[PATCH v2] mfd: as3711: add OF support

[Guennadi Liakhovetski <g.liakhovetski@gmx.de>]

Add device-tree bindings to the AS3711 regulator and backlight drivers.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---

v2:
1. remove of_device_is_available() - it breaks compilation with CONFIG_OF 
disabled and is redundant anyway - I2C devices are only registered for 
available devoces
2. add parenthesis to eliminate a compiler warning

 Documentation/devicetree/bindings/mfd/as3711.txt |   73 +++++++++++++
 drivers/mfd/as3711.c                             |   27 ++++-
 drivers/regulator/as3711-regulator.c             |   69 ++++++++++++-
 drivers/video/backlight/as3711_bl.c              |  118 +++++++++++++++++++++-
 4 files changed, 279 insertions(+), 8 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/mfd/as3711.txt

diff --git a/Documentation/devicetree/bindings/mfd/as3711.txt b/Documentation/devicetree/bindings/mfd/as3711.txt
new file mode 100644
index 0000000..d98cf18
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/as3711.txt
@@ -0,0 +1,73 @@
+AS3711 is an I2C PMIC from Austria MicroSystems with multiple DCDC and LDO power
+supplies, a battery charger and an RTC. So far only bindings for the two stepup
+DCDC converters are defined. Other DCDC and LDO supplies are configured, using
+standard regulator properties, they must belong to a sub-node, called
+"regulators" and be called "sd1" to "sd4" and "ldo1" to "ldo8." Stepup converter
+configuration should be placed in a subnode, called "backlight."
+
+Compulsory properties:
+- compatible		: must be "ams,as3711"
+- reg			: specifies the I2C address
+
+To use the SU1 converter as a backlight source the following two properties must
+be provided:
+- su1-dev		: framebuffer phandle
+- su1-max-uA		: maximum current
+
+To use the SU2 converter as a backlight source the following two properties must
+be provided:
+- su2-dev		: framebuffer phandle
+- su1-max-uA		: maximum current
+
+Additionally one of these properties must be provided to select the type of
+feedback used:
+- su2-feedback-voltage	: voltage feedback is used
+- su2-feedback-curr1	: CURR1 input used for current feedback
+- su2-feedback-curr2	: CURR2 input used for current feedback
+- su2-feedback-curr3	: CURR3 input used for current feedback
+- su2-feedback-curr-auto: automatic current feedback selection
+
+and one of these to select the over-voltage protection pin
+- su2-fbprot-lx-sd4	: LX_SD4 is used for over-voltage protection
+- su2-fbprot-gpio2	: GPIO2 is used for over-voltage protection
+- su2-fbprot-gpio3	: GPIO3 is used for over-voltage protection
+- su2-fbprot-gpio4	: GPIO4 is used for over-voltage protection
+
+If "su2-feedback-curr-auto" is selected, one or more of the following properties
+have to be specified:
+- su2-auto-curr1	: use CURR1 input for current feedback
+- su2-auto-curr2	: use CURR2 input for current feedback
+- su2-auto-curr3	: use CURR3 input for current feedback
+
+Example:
+
+as3711@40 {
+	compatible = "ams,as3711";
+	reg = <0x40>;
+
+	regulators {
+		sd4 {
+			regulator-name = "1.215V";
+			regulator-min-microvolt = <1215000>;
+			regulator-max-microvolt = <1235000>;
+		};
+		ldo2 {
+			regulator-name = "2.8V CPU";
+			regulator-min-microvolt = <2800000>;
+			regulator-max-microvolt = <2800000>;
+			regulator-always-on;
+			regulator-boot-on;
+		};
+	};
+
+	backlight {
+		compatible = "ams,as3711-bl";
+		su2-dev = <&lcdc>;
+		su2-max-uA = <36000>;
+		su2-feedback-curr-auto;
+		su2-fbprot-gpio4;
+		su2-auto-curr1;
+		su2-auto-curr2;
+		su2-auto-curr3;
+	};
+};
diff --git a/drivers/mfd/as3711.c b/drivers/mfd/as3711.c
index e994c96..01e4141 100644
--- a/drivers/mfd/as3711.c
+++ b/drivers/mfd/as3711.c
@@ -112,16 +112,34 @@ static const struct regmap_config as3711_regmap_config = {
 	.cache_type = REGCACHE_RBTREE,
 };
 
+#ifdef CONFIG_OF
+static struct of_device_id as3711_of_match[] = {
+	{.compatible = "ams,as3711",},
+	{}
+};
+MODULE_DEVICE_TABLE(of, as3711_of_match);
+#endif
+
 static int as3711_i2c_probe(struct i2c_client *client,
 			    const struct i2c_device_id *id)
 {
 	struct as3711 *as3711;
-	struct as3711_platform_data *pdata = client->dev.platform_data;
+	struct as3711_platform_data *pdata;
 	unsigned int id1, id2;
 	int ret;
 
-	if (!pdata)
-		dev_dbg(&client->dev, "Platform data not found\n");
+	if (!client->dev.of_node) {
+		pdata = client->dev.platform_data;
+		if (!pdata)
+			dev_dbg(&client->dev, "Platform data not found\n");
+	} else {
+		pdata = devm_kzalloc(&client->dev,
+				     sizeof(*pdata), GFP_KERNEL);
+		if (!pdata) {
+			dev_err(&client->dev, "Failed to allocate pdata\n");
+			return -ENOMEM;
+		}
+	}
 
 	as3711 = devm_kzalloc(&client->dev, sizeof(struct as3711), GFP_KERNEL);
 	if (!as3711) {
@@ -193,7 +211,8 @@ static struct i2c_driver as3711_i2c_driver = {
 	.driver = {
 		   .name = "as3711",
 		   .owner = THIS_MODULE,
-		   },
+		   .of_match_table = of_match_ptr(as3711_of_match),
+	},
 	.probe = as3711_i2c_probe,
 	.remove = as3711_i2c_remove,
 	.id_table = as3711_i2c_id,
diff --git a/drivers/regulator/as3711-regulator.c b/drivers/regulator/as3711-regulator.c
index f0ba8c4..cf145fc 100644
--- a/drivers/regulator/as3711-regulator.c
+++ b/drivers/regulator/as3711-regulator.c
@@ -13,9 +13,11 @@
 #include <linux/init.h>
 #include <linux/mfd/as3711.h>
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
 #include <linux/regulator/driver.h>
+#include <linux/regulator/of_regulator.h>
 #include <linux/slab.h>
 
 struct as3711_regulator_info {
@@ -276,6 +278,57 @@ static struct as3711_regulator_info as3711_reg_info[] = {
 
 #define AS3711_REGULATOR_NUM ARRAY_SIZE(as3711_reg_info)
 
+static const char *as3711_regulator_of_names[AS3711_REGULATOR_NUM] = {
+	[AS3711_REGULATOR_SD_1] = "sd1",
+	[AS3711_REGULATOR_SD_2] = "sd2",
+	[AS3711_REGULATOR_SD_3] = "sd3",
+	[AS3711_REGULATOR_SD_4] = "sd4",
+	[AS3711_REGULATOR_LDO_1] = "ldo1",
+	[AS3711_REGULATOR_LDO_2] = "ldo2",
+	[AS3711_REGULATOR_LDO_3] = "ldo3",
+	[AS3711_REGULATOR_LDO_4] = "ldo4",
+	[AS3711_REGULATOR_LDO_5] = "ldo5",
+	[AS3711_REGULATOR_LDO_6] = "ldo6",
+	[AS3711_REGULATOR_LDO_7] = "ldo7",
+	[AS3711_REGULATOR_LDO_8] = "ldo8",
+};
+
+static int as3711_regulator_parse_dt(struct device *dev)
+{
+	struct as3711_regulator_pdata *pdata = dev_get_platdata(dev);
+	struct device_node *regulators =
+		of_find_node_by_name(dev->parent->of_node, "regulators");
+	struct of_regulator_match *matches, *match;
+	const int count = AS3711_REGULATOR_NUM;
+	int ret, i;
+
+	if (!regulators) {
+		dev_err(dev, "regulator node not found\n");
+		return -ENODEV;
+	}
+
+	matches = devm_kzalloc(dev, sizeof(*matches) * count, GFP_KERNEL);
+	if (!matches)
+		return -ENOMEM;
+
+	for (i = 0, match = matches; i < count; i++, match++) {
+		match->name = as3711_regulator_of_names[i];
+		match->driver_data = as3711_reg_info + i;
+	}
+
+	ret = of_regulator_match(dev->parent, regulators, matches, count);
+	if (ret < 0) {
+		dev_err(dev, "Error parsing regulator init data: %d\n", ret);
+		return ret;
+	}
+
+	for (i = 0, match = matches; i < count; i++, match++)
+		if (match->of_node)
+			pdata->init_data[i] = match->init_data;
+
+	return 0;
+}
+
 static int as3711_regulator_probe(struct platform_device *pdev)
 {
 	struct as3711_regulator_pdata *pdata = dev_get_platdata(&pdev->dev);
@@ -289,8 +342,18 @@ static int as3711_regulator_probe(struct platform_device *pdev)
 	int ret;
 	int id;
 
-	if (!pdata)
-		dev_dbg(&pdev->dev, "No platform data...\n");
+	if (!pdata) {
+		dev_err(&pdev->dev, "No platform data...\n");
+		return -ENODEV;
+	}
+
+	if (pdev->dev.parent->of_node) {
+		ret = as3711_regulator_parse_dt(&pdev->dev);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "DT parsing failed: %d\n", ret);
+			return ret;
+		}
+	}
 
 	regs = devm_kzalloc(&pdev->dev, AS3711_REGULATOR_NUM *
 			sizeof(struct as3711_regulator), GFP_KERNEL);
@@ -300,7 +363,7 @@ static int as3711_regulator_probe(struct platform_device *pdev)
 	}
 
 	for (id = 0, ri = as3711_reg_info; id < AS3711_REGULATOR_NUM; ++id, ri++) {
-		reg_data = pdata ? pdata->init_data[id] : NULL;
+		reg_data = pdata->init_data[id];
 
 		/* No need to register if there is no regulator data */
 		if (!reg_data)
diff --git a/drivers/video/backlight/as3711_bl.c b/drivers/video/backlight/as3711_bl.c
index c6bc65d..c78e4cb 100644
--- a/drivers/video/backlight/as3711_bl.c
+++ b/drivers/video/backlight/as3711_bl.c
@@ -257,6 +257,109 @@ static int as3711_bl_register(struct platform_device *pdev,
 	return 0;
 }
 
+static int as3711_backlight_parse_dt(struct device *dev)
+{
+	struct as3711_bl_pdata *pdata = dev_get_platdata(dev);
+	struct device_node *bl =
+		of_find_node_by_name(dev->parent->of_node, "backlight"), *fb;
+	int ret;
+
+	if (!bl) {
+		dev_dbg(dev, "backlight node not found\n");
+		return -ENODEV;
+	}
+
+	fb = of_parse_phandle(bl, "su1-dev", 0);
+	if (fb) {
+		pdata->su1_fb = fb->full_name;
+
+		ret = of_property_read_u32(bl, "su1-max-uA", &pdata->su1_max_uA);
+		if (pdata->su1_max_uA <= 0)
+			ret = -EINVAL;
+		if (ret < 0)
+			return ret;
+	}
+
+	fb = of_parse_phandle(bl, "su2-dev", 0);
+	if (fb) {
+		int count = 0;
+
+		pdata->su2_fb = fb->full_name;
+
+		ret = of_property_read_u32(bl, "su2-max-uA", &pdata->su2_max_uA);
+		if (pdata->su2_max_uA <= 0)
+			ret = -EINVAL;
+		if (ret < 0)
+			return ret;
+
+		if (of_find_property(bl, "su2-feedback-voltage", NULL)) {
+			pdata->su2_feedback = AS3711_SU2_VOLTAGE;
+			count++;
+		}
+		if (of_find_property(bl, "su2-feedback-curr1", NULL)) {
+			pdata->su2_feedback = AS3711_SU2_CURR1;
+			count++;
+		}
+		if (of_find_property(bl, "su2-feedback-curr2", NULL)) {
+			pdata->su2_feedback = AS3711_SU2_CURR2;
+			count++;
+		}
+		if (of_find_property(bl, "su2-feedback-curr3", NULL)) {
+			pdata->su2_feedback = AS3711_SU2_CURR3;
+			count++;
+		}
+		if (of_find_property(bl, "su2-feedback-curr-auto", NULL)) {
+			pdata->su2_feedback = AS3711_SU2_CURR_AUTO;
+			count++;
+		}
+		if (count != 1)
+			return -EINVAL;
+
+		count = 0;
+		if (of_find_property(bl, "su2-fbprot-lx-sd4", NULL)) {
+			pdata->su2_fbprot = AS3711_SU2_LX_SD4;
+			count++;
+		}
+		if (of_find_property(bl, "su2-fbprot-gpio2", NULL)) {
+			pdata->su2_fbprot = AS3711_SU2_GPIO2;
+			count++;
+		}
+		if (of_find_property(bl, "su2-fbprot-gpio3", NULL)) {
+			pdata->su2_fbprot = AS3711_SU2_GPIO3;
+			count++;
+		}
+		if (of_find_property(bl, "su2-fbprot-gpio4", NULL)) {
+			pdata->su2_fbprot = AS3711_SU2_GPIO4;
+			count++;
+		}
+		if (count != 1)
+			return -EINVAL;
+
+		count = 0;
+		if (of_find_property(bl, "su2-auto-curr1", NULL)) {
+			pdata->su2_auto_curr1 = true;
+			count++;
+		}
+		if (of_find_property(bl, "su2-auto-curr2", NULL)) {
+			pdata->su2_auto_curr2 = true;
+			count++;
+		}
+		if (of_find_property(bl, "su2-auto-curr3", NULL)) {
+			pdata->su2_auto_curr3 = true;
+			count++;
+		}
+
+		/*
+		 * At least one su2-auto-curr* must be specified iff
+		 * AS3711_SU2_CURR_AUTO is used
+		 */
+		if (!count ^ (pdata->su2_feedback != AS3711_SU2_CURR_AUTO))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int as3711_backlight_probe(struct platform_device *pdev)
 {
 	struct as3711_bl_pdata *pdata = dev_get_platdata(&pdev->dev);
@@ -266,11 +369,24 @@ static int as3711_backlight_probe(struct platform_device *pdev)
 	unsigned int max_brightness;
 	int ret;
 
-	if (!pdata || (!pdata->su1_fb && !pdata->su2_fb)) {
+	if (!pdata) {
 		dev_err(&pdev->dev, "No platform data, exiting...\n");
 		return -ENODEV;
 	}
 
+	if (pdev->dev.parent->of_node) {
+		ret = as3711_backlight_parse_dt(&pdev->dev);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "DT parsing failed: %d\n", ret);
+			return ret;
+		}
+	}
+
+	if (!pdata->su1_fb && !pdata->su2_fb) {
+		dev_err(&pdev->dev, "No framebuffer specified\n");
+		return -EINVAL;
+	}
+
 	/*
 	 * Due to possible hardware damage I chose to block all modes,
 	 * unsupported on my hardware. Anyone, wishing to use any of those modes
-- 
1.7.2.5