1/*
  2 * Driver for the 8 user LEDs found on the RealViews and Versatiles
  3 * Based on DaVinci's DM365 board code
  4 *
  5 * License terms: GNU General Public License (GPL) version 2
  6 * Author: Linus Walleij <triad@df.lth.se>
  7 */
  8#include <linux/kernel.h>
  9#include <linux/init.h>
 10#include <linux/module.h>
 11#include <linux/io.h>
 12#include <linux/slab.h>
 13#include <linux/leds.h>
 14#include <linux/platform_device.h>
 15
 16struct versatile_led {
 17	void __iomem		*base;
 18	struct led_classdev	cdev;
 19	u8			mask;
 20};
 21
 22/*
 23 * The triggers lines up below will only be used if the
 24 * LED triggers are compiled in.
 25 */
 26static const struct {
 27	const char *name;
 28	const char *trigger;
 29} versatile_leds[] = {
 30	{ "versatile:0", "heartbeat", },
 31	{ "versatile:1", "mmc0", },
 32	{ "versatile:2", "cpu0" },
 33	{ "versatile:3", "cpu1" },
 34	{ "versatile:4", "cpu2" },
 35	{ "versatile:5", "cpu3" },
 36	{ "versatile:6", },
 37	{ "versatile:7", },
 38};
 39
 40static void versatile_led_set(struct led_classdev *cdev,
 41			      enum led_brightness b)
 42{
 43	struct versatile_led *led = container_of(cdev,
 44						 struct versatile_led, cdev);
 45	u32 reg = readl(led->base);
 46
 47	if (b != LED_OFF)
 48		reg |= led->mask;
 49	else
 50		reg &= ~led->mask;
 51	writel(reg, led->base);
 52}
 53
 54static enum led_brightness versatile_led_get(struct led_classdev *cdev)
 55{
 56	struct versatile_led *led = container_of(cdev,
 57						 struct versatile_led, cdev);
 58	u32 reg = readl(led->base);
 59
 60	return (reg & led->mask) ? LED_FULL : LED_OFF;
 61}
 62
 63static int versatile_leds_probe(struct platform_device *dev)
 64{
 65	int i;
 66	struct resource *res;
 67	void __iomem *base;
 68
 69	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
 70	base = devm_ioremap_resource(&dev->dev, res);
 71	if (IS_ERR(base))
 72		return PTR_ERR(base);
 73
 74	/* All off */
 75	writel(0, base);
 76	for (i = 0; i < ARRAY_SIZE(versatile_leds); i++) {
 77		struct versatile_led *led;
 78
 79		led = kzalloc(sizeof(*led), GFP_KERNEL);
 80		if (!led)
 81			break;
 82
 83		led->base = base;
 84		led->cdev.name = versatile_leds[i].name;
 85		led->cdev.brightness_set = versatile_led_set;
 86		led->cdev.brightness_get = versatile_led_get;
 87		led->cdev.default_trigger = versatile_leds[i].trigger;
 88		led->mask = BIT(i);
 89
 90		if (led_classdev_register(NULL, &led->cdev) < 0) {
 91			kfree(led);
 92			break;
 93		}
 94	}
 95
 96	return 0;
 97}
 98
 99static struct platform_driver versatile_leds_driver = {
100	.driver = {
101		.name   = "versatile-leds",
102	},
103	.probe = versatile_leds_probe,
104};
105
106module_platform_driver(versatile_leds_driver);
107
108MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
109MODULE_DESCRIPTION("ARM Versatile LED driver");
110MODULE_LICENSE("GPL v2");