From 911a359de96d5e9d24f50c74a48c6f3cf061539a Mon Sep 17 00:00:00 2001 From: Richard Cochran Date: Wed, 13 Jul 2016 17:16:45 +0000 Subject: [PATCH] leds/trigger/cpu: Convert to hotplug state machine This is a straightforward conversion. We place this callback last in the list so that the LED illuminates only after a successful bring up sequence. ( NOTE: The patch adds a FIXME question about the callback used, this question should probably be revisited later on.) Signed-off-by: Richard Cochran Signed-off-by: Anna-Maria Gleixner Reviewed-by: Sebastian Andrzej Siewior Acked-by: Jacek Anaszewski Cc: Linus Torvalds Cc: Linus Walleij Cc: Paul Gortmaker Cc: Peter Zijlstra Cc: Richard Purdie Cc: Thomas Gleixner Cc: linux-leds@vger.kernel.org Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160713153336.465496902@linutronix.de Signed-off-by: Ingo Molnar --- drivers/leds/trigger/ledtrig-cpu.c | 32 ++++++++++++++---------------- include/linux/cpuhotplug.h | 1 + 2 files changed, 16 insertions(+), 17 deletions(-) diff --git a/drivers/leds/trigger/ledtrig-cpu.c b/drivers/leds/trigger/ledtrig-cpu.c index 938467fb82be..4a6a182d0a88 100644 --- a/drivers/leds/trigger/ledtrig-cpu.c +++ b/drivers/leds/trigger/ledtrig-cpu.c @@ -92,25 +92,17 @@ static struct syscore_ops ledtrig_cpu_syscore_ops = { .resume = ledtrig_cpu_syscore_resume, }; -static int ledtrig_cpu_notify(struct notifier_block *self, - unsigned long action, void *hcpu) +static int ledtrig_starting_cpu(unsigned int cpu) { - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_STARTING: - ledtrig_cpu(CPU_LED_START); - break; - case CPU_DYING: - ledtrig_cpu(CPU_LED_STOP); - break; - } - - return NOTIFY_OK; + ledtrig_cpu(CPU_LED_START); + return 0; } - -static struct notifier_block ledtrig_cpu_nb = { - .notifier_call = ledtrig_cpu_notify, -}; +static int ledtrig_dying_cpu(unsigned int cpu) +{ + ledtrig_cpu(CPU_LED_STOP); + return 0; +} static int __init ledtrig_cpu_init(void) { @@ -133,7 +125,13 @@ static int __init ledtrig_cpu_init(void) } register_syscore_ops(&ledtrig_cpu_syscore_ops); - register_cpu_notifier(&ledtrig_cpu_nb); + + /* + * FIXME: Why needs this to happen in the interrupt disabled + * low level bringup phase of a cpu? + */ + cpuhp_setup_state(CPUHP_AP_LEDTRIG_STARTING, "AP_LEDTRIG_STARTING", + ledtrig_starting_cpu, ledtrig_dying_cpu); pr_info("ledtrig-cpu: registered to indicate activity on CPUs\n"); diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 456e3d93272c..24f56e290003 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -42,6 +42,7 @@ enum cpuhp_state { CPUHP_AP_QCOM_TIMER_STARTING, CPUHP_AP_MIPS_GIC_TIMER_STARTING, CPUHP_AP_KVM_STARTING, + CPUHP_AP_LEDTRIG_STARTING, CPUHP_AP_NOTIFY_STARTING, CPUHP_AP_ONLINE, CPUHP_TEARDOWN_CPU,