From e190f57df3c7e7713687905c14e72fbcbd81c5e4 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= Date: Thu, 4 Jun 2020 15:59:05 +0200 Subject: [PATCH] leds-bcm6328: support second hw blinking interval MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: Pavel Machek --- drivers/leds/leds-bcm6328.c | 97 ++++++++++++++++++++++++++++--------- 1 file changed, 75 insertions(+), 22 deletions(-) --- 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_c 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 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_ 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, @@ -363,11 +414,13 @@ static int bcm6328_leds_probe(struct pla 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;