Right now the driver uses only 3 LED modes:
0: On
1: HW Blinking (Interval 1)
3: Off
However, the controller supports a second HW blinking interval, which results
in 4 possible LED modes:
0: On
1: HW Blinking (Interval 1)
2: HW Blinking (Interval 2)
3: Off
Signed-off-by: Álvaro Fernández Rojas <noltari@xxxxxxxxx>
---
v5: add commit description including LED modes clarification
v4: improve code documentation and use blink instead of intervals, which
should make the code much more clear to understand
v3: add code documentation
v2: remove LED from the other blinking interval
drivers/leds/leds-bcm6328.c | 97 ++++++++++++++++++++++++++++---------
1 file changed, 75 insertions(+), 22 deletions(-)
diff --git a/drivers/leds/leds-bcm6328.c b/drivers/leds/leds-bcm6328.c
index 42e1b7598c3a..bad7efb75112 100644
--- a/drivers/leds/leds-bcm6328.c
+++ b/drivers/leds/leds-bcm6328.c
@@ -24,12 +24,17 @@
#define BCM6328_LED_MAX_COUNT 24
#define BCM6328_LED_DEF_DELAY 500
-#define BCM6328_LED_INTERVAL_MS 20
-#define BCM6328_LED_INTV_MASK 0x3f
-#define BCM6328_LED_FAST_INTV_SHIFT 6
-#define BCM6328_LED_FAST_INTV_MASK (BCM6328_LED_INTV_MASK << \
- BCM6328_LED_FAST_INTV_SHIFT)
+#define BCM6328_LED_BLINK_DELAYS 2
+#define BCM6328_LED_BLINK_MS 20
+
+#define BCM6328_LED_BLINK_MASK 0x3f
+#define BCM6328_LED_BLINK1_SHIFT 0
+#define BCM6328_LED_BLINK1_MASK (BCM6328_LED_BLINK_MASK << \
+ BCM6328_LED_BLINK1_SHIFT)
+#define BCM6328_LED_BLINK2_SHIFT 6
+#define BCM6328_LED_BLINK2_MASK (BCM6328_LED_BLINK_MASK << \
+ BCM6328_LED_BLINK2_SHIFT)
#define BCM6328_SERIAL_LED_EN BIT(12)
#define BCM6328_SERIAL_LED_MUX BIT(13)
#define BCM6328_SERIAL_LED_CLK_NPOL BIT(14)
@@ -45,8 +50,8 @@
#define BCM6328_LED_MODE_MASK 3
#define BCM6328_LED_MODE_ON 0
-#define BCM6328_LED_MODE_FAST 1
-#define BCM6328_LED_MODE_BLINK 2
+#define BCM6328_LED_MODE_BLINK1 1
+#define BCM6328_LED_MODE_BLINK2 2
#define BCM6328_LED_MODE_OFF 3
#define BCM6328_LED_SHIFT(X) ((X) << 1)
@@ -127,12 +132,18 @@ static void bcm6328_led_set(struct led_classdev *led_cdev,
unsigned long flags;
spin_lock_irqsave(led->lock, flags);
- *(led->blink_leds) &= ~BIT(led->pin);
+
+ /* Remove LED from cached HW blinking intervals */
+ led->blink_leds[0] &= ~BIT(led->pin);
+ led->blink_leds[1] &= ~BIT(led->pin);
+
+ /* Set LED on/off */
if ((led->active_low && value == LED_OFF) ||
(!led->active_low && value != LED_OFF))
bcm6328_led_mode(led, BCM6328_LED_MODE_ON);
else
bcm6328_led_mode(led, BCM6328_LED_MODE_OFF);
+
spin_unlock_irqrestore(led->lock, flags);
}
@@ -140,8 +151,8 @@ static unsigned long bcm6328_blink_delay(unsigned long delay)
{
unsigned long bcm6328_delay;
- bcm6328_delay = delay + BCM6328_LED_INTERVAL_MS / 2;
- bcm6328_delay = bcm6328_delay / BCM6328_LED_INTERVAL_MS;
+ bcm6328_delay = delay + BCM6328_LED_BLINK_MS / 2;
+ bcm6328_delay = bcm6328_delay / BCM6328_LED_BLINK_MS;
if (bcm6328_delay == 0)
bcm6328_delay = 1;
@@ -168,28 +179,68 @@ static int bcm6328_blink_set(struct led_classdev *led_cdev,
return -EINVAL;
}
- if (delay > BCM6328_LED_INTV_MASK) {
+ if (delay > BCM6328_LED_BLINK_MASK) {
dev_dbg(led_cdev->dev,
"fallback to soft blinking (delay > %ums)\n",
- BCM6328_LED_INTV_MASK * BCM6328_LED_INTERVAL_MS);
+ BCM6328_LED_BLINK_MASK * BCM6328_LED_BLINK_MS);
return -EINVAL;
}
spin_lock_irqsave(led->lock, flags);
- if (*(led->blink_leds) == 0 ||
- *(led->blink_leds) == BIT(led->pin) ||
- *(led->blink_delay) == delay) {
+ /*
+ * Check if any of the two configurable HW blinking intervals is
+ * available:
+ * 1. No LEDs assigned to the HW blinking interval.
+ * 2. Only this LED is assigned to the HW blinking interval.
+ * 3. LEDs with the same delay assigned.
+ */
+ if (led->blink_leds[0] == 0 ||
+ led->blink_leds[0] == BIT(led->pin) ||
+ led->blink_delay[0] == delay) {
unsigned long val;
- *(led->blink_leds) |= BIT(led->pin);
- *(led->blink_delay) = delay;
+ /* Add LED to the first HW blinking interval cache */
+ led->blink_leds[0] |= BIT(led->pin);
+
+ /* Remove LED from the second HW blinking interval cache */
+ led->blink_leds[1] &= ~BIT(led->pin);
+ /* Cache first HW blinking interval delay */
+ led->blink_delay[0] = delay;
+
+ /* Update the delay for the first HW blinking interval */
val = bcm6328_led_read(led->mem + BCM6328_REG_INIT);
- val &= ~BCM6328_LED_FAST_INTV_MASK;
- val |= (delay << BCM6328_LED_FAST_INTV_SHIFT);
+ val &= ~BCM6328_LED_BLINK1_MASK;
+ val |= (delay << BCM6328_LED_BLINK1_SHIFT);
bcm6328_led_write(led->mem + BCM6328_REG_INIT, val);
- bcm6328_led_mode(led, BCM6328_LED_MODE_BLINK);
+ /* Set the LED to first HW blinking interval */
+ bcm6328_led_mode(led, BCM6328_LED_MODE_BLINK1);
+
+ rc = 0;
+ } else if (led->blink_leds[1] == 0 ||
+ led->blink_leds[1] == BIT(led->pin) ||
+ led->blink_delay[1] == delay) {
+ unsigned long val;
+
+ /* Remove LED from the first HW blinking interval */
+ led->blink_leds[0] &= ~BIT(led->pin);
+
+ /* Add LED to the second HW blinking interval */
+ led->blink_leds[1] |= BIT(led->pin);
+
+ /* Cache second HW blinking interval delay */
+ led->blink_delay[1] = delay;
+
+ /* Update the delay for the second HW blinking interval */
+ val = bcm6328_led_read(led->mem + BCM6328_REG_INIT);
+ val &= ~BCM6328_LED_BLINK2_MASK;
+ val |= (delay << BCM6328_LED_BLINK2_SHIFT);
+ bcm6328_led_write(led->mem + BCM6328_REG_INIT, val);
+
+ /* Set the LED to second HW blinking interval */
+ bcm6328_led_mode(led, BCM6328_LED_MODE_BLINK2);
+
rc = 0;
} else {
dev_dbg(led_cdev->dev,
@@ -358,11 +409,13 @@ static int bcm6328_leds_probe(struct platform_device *pdev)
if (!lock)
return -ENOMEM;
- blink_leds = devm_kzalloc(dev, sizeof(*blink_leds), GFP_KERNEL);
+ blink_leds = devm_kcalloc(dev, BCM6328_LED_BLINK_DELAYS,
+ sizeof(*blink_leds), GFP_KERNEL);
if (!blink_leds)
return -ENOMEM;
- blink_delay = devm_kzalloc(dev, sizeof(*blink_delay), GFP_KERNEL);
+ blink_delay = devm_kcalloc(dev, BCM6328_LED_BLINK_DELAYS,
+ sizeof(*blink_delay), GFP_KERNEL);
if (!blink_delay)
return -ENOMEM;
--
2.26.2
