[PATCH 1/3] regulator: fixed: add possibility to enable by clock

From: Philippe Schenker
Date: Tue Sep 03 2019 - 04:03:53 EST


This commit adds the possibility to choose the compatible
"regulator-fixed-clock" in devicetree.

This is a special regulator-fixed that has to have a clock, from which
the regulator gets switched on and off.

Signed-off-by: Philippe Schenker <philippe.schenker@xxxxxxxxxxx>
---

drivers/regulator/fixed.c | 86 +++++++++++++++++++++++++++++++++++++--
1 file changed, 83 insertions(+), 3 deletions(-)

diff --git a/drivers/regulator/fixed.c b/drivers/regulator/fixed.c
index 999547dde99d..eadeca9a1a6c 100644
--- a/drivers/regulator/fixed.c
+++ b/drivers/regulator/fixed.c
@@ -23,14 +23,66 @@
#include <linux/gpio/consumer.h>
#include <linux/slab.h>
#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/regulator/of_regulator.h>
#include <linux/regulator/machine.h>
+#include <linux/clk.h>
+

struct fixed_voltage_data {
struct regulator_desc desc;
struct regulator_dev *dev;
+
+ struct clk *enable_clock;
+ unsigned int clk_enable_counter;
+};
+
+struct fixed_dev_type {
+ bool has_enable_clock;
+};
+
+static const struct fixed_dev_type fixed_voltage_data = {
+ .has_enable_clock = false,
};

+static const struct fixed_dev_type fixed_clkenable_data = {
+ .has_enable_clock = true,
+};
+
+static int reg_clock_enable(struct regulator_dev *rdev)
+{
+ struct fixed_voltage_data *priv = rdev_get_drvdata(rdev);
+ int ret = 0;
+
+ ret = clk_prepare_enable(priv->enable_clock);
+ if (ret)
+ return ret;
+
+ priv->clk_enable_counter++;
+
+ return ret;
+}
+
+static int reg_clock_disable(struct regulator_dev *rdev)
+{
+ struct fixed_voltage_data *priv = rdev_get_drvdata(rdev);
+
+ clk_disable_unprepare(priv->enable_clock);
+ priv->clk_enable_counter--;
+
+ return 0;
+}
+
+static int reg_clock_is_enabled(struct regulator_dev *rdev)
+{
+ struct fixed_voltage_data *priv = rdev_get_drvdata(rdev);
+
+ if (priv->clk_enable_counter > 0)
+ return 1;
+
+ return 0;
+}
+

/**
* of_get_fixed_voltage_config - extract fixed_voltage_config structure info
@@ -84,10 +136,19 @@ of_get_fixed_voltage_config(struct device *dev,
static struct regulator_ops fixed_voltage_ops = {
};

+static struct regulator_ops fixed_voltage_clkenabled_ops = {
+ .enable = reg_clock_enable,
+ .disable = reg_clock_disable,
+ .is_enabled = reg_clock_is_enabled,
+};
+
static int reg_fixed_voltage_probe(struct platform_device *pdev)
{
+ struct device *dev = &pdev->dev;
struct fixed_voltage_config *config;
struct fixed_voltage_data *drvdata;
+ const struct fixed_dev_type *drvtype =
+ of_match_device(dev->driver->of_match_table, dev)->data;
struct regulator_config cfg = { };
enum gpiod_flags gflags;
int ret;
@@ -118,7 +179,18 @@ static int reg_fixed_voltage_probe(struct platform_device *pdev)
}
drvdata->desc.type = REGULATOR_VOLTAGE;
drvdata->desc.owner = THIS_MODULE;
- drvdata->desc.ops = &fixed_voltage_ops;
+
+ if (drvtype->has_enable_clock) {
+ drvdata->desc.ops = &fixed_voltage_clkenabled_ops;
+
+ drvdata->enable_clock = devm_clk_get(dev, NULL);
+ if (IS_ERR(drvdata->enable_clock)) {
+ dev_err(dev, "Cant get enable-clock from devicetree\n");
+ return -ENOENT;
+ }
+ } else {
+ drvdata->desc.ops = &fixed_voltage_ops;
+ }

drvdata->desc.enable_time = config->startup_delay;

@@ -191,8 +263,16 @@ static int reg_fixed_voltage_probe(struct platform_device *pdev)

#if defined(CONFIG_OF)
static const struct of_device_id fixed_of_match[] = {
- { .compatible = "regulator-fixed", },
- {},
+ {
+ .compatible = "regulator-fixed",
+ .data = &fixed_voltage_data,
+ },
+ {
+ .compatible = "regulator-fixed-clock",
+ .data = &fixed_clkenable_data,
+ },
+ {
+ },
};
MODULE_DEVICE_TABLE(of, fixed_of_match);
#endif
--
2.23.0