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authorThierry Reding <thierry.reding@gmail.com>2016-07-25 16:23:40 +0200
committerThierry Reding <thierry.reding@gmail.com>2016-07-25 16:23:40 +0200
commit53de7c26ded7f5e954bfc202dffc43c0dd165337 (patch)
tree1f6be162967231ef755f6a1b5794d11e62bf63a7
parent070d9a930620399a83127be6e7c6d2c2cc84a553 (diff)
parent58fd822b2e344edae6b4dbc09b19bd0c4a2f8f60 (diff)
downloadlinux-53de7c26ded7f5e954bfc202dffc43c0dd165337.tar.bz2
Merge branch 'for-4.8/regulator' into for-next
-rw-r--r--Documentation/devicetree/bindings/regulator/pwm-regulator.txt26
-rw-r--r--drivers/regulator/pwm-regulator.c196
2 files changed, 173 insertions, 49 deletions
diff --git a/Documentation/devicetree/bindings/regulator/pwm-regulator.txt b/Documentation/devicetree/bindings/regulator/pwm-regulator.txt
index ed936f0f34f2..3aeba9f86ed8 100644
--- a/Documentation/devicetree/bindings/regulator/pwm-regulator.txt
+++ b/Documentation/devicetree/bindings/regulator/pwm-regulator.txt
@@ -34,20 +34,44 @@ Only required for Voltage Table Mode:
First cell is voltage in microvolts (uV)
Second cell is duty-cycle in percent (%)
+Optional properties for Continuous mode:
+- pwm-dutycycle-unit: Integer value encoding the duty cycle unit. If not
+ defined, <100> is assumed, meaning that
+ pwm-dutycycle-range contains values expressed in
+ percent.
+
+- pwm-dutycycle-range: Should contain 2 entries. The first entry is encoding
+ the dutycycle for regulator-min-microvolt and the
+ second one the dutycycle for regulator-max-microvolt.
+ Duty cycle values are expressed in pwm-dutycycle-unit.
+ If not defined, <0 100> is assumed.
+
NB: To be clear, if voltage-table is provided, then the device will be used
in Voltage Table Mode. If no voltage-table is provided, then the device will
be used in Continuous Voltage Mode.
+Optional properties:
+--------------------
+- enable-gpios: GPIO to use to enable/disable the regulator
+
Any property defined as part of the core regulator binding can also be used.
(See: ../regulator/regulator.txt)
-Continuous Voltage Example:
+Continuous Voltage With Enable GPIO Example:
pwm_regulator {
compatible = "pwm-regulator;
pwms = <&pwm1 0 8448 0>;
+ enable-gpios = <&gpio0 23 GPIO_ACTIVE_HIGH>;
regulator-min-microvolt = <1016000>;
regulator-max-microvolt = <1114000>;
regulator-name = "vdd_logic";
+ /* unit == per-mille */
+ pwm-dutycycle-unit = <1000>;
+ /*
+ * Inverted PWM logic, and the duty cycle range is limited
+ * to 30%-70%.
+ */
+ pwm-dutycycle-range <700 300>; /* */
};
Voltage Table Example:
diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c
index fafa3488e960..c24524242da2 100644
--- a/drivers/regulator/pwm-regulator.c
+++ b/drivers/regulator/pwm-regulator.c
@@ -20,6 +20,13 @@
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pwm.h>
+#include <linux/gpio/consumer.h>
+
+struct pwm_continuous_reg_data {
+ unsigned int min_uV_dutycycle;
+ unsigned int max_uV_dutycycle;
+ unsigned int dutycycle_unit;
+};
struct pwm_regulator_data {
/* Shared */
@@ -28,6 +35,9 @@ struct pwm_regulator_data {
/* Voltage table */
struct pwm_voltages *duty_cycle_table;
+ /* Continuous mode info */
+ struct pwm_continuous_reg_data continuous;
+
/* regulator descriptor */
struct regulator_desc desc;
@@ -36,8 +46,8 @@ struct pwm_regulator_data {
int state;
- /* Continuous voltage */
- int volt_uV;
+ /* Enable GPIO */
+ struct gpio_desc *enb_gpio;
};
struct pwm_voltages {
@@ -48,10 +58,31 @@ struct pwm_voltages {
/**
* Voltage table call-backs
*/
+static void pwm_regulator_init_state(struct regulator_dev *rdev)
+{
+ struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
+ struct pwm_state pwm_state;
+ unsigned int dutycycle;
+ int i;
+
+ pwm_get_state(drvdata->pwm, &pwm_state);
+ dutycycle = pwm_get_relative_duty_cycle(&pwm_state, 100);
+
+ for (i = 0; i < rdev->desc->n_voltages; i++) {
+ if (dutycycle == drvdata->duty_cycle_table[i].dutycycle) {
+ drvdata->state = i;
+ return;
+ }
+ }
+}
+
static int pwm_regulator_get_voltage_sel(struct regulator_dev *rdev)
{
struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
+ if (drvdata->state < 0)
+ pwm_regulator_init_state(rdev);
+
return drvdata->state;
}
@@ -59,16 +90,14 @@ static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev,
unsigned selector)
{
struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
- struct pwm_args pargs;
- int dutycycle;
+ struct pwm_state pstate;
int ret;
- pwm_get_args(drvdata->pwm, &pargs);
-
- dutycycle = (pargs.period *
- drvdata->duty_cycle_table[selector].dutycycle) / 100;
+ pwm_init_state(drvdata->pwm, &pstate);
+ pwm_set_relative_duty_cycle(&pstate,
+ drvdata->duty_cycle_table[selector].dutycycle, 100);
- ret = pwm_config(drvdata->pwm, dutycycle, pargs.period);
+ ret = pwm_apply_state(drvdata->pwm, &pstate);
if (ret) {
dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
return ret;
@@ -94,6 +123,9 @@ static int pwm_regulator_enable(struct regulator_dev *dev)
{
struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
+ if (drvdata->enb_gpio)
+ gpiod_set_value_cansleep(drvdata->enb_gpio, 1);
+
return pwm_enable(drvdata->pwm);
}
@@ -103,6 +135,9 @@ static int pwm_regulator_disable(struct regulator_dev *dev)
pwm_disable(drvdata->pwm);
+ if (drvdata->enb_gpio)
+ gpiod_set_value_cansleep(drvdata->enb_gpio, 0);
+
return 0;
}
@@ -110,64 +145,100 @@ static int pwm_regulator_is_enabled(struct regulator_dev *dev)
{
struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
+ if (drvdata->enb_gpio && !gpiod_get_value_cansleep(drvdata->enb_gpio))
+ return false;
+
return pwm_is_enabled(drvdata->pwm);
}
static int pwm_regulator_get_voltage(struct regulator_dev *rdev)
{
struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
+ unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
+ unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
+ unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
+ int min_uV = rdev->constraints->min_uV;
+ int max_uV = rdev->constraints->max_uV;
+ int diff_uV = max_uV - min_uV;
+ struct pwm_state pstate;
+ unsigned int diff_duty;
+ unsigned int voltage;
+
+ pwm_get_state(drvdata->pwm, &pstate);
+
+ voltage = pwm_get_relative_duty_cycle(&pstate, duty_unit);
+
+ /*
+ * The dutycycle for min_uV might be greater than the one for max_uV.
+ * This is happening when the user needs an inversed polarity, but the
+ * PWM device does not support inversing it in hardware.
+ */
+ if (max_uV_duty < min_uV_duty) {
+ voltage = min_uV_duty - voltage;
+ diff_duty = min_uV_duty - max_uV_duty;
+ } else {
+ voltage = voltage - min_uV_duty;
+ diff_duty = max_uV_duty - min_uV_duty;
+ }
+
+ voltage = DIV_ROUND_CLOSEST_ULL((u64)voltage * diff_uV, diff_duty);
- return drvdata->volt_uV;
+ return voltage + min_uV;
}
static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
- int min_uV, int max_uV,
- unsigned *selector)
+ int req_min_uV, int req_max_uV,
+ unsigned int *selector)
{
struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
+ unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
+ unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
+ unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
unsigned int ramp_delay = rdev->constraints->ramp_delay;
- struct pwm_args pargs;
- unsigned int req_diff = min_uV - rdev->constraints->min_uV;
- unsigned int diff;
- unsigned int duty_pulse;
- u64 req_period;
- u32 rem;
+ int min_uV = rdev->constraints->min_uV;
+ int max_uV = rdev->constraints->max_uV;
+ int diff_uV = max_uV - min_uV;
+ struct pwm_state pstate;
+ int old_uV = pwm_regulator_get_voltage(rdev);
+ unsigned int diff_duty;
+ unsigned int dutycycle;
int ret;
- pwm_get_args(drvdata->pwm, &pargs);
- diff = rdev->constraints->max_uV - rdev->constraints->min_uV;
+ pwm_init_state(drvdata->pwm, &pstate);
- /* First try to find out if we get the iduty cycle time which is
- * factor of PWM period time. If (request_diff_to_min * pwm_period)
- * is perfect divided by voltage_range_diff then it is possible to
- * get duty cycle time which is factor of PWM period. This will help
- * to get output voltage nearer to requested value as there is no
- * calculation loss.
+ /*
+ * The dutycycle for min_uV might be greater than the one for max_uV.
+ * This is happening when the user needs an inversed polarity, but the
+ * PWM device does not support inversing it in hardware.
*/
- req_period = req_diff * pargs.period;
- div_u64_rem(req_period, diff, &rem);
- if (!rem) {
- do_div(req_period, diff);
- duty_pulse = (unsigned int)req_period;
- } else {
- duty_pulse = (pargs.period / 100) * ((req_diff * 100) / diff);
- }
+ if (max_uV_duty < min_uV_duty)
+ diff_duty = min_uV_duty - max_uV_duty;
+ else
+ diff_duty = max_uV_duty - min_uV_duty;
+
+ dutycycle = DIV_ROUND_CLOSEST_ULL((u64)(req_min_uV - min_uV) *
+ diff_duty,
+ diff_uV);
+
+ if (max_uV_duty < min_uV_duty)
+ dutycycle = min_uV_duty - dutycycle;
+ else
+ dutycycle = min_uV_duty + dutycycle;
+
+ pwm_set_relative_duty_cycle(&pstate, dutycycle, duty_unit);
- ret = pwm_config(drvdata->pwm, duty_pulse, pargs.period);
+ ret = pwm_apply_state(drvdata->pwm, &pstate);
if (ret) {
dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
return ret;
}
- ret = pwm_enable(drvdata->pwm);
- if (ret) {
- dev_err(&rdev->dev, "Failed to enable PWM: %d\n", ret);
- return ret;
- }
- drvdata->volt_uV = min_uV;
+ if ((ramp_delay == 0) || !pwm_regulator_is_enabled(rdev))
+ return 0;
- /* Delay required by PWM regulator to settle to the new voltage */
- usleep_range(ramp_delay, ramp_delay + 1000);
+ /* Ramp delay is in uV/uS. Adjust to uS and delay */
+ ramp_delay = DIV_ROUND_UP(abs(req_min_uV - old_uV), ramp_delay);
+ usleep_range(ramp_delay, ramp_delay + DIV_ROUND_UP(ramp_delay, 10));
return 0;
}
@@ -226,6 +297,7 @@ static int pwm_regulator_init_table(struct platform_device *pdev,
return ret;
}
+ drvdata->state = -EINVAL;
drvdata->duty_cycle_table = duty_cycle_table;
memcpy(&drvdata->ops, &pwm_regulator_voltage_table_ops,
sizeof(drvdata->ops));
@@ -238,11 +310,28 @@ static int pwm_regulator_init_table(struct platform_device *pdev,
static int pwm_regulator_init_continuous(struct platform_device *pdev,
struct pwm_regulator_data *drvdata)
{
+ u32 dutycycle_range[2] = { 0, 100 };
+ u32 dutycycle_unit = 100;
+
memcpy(&drvdata->ops, &pwm_regulator_voltage_continuous_ops,
sizeof(drvdata->ops));
drvdata->desc.ops = &drvdata->ops;
drvdata->desc.continuous_voltage_range = true;
+ of_property_read_u32_array(pdev->dev.of_node,
+ "pwm-dutycycle-range",
+ dutycycle_range, 2);
+ of_property_read_u32(pdev->dev.of_node, "pwm-dutycycle-unit",
+ &dutycycle_unit);
+
+ if (dutycycle_range[0] > dutycycle_unit ||
+ dutycycle_range[1] > dutycycle_unit)
+ return -EINVAL;
+
+ drvdata->continuous.dutycycle_unit = dutycycle_unit;
+ drvdata->continuous.min_uV_dutycycle = dutycycle_range[0];
+ drvdata->continuous.max_uV_dutycycle = dutycycle_range[1];
+
return 0;
}
@@ -253,6 +342,7 @@ static int pwm_regulator_probe(struct platform_device *pdev)
struct regulator_dev *regulator;
struct regulator_config config = { };
struct device_node *np = pdev->dev.of_node;
+ enum gpiod_flags gpio_flags;
int ret;
if (!np) {
@@ -290,11 +380,21 @@ static int pwm_regulator_probe(struct platform_device *pdev)
return ret;
}
- /*
- * FIXME: pwm_apply_args() should be removed when switching to the
- * atomic PWM API.
- */
- pwm_apply_args(drvdata->pwm);
+ if (init_data->constraints.boot_on || init_data->constraints.always_on)
+ gpio_flags = GPIOD_OUT_HIGH;
+ else
+ gpio_flags = GPIOD_OUT_LOW;
+ drvdata->enb_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
+ gpio_flags);
+ if (IS_ERR(drvdata->enb_gpio)) {
+ ret = PTR_ERR(drvdata->enb_gpio);
+ dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n", ret);
+ return ret;
+ }
+
+ ret = pwm_adjust_config(drvdata->pwm);
+ if (ret)
+ return ret;
regulator = devm_regulator_register(&pdev->dev,
&drvdata->desc, &config);