This patch rearranges the core LED subsystem code, so that it now shifts the responsibility for using work queues from drivers, in case their brightness_set ops can sleep, onto the LED core Addition of two flags: LED_BRIGHTNESS_FAST and LED_BLINK_DISABLE as well as new_brightness_value property to the struct led_classdev allows for employing existing set_brightness_work to do the job. The modifications allows also to get rid of brightness_set_sync op, as flash LED devices can now be handled properly only basing on the SET_BRIGHTNESS_SYNC flag.
Signed-off-by: Jacek Anaszewski <[email protected]> --- drivers/leds/led-class.c | 18 +++++++---- drivers/leds/led-core.c | 50 +++++++++++++++++------------ drivers/leds/leds.h | 41 +++++++++++++---------- drivers/leds/trigger/ledtrig-backlight.c | 8 ++--- drivers/leds/trigger/ledtrig-default-on.c | 2 +- drivers/leds/trigger/ledtrig-gpio.c | 6 ++-- drivers/leds/trigger/ledtrig-heartbeat.c | 4 +-- drivers/leds/trigger/ledtrig-oneshot.c | 4 +-- drivers/leds/trigger/ledtrig-transient.c | 8 ++--- include/linux/leds.h | 9 ++---- 10 files changed, 84 insertions(+), 66 deletions(-) diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c index beabfbc..07ccaeb 100644 --- a/drivers/leds/led-class.c +++ b/drivers/leds/led-class.c @@ -109,7 +109,7 @@ static void led_timer_function(unsigned long data) unsigned long delay; if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) { - led_set_brightness_async(led_cdev, LED_OFF); + led_set_brightness_nosleep(led_cdev, LED_OFF); return; } @@ -121,10 +121,10 @@ static void led_timer_function(unsigned long data) brightness = led_get_brightness(led_cdev); if (!brightness) { /* Time to switch the LED on. */ - if (led_cdev->delayed_set_value) { + if (led_cdev->new_brightness_value) { led_cdev->blink_brightness = - led_cdev->delayed_set_value; - led_cdev->delayed_set_value = 0; + led_cdev->new_brightness_value; + led_cdev->new_brightness_value = 0; } brightness = led_cdev->blink_brightness; delay = led_cdev->blink_delay_on; @@ -137,7 +137,7 @@ static void led_timer_function(unsigned long data) delay = led_cdev->blink_delay_off; } - led_set_brightness_async(led_cdev, brightness); + led_set_brightness_nosleep(led_cdev, brightness); /* Return in next iteration if led is in one-shot mode and we are in * the final blink state so that the led is toggled each delay_on + @@ -161,9 +161,13 @@ static void set_brightness_delayed(struct work_struct *ws) struct led_classdev *led_cdev = container_of(ws, struct led_classdev, set_brightness_work); - led_stop_software_blink(led_cdev); + if (led_cdev->flags & LED_BLINK_DISABLE) { + led_stop_software_blink(led_cdev); + led_cdev->flags &= ~LED_BLINK_DISABLE; + return; + } - led_set_brightness_async(led_cdev, led_cdev->delayed_set_value); + __led_set_brightness(led_cdev, led_cdev->delayed_set_value); } /** diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c index 549de7e..0e13fb0 100644 --- a/drivers/leds/led-core.c +++ b/drivers/leds/led-core.c @@ -42,13 +42,14 @@ static void led_set_software_blink(struct led_classdev *led_cdev, /* never on - just set to off */ if (!delay_on) { - led_set_brightness_async(led_cdev, LED_OFF); + led_set_brightness_nosleep(led_cdev, LED_OFF); return; } /* never off - just set to brightness */ if (!delay_off) { - led_set_brightness_async(led_cdev, led_cdev->blink_brightness); + led_set_brightness_nosleep(led_cdev, + led_cdev->blink_brightness); return; } @@ -117,27 +118,36 @@ EXPORT_SYMBOL_GPL(led_stop_software_blink); void led_set_brightness(struct led_classdev *led_cdev, enum led_brightness brightness) { - int ret = 0; - - /* delay brightness if soft-blink is active */ + /* + * In case blinking is on delay brightness setting + * to the next timer tick. + */ if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) { - led_cdev->delayed_set_value = brightness; - if (brightness == LED_OFF) - schedule_work(&led_cdev->set_brightness_work); - return; + led_cdev->new_brightness_value = brightness; + + /* New brightness will be set on next timer tick. */ + if (brightness != LED_OFF) + return; + /* + * If need to disable soft blinking delegate this to the + * work queue task to avoid problems in case we are + * called from hard irq context. + */ + led_cdev->flags |= LED_BLINK_DISABLE; + } else { + /* + * Don't use work queue if brightness has to be set as quickly + * as possible or if this is fast LED. + */ + if ((led_cdev->flags & SET_BRIGHTNESS_SYNC) || + (led_cdev->flags & LED_BRIGHTNESS_FAST)) { + __led_set_brightness(led_cdev, brightness); + return; + } } - if (led_cdev->flags & SET_BRIGHTNESS_ASYNC) { - led_set_brightness_async(led_cdev, brightness); - return; - } else if (led_cdev->flags & SET_BRIGHTNESS_SYNC) - ret = led_set_brightness_sync(led_cdev, brightness); - else - ret = -EINVAL; - - if (ret < 0) - dev_dbg(led_cdev->dev, "Setting LED brightness failed (%d)\n", - ret); + led_cdev->delayed_set_value = brightness; + schedule_work(&led_cdev->set_brightness_work); } EXPORT_SYMBOL(led_set_brightness); diff --git a/drivers/leds/leds.h b/drivers/leds/leds.h index bc89d7a..dd9dd9b 100644 --- a/drivers/leds/leds.h +++ b/drivers/leds/leds.h @@ -2,8 +2,10 @@ * LED Core * * Copyright 2005 Openedhand Ltd. + * Copyright 2014, 2015 Samsung Electronics Co., Ltd. * * Author: Richard Purdie <[email protected]> + * Author: Jacek Anaszewski <[email protected]> * * 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 @@ -16,27 +18,15 @@ #include <linux/rwsem.h> #include <linux/leds.h> -static inline void led_set_brightness_async(struct led_classdev *led_cdev, +static inline void __led_set_brightness(struct led_classdev *led_cdev, enum led_brightness value) { - value = min(value, led_cdev->max_brightness); - led_cdev->brightness = value; - - if (!(led_cdev->flags & LED_SUSPENDED)) - led_cdev->brightness_set(led_cdev, value); -} - -static inline int led_set_brightness_sync(struct led_classdev *led_cdev, - enum led_brightness value) -{ - int ret = 0; - led_cdev->brightness = min(value, led_cdev->max_brightness); - if (!(led_cdev->flags & LED_SUSPENDED)) - ret = led_cdev->brightness_set_sync(led_cdev, - led_cdev->brightness); - return ret; + if (led_cdev->flags & LED_SUSPENDED) + return; + + led_cdev->brightness_set(led_cdev, led_cdev->brightness); } static inline int led_get_brightness(struct led_classdev *led_cdev) @@ -44,6 +34,23 @@ static inline int led_get_brightness(struct led_classdev *led_cdev) return led_cdev->brightness; } +static inline void led_set_brightness_nosleep(struct led_classdev *led_cdev, + enum led_brightness value) +{ + /* + * Delegate setting brightness to a work queue task only for slow LEDs + * as the FAST ones are guaranteed not to sleep while setting + * brightness. + */ + if (!(led_cdev->flags & LED_BRIGHTNESS_FAST)) { + led_cdev->delayed_set_value = value; + schedule_work(&led_cdev->set_brightness_work); + return; + } + + __led_set_brightness(led_cdev, value); +} + void led_stop_software_blink(struct led_classdev *led_cdev); extern struct rw_semaphore leds_list_lock; diff --git a/drivers/leds/trigger/ledtrig-backlight.c b/drivers/leds/trigger/ledtrig-backlight.c index 59eca17..1ca1f16 100644 --- a/drivers/leds/trigger/ledtrig-backlight.c +++ b/drivers/leds/trigger/ledtrig-backlight.c @@ -51,9 +51,9 @@ static int fb_notifier_callback(struct notifier_block *p, if ((n->old_status == UNBLANK) ^ n->invert) { n->brightness = led->brightness; - led_set_brightness_async(led, LED_OFF); + led_set_brightness_nosleep(led, LED_OFF); } else { - led_set_brightness_async(led, n->brightness); + led_set_brightness_nosleep(led, n->brightness); } n->old_status = new_status; @@ -89,9 +89,9 @@ static ssize_t bl_trig_invert_store(struct device *dev, /* After inverting, we need to update the LED. */ if ((n->old_status == BLANK) ^ n->invert) - led_set_brightness_async(led, LED_OFF); + led_set_brightness_nosleep(led, LED_OFF); else - led_set_brightness_async(led, n->brightness); + led_set_brightness_nosleep(led, n->brightness); return num; } diff --git a/drivers/leds/trigger/ledtrig-default-on.c b/drivers/leds/trigger/ledtrig-default-on.c index 6f38f88..ff455cb 100644 --- a/drivers/leds/trigger/ledtrig-default-on.c +++ b/drivers/leds/trigger/ledtrig-default-on.c @@ -19,7 +19,7 @@ static void defon_trig_activate(struct led_classdev *led_cdev) { - led_set_brightness_async(led_cdev, led_cdev->max_brightness); + led_set_brightness_nosleep(led_cdev, led_cdev->max_brightness); } static struct led_trigger defon_led_trigger = { diff --git a/drivers/leds/trigger/ledtrig-gpio.c b/drivers/leds/trigger/ledtrig-gpio.c index 4cc7040..51288a4 100644 --- a/drivers/leds/trigger/ledtrig-gpio.c +++ b/drivers/leds/trigger/ledtrig-gpio.c @@ -54,12 +54,12 @@ static void gpio_trig_work(struct work_struct *work) if (tmp) { if (gpio_data->desired_brightness) - led_set_brightness_async(gpio_data->led, + led_set_brightness_nosleep(gpio_data->led, gpio_data->desired_brightness); else - led_set_brightness_async(gpio_data->led, LED_FULL); + led_set_brightness_nosleep(gpio_data->led, LED_FULL); } else { - led_set_brightness_async(gpio_data->led, LED_OFF); + led_set_brightness_nosleep(gpio_data->led, LED_OFF); } } diff --git a/drivers/leds/trigger/ledtrig-heartbeat.c b/drivers/leds/trigger/ledtrig-heartbeat.c index fea6871..3dc6f0c 100644 --- a/drivers/leds/trigger/ledtrig-heartbeat.c +++ b/drivers/leds/trigger/ledtrig-heartbeat.c @@ -37,7 +37,7 @@ static void led_heartbeat_function(unsigned long data) unsigned long delay = 0; if (unlikely(panic_heartbeats)) { - led_set_brightness(led_cdev, LED_OFF); + led_set_brightness_nosleep(led_cdev, LED_OFF); return; } @@ -74,7 +74,7 @@ static void led_heartbeat_function(unsigned long data) break; } - led_set_brightness_async(led_cdev, brightness); + led_set_brightness_nosleep(led_cdev, brightness); mod_timer(&heartbeat_data->timer, jiffies + delay); } diff --git a/drivers/leds/trigger/ledtrig-oneshot.c b/drivers/leds/trigger/ledtrig-oneshot.c index fbd02cd..6729317 100644 --- a/drivers/leds/trigger/ledtrig-oneshot.c +++ b/drivers/leds/trigger/ledtrig-oneshot.c @@ -63,9 +63,9 @@ static ssize_t led_invert_store(struct device *dev, oneshot_data->invert = !!state; if (oneshot_data->invert) - led_set_brightness_async(led_cdev, LED_FULL); + led_set_brightness_nosleep(led_cdev, LED_FULL); else - led_set_brightness_async(led_cdev, LED_OFF); + led_set_brightness_nosleep(led_cdev, LED_OFF); return size; } diff --git a/drivers/leds/trigger/ledtrig-transient.c b/drivers/leds/trigger/ledtrig-transient.c index 3c34de4..1dddd8f 100644 --- a/drivers/leds/trigger/ledtrig-transient.c +++ b/drivers/leds/trigger/ledtrig-transient.c @@ -41,7 +41,7 @@ static void transient_timer_function(unsigned long data) struct transient_trig_data *transient_data = led_cdev->trigger_data; transient_data->activate = 0; - led_set_brightness_async(led_cdev, transient_data->restore_state); + led_set_brightness_nosleep(led_cdev, transient_data->restore_state); } static ssize_t transient_activate_show(struct device *dev, @@ -72,7 +72,7 @@ static ssize_t transient_activate_store(struct device *dev, if (state == 0 && transient_data->activate == 1) { del_timer(&transient_data->timer); transient_data->activate = state; - led_set_brightness_async(led_cdev, + led_set_brightness_nosleep(led_cdev, transient_data->restore_state); return size; } @@ -81,7 +81,7 @@ static ssize_t transient_activate_store(struct device *dev, if (state == 1 && transient_data->activate == 0 && transient_data->duration != 0) { transient_data->activate = state; - led_set_brightness_async(led_cdev, transient_data->state); + led_set_brightness_nosleep(led_cdev, transient_data->state); transient_data->restore_state = (transient_data->state == LED_FULL) ? LED_OFF : LED_FULL; mod_timer(&transient_data->timer, @@ -204,7 +204,7 @@ static void transient_trig_deactivate(struct led_classdev *led_cdev) if (led_cdev->activated) { del_timer_sync(&transient_data->timer); - led_set_brightness_async(led_cdev, + led_set_brightness_nosleep(led_cdev, transient_data->restore_state); device_remove_file(led_cdev->dev, &dev_attr_activate); device_remove_file(led_cdev->dev, &dev_attr_duration); diff --git a/include/linux/leds.h b/include/linux/leds.h index b122eea..ea99de9 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -48,17 +48,13 @@ struct led_classdev { #define SET_BRIGHTNESS_ASYNC (1 << 21) #define SET_BRIGHTNESS_SYNC (1 << 22) #define LED_DEV_CAP_FLASH (1 << 23) +#define LED_BRIGHTNESS_FAST (1 << 24) +#define LED_BLINK_DISABLE (1 << 25) /* Set LED brightness level */ /* Must not sleep, use a workqueue if needed */ void (*brightness_set)(struct led_classdev *led_cdev, enum led_brightness brightness); - /* - * Set LED brightness level immediately - it can block the caller for - * the time required for accessing a LED device register. - */ - int (*brightness_set_sync)(struct led_classdev *led_cdev, - enum led_brightness brightness); /* Get LED brightness level */ enum led_brightness (*brightness_get)(struct led_classdev *led_cdev); @@ -87,6 +83,7 @@ struct led_classdev { struct work_struct set_brightness_work; int delayed_set_value; + int new_brightness_value; #ifdef CONFIG_LEDS_TRIGGERS /* Protects the trigger data below */ -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-leds" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
