[PATCH v1 2/2] leds: lm3533: Support getting LED sources from DT

[Svyatoslav Ryhel <clamor95@gmail.com>]

Add support for the standard `led-sources` device tree property to
configure the mapping between control banks and physical low-voltage LED
(LVLED) outputs.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
---
 drivers/leds/leds-lm3533.c | 57 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)

diff --git a/drivers/leds/leds-lm3533.c b/drivers/leds/leds-lm3533.c
index 7db1105bee5c2..ad8bc3751e3e5 100644
--- a/drivers/leds/leds-lm3533.c
+++ b/drivers/leds/leds-lm3533.c
@@ -26,6 +26,14 @@
 #define LM3533_ALS_CHANNEL_LV_MIN	1
 #define LM3533_ALS_CHANNEL_LV_MAX	2
 
+#define LM3533_REG_OUTPUT_CONF1			0x10
+#define   OUTPUT_CONF1_SHIFT			2
+#define   OUTPUT_LVLED_MASK			0x3
+#define   OUTPUT_CONF1_PREP(x)			(((x) << OUTPUT_CONF1_SHIFT) & 0xff)
+#define LM3533_REG_OUTPUT_CONF2			0x11
+#define   OUTPUT_CONF2_SHIFT			6
+#define   OUTPUT_CONF2_PREP(x)			(((x) >> OUTPUT_CONF2_SHIFT) & 0xff)
+
 #define LM3533_REG_CTRLBANK_BCONF_BASE		0x1b
 #define LM3533_REG_PATTERN_ENABLE		0x28
 #define LM3533_REG_PATTERN_LOW_TIME_BASE	0x71
@@ -54,6 +62,9 @@ struct lm3533_led {
 	u32 max_current;
 	u32 pwm;
 
+	int num_leds;
+	u32 leds[LM3533_LVCTRLBANK_MAX];
+
 	bool have_als;
 };
 
@@ -622,8 +633,36 @@ static const struct attribute_group *lm3533_led_attribute_groups[] = {
 
 static int lm3533_led_setup(struct lm3533_led *led)
 {
+	u32 output_cfg_shift = 0;
+	u32 output_cfg_val = 0;
+	u32 output_cfg_mask = 0;
 	int ret;
 
+	for (int i = 0; i < led->num_leds; i++) {
+		if (led->leds[i] >= LM3533_LVCTRLBANK_MAX)
+			continue;
+
+		output_cfg_shift = led->leds[i] * 2;
+		output_cfg_val |= led->id << output_cfg_shift;
+		output_cfg_mask |= OUTPUT_LVLED_MASK << output_cfg_shift;
+	}
+
+	if (led->num_leds) {
+		/* LVLED1, LVLED2 and LVLED3 */
+		ret = regmap_update_bits(led->regmap, LM3533_REG_OUTPUT_CONF1,
+					 OUTPUT_CONF1_PREP(output_cfg_mask),
+					 OUTPUT_CONF1_PREP(output_cfg_val));
+		if (ret)
+			return ret;
+
+		/* LVLED4 and LVLED5 */
+		ret = regmap_update_bits(led->regmap, LM3533_REG_OUTPUT_CONF2,
+					 OUTPUT_CONF2_PREP(output_cfg_mask),
+					 OUTPUT_CONF2_PREP(output_cfg_val));
+		if (ret)
+			return ret;
+	}
+
 	ret = lm3533_ctrlbank_set_max_current(&led->cb, led->max_current);
 	if (ret)
 		return ret;
@@ -690,6 +729,24 @@ static int lm3533_led_probe(struct platform_device *pdev)
 
 	device_property_read_u32(dev, "ti,pwm-config-mask", &led->pwm);
 
+	/*
+	 * If led-sources property is not set then either this Control Bank uses
+	 * its default LVLED or is not linked to any LVLED at all.
+	 */
+	led->num_leds = device_property_count_u32(dev, "led-sources");
+	if (led->num_leds > LM3533_LVCTRLBANK_MAX)
+		return dev_err_probe(dev, -EINVAL, "Number of LED sources exceeds max %d: %d\n",
+				     LM3533_LVCTRLBANK_MAX, led->num_leds);
+
+	if (led->num_leds < 0)
+		led->num_leds = 0;
+
+	if (led->num_leds > 0) {
+		ret = device_property_read_u32_array(dev, "led-sources", led->leds, led->num_leds);
+		if (ret)
+			return dev_err_probe(dev, ret, "Failed to get led-sources\n");
+	}
+
 	ret = lm3533_led_setup(led);
 	if (ret)
 		return ret;
-- 
2.53.0