#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pwm.h>
+#include <linux/gpio/consumer.h>
struct pwm_regulator_data {
/* Shared */
/* Continuous voltage */
int volt_uV;
+
+ /* Enable GPIO */
+ struct gpio_desc *enb_gpio;
};
struct pwm_voltages {
unsigned selector)
{
struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
- unsigned int pwm_reg_period;
+ struct pwm_args pargs;
int dutycycle;
int ret;
- pwm_reg_period = pwm_get_period(drvdata->pwm);
+ pwm_get_args(drvdata->pwm, &pargs);
- dutycycle = (pwm_reg_period *
+ dutycycle = (pargs.period *
drvdata->duty_cycle_table[selector].dutycycle) / 100;
- ret = pwm_config(drvdata->pwm, dutycycle, pwm_reg_period);
+ ret = pwm_config(drvdata->pwm, dutycycle, pargs.period);
if (ret) {
- dev_err(&rdev->dev, "Failed to configure PWM\n");
+ dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
return ret;
}
{
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);
}
pwm_disable(drvdata->pwm);
+ if (drvdata->enb_gpio)
+ gpiod_set_value_cansleep(drvdata->enb_gpio, 0);
+
return 0;
}
{
struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
- return pwm_is_enabled(drvdata->pwm);
-}
+ if (drvdata->enb_gpio && !gpiod_get_value_cansleep(drvdata->enb_gpio))
+ return false;
-/**
- * Continuous voltage call-backs
- */
-static int pwm_voltage_to_duty_cycle_percentage(struct regulator_dev *rdev, int req_uV)
-{
- int min_uV = rdev->constraints->min_uV;
- int max_uV = rdev->constraints->max_uV;
- int diff = max_uV - min_uV;
-
- return ((req_uV * 100) - (min_uV * 100)) / diff;
+ 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 ramp_delay = rdev->constraints->ramp_delay;
- unsigned int period = pwm_get_period(drvdata->pwm);
- int duty_cycle;
+ 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 old_uV = pwm_regulator_get_voltage(rdev);
int ret;
- duty_cycle = pwm_voltage_to_duty_cycle_percentage(rdev, min_uV);
-
- ret = pwm_config(drvdata->pwm, (period / 100) * duty_cycle, period);
- if (ret) {
- dev_err(&rdev->dev, "Failed to configure PWM\n");
- return ret;
+ pwm_get_args(drvdata->pwm, &pargs);
+ diff = rdev->constraints->max_uV - rdev->constraints->min_uV;
+
+ /* 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.
+ */
+ 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);
}
- ret = pwm_enable(drvdata->pwm);
+ ret = pwm_config(drvdata->pwm, duty_pulse, pargs.period);
if (ret) {
- dev_err(&rdev->dev, "Failed to enable PWM\n");
+ dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
return ret;
}
+
drvdata->volt_uV = min_uV;
- /* Delay required by PWM regulator to settle to the new voltage */
- usleep_range(ramp_delay, ramp_delay + 1000);
+ if ((ramp_delay == 0) || !pwm_regulator_is_enabled(rdev))
+ return 0;
+
+ /* Ramp delay is in uV/uS. Adjust to uS and delay */
+ ramp_delay = DIV_ROUND_UP(abs(min_uV - old_uV), ramp_delay);
+ usleep_range(ramp_delay, ramp_delay + DIV_ROUND_UP(ramp_delay, 10));
return 0;
}
if ((length < sizeof(*duty_cycle_table)) ||
(length % sizeof(*duty_cycle_table))) {
- dev_err(&pdev->dev,
- "voltage-table length(%d) is invalid\n",
+ dev_err(&pdev->dev, "voltage-table length(%d) is invalid\n",
length);
return -EINVAL;
}
(u32 *)duty_cycle_table,
length / sizeof(u32));
if (ret) {
- dev_err(&pdev->dev, "Failed to read voltage-table\n");
+ dev_err(&pdev->dev, "Failed to read voltage-table: %d\n", ret);
return ret;
}
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) {
drvdata->pwm = devm_pwm_get(&pdev->dev, NULL);
if (IS_ERR(drvdata->pwm)) {
- dev_err(&pdev->dev, "Failed to get PWM\n");
- return PTR_ERR(drvdata->pwm);
+ ret = PTR_ERR(drvdata->pwm);
+ dev_err(&pdev->dev, "Failed to get PWM: %d\n", ret);
+ return ret;
}
+ 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;
+ }
+
+ /*
+ * FIXME: pwm_apply_args() should be removed when switching to the
+ * atomic PWM API.
+ */
+ pwm_apply_args(drvdata->pwm);
+
regulator = devm_regulator_register(&pdev->dev,
&drvdata->desc, &config);
if (IS_ERR(regulator)) {
- dev_err(&pdev->dev, "Failed to register regulator %s\n",
- drvdata->desc.name);
- return PTR_ERR(regulator);
+ ret = PTR_ERR(regulator);
+ dev_err(&pdev->dev, "Failed to register regulator %s: %d\n",
+ drvdata->desc.name, ret);
+ return ret;
}
return 0;
projects / deliverable / linux.git / blobdiff