[PATCH 11/16] pwm: crc: Implement apply() method to support the new atomic PWM API

Hans de Goede hdegoede at redhat.com
Sat Jun 6 20:25:56 UTC 2020


Replace the enable, disable and config pwm_ops with an apply op,
to support the new atomic PWM API.

Signed-off-by: Hans de Goede <hdegoede at redhat.com>
---
 drivers/pwm/pwm-crc.c | 107 +++++++++++++++++++++++-------------------
 1 file changed, 59 insertions(+), 48 deletions(-)

diff --git a/drivers/pwm/pwm-crc.c b/drivers/pwm/pwm-crc.c
index 53734bcf67e1..58c7e9ef7278 100644
--- a/drivers/pwm/pwm-crc.c
+++ b/drivers/pwm/pwm-crc.c
@@ -41,70 +41,81 @@ static inline struct crystalcove_pwm *to_crc_pwm(struct pwm_chip *pc)
 	return container_of(pc, struct crystalcove_pwm, chip);
 }
 
-static int crc_pwm_calc_clk_div(int period_ns)
+static int crc_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+			 const struct pwm_state *state)
 {
-	int clk_div;
-
-	clk_div = PWM_BASE_CLK_MHZ * period_ns / (256 * NSEC_PER_MHZ);
-	/* clk_div 1 - 128, maps to register values 0-127 */
-	if (clk_div > 0)
-		clk_div--;
-
-	return clk_div;
-}
-
-static int crc_pwm_enable(struct pwm_chip *c, struct pwm_device *pwm)
-{
-	struct crystalcove_pwm *crc_pwm = to_crc_pwm(c);
-	int div = crc_pwm_calc_clk_div(pwm_get_period(pwm));
-
-	regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, div | PWM_OUTPUT_ENABLE);
-	regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 1);
-
-	return 0;
-}
-
-static void crc_pwm_disable(struct pwm_chip *c, struct pwm_device *pwm)
-{
-	struct crystalcove_pwm *crc_pwm = to_crc_pwm(c);
-	int div = crc_pwm_calc_clk_div(pwm_get_period(pwm));
-
-	regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 0);
-	regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, div);
-}
-
-static int crc_pwm_config(struct pwm_chip *c, struct pwm_device *pwm,
-			  int duty_ns, int period_ns)
-{
-	struct crystalcove_pwm *crc_pwm = to_crc_pwm(c);
+	struct crystalcove_pwm *crc_pwm = to_crc_pwm(chip);
+	int err, clk_div, level, pwm_output_enable;
 	struct device *dev = crc_pwm->chip.dev;
-	int level;
 
-	if (period_ns > PWM_MAX_PERIOD_NS) {
+	if (state->period > PWM_MAX_PERIOD_NS) {
 		dev_err(dev, "un-supported period_ns\n");
 		return -EINVAL;
 	}
 
-	if (pwm_get_period(pwm) != period_ns) {
-		int clk_div = crc_pwm_calc_clk_div(period_ns);
+	if (state->polarity != PWM_POLARITY_NORMAL)
+		return -ENOTSUPP;
+
+	if (pwm_is_enabled(pwm) && !state->enabled) {
+		err = regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 0);
+		if (err) {
+			dev_err(dev, "Error writing BACKLIGHT_EN %d\n", err);
+			return err;
+		}
+	}
+
+	if (pwm_get_duty_cycle(pwm) != state->duty_cycle ||
+	    pwm_get_period(pwm) != state->period) {
+		level = state->duty_cycle * PWM_MAX_LEVEL / state->period;
 
+		err = regmap_write(crc_pwm->regmap, PWM0_DUTY_CYCLE, level);
+		if (err) {
+			dev_err(dev, "Error writing PWM0_DUTY_CYCLE %d\n", err);
+			return err;
+		}
+	}
+
+	if (pwm_is_enabled(pwm) && state->enabled &&
+	    pwm_get_period(pwm) != state->period) {
 		/* changing the clk divisor, clear PWM_OUTPUT_ENABLE first */
-		regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, 0);
-		regmap_write(crc_pwm->regmap, PWM0_CLK_DIV,
-					clk_div | PWM_OUTPUT_ENABLE);
+		err = regmap_write(crc_pwm->regmap, PWM0_CLK_DIV, 0);
+		if (err) {
+			dev_err(dev, "Error writing PWM0_CLK_DIV %d\n", err);
+			return err;
+		}
 	}
 
-	/* change the pwm duty cycle */
-	level = duty_ns * PWM_MAX_LEVEL / period_ns;
-	regmap_write(crc_pwm->regmap, PWM0_DUTY_CYCLE, level);
+	if (pwm_get_period(pwm) != state->period ||
+	    pwm_is_enabled(pwm) != state->enabled) {
+		clk_div = PWM_BASE_CLK_MHZ * state->period /
+			  (256 * NSEC_PER_MHZ);
+		/* clk_div 1 - 128, maps to register values 0-127 */
+		if (clk_div > 0)
+			clk_div--;
+
+		pwm_output_enable = state->enabled ? PWM_OUTPUT_ENABLE : 0;
+
+		err = regmap_write(crc_pwm->regmap, PWM0_CLK_DIV,
+				   clk_div | pwm_output_enable);
+		if (err) {
+			dev_err(dev, "Error writing PWM0_CLK_DIV %d\n", err);
+			return err;
+		}
+	}
+
+	if (!pwm_is_enabled(pwm) && state->enabled) {
+		err = regmap_write(crc_pwm->regmap, BACKLIGHT_EN, 1);
+		if (err) {
+			dev_err(dev, "Error writing BACKLIGHT_EN %d\n", err);
+			return err;
+		}
+	}
 
 	return 0;
 }
 
 static const struct pwm_ops crc_pwm_ops = {
-	.config = crc_pwm_config,
-	.enable = crc_pwm_enable,
-	.disable = crc_pwm_disable,
+	.apply = crc_pwm_apply,
 };
 
 static int crystalcove_pwm_probe(struct platform_device *pdev)
-- 
2.26.2



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