[PATCH v2 5/6] video: backlight: lm3533_bl: Set initial mapping mode from DT

[Svyatoslav Ryhel]

Add support to obtain the initial mapping mode from DT instead of leaving
it unconfigured. Additionally, update the linear sysfs code, which uses a
similar coding pattern.

Signed-off-by: Svyatoslav Ryhel <clamor95@xxxxxxxxx>
---
 drivers/video/backlight/lm3533_bl.c | 50 ++++++++++++++++-------------
 1 file changed, 27 insertions(+), 23 deletions(-)

diff --git a/drivers/video/backlight/lm3533_bl.c b/drivers/video/backlight/lm3533_bl.c
index 42da652df58d..c03d0d1667e4 100644
--- a/drivers/video/backlight/lm3533_bl.c
+++ b/drivers/video/backlight/lm3533_bl.c
@@ -22,6 +22,7 @@
 #define LM3533_BL_MAX_BRIGHTNESS	255
 
 #define LM3533_REG_CTRLBANK_AB_BCONF	0x1a
+#define   CTRLBANK_AB_BCONF_MODE(n)	BIT(2 * (n) + 1)
 
 
 struct lm3533_bl {
@@ -32,6 +33,7 @@ struct lm3533_bl {
 
 	u32 max_current;
 	u32 pwm;
+	bool linear;
 };
 
 
@@ -135,8 +137,9 @@ static ssize_t show_linear(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
 	struct lm3533_bl *bl = dev_get_drvdata(dev);
+	int id = lm3533_bl_get_ctrlbank_id(bl);
+	u8 mask = CTRLBANK_AB_BCONF_MODE(id);
 	u8 val;
-	u8 mask;
 	int linear;
 	int ret;
 
@@ -144,8 +147,6 @@ static ssize_t show_linear(struct device *dev,
 	if (ret)
 		return ret;
 
-	mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);
-
 	if (val & mask)
 		linear = 1;
 	else
@@ -159,23 +160,16 @@ static ssize_t store_linear(struct device *dev,
 					const char *buf, size_t len)
 {
 	struct lm3533_bl *bl = dev_get_drvdata(dev);
+	int id = lm3533_bl_get_ctrlbank_id(bl);
 	unsigned long linear;
-	u8 mask;
-	u8 val;
 	int ret;
 
 	if (kstrtoul(buf, 0, &linear))
 		return -EINVAL;
 
-	mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);
-
-	if (linear)
-		val = mask;
-	else
-		val = 0;
-
-	ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val,
-									mask);
+	ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF,
+			    linear ? CTRLBANK_AB_BCONF_MODE(id) : 0,
+			    CTRLBANK_AB_BCONF_MODE(id));
 	if (ret)
 		return ret;
 
@@ -253,8 +247,15 @@ static struct attribute_group lm3533_bl_attribute_group = {
 
 static int lm3533_bl_setup(struct lm3533_bl *bl)
 {
+	int id = lm3533_bl_get_ctrlbank_id(bl);
 	int ret;
 
+	ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF,
+			    bl->linear ? CTRLBANK_AB_BCONF_MODE(id) : 0,
+			    CTRLBANK_AB_BCONF_MODE(id));
+	if (ret)
+		return ret;
+
 	ret = lm3533_ctrlbank_set_max_current(&bl->cb, bl->max_current);
 	if (ret)
 		return ret;
@@ -317,14 +318,6 @@ static int lm3533_bl_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, bl);
 
-	ret = sysfs_create_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "failed to create sysfs attributes\n");
-		return ret;
-	}
-
-	backlight_update_status(bd);
-
 	device_property_read_u32(&pdev->dev, "led-max-microamp",
 				 &bl->max_current);
 	bl->max_current = clamp(bl->max_current, LM3533_LED_MAX_CURRENT_MIN,
@@ -333,9 +326,20 @@ static int lm3533_bl_probe(struct platform_device *pdev)
 	bl->pwm = 0;
 	device_property_read_u32(&pdev->dev, "ti,pwm-config-mask", &bl->pwm);
 
+	bl->linear = device_property_read_bool(&pdev->dev,
+					       "ti,linear-mapping-mode");
+
 	ret = lm3533_bl_setup(bl);
 	if (ret)
-		goto err_sysfs_remove;
+		return ret;
+
+	ret = sysfs_create_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to create sysfs attributes\n");
+		return ret;
+	}
+
+	backlight_update_status(bd);
 
 	ret = lm3533_ctrlbank_enable(&bl->cb);
 	if (ret)
-- 
2.51.0