[PATCH] regulator: gpio-regulator: add DT bindings
Daniel Mack
zonque at gmail.com
Mon Sep 10 23:41:44 EST 2012
Add DT bindings for the gpio-regulator driver and some documentation on
how to use it.
Signed-off-by: Daniel Mack <zonque at gmail.com>
---
.../bindings/regulator/gpio-regulator.txt | 58 ++++++++++
drivers/regulator/gpio-regulator.c | 118 ++++++++++++++++++++-
2 files changed, 175 insertions(+), 1 deletion(-)
create mode 100644 Documentation/devicetree/bindings/regulator/gpio-regulator.txt
diff --git a/Documentation/devicetree/bindings/regulator/gpio-regulator.txt b/Documentation/devicetree/bindings/regulator/gpio-regulator.txt
new file mode 100644
index 0000000..ea3eb09
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/gpio-regulator.txt
@@ -0,0 +1,58 @@
+Device tree bindings for GPIO controlled voltages
+
+Voltage or current regulators on boards that are controlled by GPIOs can
+be used by the gpio-regulator driver.
+
+Required properties:
+
+ - "compatible": must be set to "gpio-regulator"
+ - "regulator-name": must be set to a string describing the name of this
+ regulator.
+
+Optional properties:
+
+ - "startup-delay": Start-up time in microseconds
+ - "enable-high": Polarity of enable GPIO. Active high if
+ defined, otherwise active low
+ - "enabled-at-boot": If set, the regulator has been enabled at boot
+ time
+ - "regulator-type-voltage": The regulator controls a voltage
+ - "regulator-type-current": The regulator controls a current
+ - "states": An array of possible states, describing the
+ GPIO states to reach a given value
+ - "value": The value of the state, in microvolts or
+ microamperes
+ - "gpios": bitfield of gpio target-states for the value
+ The n-th bit in the bitfield describes the
+ state of the n-th GPIO from the gpios-array
+
+Also, all properties described in
+Documentation/devicetree/bindings/regulator/regulator.txt are supported as
+well.
+
+Example:
+
+ reg_gpio {
+ compatible = "gpio-regulator";
+ regulator-name = "voltage";
+ regulator-enable-high;
+ regulator-type-voltage;
+ regulator-min-microvolt = <3300000>;
+ regulator-max-microvolt = <3300000>;
+ regulator-always-on;
+
+ gpios = <&gpio 23 0>;
+
+ states {
+ state-on {
+ value = <3300000>;
+ gpios = <0x1>;
+ };
+
+ state-off {
+ value = <0>;
+ gpios = <0x0>;
+ };
+ };
+ };
+
diff --git a/drivers/regulator/gpio-regulator.c b/drivers/regulator/gpio-regulator.c
index 8b5944f..c44edd0 100644
--- a/drivers/regulator/gpio-regulator.c
+++ b/drivers/regulator/gpio-regulator.c
@@ -25,10 +25,14 @@
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/gpio-regulator.h>
+#include <linux/regulator/of_regulator.h>
#include <linux/gpio.h>
#include <linux/slab.h>
@@ -134,13 +138,124 @@ static struct regulator_ops gpio_regulator_current_ops = {
.set_current_limit = gpio_regulator_set_current_limit,
};
+#ifdef CONFIG_OF
+static const struct of_device_id gpio_regulator_dt_ids[] = {
+ { .compatible = "gpio-regulator", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, gpio_regulator_dt_ids);
+
+static int gpio_regulator_probe_dt(struct platform_device *pdev)
+{
+ struct device_node *states, *np = pdev->dev.of_node;
+ struct gpio_regulator_config *config;
+ int ret, i;
+
+ if (!np)
+ return 0;
+
+ config = kzalloc(sizeof(config), GFP_KERNEL);
+ if (!config) {
+ ret = -ENOMEM;
+ goto exit;
+ }
+
+ config->nr_gpios = of_gpio_named_count(np, "gpios");
+ config->gpios = kcalloc(config->nr_gpios, sizeof(struct gpio),
+ GFP_KERNEL);
+ if (!config->gpios) {
+ ret = -ENOMEM;
+ goto exit_free_config;
+ }
+
+ for (i = 0; i < config->nr_gpios; i++) {
+ int gpio = of_get_named_gpio(np, "gpios", i);
+
+ config->gpios[i].gpio = gpio;
+ config->gpios[i].flags = GPIOF_DIR_OUT;
+ }
+
+ config->supply_name =
+ kstrdup(of_get_property(np, "regulator-name", NULL),
+ GFP_KERNEL);
+ of_property_read_u32(np, "startup-delay", &config->startup_delay);
+
+ if (of_get_property(np, "enable-high", NULL))
+ config->enable_high = 1;
+ if (of_get_property(np, "enabled-at-boot", NULL))
+ config->enabled_at_boot = 1;
+ if (of_get_property(np, "regulator-type-current", NULL))
+ config->type = REGULATOR_CURRENT;
+ if (of_get_property(np, "regulator-type-voltage", NULL))
+ config->type = REGULATOR_VOLTAGE;
+
+ states = of_find_node_by_name(np, "states");
+
+ if (states) {
+ struct device_node *child = NULL;
+ while ((child = of_get_next_child(states, child)))
+ config->nr_states++;
+
+ config->states = kcalloc(config->nr_states,
+ sizeof(struct regulator_state),
+ GFP_KERNEL);
+ if (!config->states) {
+ ret = -ENOMEM;
+ goto exit_free_gpios;
+ }
+
+ i = 0;
+ child = NULL;
+ while ((child = of_get_next_child(states, child))) {
+ u32 value, gpios;
+
+ of_property_read_u32(child, "value", &value);
+ of_property_read_u32(child, "gpios", &gpios);
+
+ config->states[i].value = value;
+ config->states[i].gpios = gpios;
+
+ i++;
+ }
+ }
+
+ config->init_data = of_get_regulator_init_data(&pdev->dev, np);
+
+ pdev->dev.platform_data = config;
+
+ return 0;
+
+exit_free_gpios:
+ kfree(config->gpios);
+exit_free_config:
+ kfree(config);
+exit:
+ return ret;
+}
+#else
+static int gpio_regulator_probe_dt(struct platform_device *dev)
+{
+ return 0;
+}
+#endif
+
static int __devinit gpio_regulator_probe(struct platform_device *pdev)
{
- struct gpio_regulator_config *config = pdev->dev.platform_data;
+ struct gpio_regulator_config *config;
struct gpio_regulator_data *drvdata;
struct regulator_config cfg = { };
int ptr, ret, state;
+ ret = gpio_regulator_probe_dt(pdev);
+ if (ret < 0)
+ return ret;
+
+ config = pdev->dev.platform_data;
+ if (!config) {
+ dev_err(&pdev->dev, "Platform data missing\n");
+ return -EINVAL;
+ }
+
drvdata = devm_kzalloc(&pdev->dev, sizeof(struct gpio_regulator_data),
GFP_KERNEL);
if (drvdata == NULL) {
@@ -276,6 +391,7 @@ static struct platform_driver gpio_regulator_driver = {
.driver = {
.name = "gpio-regulator",
.owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(gpio_regulator_dt_ids),
},
};
--
1.7.11.4
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