[PATCH v7 1/2] regulator: pwm-regulator: get voltage and duty table from dts

From: Chris Zhong
Date: Sat Sep 27 2014 - 22:29:23 EST


rename st-pwm to pwm-regulator. And support getting voltage & duty table from
device tree, other platforms can also use this driver without any modify.

Signed-off-by: Chris Zhong <zyw@xxxxxxxxxxxxxx>
Reviewed-by: Doug Anderson <dianders@xxxxxxxxxxxx>
Tested-by: Doug Anderson <dianders@xxxxxxxxxxxx>

---

Changes in v7:
Adviced by Mark Brown
- re-edit changelog

Changes in v6: None
Changes in v4:
Adviced by Doug Anderson
- improve kconfig
- add const for desc structure

Changes in v3:
Adviced by Doug Anderson
- Make Kconfig & Makefile alphabetical
- remove pwm_reg_period from pwm_regulator_data
- modify the calculation in pwm_regulator_set_voltage_sel
- add length validity check

Changes in v2:
Adviced by Lee Jones
- rename the file
- remove all the prefix st_
- add depend on PWM in Kconfig

drivers/regulator/Kconfig | 13 +-
drivers/regulator/Makefile | 2 +-
drivers/regulator/{st-pwm.c => pwm-regulator.c} | 147 ++++++++++++-----------
3 files changed, 85 insertions(+), 77 deletions(-)
rename drivers/regulator/{st-pwm.c => pwm-regulator.c} (44%)

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index fb32bab..b927cab 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -449,6 +449,13 @@ config REGULATOR_PFUZE100
Say y here to support the regulators found on the Freescale
PFUZE100/PFUZE200 PMIC.

+config REGULATOR_PWM
+ tristate "PWM voltage regulator"
+ depends on PWM
+ help
+ This driver supports PWM controlled voltage regulators. PWM
+ duty cycle can increase or decrease the voltage.
+
config REGULATOR_RC5T583
tristate "RICOH RC5T583 Power regulators"
depends on MFD_RC5T583
@@ -493,12 +500,6 @@ config REGULATOR_S5M8767
via I2C bus. S5M8767A have 9 Bucks and 28 LDOs output and
supports DVS mode with 8bits of output voltage control.

-config REGULATOR_ST_PWM
- tristate "STMicroelectronics PWM voltage regulator"
- depends on ARCH_STI
- help
- This driver supports ST's PWM controlled voltage regulators.
-
config REGULATOR_TI_ABB
tristate "TI Adaptive Body Bias on-chip LDO"
depends on ARCH_OMAP
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 236fdbb..f3cf5a5 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -57,6 +57,7 @@ obj-$(CONFIG_REGULATOR_MC13892) += mc13892-regulator.o
obj-$(CONFIG_REGULATOR_MC13XXX_CORE) += mc13xxx-regulator-core.o
obj-$(CONFIG_REGULATOR_PALMAS) += palmas-regulator.o
obj-$(CONFIG_REGULATOR_PFUZE100) += pfuze100-regulator.o
+obj-$(CONFIG_REGULATOR_PWM) += pwm-regulator.o
obj-$(CONFIG_REGULATOR_TPS51632) += tps51632-regulator.o
obj-$(CONFIG_REGULATOR_PBIAS) += pbias-regulator.o
obj-$(CONFIG_REGULATOR_PCAP) += pcap-regulator.o
@@ -66,7 +67,6 @@ obj-$(CONFIG_REGULATOR_RK808) += rk808-regulator.o
obj-$(CONFIG_REGULATOR_S2MPA01) += s2mpa01.o
obj-$(CONFIG_REGULATOR_S2MPS11) += s2mps11.o
obj-$(CONFIG_REGULATOR_S5M8767) += s5m8767.o
-obj-$(CONFIG_REGULATOR_ST_PWM) += st-pwm.o
obj-$(CONFIG_REGULATOR_STW481X_VMMC) += stw481x-vmmc.o
obj-$(CONFIG_REGULATOR_TI_ABB) += ti-abb-regulator.o
obj-$(CONFIG_REGULATOR_TPS6105X) += tps6105x-regulator.o
diff --git a/drivers/regulator/st-pwm.c b/drivers/regulator/pwm-regulator.c
similarity index 44%
rename from drivers/regulator/st-pwm.c
rename to drivers/regulator/pwm-regulator.c
index 5ea78df..d3f55ea 100644
--- a/drivers/regulator/st-pwm.c
+++ b/drivers/regulator/pwm-regulator.c
@@ -1,5 +1,5 @@
/*
- * Regulator driver for ST's PWM Regulators
+ * Regulator driver for PWM Regulators
*
* Copyright (C) 2014 - STMicroelectronics Inc.
*
@@ -20,43 +20,40 @@
#include <linux/of_device.h>
#include <linux/pwm.h>

-#define ST_PWM_REG_PERIOD 8448
-
-struct st_pwm_regulator_pdata {
- const struct regulator_desc *desc;
- struct st_pwm_voltages *duty_cycle_table;
-};
-
-struct st_pwm_regulator_data {
- const struct st_pwm_regulator_pdata *pdata;
+struct pwm_regulator_data {
+ struct regulator_desc desc;
+ struct pwm_voltages *duty_cycle_table;
struct pwm_device *pwm;
bool enabled;
int state;
};

-struct st_pwm_voltages {
+struct pwm_voltages {
unsigned int uV;
unsigned int dutycycle;
};

-static int st_pwm_regulator_get_voltage_sel(struct regulator_dev *dev)
+static int pwm_regulator_get_voltage_sel(struct regulator_dev *dev)
{
- struct st_pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
+ struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);

return drvdata->state;
}

-static int st_pwm_regulator_set_voltage_sel(struct regulator_dev *dev,
- unsigned selector)
+static int pwm_regulator_set_voltage_sel(struct regulator_dev *dev,
+ unsigned selector)
{
- struct st_pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
+ struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
+ unsigned int pwm_reg_period;
int dutycycle;
int ret;

- dutycycle = (ST_PWM_REG_PERIOD / 100) *
- drvdata->pdata->duty_cycle_table[selector].dutycycle;
+ pwm_reg_period = pwm_get_period(drvdata->pwm);

- ret = pwm_config(drvdata->pwm, dutycycle, ST_PWM_REG_PERIOD);
+ dutycycle = (pwm_reg_period *
+ drvdata->duty_cycle_table[selector].dutycycle) / 100;
+
+ ret = pwm_config(drvdata->pwm, dutycycle, pwm_reg_period);
if (ret) {
dev_err(&dev->dev, "Failed to configure PWM\n");
return ret;
@@ -76,61 +73,40 @@ static int st_pwm_regulator_set_voltage_sel(struct regulator_dev *dev,
return 0;
}

-static int st_pwm_regulator_list_voltage(struct regulator_dev *dev,
- unsigned selector)
+static int pwm_regulator_list_voltage(struct regulator_dev *dev,
+ unsigned selector)
{
- struct st_pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
+ struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);

- if (selector >= dev->desc->n_voltages)
+ if (selector >= drvdata->desc.n_voltages)
return -EINVAL;

- return drvdata->pdata->duty_cycle_table[selector].uV;
+ return drvdata->duty_cycle_table[selector].uV;
}

-static struct regulator_ops st_pwm_regulator_voltage_ops = {
- .set_voltage_sel = st_pwm_regulator_set_voltage_sel,
- .get_voltage_sel = st_pwm_regulator_get_voltage_sel,
- .list_voltage = st_pwm_regulator_list_voltage,
+static struct regulator_ops pwm_regulator_voltage_ops = {
+ .set_voltage_sel = pwm_regulator_set_voltage_sel,
+ .get_voltage_sel = pwm_regulator_get_voltage_sel,
+ .list_voltage = pwm_regulator_list_voltage,
.map_voltage = regulator_map_voltage_iterate,
};

-static struct st_pwm_voltages b2105_duty_cycle_table[] = {
- { .uV = 1114000, .dutycycle = 0, },
- { .uV = 1095000, .dutycycle = 10, },
- { .uV = 1076000, .dutycycle = 20, },
- { .uV = 1056000, .dutycycle = 30, },
- { .uV = 1036000, .dutycycle = 40, },
- { .uV = 1016000, .dutycycle = 50, },
- /* WARNING: Values above 50% duty-cycle cause boot failures. */
-};
-
-static const struct regulator_desc b2105_desc = {
- .name = "b2105-pwm-regulator",
- .ops = &st_pwm_regulator_voltage_ops,
+static const struct regulator_desc pwm_regulator_desc = {
+ .name = "pwm-regulator",
+ .ops = &pwm_regulator_voltage_ops,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
- .n_voltages = ARRAY_SIZE(b2105_duty_cycle_table),
.supply_name = "pwm",
};

-static const struct st_pwm_regulator_pdata b2105_info = {
- .desc = &b2105_desc,
- .duty_cycle_table = b2105_duty_cycle_table,
-};
-
-static const struct of_device_id st_pwm_of_match[] = {
- { .compatible = "st,b2105-pwm-regulator", .data = &b2105_info, },
- { },
-};
-MODULE_DEVICE_TABLE(of, st_pwm_of_match);
-
-static int st_pwm_regulator_probe(struct platform_device *pdev)
+static int pwm_regulator_probe(struct platform_device *pdev)
{
- struct st_pwm_regulator_data *drvdata;
+ struct pwm_regulator_data *drvdata;
+ struct property *prop;
struct regulator_dev *regulator;
struct regulator_config config = { };
struct device_node *np = pdev->dev.of_node;
- const struct of_device_id *of_match;
+ int length, ret;

if (!np) {
dev_err(&pdev->dev, "Device Tree node missing\n");
@@ -141,12 +117,37 @@ static int st_pwm_regulator_probe(struct platform_device *pdev)
if (!drvdata)
return -ENOMEM;

- of_match = of_match_device(st_pwm_of_match, &pdev->dev);
- if (!of_match) {
- dev_err(&pdev->dev, "failed to match of device\n");
- return -ENODEV;
+ memcpy(&drvdata->desc, &pwm_regulator_desc, sizeof(pwm_regulator_desc));
+
+ /* determine the number of voltage-table */
+ prop = of_find_property(np, "voltage-table", &length);
+ if (!prop) {
+ dev_err(&pdev->dev, "No voltage-table\n");
+ return -EINVAL;
+ }
+
+ if ((length < sizeof(*drvdata->duty_cycle_table)) ||
+ (length % sizeof(*drvdata->duty_cycle_table))) {
+ dev_err(&pdev->dev, "voltage-table length(%d) is invalid\n",
+ length);
+ return -EINVAL;
+ }
+
+ drvdata->desc.n_voltages = length / sizeof(*drvdata->duty_cycle_table);
+
+ drvdata->duty_cycle_table = devm_kzalloc(&pdev->dev,
+ length, GFP_KERNEL);
+ if (!drvdata->duty_cycle_table)
+ return -ENOMEM;
+
+ /* read voltage table from DT property */
+ ret = of_property_read_u32_array(np, "voltage-table",
+ (u32 *)drvdata->duty_cycle_table,
+ length / sizeof(u32));
+ if (ret < 0) {
+ dev_err(&pdev->dev, "read voltage-table failed\n");
+ return ret;
}
- drvdata->pdata = of_match->data;

config.init_data = of_get_regulator_init_data(&pdev->dev, np);
if (!config.init_data)
@@ -163,28 +164,34 @@ static int st_pwm_regulator_probe(struct platform_device *pdev)
}

regulator = devm_regulator_register(&pdev->dev,
- drvdata->pdata->desc, &config);
+ &drvdata->desc, &config);
if (IS_ERR(regulator)) {
dev_err(&pdev->dev, "Failed to register regulator %s\n",
- drvdata->pdata->desc->name);
+ drvdata->desc.name);
return PTR_ERR(regulator);
}

return 0;
}

-static struct platform_driver st_pwm_regulator_driver = {
+static const struct of_device_id pwm_of_match[] = {
+ { .compatible = "pwm-regulator" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, pwm_of_match);
+
+static struct platform_driver pwm_regulator_driver = {
.driver = {
- .name = "st-pwm-regulator",
+ .name = "pwm-regulator",
.owner = THIS_MODULE,
- .of_match_table = of_match_ptr(st_pwm_of_match),
+ .of_match_table = of_match_ptr(pwm_of_match),
},
- .probe = st_pwm_regulator_probe,
+ .probe = pwm_regulator_probe,
};

-module_platform_driver(st_pwm_regulator_driver);
+module_platform_driver(pwm_regulator_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Lee Jones <lee.jones@xxxxxxxxxx>");
-MODULE_DESCRIPTION("ST PWM Regulator Driver");
-MODULE_ALIAS("platform:st_pwm-regulator");
+MODULE_DESCRIPTION("PWM Regulator Driver");
+MODULE_ALIAS("platform:pwm-regulator");
--
1.7.9.5

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