regulator: adapt fixed regulator driver to dt
Rajendra Nayak [Fri, 18 Nov 2011 11:17:18 +0000 (16:17 +0530)]
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@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

Documentation/devicetree/bindings/regulator/fixed-regulator.txt [new file with mode: 0644]
drivers/regulator/fixed.c

diff --git a/Documentation/devicetree/bindings/regulator/fixed-regulator.txt b/Documentation/devicetree/bindings/regulator/fixed-regulator.txt
new file mode 100644 (file)
index 0000000..9cf57fd
--- /dev/null
@@ -0,0 +1,29 @@
+Fixed Voltage regulators
+
+Required properties:
+- compatible: Must be "regulator-fixed";
+
+Optional properties:
+- gpio: gpio to use for enable control
+- startup-delay-us: startup time in microseconds
+- enable-active-high: Polarity of GPIO is Active high
+If this property is missing, the default assumed is Active low.
+
+Any property defined as part of the core regulator
+binding, defined in regulator.txt, can also be used.
+However a fixed voltage regulator is expected to have the
+regulator-min-microvolt and regulator-max-microvolt
+to be the same.
+
+Example:
+
+       abc: fixedregulator@0 {
+               compatible = "regulator-fixed";
+               regulator-name = "fixed-supply";
+               regulator-min-microvolt = <1800000>;
+               regulator-max-microvolt = <1800000>;
+               gpio = <&gpio1 16 0>;
+               startup-delay-us = <70000>;
+               enable-active-high;
+               regulator-boot-on
+       };
index 21ecf21..0650856 100644 (file)
 #include <linux/gpio.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/regulator/machine.h>
 
 struct fixed_voltage_data {
        struct regulator_desc desc;
@@ -38,6 +42,53 @@ 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 *delay;
+       struct regulator_init_data *init_data;
+
+       config = devm_kzalloc(dev, sizeof(struct fixed_voltage_config),
+                                                                GFP_KERNEL);
+       if (!config)
+               return NULL;
+
+       config->init_data = of_get_regulator_init_data(dev);
+       init_data = config->init_data;
+
+       config->supply_name = init_data->constraints.name;
+       if (init_data->constraints.min_uV == init_data->constraints.max_uV) {
+               config->microvolts = init_data->constraints.min_uV;
+       } else {
+               dev_err(dev,
+                        "Fixed regulator specified with variable voltages\n");
+               return NULL;
+       }
+
+       if (init_data->constraints.boot_on)
+               config->enabled_at_boot = true;
+
+       config->gpio = of_get_named_gpio(np, "gpio", 0);
+       delay = of_get_property(np, "startup-delay-us", NULL);
+       if (delay)
+               config->startup_delay = be32_to_cpu(*delay);
+
+       if (of_find_property(np, "enable-active-high", NULL))
+               config->enable_high = true;
+
+       return config;
+}
+
 static int fixed_voltage_is_enabled(struct regulator_dev *dev)
 {
        struct fixed_voltage_data *data = rdev_get_drvdata(dev);
@@ -109,6 +160,9 @@ 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");
@@ -217,12 +271,23 @@ 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,
        },
 };