drivers/staging/nvec/nvec_paz00.c

   1 /*
   2  * nvec_paz00: OEM specific driver for Compal PAZ00 based devices
   3  *
   4  * Copyright (C) 2011 The AC100 Kernel Team <ac100@lists.launchpad.net>
   5  *
   6  * Authors:  Ilya Petrov <ilya.muromec@gmail.com>
   7  *
   8  * This file is subject to the terms and conditions of the GNU General Public
   9  * License.  See the file "COPYING" in the main directory of this archive
  10  * for more details.
  11  *
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/err.h>
  16 #include <linux/slab.h>
  17 #include <linux/leds.h>
  18 #include <linux/platform_device.h>
  19 #include "nvec.h"
  20
  21 #define to_nvec_led(led_cdev) \
  22         container_of(led_cdev, struct nvec_led, cdev)
  23
  24 #define NVEC_LED_REQ {'\x0d', '\x10', '\x45', '\x10', '\x00'}
  25
  26 #define NVEC_LED_MAX 8
  27
  28 struct nvec_led {
  29         struct led_classdev cdev;
  30         struct nvec_chip *nvec;
  31 };
  32
  33 static void nvec_led_brightness_set(struct led_classdev *led_cdev,
  34                                     enum led_brightness value)
  35 {
  36         struct nvec_led *led = to_nvec_led(led_cdev);
  37         unsigned char buf[] = NVEC_LED_REQ;
  38
  39         buf[4] = value;
  40
  41         nvec_write_async(led->nvec, buf, sizeof(buf));
  42
  43         led->cdev.brightness = value;
  44 }
  45
  46 static int nvec_paz00_probe(struct platform_device *pdev)
  47 {
  48         struct nvec_chip *nvec = dev_get_drvdata(pdev->dev.parent);
  49         struct nvec_led *led;
  50         int ret = 0;
  51
  52         led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
  53         if (!led)
  54                 return -ENOMEM;
  55
  56         led->cdev.max_brightness = NVEC_LED_MAX;
  57
  58         led->cdev.brightness_set = nvec_led_brightness_set;
  59         led->cdev.name = "paz00-led";
  60         led->cdev.flags |= LED_CORE_SUSPENDRESUME;
  61         led->nvec = nvec;
  62
  63         platform_set_drvdata(pdev, led);
  64
  65         ret = devm_led_classdev_register(&pdev->dev, &led->cdev);
  66         if (ret < 0)
  67                 return ret;
  68
  69         /* to expose the default value to userspace */
  70         led->cdev.brightness = 0;
  71
  72         return 0;
  73 }
  74
  75 static struct platform_driver nvec_paz00_driver = {
  76         .probe  = nvec_paz00_probe,
  77         .driver = {
  78                 .name  = "nvec-paz00",
  79         },
  80 };
  81
  82 module_platform_driver(nvec_paz00_driver);
  83
  84 MODULE_AUTHOR("Ilya Petrov <ilya.muromec@gmail.com>");
  85 MODULE_DESCRIPTION("Tegra NVEC PAZ00 driver");
  86 MODULE_LICENSE("GPL");
  87 MODULE_ALIAS("platform:nvec-paz00");