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 resource *res;
  31         struct ip30_led *data;
  32
  33         res = platform_get_resource(pdev, IORESOURCE_MEM, num);
  34         if (!res)
  35                 return -EBUSY;
  36
  37         data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
  38         if (!data)
  39                 return -ENOMEM;
  40
  41         data->reg = devm_ioremap_resource(&pdev->dev, res);
  42         if (IS_ERR(data->reg))
  43                 return PTR_ERR(data->reg);
  44
  45
  46         switch (num) {
  47         case IP30_LED_SYSTEM:
  48                 data->cdev.name = "white:power";
  49                 break;
  50         case IP30_LED_FAULT:
  51                 data->cdev.name = "red:fault";
  52                 break;
  53         default:
  54                 return -EINVAL;
  55         }
  56
  57         data->cdev.brightness = readl(data->reg);
  58         data->cdev.max_brightness = 1;
  59         data->cdev.brightness_set = ip30led_set;
  60
  61         return devm_led_classdev_register(&pdev->dev, &data->cdev);
  62 }
  63
  64 static int ip30led_probe(struct platform_device *pdev)
  65 {
  66         int ret;
  67
  68         ret = ip30led_create(pdev, IP30_LED_SYSTEM);
  69         if (ret < 0)
  70                 return ret;
  71
  72         return ip30led_create(pdev, IP30_LED_FAULT);
  73 }
  74
  75 static struct platform_driver ip30led_driver = {
  76         .probe          = ip30led_probe,
  77         .driver         = {
  78                 .name           = "ip30-leds",
  79         },
  80 };
  81
  82 module_platform_driver(ip30led_driver);
  83
  84 MODULE_AUTHOR("Thomas Bogendoerfer <tbogendoerfer@suse.de>");
  85 MODULE_DESCRIPTION("SGI Octane LED driver");
  86 MODULE_LICENSE("GPL");
  87 MODULE_ALIAS("platform:ip30-leds");