kernel-ark/arch/arm/plat-versatile/leds.c
Bryan Wu e031cd513e ARM: mach-realview and mach-versatile: retire custom LED code
This replaces the custom LED trigger code in mach-realview with
some overarching platform code for the plat-versatile family that
will lock down LEDs 2 thru 5 for CPU activity indication. The
day we have 8 core ARM systems the plat-versatile code will have
to become more elaborate.

Tested on RealView PB11MPCore by invoking four different CPU
hogs (yes > /dev/null&) and see the LEDs go on one at a time.
They all go off as the hogs are killed. Tested on the PB1176
as well - just one activity led (led 2) goes on and off with
CPU activity.

(bryan.wu@canonical.com: use ledtrig-cpu instead of ledtrig-arm-cpu)

Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Acked-by: Pawel Moll <pawel.moll@arm.com>
2012-08-01 11:22:04 +08:00

104 lines
2.3 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", "cpu0" },
{ "versatile:3", "cpu1" },
{ "versatile:4", "cpu2" },
{ "versatile:5", "cpu3" },
{ "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);