Add generic support for color LED's.
Basic idea is to use enum led_brightness also for the hue and saturation
color components.This allows to implement the color extension w/o
changes to struct led_classdev.
Flag LED_BRIGHTNESS_SET_COLOR BIT(24) allows to specify that hue /
saturation should be overridden even if the provided values are zero.
Some examples for writing values to /sys/class/leds/<xx>/brightness:
(now also hex notation can be used)
255 -> set full brightness and keep existing color if set
0 -> switch LED off but keep existing color so that it can be restored
if the LED is switched on again later
0x1000000 -> switch LED off and set also hue and saturation to 0
0x00ffff -> set full brightness, full saturation and set hue to 0 (red)
Setting delayed_set_value in case of LED_BLINK_DISABLE was moved
to allow using the color information if provided by the caller
of led_set_brightness.
Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
---
drivers/leds/led-class.c | 7 +++++--
drivers/leds/led-core.c | 41 ++++++++++++++++++++++++++++++++++-------
include/linux/leds.h | 4 ++++
3 files changed, 43 insertions(+), 9 deletions(-)
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index aa84e5b..18a4558 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -32,7 +32,10 @@ static ssize_t brightness_show(struct device *dev,
/* no lock needed for this */
led_update_brightness(led_cdev);
- return sprintf(buf, "%u\n", led_cdev->brightness);
+ if (led_cdev->brightness > LED_FULL)
+ return sprintf(buf, "%#06x\n", led_cdev->brightness);
+ else
+ return sprintf(buf, "%u\n", led_cdev->brightness);
}
static ssize_t brightness_store(struct device *dev,
@@ -49,7 +52,7 @@ static ssize_t brightness_store(struct device *dev,
goto unlock;
}
- ret = kstrtoul(buf, 10, &state);
+ ret = kstrtoul(buf, 0, &state);
if (ret)
goto unlock;
diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c
index c29e4c9..798e31e 100644
--- a/drivers/leds/led-core.c
+++ b/drivers/leds/led-core.c
@@ -19,12 +19,32 @@
#include <linux/rwsem.h>
#include "leds.h"
+#define LED_HUE_SAT_MASK 0x00ffff00
+#define LED_BRIGHTNESS_MASK 0x000000ff
+
DECLARE_RWSEM(leds_list_lock);
EXPORT_SYMBOL_GPL(leds_list_lock);
LIST_HEAD(leds_list);
EXPORT_SYMBOL_GPL(leds_list);
+static inline enum led_brightness to_hsv(struct led_classdev *cdev,
+ enum led_brightness value)
+{
+ enum led_brightness ret;
+
+ /*
+ * if LED_BRIGHTNESS_SET_COLOR is set set hue and
+ * saturation even if both are zero
+ */
+ if (value & LED_BRIGHTNESS_SET_COLOR || value > LED_FULL)
+ ret = value & LED_HUE_SAT_MASK;
+ else
+ ret = cdev->brightness & ~LED_BRIGHTNESS_MASK;
+
+ return ret | min(value & LED_BRIGHTNESS_MASK, cdev->max_brightness);
+}
+
static int led_set_output(struct led_classdev *cdev,
enum led_brightness value)
{
@@ -62,7 +82,7 @@ static void led_timer_function(unsigned long data)
}
brightness = led_get_brightness(led_cdev);
- if (!brightness) {
+ if (!(brightness & LED_BRIGHTNESS_MASK)) {
/* Time to switch the LED on. */
brightness = led_cdev->blink_brightness;
delay = led_cdev->blink_delay_on;
@@ -106,7 +126,6 @@ static void set_brightness_delayed(struct work_struct *ws)
int ret = 0;
if (led_cdev->flags & LED_BLINK_DISABLE) {
- led_cdev->delayed_set_value = LED_OFF;
led_stop_software_blink(led_cdev);
led_cdev->flags &= ~LED_BLINK_DISABLE;
}
@@ -133,7 +152,7 @@ static void led_set_software_blink(struct led_classdev *led_cdev,
if (current_brightness)
led_cdev->blink_brightness = current_brightness;
if (!led_cdev->blink_brightness)
- led_cdev->blink_brightness = led_cdev->max_brightness;
+ led_cdev->blink_brightness = to_hsv(led_cdev, LED_FULL);
led_cdev->blink_delay_on = delay_on;
led_cdev->blink_delay_off = delay_off;
@@ -225,6 +244,8 @@ EXPORT_SYMBOL_GPL(led_stop_software_blink);
void led_set_brightness(struct led_classdev *led_cdev,
enum led_brightness brightness)
{
+ if (!(led_cdev->flags & LED_DEV_CAP_COLOR))
+ brightness &= LED_BRIGHTNESS_MASK;
/*
* In case blinking is on delay brightness setting
* until the next timer tick.
@@ -235,12 +256,15 @@ void led_set_brightness(struct led_classdev *led_cdev,
* work queue task to avoid problems in case we are called
* from hard irq context.
*/
- if (brightness == LED_OFF) {
+ if ((brightness & LED_BRIGHTNESS_MASK) == LED_OFF) {
led_cdev->flags |= LED_BLINK_DISABLE;
+ led_cdev->delayed_set_value =
+ to_hsv(led_cdev, brightness);
schedule_work(&led_cdev->set_brightness_work);
} else {
led_cdev->flags |= LED_BLINK_BRIGHTNESS_CHANGE;
- led_cdev->blink_brightness = brightness;
+ led_cdev->blink_brightness =
+ to_hsv(led_cdev, brightness);
}
return;
}
@@ -265,7 +289,7 @@ EXPORT_SYMBOL_GPL(led_set_brightness_nopm);
void led_set_brightness_nosleep(struct led_classdev *led_cdev,
enum led_brightness value)
{
- led_cdev->brightness = min(value, led_cdev->max_brightness);
+ led_cdev->brightness = to_hsv(led_cdev, value);
if (led_cdev->flags & LED_SUSPENDED)
return;
@@ -280,7 +304,10 @@ int led_set_brightness_sync(struct led_classdev *led_cdev,
if (led_cdev->blink_delay_on || led_cdev->blink_delay_off)
return -EBUSY;
- led_cdev->brightness = min(value, led_cdev->max_brightness);
+ if (!(led_cdev->flags & LED_DEV_CAP_COLOR))
+ value &= LED_BRIGHTNESS_MASK;
+
+ led_cdev->brightness = to_hsv(led_cdev, value);
if (led_cdev->flags & LED_SUSPENDED)
return 0;
diff --git a/include/linux/leds.h b/include/linux/leds.h
index f203a8f..8e7db72 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -50,6 +50,7 @@ struct led_classdev {
#define LED_SYSFS_DISABLE (1 << 22)
#define LED_DEV_CAP_FLASH (1 << 23)
#define LED_HW_PLUGGABLE (1 << 24)
+#define LED_DEV_CAP_COLOR (1 << 25)
/* Set LED brightness level
* Must not sleep. Use brightness_set_blocking for drivers
@@ -153,6 +154,9 @@ extern void led_blink_set_oneshot(struct led_classdev *led_cdev,
unsigned long *delay_on,
unsigned long *delay_off,
int invert);
+
+#define LED_BRIGHTNESS_SET_COLOR BIT(24)
+
/**
* led_set_brightness - set LED brightness
* @led_cdev: the LED to set
--
2.7.0
--
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