regulator: pwm-regulator: get voltage and duty table from dts

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@rock-chips.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

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
@@ -483,12 +490,6 @@ 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

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
@@ -65,7 +66,6 @@ obj-$(CONFIG_REGULATOR_RC5T583)  += rc5t583-regulator.o
 obj-$(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

drivers/regulator/st-pwm.c → drivers/regulator/pwm-regulator.c

 /*
- * 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,
+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);
+
+	dutycycle = (pwm_reg_period *
+		    drvdata->duty_cycle_table[selector].dutycycle) / 100;
 
-	ret = pwm_config(drvdata->pwm, dutycycle, ST_PWM_REG_PERIOD);
+	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,
+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@linaro.org>");
-MODULE_DESCRIPTION("ST PWM Regulator Driver");
-MODULE_ALIAS("platform:st_pwm-regulator");
+MODULE_DESCRIPTION("PWM Regulator Driver");
+MODULE_ALIAS("platform:pwm-regulator");