linux-sg2042/arch/arm/plat-versatile/leds.c

104 lines
2.2 KiB
C

/*
* Driver for the 8 user LEDs found on the RealViews and Versatiles
* Based on DaVinci's DM365 board code
*
* License terms: GNU General Public License (GPL) version 2
* Author: Linus Walleij <triad@df.lth.se>
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/leds.h>
#include <mach/hardware.h>
#include <mach/platform.h>
#ifdef VERSATILE_SYS_BASE
#define LEDREG (__io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_LED_OFFSET)
#endif
#ifdef REALVIEW_SYS_BASE
#define LEDREG (__io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_LED_OFFSET)
#endif
struct versatile_led {
struct led_classdev cdev;
u8 mask;
};
/*
* The triggers lines up below will only be used if the
* LED triggers are compiled in.
*/
static const struct {
const char *name;
const char *trigger;
} versatile_leds[] = {
{ "versatile:0", "heartbeat", },
{ "versatile:1", "mmc0", },
{ "versatile:2", },
{ "versatile:3", },
{ "versatile:4", },
{ "versatile:5", },
{ "versatile:6", },
{ "versatile:7", },
};
static void versatile_led_set(struct led_classdev *cdev,
enum led_brightness b)
{
struct versatile_led *led = container_of(cdev,
struct versatile_led, cdev);
u32 reg = readl(LEDREG);
if (b != LED_OFF)
reg |= led->mask;
else
reg &= ~led->mask;
writel(reg, LEDREG);
}
static enum led_brightness versatile_led_get(struct led_classdev *cdev)
{
struct versatile_led *led = container_of(cdev,
struct versatile_led, cdev);
u32 reg = readl(LEDREG);
return (reg & led->mask) ? LED_FULL : LED_OFF;
}
static int __init versatile_leds_init(void)
{
int i;
/* All ON */
writel(0xff, LEDREG);
for (i = 0; i < ARRAY_SIZE(versatile_leds); i++) {
struct versatile_led *led;
led = kzalloc(sizeof(*led), GFP_KERNEL);
if (!led)
break;
led->cdev.name = versatile_leds[i].name;
led->cdev.brightness_set = versatile_led_set;
led->cdev.brightness_get = versatile_led_get;
led->cdev.default_trigger = versatile_leds[i].trigger;
led->mask = BIT(i);
if (led_classdev_register(NULL, &led->cdev) < 0) {
kfree(led);
break;
}
}
return 0;
}
/*
* Since we may have triggers on any subsystem, defer registration
* until after subsystem_init.
*/
fs_initcall(versatile_leds_init);