drivers/gpio/gpio-rc5t583.c

   1 /*
   2  * GPIO driver for RICOH583 power management chip.
   3  *
   4  * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
   5  * Author: Laxman dewangan <ldewangan@nvidia.com>
   6  *
   7  * Based on code
   8  *      Copyright (C) 2011 RICOH COMPANY,LTD
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms and conditions of the GNU General Public License,
  12  * version 2, as published by the Free Software Foundation.
  13  *
  14  * This program is distributed in the hope it will be useful, but WITHOUT
  15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  17  * more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21  *
  22  */
  23 #include <linux/init.h>
  24 #include <linux/kernel.h>
  25 #include <linux/slab.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/device.h>
  28 #include <linux/gpio.h>
  29 #include <linux/mfd/rc5t583.h>
  30
  31 struct rc5t583_gpio {
  32         struct gpio_chip gpio_chip;
  33         struct rc5t583 *rc5t583;
  34 };
  35
  36 static int rc5t583_gpio_get(struct gpio_chip *gc, unsigned int offset)
  37 {
  38         struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
  39         struct device *parent = rc5t583_gpio->rc5t583->dev;
  40         uint8_t val = 0;
  41         int ret;
  42
  43         ret = rc5t583_read(parent, RC5T583_GPIO_MON_IOIN, &val);
  44         if (ret < 0)
  45                 return ret;
  46
  47         return !!(val & BIT(offset));
  48 }
  49
  50 static void rc5t583_gpio_set(struct gpio_chip *gc, unsigned int offset, int val)
  51 {
  52         struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
  53         struct device *parent = rc5t583_gpio->rc5t583->dev;
  54         if (val)
  55                 rc5t583_set_bits(parent, RC5T583_GPIO_IOOUT, BIT(offset));
  56         else
  57                 rc5t583_clear_bits(parent, RC5T583_GPIO_IOOUT, BIT(offset));
  58 }
  59
  60 static int rc5t583_gpio_dir_input(struct gpio_chip *gc, unsigned int offset)
  61 {
  62         struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
  63         struct device *parent = rc5t583_gpio->rc5t583->dev;
  64         int ret;
  65
  66         ret = rc5t583_clear_bits(parent, RC5T583_GPIO_IOSEL, BIT(offset));
  67         if (ret < 0)
  68                 return ret;
  69
  70         /* Set pin to gpio mode */
  71         return rc5t583_clear_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset));
  72 }
  73
  74 static int rc5t583_gpio_dir_output(struct gpio_chip *gc, unsigned offset,
  75                         int value)
  76 {
  77         struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
  78         struct device *parent = rc5t583_gpio->rc5t583->dev;
  79         int ret;
  80
  81         rc5t583_gpio_set(gc, offset, value);
  82         ret = rc5t583_set_bits(parent, RC5T583_GPIO_IOSEL, BIT(offset));
  83         if (ret < 0)
  84                 return ret;
  85
  86         /* Set pin to gpio mode */
  87         return rc5t583_clear_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset));
  88 }
  89
  90 static int rc5t583_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
  91 {
  92         struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
  93
  94         if (offset < RC5T583_MAX_GPIO)
  95                 return rc5t583_gpio->rc5t583->irq_base +
  96                                 RC5T583_IRQ_GPIO0 + offset;
  97         return -EINVAL;
  98 }
  99
 100 static void rc5t583_gpio_free(struct gpio_chip *gc, unsigned offset)
 101 {
 102         struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
 103         struct device *parent = rc5t583_gpio->rc5t583->dev;
 104
 105         rc5t583_set_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset));
 106 }
 107
 108 static int rc5t583_gpio_probe(struct platform_device *pdev)
 109 {
 110         struct rc5t583 *rc5t583 = dev_get_drvdata(pdev->dev.parent);
 111         struct rc5t583_platform_data *pdata = dev_get_platdata(rc5t583->dev);
 112         struct rc5t583_gpio *rc5t583_gpio;
 113
 114         rc5t583_gpio = devm_kzalloc(&pdev->dev, sizeof(*rc5t583_gpio),
 115                                         GFP_KERNEL);
 116         if (!rc5t583_gpio)
 117                 return -ENOMEM;
 118
 119         rc5t583_gpio->gpio_chip.label = "gpio-rc5t583",
 120         rc5t583_gpio->gpio_chip.owner = THIS_MODULE,
 121         rc5t583_gpio->gpio_chip.free = rc5t583_gpio_free,
 122         rc5t583_gpio->gpio_chip.direction_input = rc5t583_gpio_dir_input,
 123         rc5t583_gpio->gpio_chip.direction_output = rc5t583_gpio_dir_output,
 124         rc5t583_gpio->gpio_chip.set = rc5t583_gpio_set,
 125         rc5t583_gpio->gpio_chip.get = rc5t583_gpio_get,
 126         rc5t583_gpio->gpio_chip.to_irq = rc5t583_gpio_to_irq,
 127         rc5t583_gpio->gpio_chip.ngpio = RC5T583_MAX_GPIO,
 128         rc5t583_gpio->gpio_chip.can_sleep = true,
 129         rc5t583_gpio->gpio_chip.parent = &pdev->dev;
 130         rc5t583_gpio->gpio_chip.base = -1;
 131         rc5t583_gpio->rc5t583 = rc5t583;
 132
 133         if (pdata && pdata->gpio_base)
 134                 rc5t583_gpio->gpio_chip.base = pdata->gpio_base;
 135
 136         platform_set_drvdata(pdev, rc5t583_gpio);
 137
 138         return devm_gpiochip_add_data(&pdev->dev, &rc5t583_gpio->gpio_chip,
 139                                       rc5t583_gpio);
 140 }
 141
 142 static struct platform_driver rc5t583_gpio_driver = {
 143         .driver = {
 144                 .name    = "rc5t583-gpio",
 145         },
 146         .probe          = rc5t583_gpio_probe,
 147 };
 148
 149 static int __init rc5t583_gpio_init(void)
 150 {
 151         return platform_driver_register(&rc5t583_gpio_driver);
 152 }
 153 subsys_initcall(rc5t583_gpio_init);