1 files changed, 239 insertions, 72 deletions

diff --git a/drivers/video/backlight/lp855x_bl.c b/drivers/video/backlight/lp855x_bl.c
index 6e4db0c874c..2ca3a040007 100644
--- a/drivers/video/backlight/lp855x_bl.c
+++ b/drivers/video/backlight/lp855x_bl.c
@@ -14,24 +14,59 @@
 #include <linux/i2c.h>
 #include <linux/backlight.h>
 #include <linux/err.h>
+#include <linux/of.h>
 #include <linux/platform_data/lp855x.h>
 #include <linux/pwm.h>
 
-/* Registers */
-#define BRIGHTNESS_CTRL		0x00
-#define DEVICE_CTRL		0x01
-#define EEPROM_START		0xA0
-#define EEPROM_END		0xA7
-#define EPROM_START		0xA0
-#define EPROM_END		0xAF
+/* LP8550/1/2/3/6 Registers */
+#define LP855X_BRIGHTNESS_CTRL		0x00
+#define LP855X_DEVICE_CTRL		0x01
+#define LP855X_EEPROM_START		0xA0
+#define LP855X_EEPROM_END		0xA7
+#define LP8556_EPROM_START		0xA0
+#define LP8556_EPROM_END		0xAF
+
+/* LP8555/7 Registers */
+#define LP8557_BL_CMD			0x00
+#define LP8557_BL_MASK			0x01
+#define LP8557_BL_ON			0x01
+#define LP8557_BL_OFF			0x00
+#define LP8557_BRIGHTNESS_CTRL		0x04
+#define LP8557_CONFIG			0x10
+#define LP8555_EPROM_START		0x10
+#define LP8555_EPROM_END		0x7A
+#define LP8557_EPROM_START		0x10
+#define LP8557_EPROM_END		0x1E
 
-#define BUF_SIZE		20
 #define DEFAULT_BL_NAME		"lcd-backlight"
 #define MAX_BRIGHTNESS		255
 
+enum lp855x_brightness_ctrl_mode {
+	PWM_BASED = 1,
+	REGISTER_BASED,
+};
+
+struct lp855x;
+
+/*
+ * struct lp855x_device_config
+ * @pre_init_device: init device function call before updating the brightness
+ * @reg_brightness: register address for brigthenss control
+ * @reg_devicectrl: register address for device control
+ * @post_init_device: late init device function call
+ */
+struct lp855x_device_config {
+	int (*pre_init_device)(struct lp855x *);
+	u8 reg_brightness;
+	u8 reg_devicectrl;
+	int (*post_init_device)(struct lp855x *);
+};
+
 struct lp855x {
 	const char *chipname;
 	enum lp855x_chip_id chip_id;
+	enum lp855x_brightness_ctrl_mode mode;
+	struct lp855x_device_config *cfg;
 	struct i2c_client *client;
 	struct backlight_device *bl;
 	struct device *dev;
@@ -39,9 +74,15 @@ struct lp855x {
 	struct pwm_device *pwm;
 };
 
-static int lp855x_read_byte(struct lp855x *lp, u8 reg, u8 *data)
+static int lp855x_write_byte(struct lp855x *lp, u8 reg, u8 data)
+{
+	return i2c_smbus_write_byte_data(lp->client, reg, data);
+}
+
+static int lp855x_update_bit(struct lp855x *lp, u8 reg, u8 mask, u8 data)
 {
 	int ret;
+	u8 tmp;
 
 	ret = i2c_smbus_read_byte_data(lp->client, reg);
 	if (ret < 0) {
@@ -49,13 +90,11 @@ static int lp855x_read_byte(struct lp855x *lp, u8 reg, u8 *data)
 		return ret;
 	}
 
-	*data = (u8)ret;
-	return 0;
-}
+	tmp = (u8)ret;
+	tmp &= ~mask;
+	tmp |= data & mask;
 
-static int lp855x_write_byte(struct lp855x *lp, u8 reg, u8 data)
-{
-	return i2c_smbus_write_byte_data(lp->client, reg, data);
+	return lp855x_write_byte(lp, reg, tmp);
 }
 
 static bool lp855x_is_valid_rom_area(struct lp855x *lp, u8 addr)
@@ -67,37 +106,105 @@ static bool lp855x_is_valid_rom_area(struct lp855x *lp, u8 addr)
 	case LP8551:
 	case LP8552:
 	case LP8553:
-		start = EEPROM_START;
-		end = EEPROM_END;
+		start = LP855X_EEPROM_START;
+		end = LP855X_EEPROM_END;
 		break;
 	case LP8556:
-		start = EPROM_START;
-		end = EPROM_END;
+		start = LP8556_EPROM_START;
+		end = LP8556_EPROM_END;
+		break;
+	case LP8555:
+		start = LP8555_EPROM_START;
+		end = LP8555_EPROM_END;
+		break;
+	case LP8557:
+		start = LP8557_EPROM_START;
+		end = LP8557_EPROM_END;
 		break;
 	default:
 		return false;
 	}
 
-	return (addr >= start && addr <= end);
+	return addr >= start && addr <= end;
+}
+
+static int lp8557_bl_off(struct lp855x *lp)
+{
+	/* BL_ON = 0 before updating EPROM settings */
+	return lp855x_update_bit(lp, LP8557_BL_CMD, LP8557_BL_MASK,
+				LP8557_BL_OFF);
+}
+
+static int lp8557_bl_on(struct lp855x *lp)
+{
+	/* BL_ON = 1 after updating EPROM settings */
+	return lp855x_update_bit(lp, LP8557_BL_CMD, LP8557_BL_MASK,
+				LP8557_BL_ON);
 }
 
-static int lp855x_init_registers(struct lp855x *lp)
+static struct lp855x_device_config lp855x_dev_cfg = {
+	.reg_brightness = LP855X_BRIGHTNESS_CTRL,
+	.reg_devicectrl = LP855X_DEVICE_CTRL,
+};
+
+static struct lp855x_device_config lp8557_dev_cfg = {
+	.reg_brightness = LP8557_BRIGHTNESS_CTRL,
+	.reg_devicectrl = LP8557_CONFIG,
+	.pre_init_device = lp8557_bl_off,
+	.post_init_device = lp8557_bl_on,
+};
+
+/*
+ * Device specific configuration flow
+ *
+ *    a) pre_init_device(optional)
+ *    b) update the brightness register
+ *    c) update device control register
+ *    d) update ROM area(optional)
+ *    e) post_init_device(optional)
+ *
+ */
+static int lp855x_configure(struct lp855x *lp)
 {
 	u8 val, addr;
 	int i, ret;
 	struct lp855x_platform_data *pd = lp->pdata;
 
+	switch (lp->chip_id) {
+	case LP8550:
+	case LP8551:
+	case LP8552:
+	case LP8553:
+	case LP8556:
+		lp->cfg = &lp855x_dev_cfg;
+		break;
+	case LP8555:
+	case LP8557:
+		lp->cfg = &lp8557_dev_cfg;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (lp->cfg->pre_init_device) {
+		ret = lp->cfg->pre_init_device(lp);
+		if (ret) {
+			dev_err(lp->dev, "pre init device err: %d\n", ret);
+			goto err;
+		}
+	}
+
 	val = pd->initial_brightness;
-	ret = lp855x_write_byte(lp, BRIGHTNESS_CTRL, val);
+	ret = lp855x_write_byte(lp, lp->cfg->reg_brightness, val);
 	if (ret)
-		return ret;
+		goto err;
 
 	val = pd->device_control;
-	ret = lp855x_write_byte(lp, DEVICE_CTRL, val);
+	ret = lp855x_write_byte(lp, lp->cfg->reg_devicectrl, val);
 	if (ret)
-		return ret;
+		goto err;
 
-	if (pd->load_new_rom_data && pd->size_program) {
+	if (pd->size_program > 0) {
 		for (i = 0; i < pd->size_program; i++) {
 			addr = pd->rom_data[i].addr;
 			val = pd->rom_data[i].val;
@@ -106,10 +213,21 @@ static int lp855x_init_registers(struct lp855x *lp)
 
 			ret = lp855x_write_byte(lp, addr, val);
 			if (ret)
-				return ret;
+				goto err;
+		}
+	}
+
+	if (lp->cfg->post_init_device) {
+		ret = lp->cfg->post_init_device(lp);
+		if (ret) {
+			dev_err(lp->dev, "post init device err: %d\n", ret);
+			goto err;
 		}
 	}
 
+	return 0;
+
+err:
 	return ret;
 }
 
@@ -138,20 +256,19 @@ static void lp855x_pwm_ctrl(struct lp855x *lp, int br, int max_br)
 static int lp855x_bl_update_status(struct backlight_device *bl)
 {
 	struct lp855x *lp = bl_get_data(bl);
-	enum lp855x_brightness_ctrl_mode mode = lp->pdata->mode;
 
-	if (bl->props.state & BL_CORE_SUSPENDED)
+	if (bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
 		bl->props.brightness = 0;
 
-	if (mode == PWM_BASED) {
+	if (lp->mode == PWM_BASED) {
 		int br = bl->props.brightness;
 		int max_br = bl->props.max_brightness;
 
 		lp855x_pwm_ctrl(lp, br, max_br);
 
-	} else if (mode == REGISTER_BASED) {
+	} else if (lp->mode == REGISTER_BASED) {
 		u8 val = bl->props.brightness;
-		lp855x_write_byte(lp, BRIGHTNESS_CTRL, val);
+		lp855x_write_byte(lp, lp->cfg->reg_brightness, val);
 	}
 
 	return 0;
@@ -159,16 +276,6 @@ static int lp855x_bl_update_status(struct backlight_device *bl)
 
 static int lp855x_bl_get_brightness(struct backlight_device *bl)
 {
-	struct lp855x *lp = bl_get_data(bl);
-	enum lp855x_brightness_ctrl_mode mode = lp->pdata->mode;
-
-	if (mode == REGISTER_BASED) {
-		u8 val = 0;
-
-		lp855x_read_byte(lp, BRIGHTNESS_CTRL, &val);
-		bl->props.brightness = val;
-	}
-
 	return bl->props.brightness;
 }
 
@@ -183,7 +290,7 @@ static int lp855x_backlight_register(struct lp855x *lp)
 	struct backlight_device *bl;
 	struct backlight_properties props;
 	struct lp855x_platform_data *pdata = lp->pdata;
-	char *name = pdata->name ? : DEFAULT_BL_NAME;
+	const char *name = pdata->name ? : DEFAULT_BL_NAME;
 
 	props.type = BACKLIGHT_PLATFORM;
 	props.max_brightness = MAX_BRIGHTNESS;
@@ -193,7 +300,7 @@ static int lp855x_backlight_register(struct lp855x *lp)
 
 	props.brightness = pdata->initial_brightness;
 
-	bl = backlight_device_register(name, lp->dev, lp,
+	bl = devm_backlight_device_register(lp->dev, name, lp->dev, lp,
 				       &lp855x_bl_ops, &props);
 	if (IS_ERR(bl))
 		return PTR_ERR(bl);
@@ -203,32 +310,25 @@ static int lp855x_backlight_register(struct lp855x *lp)
 	return 0;
 }
 
-static void lp855x_backlight_unregister(struct lp855x *lp)
-{
-	if (lp->bl)
-		backlight_device_unregister(lp->bl);
-}
-
 static ssize_t lp855x_get_chip_id(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
 	struct lp855x *lp = dev_get_drvdata(dev);
-	return scnprintf(buf, BUF_SIZE, "%s\n", lp->chipname);
+	return scnprintf(buf, PAGE_SIZE, "%s\n", lp->chipname);
 }
 
 static ssize_t lp855x_get_bl_ctl_mode(struct device *dev,
 				     struct device_attribute *attr, char *buf)
 {
 	struct lp855x *lp = dev_get_drvdata(dev);
-	enum lp855x_brightness_ctrl_mode mode = lp->pdata->mode;
 	char *strmode = NULL;
 
-	if (mode == PWM_BASED)
+	if (lp->mode == PWM_BASED)
 		strmode = "pwm based";
-	else if (mode == REGISTER_BASED)
+	else if (lp->mode == REGISTER_BASED)
 		strmode = "register based";
 
-	return scnprintf(buf, BUF_SIZE, "%s\n", strmode);
+	return scnprintf(buf, PAGE_SIZE, "%s\n", strmode);
 }
 
 static DEVICE_ATTR(chip_id, S_IRUGO, lp855x_get_chip_id, NULL);
@@ -244,16 +344,71 @@ static const struct attribute_group lp855x_attr_group = {
 	.attrs = lp855x_attributes,
 };
 
+#ifdef CONFIG_OF
+static int lp855x_parse_dt(struct device *dev, struct device_node *node)
+{
+	struct lp855x_platform_data *pdata;
+	int rom_length;
+
+	if (!node) {
+		dev_err(dev, "no platform data\n");
+		return -EINVAL;
+	}
+
+	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata)
+		return -ENOMEM;
+
+	of_property_read_string(node, "bl-name", &pdata->name);
+	of_property_read_u8(node, "dev-ctrl", &pdata->device_control);
+	of_property_read_u8(node, "init-brt", &pdata->initial_brightness);
+	of_property_read_u32(node, "pwm-period", &pdata->period_ns);
+
+	/* Fill ROM platform data if defined */
+	rom_length = of_get_child_count(node);
+	if (rom_length > 0) {
+		struct lp855x_rom_data *rom;
+		struct device_node *child;
+		int i = 0;
+
+		rom = devm_kzalloc(dev, sizeof(*rom) * rom_length, GFP_KERNEL);
+		if (!rom)
+			return -ENOMEM;
+
+		for_each_child_of_node(node, child) {
+			of_property_read_u8(child, "rom-addr", &rom[i].addr);
+			of_property_read_u8(child, "rom-val", &rom[i].val);
+			i++;
+		}
+
+		pdata->size_program = rom_length;
+		pdata->rom_data = &rom[0];
+	}
+
+	dev->platform_data = pdata;
+
+	return 0;
+}
+#else
+static int lp855x_parse_dt(struct device *dev, struct device_node *node)
+{
+	return -EINVAL;
+}
+#endif
+
 static int lp855x_probe(struct i2c_client *cl, const struct i2c_device_id *id)
 {
 	struct lp855x *lp;
-	struct lp855x_platform_data *pdata = cl->dev.platform_data;
-	enum lp855x_brightness_ctrl_mode mode;
+	struct lp855x_platform_data *pdata = dev_get_platdata(&cl->dev);
+	struct device_node *node = cl->dev.of_node;
 	int ret;
 
 	if (!pdata) {
-		dev_err(&cl->dev, "no platform data supplied\n");
-		return -EINVAL;
+		ret = lp855x_parse_dt(&cl->dev, node);
+		if (ret < 0)
+			return ret;
+
+		pdata = dev_get_platdata(&cl->dev);
 	}
 
 	if (!i2c_check_functionality(cl->adapter, I2C_FUNC_SMBUS_I2C_BLOCK))
@@ -263,7 +418,11 @@ static int lp855x_probe(struct i2c_client *cl, const struct i2c_device_id *id)
 	if (!lp)
 		return -ENOMEM;
 
-	mode = pdata->mode;
+	if (pdata->period_ns > 0)
+		lp->mode = PWM_BASED;
+	else
+		lp->mode = REGISTER_BASED;
+
 	lp->client = cl;
 	lp->dev = &cl->dev;
 	lp->pdata = pdata;
@@ -271,33 +430,27 @@ static int lp855x_probe(struct i2c_client *cl, const struct i2c_device_id *id)
 	lp->chip_id = id->driver_data;
 	i2c_set_clientdata(cl, lp);
 
-	ret = lp855x_init_registers(lp);
+	ret = lp855x_configure(lp);
 	if (ret) {
-		dev_err(lp->dev, "i2c communication err: %d", ret);
-		if (mode == REGISTER_BASED)
-			goto err_dev;
+		dev_err(lp->dev, "device config err: %d", ret);
+		return ret;
 	}
 
 	ret = lp855x_backlight_register(lp);
 	if (ret) {
 		dev_err(lp->dev,
 			"failed to register backlight. err: %d\n", ret);
-		goto err_dev;
+		return ret;
 	}
 
 	ret = sysfs_create_group(&lp->dev->kobj, &lp855x_attr_group);
 	if (ret) {
 		dev_err(lp->dev, "failed to register sysfs. err: %d\n", ret);
-		goto err_sysfs;
+		return ret;
 	}
 
 	backlight_update_status(lp->bl);
 	return 0;
-
-err_sysfs:
-	lp855x_backlight_unregister(lp);
-err_dev:
-	return ret;
 }
 
 static int lp855x_remove(struct i2c_client *cl)
@@ -307,17 +460,30 @@ static int lp855x_remove(struct i2c_client *cl)
 	lp->bl->props.brightness = 0;
 	backlight_update_status(lp->bl);
 	sysfs_remove_group(&lp->dev->kobj, &lp855x_attr_group);
-	lp855x_backlight_unregister(lp);
 
 	return 0;
 }
 
+static const struct of_device_id lp855x_dt_ids[] = {
+	{ .compatible = "ti,lp8550", },
+	{ .compatible = "ti,lp8551", },
+	{ .compatible = "ti,lp8552", },
+	{ .compatible = "ti,lp8553", },
+	{ .compatible = "ti,lp8555", },
+	{ .compatible = "ti,lp8556", },
+	{ .compatible = "ti,lp8557", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, lp855x_dt_ids);
+
 static const struct i2c_device_id lp855x_ids[] = {
 	{"lp8550", LP8550},
 	{"lp8551", LP8551},
 	{"lp8552", LP8552},
 	{"lp8553", LP8553},
+	{"lp8555", LP8555},
 	{"lp8556", LP8556},
+	{"lp8557", LP8557},
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, lp855x_ids);
@@ -325,6 +491,7 @@ MODULE_DEVICE_TABLE(i2c, lp855x_ids);
 static struct i2c_driver lp855x_driver = {
 	.driver = {
 		   .name = "lp855x",
+		   .of_match_table = of_match_ptr(lp855x_dt_ids),
 		   },
 	.probe = lp855x_probe,
 	.remove = lp855x_remove,