drivers/leds/leds-ip30.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * LED Driver for SGI Octane machines
   4  */
   5
   6 #include <asm/io.h>
   7 #include <linux/module.h>
   8 #include <linux/kernel.h>
   9 #include <linux/platform_device.h>
  10 #include <linux/leds.h>
  11
  12 #define IP30_LED_SYSTEM 0
  13 #define IP30_LED_FAULT  1
  14
  15 struct ip30_led {
  16         struct led_classdev cdev;
  17         u32 __iomem *reg;
  18 };
  19
  20 static void ip30led_set(struct led_classdev *led_cdev,
  21                         enum led_brightness value)
  22 {
  23         struct ip30_led *led = container_of(led_cdev, struct ip30_led, cdev);
  24
  25         writel(value, led->reg);
  26 }
  27
  28 static int ip30led_create(struct platform_device *pdev, int num)
  29 {
  30         struct ip30_led *data;
  31
  32         data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
  33         if (!data)
  34                 return -ENOMEM;
  35
  36         data->reg = devm_platform_ioremap_resource(pdev, num);
  37         if (IS_ERR(data->reg))
  38                 return PTR_ERR(data->reg);
  39
  40         switch (num) {
  41         case IP30_LED_SYSTEM:
  42                 data->cdev.name = "white:power";
  43                 break;
  44         case IP30_LED_FAULT:
  45                 data->cdev.name = "red:fault";
  46                 break;
  47         default:
  48                 return -EINVAL;
  49         }
  50
  51         data->cdev.brightness = readl(data->reg);
  52         data->cdev.max_brightness = 1;
  53         data->cdev.brightness_set = ip30led_set;
  54
  55         return devm_led_classdev_register(&pdev->dev, &data->cdev);
  56 }
  57
  58 static int ip30led_probe(struct platform_device *pdev)
  59 {
  60         int ret;
  61
  62         ret = ip30led_create(pdev, IP30_LED_SYSTEM);
  63         if (ret < 0)
  64                 return ret;
  65
  66         return ip30led_create(pdev, IP30_LED_FAULT);
  67 }
  68
  69 static struct platform_driver ip30led_driver = {
  70         .probe          = ip30led_probe,
  71         .driver         = {
  72                 .name           = "ip30-leds",
  73         },
  74 };
  75
  76 module_platform_driver(ip30led_driver);
  77
  78 MODULE_AUTHOR("Thomas Bogendoerfer <tbogendoerfer@suse.de>");
  79 MODULE_DESCRIPTION("SGI Octane LED driver");
  80 MODULE_LICENSE("GPL");
  81 MODULE_ALIAS("platform:ip30-leds");