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/module.h>
  27#include <linux/platform_device.h>
  28#include <linux/device.h>
  29#include <linux/gpio.h>
  30#include <linux/mfd/rc5t583.h>
  31
  32struct rc5t583_gpio {
  33        struct gpio_chip gpio_chip;
  34        struct rc5t583 *rc5t583;
  35};
  36
  37static int rc5t583_gpio_get(struct gpio_chip *gc, unsigned int offset)
  38{
  39        struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
  40        struct device *parent = rc5t583_gpio->rc5t583->dev;
  41        uint8_t val = 0;
  42        int ret;
  43
  44        ret = rc5t583_read(parent, RC5T583_GPIO_MON_IOIN, &val);
  45        if (ret < 0)
  46                return ret;
  47
  48        return !!(val & BIT(offset));
  49}
  50
  51static void rc5t583_gpio_set(struct gpio_chip *gc, unsigned int offset, int val)
  52{
  53        struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
  54        struct device *parent = rc5t583_gpio->rc5t583->dev;
  55        if (val)
  56                rc5t583_set_bits(parent, RC5T583_GPIO_IOOUT, BIT(offset));
  57        else
  58                rc5t583_clear_bits(parent, RC5T583_GPIO_IOOUT, BIT(offset));
  59}
  60
  61static int rc5t583_gpio_dir_input(struct gpio_chip *gc, unsigned int offset)
  62{
  63        struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
  64        struct device *parent = rc5t583_gpio->rc5t583->dev;
  65        int ret;
  66
  67        ret = rc5t583_clear_bits(parent, RC5T583_GPIO_IOSEL, BIT(offset));
  68        if (ret < 0)
  69                return ret;
  70
  71        /* Set pin to gpio mode */
  72        return rc5t583_clear_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset));
  73}
  74
  75static int rc5t583_gpio_dir_output(struct gpio_chip *gc, unsigned offset,
  76                        int value)
  77{
  78        struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
  79        struct device *parent = rc5t583_gpio->rc5t583->dev;
  80        int ret;
  81
  82        rc5t583_gpio_set(gc, offset, value);
  83        ret = rc5t583_set_bits(parent, RC5T583_GPIO_IOSEL, BIT(offset));
  84        if (ret < 0)
  85                return ret;
  86
  87        /* Set pin to gpio mode */
  88        return rc5t583_clear_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset));
  89}
  90
  91static int rc5t583_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
  92{
  93        struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
  94
  95        if (offset < RC5T583_MAX_GPIO)
  96                return rc5t583_gpio->rc5t583->irq_base +
  97                                RC5T583_IRQ_GPIO0 + offset;
  98        return -EINVAL;
  99}
 100
 101static void rc5t583_gpio_free(struct gpio_chip *gc, unsigned offset)
 102{
 103        struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc);
 104        struct device *parent = rc5t583_gpio->rc5t583->dev;
 105
 106        rc5t583_set_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset));
 107}
 108
 109static int rc5t583_gpio_probe(struct platform_device *pdev)
 110{
 111        struct rc5t583 *rc5t583 = dev_get_drvdata(pdev->dev.parent);
 112        struct rc5t583_platform_data *pdata = dev_get_platdata(rc5t583->dev);
 113        struct rc5t583_gpio *rc5t583_gpio;
 114
 115        rc5t583_gpio = devm_kzalloc(&pdev->dev, sizeof(*rc5t583_gpio),
 116                                        GFP_KERNEL);
 117        if (!rc5t583_gpio)
 118                return -ENOMEM;
 119
 120        rc5t583_gpio->gpio_chip.label = "gpio-rc5t583",
 121        rc5t583_gpio->gpio_chip.owner = THIS_MODULE,
 122        rc5t583_gpio->gpio_chip.free = rc5t583_gpio_free,
 123        rc5t583_gpio->gpio_chip.direction_input = rc5t583_gpio_dir_input,
 124        rc5t583_gpio->gpio_chip.direction_output = rc5t583_gpio_dir_output,
 125        rc5t583_gpio->gpio_chip.set = rc5t583_gpio_set,
 126        rc5t583_gpio->gpio_chip.get = rc5t583_gpio_get,
 127        rc5t583_gpio->gpio_chip.to_irq = rc5t583_gpio_to_irq,
 128        rc5t583_gpio->gpio_chip.ngpio = RC5T583_MAX_GPIO,
 129        rc5t583_gpio->gpio_chip.can_sleep = true,
 130        rc5t583_gpio->gpio_chip.parent = &pdev->dev;
 131        rc5t583_gpio->gpio_chip.base = -1;
 132        rc5t583_gpio->rc5t583 = rc5t583;
 133
 134        if (pdata && pdata->gpio_base)
 135                rc5t583_gpio->gpio_chip.base = pdata->gpio_base;
 136
 137        platform_set_drvdata(pdev, rc5t583_gpio);
 138
 139        return devm_gpiochip_add_data(&pdev->dev, &rc5t583_gpio->gpio_chip,
 140                                      rc5t583_gpio);
 141}
 142
 143static struct platform_driver rc5t583_gpio_driver = {
 144        .driver = {
 145                .name    = "rc5t583-gpio",
 146        },
 147        .probe          = rc5t583_gpio_probe,
 148};
 149
 150static int __init rc5t583_gpio_init(void)
 151{
 152        return platform_driver_register(&rc5t583_gpio_driver);
 153}
 154subsys_initcall(rc5t583_gpio_init);
 155
 156static void __exit rc5t583_gpio_exit(void)
 157{
 158        platform_driver_unregister(&rc5t583_gpio_driver);
 159}
 160module_exit(rc5t583_gpio_exit);
 161
 162MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
 163MODULE_DESCRIPTION("GPIO interface for RC5T583");
 164MODULE_LICENSE("GPL v2");
 165MODULE_ALIAS("platform:rc5t583-gpio");
 166