[PATCH v5 2/2] leds: sc27xx: Add pattern_set/get/clear interfaces for LED controller

[Baolin Wang <baolin.wang@linaro.org>]

This patch implements the 'pattern_set', 'pattern_get' and 'pattern_clear'
interfaces to support SC27XX LED breathing mode.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
Changes from v4:
 - None.

Changes from v3:
 - None.

Changes from v2:
 - No updates.

Changes from v1:
 - No updates.
---
 drivers/leds/leds-sc27xx-bltc.c |  160 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 160 insertions(+)

diff --git a/drivers/leds/leds-sc27xx-bltc.c b/drivers/leds/leds-sc27xx-bltc.c
index 9d9b7aa..898f92d 100644
--- a/drivers/leds/leds-sc27xx-bltc.c
+++ b/drivers/leds/leds-sc27xx-bltc.c
@@ -6,6 +6,7 @@
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
+#include <linux/slab.h>
 #include <uapi/linux/uleds.h>
 
 /* PMIC global control register definition */
@@ -32,8 +33,13 @@
 #define SC27XX_DUTY_MASK	GENMASK(15, 0)
 #define SC27XX_MOD_MASK		GENMASK(7, 0)
 
+#define SC27XX_CURVE_SHIFT	8
+#define SC27XX_CURVE_L_MASK	GENMASK(7, 0)
+#define SC27XX_CURVE_H_MASK	GENMASK(15, 8)
+
 #define SC27XX_LEDS_OFFSET	0x10
 #define SC27XX_LEDS_MAX		3
+#define SC27XX_LEDS_PATTERN_CNT	4
 
 struct sc27xx_led {
 	char name[LED_MAX_NAME_SIZE];
@@ -122,6 +128,157 @@ static int sc27xx_led_set(struct led_classdev *ldev, enum led_brightness value)
 	return err;
 }
 
+static int sc27xx_led_pattern_clear(struct led_classdev *ldev)
+{
+	struct sc27xx_led *leds = to_sc27xx_led(ldev);
+	struct regmap *regmap = leds->priv->regmap;
+	u32 base = sc27xx_led_get_offset(leds);
+	u32 ctrl_base = leds->priv->base + SC27XX_LEDS_CTRL;
+	u8 ctrl_shift = SC27XX_CTRL_SHIFT * leds->line;
+	int err;
+
+	mutex_lock(&leds->priv->lock);
+
+	/* Reset the rise, high, fall and low time to zero. */
+	regmap_write(regmap, base + SC27XX_LEDS_CURVE0, 0);
+	regmap_write(regmap, base + SC27XX_LEDS_CURVE1, 0);
+
+	err = regmap_update_bits(regmap, ctrl_base,
+			(SC27XX_LED_RUN | SC27XX_LED_TYPE) << ctrl_shift, 0);
+
+	mutex_unlock(&leds->priv->lock);
+
+	return err;
+}
+
+static int sc27xx_led_pattern_set(struct led_classdev *ldev,
+				  struct led_pattern *pattern,
+				  int len)
+{
+	struct sc27xx_led *leds = to_sc27xx_led(ldev);
+	u32 base = sc27xx_led_get_offset(leds);
+	u32 ctrl_base = leds->priv->base + SC27XX_LEDS_CTRL;
+	u8 ctrl_shift = SC27XX_CTRL_SHIFT * leds->line;
+	struct regmap *regmap = leds->priv->regmap;
+	int err;
+
+	/*
+	 * Must contain 4 patterns to configure the rise time, high time, fall
+	 * time and low time to enable the breathing mode.
+	 */
+	if (len != SC27XX_LEDS_PATTERN_CNT)
+		return -EINVAL;
+
+	mutex_lock(&leds->priv->lock);
+
+	err = regmap_update_bits(regmap, base + SC27XX_LEDS_CURVE0,
+				 SC27XX_CURVE_L_MASK, pattern[0].delta_t);
+	if (err)
+		goto out;
+
+	err = regmap_update_bits(regmap, base + SC27XX_LEDS_CURVE1,
+				 SC27XX_CURVE_L_MASK, pattern[1].delta_t);
+	if (err)
+		goto out;
+
+	err = regmap_update_bits(regmap, base + SC27XX_LEDS_CURVE0,
+				 SC27XX_CURVE_H_MASK,
+				 pattern[2].delta_t << SC27XX_CURVE_SHIFT);
+	if (err)
+		goto out;
+
+
+	err = regmap_update_bits(regmap, base + SC27XX_LEDS_CURVE1,
+				 SC27XX_CURVE_H_MASK,
+				 pattern[3].delta_t << SC27XX_CURVE_SHIFT);
+	if (err)
+		goto out;
+
+
+	err = regmap_update_bits(regmap, base + SC27XX_LEDS_DUTY,
+				 SC27XX_DUTY_MASK,
+				 (pattern[0].brightness << SC27XX_DUTY_SHIFT) |
+				 SC27XX_MOD_MASK);
+	if (err)
+		goto out;
+
+	/* Enable the LED breathing mode */
+	err = regmap_update_bits(regmap, ctrl_base,
+				 SC27XX_LED_RUN << ctrl_shift,
+				 SC27XX_LED_RUN << ctrl_shift);
+
+out:
+	mutex_unlock(&leds->priv->lock);
+
+	return err;
+}
+
+static struct led_pattern *sc27xx_led_pattern_get(struct led_classdev *ldev,
+						  int *len)
+{
+	struct sc27xx_led *leds = to_sc27xx_led(ldev);
+	u32 base = sc27xx_led_get_offset(leds);
+	struct regmap *regmap = leds->priv->regmap;
+	struct led_pattern *pattern;
+	int i, err;
+	u32 val;
+
+	/*
+	 * Must allocate 4 patterns to show the rise time, high time, fall time
+	 * and low time.
+	 */
+	pattern = kcalloc(SC27XX_LEDS_PATTERN_CNT, sizeof(*pattern),
+			  GFP_KERNEL);
+	if (!pattern)
+		return ERR_PTR(-ENOMEM);
+
+	mutex_lock(&leds->priv->lock);
+
+	err = regmap_read(regmap, base + SC27XX_LEDS_CURVE0, &val);
+	if (err)
+		goto out;
+
+	pattern[0].delta_t = val & SC27XX_CURVE_L_MASK;
+
+	err = regmap_read(regmap, base + SC27XX_LEDS_CURVE1, &val);
+	if (err)
+		goto out;
+
+	pattern[1].delta_t = val & SC27XX_CURVE_L_MASK;
+
+	err = regmap_read(regmap, base + SC27XX_LEDS_CURVE0, &val);
+	if (err)
+		goto out;
+
+	pattern[2].delta_t = (val & SC27XX_CURVE_H_MASK) >> SC27XX_CURVE_SHIFT;
+
+	err = regmap_read(regmap, base + SC27XX_LEDS_CURVE1, &val);
+	if (err)
+		goto out;
+
+	pattern[3].delta_t = (val & SC27XX_CURVE_H_MASK) >> SC27XX_CURVE_SHIFT;
+
+	err = regmap_read(regmap, base + SC27XX_LEDS_DUTY, &val);
+	if (err)
+		goto out;
+
+	mutex_unlock(&leds->priv->lock);
+
+	val = (val & SC27XX_DUTY_MASK) >> SC27XX_DUTY_SHIFT;
+	for (i = 0; i < SC27XX_LEDS_PATTERN_CNT; i++)
+		pattern[i].brightness = val;
+
+	*len = SC27XX_LEDS_PATTERN_CNT;
+
+	return pattern;
+
+out:
+	mutex_unlock(&leds->priv->lock);
+	kfree(pattern);
+
+	return ERR_PTR(err);
+}
+
 static int sc27xx_led_register(struct device *dev, struct sc27xx_led_priv *priv)
 {
 	int i, err;
@@ -140,6 +297,9 @@ static int sc27xx_led_register(struct device *dev, struct sc27xx_led_priv *priv)
 		led->priv = priv;
 		led->ldev.name = led->name;
 		led->ldev.brightness_set_blocking = sc27xx_led_set;
+		led->ldev.pattern_set = sc27xx_led_pattern_set;
+		led->ldev.pattern_get = sc27xx_led_pattern_get;
+		led->ldev.pattern_clear = sc27xx_led_pattern_clear;
 
 		err = devm_led_classdev_register(dev, &led->ldev);
 		if (err)
-- 
1.7.9.5