LXR linux/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
  31struct rc5t583_gpio {
  32        struct gpio_chip gpio_chip;
  33        struct rc5t583 *rc5t583;
  34};
  35
  36static 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
  50static 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
  60static 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
  74static 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
  90static 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
 100static 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
 108static 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
 142static struct platform_driver rc5t583_gpio_driver = {
 143        .driver = {
 144                .name    = "rc5t583-gpio",
 145        },
 146        .probe          = rc5t583_gpio_probe,
 147};
 148
 149static int __init rc5t583_gpio_init(void)
 150{
 151        return platform_driver_register(&rc5t583_gpio_driver);
 152}
 153subsys_initcall(rc5t583_gpio_init);
 154