diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-06 15:41:42 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-06 15:41:42 -0700 |
commit | 2b69703fea185bb0ae1af78ca2da41af677b9dff (patch) | |
tree | 26b13044a0a20bed5525638d193e776f31f70af2 /drivers/leds/trigger/ledtrig-cpu.c | |
parent | 30c67e93c526639aaac90fa873800104b7c16d16 (diff) | |
parent | df92d5ff5e70999274f53884cc2c40ae620a109a (diff) |
Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds
Pull LED subsystem updates from Bryan Wu:
- move LED trigger drivers into a new directory
- lp55xx common driver updates
- other led drivers updates and bug fixing
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds:
leds: leds-asic3: switch to using SIMPLE_DEV_PM_OPS
leds: leds-bd2802: add CONFIG_PM_SLEEP to suspend/resume functions
leds: lp55xx: configure the clock detection
leds: lp55xx: use common clock framework when external clock is used
leds: leds-ns2: fix oops at module removal
leds: leds-pwm: Defer led_pwm_set() if PWM can sleep
leds: lp55xx: fix the sysfs read operation
leds: lm355x, lm3642: support camera LED triggers for flash and torch
leds: add camera LED triggers
leds: trigger: use inline functions instead of macros
leds: tca6507: Use of_match_ptr() macro
leds: wm8350: Complain if we fail to reenable DCDC
leds: renesas: set gpio_request_one() flags param correctly
leds: leds-ns2: set devm_gpio_request_one() flags param correctly
leds: leds-lt3593: set devm_gpio_request_one() flags param correctly
leds: leds-bd2802: remove erroneous __exit annotation
leds: atmel-pwm: remove erroneous __exit annotation
leds: move LED trigger drivers into new subdirectory
leds: add new LP5562 LED driver
Diffstat (limited to 'drivers/leds/trigger/ledtrig-cpu.c')
-rw-r--r-- | drivers/leds/trigger/ledtrig-cpu.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/drivers/leds/trigger/ledtrig-cpu.c b/drivers/leds/trigger/ledtrig-cpu.c new file mode 100644 index 00000000000..118335eccc5 --- /dev/null +++ b/drivers/leds/trigger/ledtrig-cpu.c @@ -0,0 +1,142 @@ +/* + * ledtrig-cpu.c - LED trigger based on CPU activity + * + * This LED trigger will be registered for each possible CPU and named as + * cpu0, cpu1, cpu2, cpu3, etc. + * + * It can be bound to any LED just like other triggers using either a + * board file or via sysfs interface. + * + * An API named ledtrig_cpu is exported for any user, who want to add CPU + * activity indication in their code + * + * Copyright 2011 Linus Walleij <linus.walleij@linaro.org> + * Copyright 2011 - 2012 Bryan Wu <bryan.wu@canonical.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/percpu.h> +#include <linux/syscore_ops.h> +#include <linux/rwsem.h> +#include "../leds.h" + +#define MAX_NAME_LEN 8 + +struct led_trigger_cpu { + char name[MAX_NAME_LEN]; + struct led_trigger *_trig; +}; + +static DEFINE_PER_CPU(struct led_trigger_cpu, cpu_trig); + +/** + * ledtrig_cpu - emit a CPU event as a trigger + * @evt: CPU event to be emitted + * + * Emit a CPU event on a CPU core, which will trigger a + * binded LED to turn on or turn off. + */ +void ledtrig_cpu(enum cpu_led_event ledevt) +{ + struct led_trigger_cpu *trig = &__get_cpu_var(cpu_trig); + + /* Locate the correct CPU LED */ + switch (ledevt) { + case CPU_LED_IDLE_END: + case CPU_LED_START: + /* Will turn the LED on, max brightness */ + led_trigger_event(trig->_trig, LED_FULL); + break; + + case CPU_LED_IDLE_START: + case CPU_LED_STOP: + case CPU_LED_HALTED: + /* Will turn the LED off */ + led_trigger_event(trig->_trig, LED_OFF); + break; + + default: + /* Will leave the LED as it is */ + break; + } +} +EXPORT_SYMBOL(ledtrig_cpu); + +static int ledtrig_cpu_syscore_suspend(void) +{ + ledtrig_cpu(CPU_LED_STOP); + return 0; +} + +static void ledtrig_cpu_syscore_resume(void) +{ + ledtrig_cpu(CPU_LED_START); +} + +static void ledtrig_cpu_syscore_shutdown(void) +{ + ledtrig_cpu(CPU_LED_HALTED); +} + +static struct syscore_ops ledtrig_cpu_syscore_ops = { + .shutdown = ledtrig_cpu_syscore_shutdown, + .suspend = ledtrig_cpu_syscore_suspend, + .resume = ledtrig_cpu_syscore_resume, +}; + +static int __init ledtrig_cpu_init(void) +{ + int cpu; + + /* Supports up to 9999 cpu cores */ + BUILD_BUG_ON(CONFIG_NR_CPUS > 9999); + + /* + * Registering CPU led trigger for each CPU core here + * ignores CPU hotplug, but after this CPU hotplug works + * fine with this trigger. + */ + for_each_possible_cpu(cpu) { + struct led_trigger_cpu *trig = &per_cpu(cpu_trig, cpu); + + snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu); + + led_trigger_register_simple(trig->name, &trig->_trig); + } + + register_syscore_ops(&ledtrig_cpu_syscore_ops); + + pr_info("ledtrig-cpu: registered to indicate activity on CPUs\n"); + + return 0; +} +module_init(ledtrig_cpu_init); + +static void __exit ledtrig_cpu_exit(void) +{ + int cpu; + + for_each_possible_cpu(cpu) { + struct led_trigger_cpu *trig = &per_cpu(cpu_trig, cpu); + + led_trigger_unregister_simple(trig->_trig); + trig->_trig = NULL; + memset(trig->name, 0, MAX_NAME_LEN); + } + + unregister_syscore_ops(&ledtrig_cpu_syscore_ops); +} +module_exit(ledtrig_cpu_exit); + +MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>"); +MODULE_AUTHOR("Bryan Wu <bryan.wu@canonical.com>"); +MODULE_DESCRIPTION("CPU LED trigger"); +MODULE_LICENSE("GPL"); |