diff options
Diffstat (limited to 'arch/arm/plat-mxc/leds.c')
-rw-r--r-- | arch/arm/plat-mxc/leds.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/arch/arm/plat-mxc/leds.c b/arch/arm/plat-mxc/leds.c new file mode 100644 index 000000000000..e059d238f82b --- /dev/null +++ b/arch/arm/plat-mxc/leds.c @@ -0,0 +1,111 @@ +/* + * Copyright 2007-2009 Freescale Semiconductor, Inc. All Rights Reserved. + */ + +/* + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +/* + * The LED can be used for debugging purpose. To enalbe the LEDs, in the + * config file, select: + * CONFIG_LEDS + * CONFIG_LEDS_TIMER --- enable the OS tick LED once every 50 ticks (.5sec) + * CONFIG_LEDS_CPU --- enable the cpu idle in/out LED (blink fast) + * + * The two LEDs can be disabled through user space by issuing: + * echo "claim" > /sys/devices/system/leds/leds0/event + * To release the LEDs back to the normal operation, do: + * echo "release" > /sys/devices/system/leds/leds0/event + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/ioport.h> +#include <asm/mach-types.h> +#include <mach/hardware.h> +#include <asm/leds.h> + +#define LED_STATE_ENABLED (1 << 0) +#define LED_STATE_CLAIMED (1 << 1) + +static unsigned int led_state; +static unsigned int hw_led_state; + +static void mxc_leds_event(led_event_t evt) +{ + unsigned long flags; + + local_irq_save(flags); + + switch (evt) { + case led_start: + hw_led_state = MXC_BD_LED1 | MXC_BD_LED2; + led_state = LED_STATE_ENABLED; + break; + + case led_stop: + case led_halted: + hw_led_state = 0; + led_state &= ~LED_STATE_ENABLED; + MXC_BD_LED_OFF(MXC_BD_LED1 | MXC_BD_LED2); + break; + + case led_claim: + led_state |= LED_STATE_CLAIMED; + hw_led_state = 0; + break; + + case led_release: + led_state &= ~LED_STATE_CLAIMED; + hw_led_state = 0; + break; + +#ifdef CONFIG_LEDS_TIMER + case led_timer: + if (!(led_state & LED_STATE_CLAIMED)) + hw_led_state ^= MXC_BD_LED1; + break; +#endif + +#ifdef CONFIG_LEDS_CPU + case led_idle_start: + if (!(led_state & LED_STATE_CLAIMED)) + hw_led_state &= ~MXC_BD_LED2; + break; + + case led_idle_end: + if (!(led_state & LED_STATE_CLAIMED)) + hw_led_state |= MXC_BD_LED2; + break; +#endif + + default: + break; + } + + if (led_state & LED_STATE_ENABLED) { + MXC_BD_LED_OFF(~hw_led_state); + MXC_BD_LED_ON(hw_led_state); + } + + local_irq_restore(flags); +} + +static int __init mxc_leds_init(void) +{ + led_state = LED_STATE_ENABLED; + leds_event = mxc_leds_event; + return 0; +} + +core_initcall(mxc_leds_init); |