drivers/leds/leds-ip30.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * LED Driver for SGI Octane machines
   4  */
   5
   6 #include <linux/module.h>
   7 #include <linux/kernel.h>
   8 #include <linux/platform_device.h>
   9 #include <linux/leds.h>
  10
  11 #define IP30_LED_SYSTEM 0
  12 #define IP30_LED_FAULT  1
  13
  14 struct ip30_led {
  15         struct led_classdev cdev;
  16         u32 __iomem *reg;
  17 };
  18
  19 static void ip30led_set(struct led_classdev *led_cdev,
  20                         enum led_brightness value)
  21 {
  22         struct ip30_led *led = container_of(led_cdev, struct ip30_led, cdev);
  23
  24         writel(value, led->reg);
  25 }
  26
  27 static int ip30led_create(struct platform_device *pdev, int num)
  28 {
  29         struct resource *res;
  30         struct ip30_led *data;
  31
  32         res = platform_get_resource(pdev, IORESOURCE_MEM, num);
  33         if (!res)
  34                 return -EBUSY;
  35
  36         data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
  37         if (!data)
  38                 return -ENOMEM;
  39
  40         data->reg = devm_ioremap_resource(&pdev->dev, res);
  41         if (IS_ERR(data->reg))
  42                 return PTR_ERR(data->reg);
  43
  44
  45         switch (num) {
  46         case IP30_LED_SYSTEM:
  47                 data->cdev.name = "white:power";
  48                 break;
  49         case IP30_LED_FAULT:
  50                 data->cdev.name = "red:fault";
  51                 break;
  52         default:
  53                 return -EINVAL;
  54         }
  55
  56         data->cdev.brightness = readl(data->reg);
  57         data->cdev.max_brightness = 1;
  58         data->cdev.brightness_set = ip30led_set;
  59
  60         return devm_led_classdev_register(&pdev->dev, &data->cdev);
  61 }
  62
  63 static int ip30led_probe(struct platform_device *pdev)
  64 {
  65         int ret;
  66
  67         ret = ip30led_create(pdev, IP30_LED_SYSTEM);
  68         if (ret < 0)
  69                 return ret;
  70
  71         return ip30led_create(pdev, IP30_LED_FAULT);
  72 }
  73
  74 static struct platform_driver ip30led_driver = {
  75         .probe          = ip30led_probe,
  76         .driver         = {
  77                 .name           = "ip30-leds",
  78         },
  79 };
  80
  81 module_platform_driver(ip30led_driver);
  82
  83 MODULE_AUTHOR("Thomas Bogendoerfer <tbogendoerfer@suse.de>");
  84 MODULE_DESCRIPTION("SGI Octane LED driver");
  85 MODULE_LICENSE("GPL");
  86 MODULE_ALIAS("platform:ip30-leds");