diff mbox

[v3,12/12] regulator: pwm: properly initialize the ->state field

Message ID 1442828009-6241-13-git-send-email-boris.brezillon@free-electrons.com
State New
Headers show

Commit Message

Boris BREZILLON Sept. 21, 2015, 9:33 a.m. UTC
The ->state field is currently initialized to 0, thus referencing the
voltage selector at index 0, which might not reflect the current voltage
value.
If possible, retrieve the current voltage selector from the PWM state, else
return -EINVAL.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
---
 drivers/regulator/pwm-regulator.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

Comments

Mark Brown Sept. 21, 2015, 9:10 p.m. UTC | #1
On Mon, Sep 21, 2015 at 11:33:29AM +0200, Boris Brezillon wrote:
> The ->state field is currently initialized to 0, thus referencing the
> voltage selector at index 0, which might not reflect the current voltage
> value.
> If possible, retrieve the current voltage selector from the PWM state, else
> return -EINVAL.

Acked-by: Mark Brown <broonie@kernel.org>
diff mbox

Patch

diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c
index 9ffdbd6..449e3b3 100644
--- a/drivers/regulator/pwm-regulator.c
+++ b/drivers/regulator/pwm-regulator.c
@@ -41,10 +41,35 @@  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);
+
+	if (!pwm_state.period)
+		return;
+
+	dutycycle = (pwm_state.duty_cycle * 100) / pwm_state.period;
+
+	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;
 }
 
@@ -211,6 +236,7 @@  static int pwm_regulator_init_table(struct platform_device *pdev,
 		return ret;
 	}
 
+	drvdata->state			= -EINVAL;
 	drvdata->duty_cycle_table	= duty_cycle_table;
 	pwm_regulator_desc.ops		= &pwm_regulator_voltage_table_ops;
 	pwm_regulator_desc.n_voltages	= length / sizeof(*duty_cycle_table);