[PATCH v2] leds: ledtrig-heartbeat: Make top brightness adjustable

[Jacek Anaszewski]

LED class heartbeat trigger allowed only for blinking with max_brightness
value. This patch adds more flexibility by exploiting part of LED core
software blink infrastructure.

Signed-off-by: Jacek Anaszewski <j.anaszew...@samsung.com>
Cc: Pavel Machek <pa...@ucw.cz>
Cc: Hans de Goede <hdego...@redhat.com>
---
Changes since v1:
- after introduction of work_flags and new_blink_brightness properties
  this patch needs to be updated

 drivers/leds/trigger/ledtrig-heartbeat.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/leds/trigger/ledtrig-heartbeat.c 
b/drivers/leds/trigger/ledtrig-heartbeat.c
index c9f3862..e6f2f8b 100644
--- a/drivers/leds/trigger/ledtrig-heartbeat.c
+++ b/drivers/leds/trigger/ledtrig-heartbeat.c
@@ -43,6 +43,9 @@ static void led_heartbeat_function(unsigned long data)
                return;
        }
 
+       if (test_and_clear_bit(LED_BLINK_BRIGHTNESS_CHANGE, 
&led_cdev->work_flags))
+               led_cdev->blink_brightness = led_cdev->new_blink_brightness;
+
        /* acts like an actual heart beat -- ie thump-thump-pause... */
        switch (heartbeat_data->phase) {
        case 0:
@@ -59,26 +62,26 @@ static void led_heartbeat_function(unsigned long data)
                delay = msecs_to_jiffies(70);
                heartbeat_data->phase++;
                if (!heartbeat_data->invert)
-                       brightness = led_cdev->max_brightness;
+                       brightness = led_cdev->blink_brightness;
                break;
        case 1:
                delay = heartbeat_data->period / 4 - msecs_to_jiffies(70);
                heartbeat_data->phase++;
                if (heartbeat_data->invert)
-                       brightness = led_cdev->max_brightness;
+                       brightness = led_cdev->blink_brightness;
                break;
        case 2:
                delay = msecs_to_jiffies(70);
                heartbeat_data->phase++;
                if (!heartbeat_data->invert)
-                       brightness = led_cdev->max_brightness;
+                       brightness = led_cdev->blink_brightness;
                break;
        default:
                delay = heartbeat_data->period - heartbeat_data->period / 4 -
                        msecs_to_jiffies(70);
                heartbeat_data->phase = 0;
                if (heartbeat_data->invert)
-                       brightness = led_cdev->max_brightness;
+                       brightness = led_cdev->blink_brightness;
                break;
        }
 
@@ -133,7 +136,10 @@ static void heartbeat_trig_activate(struct led_classdev 
*led_cdev)
        setup_timer(&heartbeat_data->timer,
                    led_heartbeat_function, (unsigned long) led_cdev);
        heartbeat_data->phase = 0;
+       if (!led_cdev->blink_brightness)
+               led_cdev->blink_brightness = led_cdev->max_brightness;
        led_heartbeat_function(heartbeat_data->timer.data);
+       set_bit(LED_BLINK_SW, &led_cdev->work_flags);
        led_cdev->activated = true;
 }
 
@@ -145,6 +151,7 @@ static void heartbeat_trig_deactivate(struct led_classdev 
*led_cdev)
                del_timer_sync(&heartbeat_data->timer);
                device_remove_file(led_cdev->dev, &dev_attr_invert);
                kfree(heartbeat_data);
+               clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
                led_cdev->activated = false;
        }
 }
-- 
1.9.1