drivers/leds/leds-ip30.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * LED Driver for SGI Octane machines
0004  */
0005
0006 #include <asm/io.h>
0007 #include <linux/module.h>
0008 #include <linux/kernel.h>
0009 #include <linux/platform_device.h>
0010 #include <linux/leds.h>
0011
0012 #define IP30_LED_SYSTEM 0
0013 #define IP30_LED_FAULT  1
0014
0015 struct ip30_led {
0016     struct led_classdev cdev;
0017     u32 __iomem *reg;
0018 };
0019
0020 static void ip30led_set(struct led_classdev *led_cdev,
0021             enum led_brightness value)
0022 {
0023     struct ip30_led *led = container_of(led_cdev, struct ip30_led, cdev);
0024
0025     writel(value, led->reg);
0026 }
0027
0028 static int ip30led_create(struct platform_device *pdev, int num)
0029 {
0030     struct resource *res;
0031     struct ip30_led *data;
0032
0033     res = platform_get_resource(pdev, IORESOURCE_MEM, num);
0034     if (!res)
0035         return -EBUSY;
0036
0037     data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
0038     if (!data)
0039         return -ENOMEM;
0040
0041     data->reg = devm_ioremap_resource(&pdev->dev, res);
0042     if (IS_ERR(data->reg))
0043         return PTR_ERR(data->reg);
0044
0045
0046     switch (num) {
0047     case IP30_LED_SYSTEM:
0048         data->cdev.name = "white:power";
0049         break;
0050     case IP30_LED_FAULT:
0051         data->cdev.name = "red:fault";
0052         break;
0053     default:
0054         return -EINVAL;
0055     }
0056
0057     data->cdev.brightness = readl(data->reg);
0058     data->cdev.max_brightness = 1;
0059     data->cdev.brightness_set = ip30led_set;
0060
0061     return devm_led_classdev_register(&pdev->dev, &data->cdev);
0062 }
0063
0064 static int ip30led_probe(struct platform_device *pdev)
0065 {
0066     int ret;
0067
0068     ret = ip30led_create(pdev, IP30_LED_SYSTEM);
0069     if (ret < 0)
0070         return ret;
0071
0072     return ip30led_create(pdev, IP30_LED_FAULT);
0073 }
0074
0075 static struct platform_driver ip30led_driver = {
0076     .probe      = ip30led_probe,
0077     .driver     = {
0078         .name       = "ip30-leds",
0079     },
0080 };
0081
0082 module_platform_driver(ip30led_driver);
0083
0084 MODULE_AUTHOR("Thomas Bogendoerfer <tbogendoerfer@suse.de>");
0085 MODULE_DESCRIPTION("SGI Octane LED driver");
0086 MODULE_LICENSE("GPL");
0087 MODULE_ALIAS("platform:ip30-leds");