@@ -238,6 +238,43 @@ static void sti_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
mutex_unlock(&pc->sti_pwm_lock);
}
+static void sti_pwm_get_state(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct sti_pwm_chip *pc = to_sti_pwmchip(chip);
+ unsigned int regval, prescaler;
+ int ret;
+
+ /* The clock has to be enabled to access PWM registers */
+ ret = clk_enable(pc->clk);
+ if (ret) {
+ dev_err(chip->dev, "Failed to enable PWM clk");
+ return;
+ }
+
+ regmap_field_read(pc->prescale_high, ®val);
+ prescaler = regval << 4;
+ regmap_field_read(pc->prescale_low, ®val);
+ prescaler |= regval;
+ state->period = DIV_ROUND_CLOSEST_ULL((u64)(prescaler + 1) *
+ NSEC_PER_SEC *
+ (pc->cdata->max_pwm_cnt + 1),
+ pc->clk_rate);
+
+ regmap_read(pc->regmap, STI_DS_REG(pwm->hwpwm), ®val);
+ state->duty_cycle = DIV_ROUND_CLOSEST_ULL((u64)(regval + 1) *
+ state->period,
+ pc->cdata->max_pwm_cnt + 1);
+
+ regmap_field_read(pc->pwm_en, ®val);
+ state->enabled = regval;
+
+ state->polarity = PWM_POLARITY_NORMAL;
+
+ clk_disable(pc->clk);
+}
+
static void sti_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct sti_pwm_chip *pc = to_sti_pwmchip(chip);
@@ -249,6 +286,7 @@ static const struct pwm_ops sti_pwm_ops = {
.config = sti_pwm_config,
.enable = sti_pwm_enable,
.disable = sti_pwm_disable,
+ .get_state = sti_pwm_get_state,
.free = sti_pwm_free,
.owner = THIS_MODULE,
};
Implement ->get_state() to provide support for initial state retrieval. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> --- drivers/pwm/pwm-sti.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+)