linux/drivers/leds/leds-s3c24xx.c
<<
>>
Prefs
   1/* drivers/leds/leds-s3c24xx.c
   2 *
   3 * (c) 2006 Simtec Electronics
   4 *      http://armlinux.simtec.co.uk/
   5 *      Ben Dooks <ben@simtec.co.uk>
   6 *
   7 * S3C24XX - LEDs GPIO driver
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12*/
  13
  14#include <linux/kernel.h>
  15#include <linux/init.h>
  16#include <linux/platform_device.h>
  17#include <linux/leds.h>
  18#include <linux/gpio.h>
  19#include <linux/slab.h>
  20#include <linux/module.h>
  21
  22#include <mach/hardware.h>
  23#include <mach/regs-gpio.h>
  24#include <linux/platform_data/leds-s3c24xx.h>
  25
  26/* our context */
  27
  28struct s3c24xx_gpio_led {
  29        struct led_classdev              cdev;
  30        struct s3c24xx_led_platdata     *pdata;
  31};
  32
  33static inline struct s3c24xx_gpio_led *pdev_to_gpio(struct platform_device *dev)
  34{
  35        return platform_get_drvdata(dev);
  36}
  37
  38static inline struct s3c24xx_gpio_led *to_gpio(struct led_classdev *led_cdev)
  39{
  40        return container_of(led_cdev, struct s3c24xx_gpio_led, cdev);
  41}
  42
  43static void s3c24xx_led_set(struct led_classdev *led_cdev,
  44                            enum led_brightness value)
  45{
  46        struct s3c24xx_gpio_led *led = to_gpio(led_cdev);
  47        struct s3c24xx_led_platdata *pd = led->pdata;
  48        int state = (value ? 1 : 0) ^ (pd->flags & S3C24XX_LEDF_ACTLOW);
  49
  50        /* there will be a short delay between setting the output and
  51         * going from output to input when using tristate. */
  52
  53        gpio_set_value(pd->gpio, state);
  54
  55        if (pd->flags & S3C24XX_LEDF_TRISTATE) {
  56                if (value)
  57                        gpio_direction_output(pd->gpio, state);
  58                else
  59                        gpio_direction_input(pd->gpio);
  60        }
  61}
  62
  63static int s3c24xx_led_remove(struct platform_device *dev)
  64{
  65        struct s3c24xx_gpio_led *led = pdev_to_gpio(dev);
  66
  67        led_classdev_unregister(&led->cdev);
  68
  69        return 0;
  70}
  71
  72static int s3c24xx_led_probe(struct platform_device *dev)
  73{
  74        struct s3c24xx_led_platdata *pdata = dev->dev.platform_data;
  75        struct s3c24xx_gpio_led *led;
  76        int ret;
  77
  78        led = devm_kzalloc(&dev->dev, sizeof(struct s3c24xx_gpio_led),
  79                           GFP_KERNEL);
  80        if (led == NULL) {
  81                dev_err(&dev->dev, "No memory for device\n");
  82                return -ENOMEM;
  83        }
  84
  85        platform_set_drvdata(dev, led);
  86
  87        led->cdev.brightness_set = s3c24xx_led_set;
  88        led->cdev.default_trigger = pdata->def_trigger;
  89        led->cdev.name = pdata->name;
  90        led->cdev.flags |= LED_CORE_SUSPENDRESUME;
  91
  92        led->pdata = pdata;
  93
  94        ret = devm_gpio_request(&dev->dev, pdata->gpio, "S3C24XX_LED");
  95        if (ret < 0)
  96                return ret;
  97
  98        /* no point in having a pull-up if we are always driving */
  99
 100        s3c_gpio_setpull(pdata->gpio, S3C_GPIO_PULL_NONE);
 101
 102        if (pdata->flags & S3C24XX_LEDF_TRISTATE)
 103                gpio_direction_input(pdata->gpio);
 104        else
 105                gpio_direction_output(pdata->gpio,
 106                        pdata->flags & S3C24XX_LEDF_ACTLOW ? 1 : 0);
 107
 108        /* register our new led device */
 109
 110        ret = led_classdev_register(&dev->dev, &led->cdev);
 111        if (ret < 0)
 112                dev_err(&dev->dev, "led_classdev_register failed\n");
 113
 114        return ret;
 115}
 116
 117static struct platform_driver s3c24xx_led_driver = {
 118        .probe          = s3c24xx_led_probe,
 119        .remove         = s3c24xx_led_remove,
 120        .driver         = {
 121                .name           = "s3c24xx_led",
 122                .owner          = THIS_MODULE,
 123        },
 124};
 125
 126module_platform_driver(s3c24xx_led_driver);
 127
 128MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
 129MODULE_DESCRIPTION("S3C24XX LED driver");
 130MODULE_LICENSE("GPL");
 131MODULE_ALIAS("platform:s3c24xx_led");
 132
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.