diff options
author | Arnd Bergmann <arnd@arndb.de> | 2012-08-13 16:45:48 +0200 |
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committer | Arnd Bergmann <arnd@arndb.de> | 2012-08-13 16:45:48 +0200 |
commit | 19e4ab54e7f5fe46a3c931afa7e786f11d57b558 (patch) | |
tree | aeada0b9d0800b94cb795020a856c625ddc4f41c /drivers/leds | |
parent | 0d7614f09c1ebdbaa1599a5aba7593f147bf96ee (diff) | |
parent | fa8bbb13ab49e77c00fa09e5504ec25b7176fb4b (diff) |
Merge branch 'for-arm-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds into next/drivers
From Bryan Wu <bryan.wu@canonical.com>:
Based on Linus Walleij's ARM LED consolidation work, this patchset introduce a
new generic led trigger for CPU not only for ARM but also for others.
For enabling CPU idle event, CPU arch code should call ledtrig_cpu() stub to
trigger idle start or idle end event.
These patches convert old style LED driver in arch/arm to gpio_led or new led
driver interface. Against 3.5 release and build successfully for all the machines.
Test ledtrig-cpu driver on OMAP4 Panda board.
v9 --> v10
* fix compiling issue on versatile_defconfig reported by Russell King
* rebase to 3.5 kernel and move patches to new git tree
v8 --> v9:
* use mutex to replace rw_sema pointed out by Tim Gardner
* add a new struct led_trigger_cpu
* add lock_is_inited to record mutex lock initialization
v6 --> v7:
* add a patch to unify the led-trigger name
* fix some typo pointed
* use BUG_ON to detect CPU numbers during building stage
v5 --> v6:
* replace __get_cpu_var() to per_cpu()
* remove smp_processor_id() which is wrong with for_each_possible_cpu()
* test on real OMAP4 Panda board
* add comments about CPU hotplug in the CPU LED trigger driver
v4 --> v5:
* rebase all the patches on top of latest linux-next
* replace on_each_cpu() with for_each_possible_cpu()
* add some description of ledtrig_cpu() API
* remove old leds code from driver nwflash.c, which should use a new led trigger then
* this trigger driver can be built as module now
v3 --> v4:
* fix a typo pointed by Jochen Friedrich
* fix some building errors
* add Reviewed-by and Tested-by into patch log
v2 --> v3:
* almost rewrote the whole ledtrig-cpu driver, which is more simple
* every CPU will have a per-CPU trigger
* cpu trigger can be assigned to any leds
* fix a lockdep issue in led-trigger common code
* other fix according to review
v1 --> v2:
* remove select operations in Kconfig of every machines
* add back supporting of led in core module of mach-integrator
* solidate name scheme in ledtrig-cpu.c
* add comments of CPU_LED_* cpu led events
* fold patches of RealView and Versatile together
* add machine_is_ check during assabet led driver init
* add some Acked-by in patch logs
* remove code for simpad machine in machine-sa11000, since Jochen Friedrich
introduced gpiolib and gpio-led driver for simpad
* on Assabet and Netwinder machine, LED operations is reversed like:
setting bit means turn off leds
clearing bit means turn on leds
* add a new function to read CM_CTRL register for led driver
* 'for-arm-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds:
ARM: use new LEDS CPU trigger stub to replace old one
ARM: mach-sa1100: retire custom LED code
ARM: mach-omap1: retire custom LED code
ARM: mach-pnx4008: remove including old leds event API header file
ARM: plat-samsung: remove including old leds event API header file
ARM: mach-pxa: retire custom LED code
char: nwflash: remove old led event code
ARM: mach-footbridge: retire custom LED code
ARM: mach-ebsa110: retire custom LED code
ARM: mach-clps711x: retire custom LED code of P720T machine
ARM: mach-integrator: retire custom LED code
ARM: mach-integrator: move CM_CTRL to header file for accessing by other functions
ARM: mach-orion5x: convert custom LED code to gpio_led and LED CPU trigger
ARM: mach-shark: retire custom LED code
ARM: mach-ks8695: remove leds driver, since nobody use it
ARM: mach-realview and mach-versatile: retire custom LED code
ARM: at91: convert old leds drivers to gpio_led and led_trigger drivers
led-triggers: create a trigger for CPU activity
Conflicts:
arch/arm/mach-clps711x/p720t.c
arch/arm/mach-sa1100/leds-cerf.c
arch/arm/mach-sa1100/leds-lart.c
Let's hope this is the last time we pull this and it doesn't cause
more trouble. I have verified that version 10 causes no build
warnings or errors any more, and the patches still look good.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'drivers/leds')
-rw-r--r-- | drivers/leds/Kconfig | 10 | ||||
-rw-r--r-- | drivers/leds/Makefile | 1 | ||||
-rw-r--r-- | drivers/leds/ledtrig-cpu.c | 163 |
3 files changed, 174 insertions, 0 deletions
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index c96bbaadeebd..16578d3b52bb 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -506,6 +506,16 @@ config LEDS_TRIGGER_BACKLIGHT If unsure, say N. +config LEDS_TRIGGER_CPU + bool "LED CPU Trigger" + depends on LEDS_TRIGGERS + help + This allows LEDs to be controlled by active CPUs. This shows + the active CPUs across an array of LEDs so you can see which + CPUs are active on the system at any given moment. + + If unsure, say N. + config LEDS_TRIGGER_GPIO tristate "LED GPIO Trigger" depends on LEDS_TRIGGERS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index a4429a9217bc..a9b627c4f8ba 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -61,5 +61,6 @@ obj-$(CONFIG_LEDS_TRIGGER_IDE_DISK) += ledtrig-ide-disk.o obj-$(CONFIG_LEDS_TRIGGER_HEARTBEAT) += ledtrig-heartbeat.o obj-$(CONFIG_LEDS_TRIGGER_BACKLIGHT) += ledtrig-backlight.o obj-$(CONFIG_LEDS_TRIGGER_GPIO) += ledtrig-gpio.o +obj-$(CONFIG_LEDS_TRIGGER_CPU) += ledtrig-cpu.o obj-$(CONFIG_LEDS_TRIGGER_DEFAULT_ON) += ledtrig-default-on.o obj-$(CONFIG_LEDS_TRIGGER_TRANSIENT) += ledtrig-transient.o diff --git a/drivers/leds/ledtrig-cpu.c b/drivers/leds/ledtrig-cpu.c new file mode 100644 index 000000000000..b312056da14d --- /dev/null +++ b/drivers/leds/ledtrig-cpu.c @@ -0,0 +1,163 @@ +/* + * 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; + struct mutex lock; + int lock_is_inited; +}; + +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); + + /* mutex lock should be initialized before calling mutex_call() */ + if (!trig->lock_is_inited) + return; + + mutex_lock(&trig->lock); + + /* 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; + } + + mutex_unlock(&trig->lock); +} +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); + + mutex_init(&trig->lock); + + snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu); + + mutex_lock(&trig->lock); + led_trigger_register_simple(trig->name, &trig->_trig); + trig->lock_is_inited = 1; + mutex_unlock(&trig->lock); + } + + 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); + + mutex_lock(&trig->lock); + + led_trigger_unregister_simple(trig->_trig); + trig->_trig = NULL; + memset(trig->name, 0, MAX_NAME_LEN); + trig->lock_is_inited = 0; + + mutex_unlock(&trig->lock); + mutex_destroy(&trig->lock); + } + + 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"); |