[PATCH v3 2/4] regulator: adapt fixed regulator driver to dt

[Rajendra Nayak <rnayak-l0cyMroinI0@public.gmane.org>]

The fixed regulator driver uses of_get_fixed_voltage_config()
to extract fixed_voltage_config structure contents from device tree.

Also add documenation for additional bindings for fixed
regulators that can be passed through dt.

Signed-off-by: Rajendra Nayak <rnayak-l0cyMroinI0@public.gmane.org>
---
 .../bindings/regulator/fixed-regulator.txt         |   25 +++++++++
 drivers/regulator/fixed.c                          |   57 ++++++++++++++++++++
 2 files changed, 82 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/regulator/fixed-regulator.txt

diff --git a/Documentation/devicetree/bindings/regulator/fixed-regulator.txt b/Documentation/devicetree/bindings/regulator/fixed-regulator.txt
new file mode 100644
index 0000000..049df3d
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/fixed-regulator.txt
@@ -0,0 +1,25 @@
+Fixed Voltage regulators
+
+Required properties:
+- compatible: Must be "regulator-fixed";
+
+Optional properties:
+- regulator-fixed-supply: Name of the regulator supply
+- regulator-fixed-microvolts: Output voltage of regulator
+- regulator-fixed-gpio: gpio to use for enable control
+- regulator-fixed-startup-delay: startup time in microseconds
+- regulator-fixed-enable-high: Polarity of enable GPIO,
+  1 = Active High, 0 = Active low
+- regulator-fixed-enabled-at-boot: 1 = yes, 0 = no
+
+Example:
+
+	abc: fixedregulator@0 {
+		compatible = "regulator-fixed";
+		regulator-fixed-supply = "fixed-supply";
+		regulator-fixed-microvolts = <1800000>;
+		regulator-fixed-gpio = <43>;
+		regulator-fixed-startup-delay = <70000>;
+		regulator-fixed-enable-high;
+		regulator-fixed-enabled-at-boot;
+	};
diff --git a/drivers/regulator/fixed.c b/drivers/regulator/fixed.c
index 2fe9d99..9851b42 100644
--- a/drivers/regulator/fixed.c
+++ b/drivers/regulator/fixed.c
@@ -26,6 +26,9 @@
 #include <linux/gpio.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/regulator/machine.h>
 
 struct fixed_voltage_data {
 	struct regulator_desc desc;
@@ -37,6 +40,46 @@ struct fixed_voltage_data {
 	bool is_enabled;
 };
 
+
+/**
+ * of_get_fixed_voltage_config - extract fixed_voltage_config structure info
+ * @dev: device requesting for fixed_voltage_config
+ *
+ * Populates fixed_voltage_config structure by extracting data from device
+ * tree node, returns a pointer to the populated structure of NULL if memory
+ * alloc fails.
+ */
+struct fixed_voltage_config *of_get_fixed_voltage_config(struct device *dev)
+{
+	struct fixed_voltage_config *config;
+	struct device_node *np = dev->of_node;
+	const __be32 *microvolts, *gpio, *delay;
+
+	config = devm_kzalloc(dev, sizeof(struct fixed_voltage_config), GFP_KERNEL);
+	if (!config)
+		return NULL;
+
+	config->supply_name = of_get_property(np, "regulator-fixed-supply", NULL);
+	microvolts = of_get_property(np, "regulator-fixed-microvolts", NULL);
+	if (microvolts)
+		config->microvolts = be32_to_cpu(*microvolts);
+	gpio = of_get_property(np, "regulator-fixed-gpio", NULL);
+	if (gpio)
+		config->gpio = be32_to_cpu(*gpio);
+	delay = of_get_property(np, "regulator-fixed-startup-delay", NULL);
+	if (delay)
+		config->startup_delay = be32_to_cpu(*delay);
+
+	if (of_find_property(np, "regulator-fixed-enable-high", NULL))
+		config->enable_high = true;
+	if (of_find_property(np, "regulator-fixed-enabled-at-boot", NULL))
+		config->enabled_at_boot = true;
+
+	config->init_data = of_get_regulator_init_data(dev);
+
+	return config;
+}
+
 static int fixed_voltage_is_enabled(struct regulator_dev *dev)
 {
 	struct fixed_voltage_data *data = rdev_get_drvdata(dev);
@@ -108,6 +151,9 @@ static int __devinit reg_fixed_voltage_probe(struct platform_device *pdev)
 	struct fixed_voltage_data *drvdata;
 	int ret;
 
+	if (pdev->dev.of_node)
+		config = of_get_fixed_voltage_config(&pdev->dev);
+
 	drvdata = kzalloc(sizeof(struct fixed_voltage_data), GFP_KERNEL);
 	if (drvdata == NULL) {
 		dev_err(&pdev->dev, "Failed to allocate device data\n");
@@ -216,12 +262,23 @@ static int __devexit reg_fixed_voltage_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#if defined(CONFIG_OF)
+static const struct of_device_id fixed_of_match[] __devinitconst = {
+	{ .compatible = "regulator-fixed", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, fixed_of_match);
+#else
+#define fixed_of_match NULL
+#endif
+
 static struct platform_driver regulator_fixed_voltage_driver = {
 	.probe		= reg_fixed_voltage_probe,
 	.remove		= __devexit_p(reg_fixed_voltage_remove),
 	.driver		= {
 		.name		= "reg-fixed-voltage",
 		.owner		= THIS_MODULE,
+		.of_match_table = fixed_of_match,
 	},
 };
 
-- 
1.7.1