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/io.h>
 11#include <linux/slab.h>
 12#include <linux/leds.h>
 13
 14#include <mach/hardware.h>
 15#include <mach/platform.h>
 16
 17#ifdef VERSATILE_SYS_BASE
 18#define LEDREG	(__io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_LED_OFFSET)
 19#endif
 20
 21#ifdef REALVIEW_SYS_BASE
 22#define LEDREG	(__io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_LED_OFFSET)
 23#endif
 24
 25struct versatile_led {
 26	struct led_classdev	cdev;
 27	u8			mask;
 28};
 29
 30/*
 31 * The triggers lines up below will only be used if the
 32 * LED triggers are compiled in.
 33 */
 34static const struct {
 35	const char *name;
 36	const char *trigger;
 37} versatile_leds[] = {
 38	{ "versatile:0", "heartbeat", },
 39	{ "versatile:1", "mmc0", },
 40	{ "versatile:2", },
 41	{ "versatile:3", },
 42	{ "versatile:4", },
 43	{ "versatile:5", },
 44	{ "versatile:6", },
 45	{ "versatile:7", },
 46};
 47
 48static void versatile_led_set(struct led_classdev *cdev,
 49			      enum led_brightness b)
 50{
 51	struct versatile_led *led = container_of(cdev,
 52						 struct versatile_led, cdev);
 53	u32 reg = readl(LEDREG);
 54
 55	if (b != LED_OFF)
 56		reg |= led->mask;
 57	else
 58		reg &= ~led->mask;
 59	writel(reg, LEDREG);
 60}
 61
 62static enum led_brightness versatile_led_get(struct led_classdev *cdev)
 63{
 64	struct versatile_led *led = container_of(cdev,
 65						 struct versatile_led, cdev);
 66	u32 reg = readl(LEDREG);
 67
 68	return (reg & led->mask) ? LED_FULL : LED_OFF;
 69}
 70
 71static int __init versatile_leds_init(void)
 72{
 73	int i;
 74
 75	/* All ON */
 76	writel(0xff, LEDREG);
 77	for (i = 0; i < ARRAY_SIZE(versatile_leds); i++) {
 78		struct versatile_led *led;
 79
 80		led = kzalloc(sizeof(*led), GFP_KERNEL);
 81		if (!led)
 82			break;
 83
 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
 99/*
100 * Since we may have triggers on any subsystem, defer registration
101 * until after subsystem_init.
102 */
103fs_initcall(versatile_leds_init);