leds-bcm6328: support second hw blinking interval

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@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

diff --git a/drivers/leds/leds-bcm6328.c b/drivers/leds/leds-bcm6328.c
index 42e1b75..bad7efb 100644 (file)
--- 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;