(gc->parent, "Reg 0x%02x write failed, %d\n", reg, ret);
  89 }
  90
  91 static int palmas_gpio_output(struct gpio_chip *gc, unsigned offset,
  92                                 int value)
  93 {
  94         struct palmas_gpio *pg = gpiochip_get_data(gc);
  95         struct palmas *palmas = pg->palmas;
  96         int ret;
  97         unsigned int reg;
  98         int gpio16 = (offset/8);
  99
 100         offset %= 8;
 101         reg = (gpio16) ? PALMAS_GPIO_DATA_DIR2 : PALMAS_GPIO_DATA_DIR;
 102
 103         /* Set the initial value */
 104         palmas_gpio_set(gc, offset, value);
 105
 106         ret = palmas_update_bits(palmas, PALMAS_GPIO_BASE, reg,
 107                                 BIT(offset), BIT(offset));
 108         if (ret < 0)
 109                 dev_err(gc->parent, "Reg 0x%02x update failed, %d\n", reg,
 110                         ret);
 111         return ret;
 112 }
 113
 114 static int palmas_gpio_input(struct gpio_chip *gc, unsigned offset)
 115 {
 116         struct palmas_gpio *pg = gpiochip_get_data(gc);
 117         struct palmas *palmas = pg->palmas;
 118         int ret;
 119         unsigned int reg;
 120         int gpio16 = (offset/8);
 121
 122         offset %= 8;
 123         reg = (gpio16) ? PALMAS_GPIO_DATA_DIR2 : PALMAS_GPIO_DATA_DIR;
 124
 125         ret = palmas_update_bits(palmas, PALMAS_GPIO_BASE, reg, BIT(offset), 0);
 126         if (ret < 0)
 127                 dev_err(gc->parent, "Reg 0x%02x update failed, %d\n", reg,
 128                         ret);
 129         return ret;
 130 }
 131
 132 static int palmas_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
 133 {
 134         struct palmas_gpio *pg = gpiochip_get_data(gc);
 135         struct palmas *palmas = pg->palmas;
 136
 137         return palmas_irq_get_virq(palmas, PALMAS_GPIO_0_IRQ + offset);
 138 }
 139
 140 static const struct palmas_device_data palmas_dev_data = {
 141         .ngpio = 8,
 142 };
 143
 144 static const struct palmas_device_data tps80036_dev_data = {
 145         .ngpio = 16,
 146 };
 147
 148 static const struct of_device_id of_palmas_gpio_match[] = {
 149         { .compatible = "ti,palmas-gpio", .data = &palmas_dev_data,},
 150         { .compatible = "ti,tps65913-gpio", .data = &palmas_dev_data,},
 151         { .compatible = "ti,tps65914-gpio", .data = &palmas_dev_data,},
 152         { .compatible = "ti,tps80036-gpio", .data = &tps80036_dev_data,},
 153         { },
 154 };
 155 MODULE_DEVICE_TABLE(of, of_palmas_gpio_match);
 156
 157 static int palmas_gpio_probe(struct platform_device *pdev)
 158 {
 159         struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
 160         struct palmas_platform_data *palmas_pdata;
 161         struct palmas_gpio *palmas_gpio;
 162         int ret;
 163         const struct of_device_id *match;
 164         const struct palmas_device_data *dev_data;
 165
 166         match = of_match_device(of_palmas_gpio_match, &pdev->dev);
 167         if (!match)
 168                 return -ENODEV;
 169         dev_data = match->data;
 170         if (!dev_data)
 171                 dev_data = &palmas_dev_data;
 172
 173         palmas_gpio = devm_kzalloc(&pdev->dev,
 174                                 sizeof(*palmas_gpio), GFP_KERNEL);
 175         if (!palmas_gpio)
 176                 return -ENOMEM;
 177
 178         palmas_gpio->palmas = palmas;
 179         palmas_gpio->gpio_chip.owner = THIS_MODULE;
 180         palmas_gpio->gpio_chip.label = dev_name(&pdev->dev);
 181         palmas_gpio->gpio_chip.ngpio = dev_data->ngpio;
 182         palmas_gpio->gpio_chip.can_sleep = true;
 183         palmas_gpio->gpio_chip.direction_input = palmas_gpio_input;
 184         palmas_gpio->gpio_chip.direction_output = palmas_gpio_output;
 185         palmas_gpio->gpio_chip.to_irq = palmas_gpio_to_irq;
 186         palmas_gpio->gpio_chip.set      = palmas_gpio_set;
 187         palmas_gpio->gpio_chip.get      = palmas_gpio_get;
 188         palmas_gpio->gpio_chip.parent = &pdev->dev;
 189 #ifdef CONFIG_OF_GPIO
 190         palmas_gpio->gpio_chip.of_node = pdev->dev.of_node;
 191 #endif
 192         palmas_pdata = dev_get_platdata(palmas->dev);
 193         if (palmas_pdata && palmas_pdata->gpio_base)
 194                 palmas_gpio->gpio_chip.base = palmas_pdata->gpio_base;
 195         else
 196                 palmas_gpio->gpio_chip.base = -1;
 197
 198         ret = devm_gpiochip_add_data(&pdev->dev, &palmas_gpio->gpio_chip,
 199                                      palmas_gpio);
 200         if (ret < 0) {
 201                 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
 202                 return ret;
 203         }
 204
 205         platform_set_drvdata(pdev, palmas_gpio);
 206         return ret;
 207 }
 208
 209 static struct platform_driver palmas_gpio_driver = {
 210         .driver.name    = "palmas-gpio",
 211         .driver.owner   = THIS_MODULE,
 212         .driver.of_match_table = of_palmas_gpio_match,
 213         .probe          = palmas_gpio_probe,
 214 };
 215
 216 static int __init palmas_gpio_init(void)
 217 {
 218         return platform_driver_register(&palmas_gpio_driver);
 219 }
 220 subsys_initcall(palmas_gpio_init);
 221
 222 static void __exit palmas_gpio_exit(void)
 223 {
 224         platform_driver_unregister(&palmas_gpio_driver);
 225 }
 226 module_exit(palmas_gpio_exit);
 227
 228 MODULE_ALIAS("platform:palmas-gpio");
 229 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
 230 MODULE_DESCRIPTION("GPIO driver for TI Palmas series PMICs");
 231 MODULE_LICENSE("GPL v2");