diff mbox series

[v6,1/5] pwm: mtk-disp: adjust the clocks to avoid them mismatch

Message ID 20210724081849.182108-2-jitao.shi@mediatek.com (mailing list archive)
State New, archived
Headers show
Series fix the clks on/off mismatch issue and switch pwm-mtk-disp to atomic APIs | expand

Commit Message

Jitao Shi July 24, 2021, 8:18 a.m. UTC
The clks "main" and "mm" are prepared in .probe() (and
unprepared in .remove()). This results in the clocks being on
during suspend which results in unnecessarily increased power
consumption.

Remove the clock operations from .probe() and .remove().
Add the clk_prepare_enable() in .enable().
Add the clk_disable_unprepare() in .disable().

Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
---
 drivers/pwm/pwm-mtk-disp.c | 72 ++++++++++++++++----------------------
 1 file changed, 31 insertions(+), 41 deletions(-)
diff mbox series

Patch

diff --git a/drivers/pwm/pwm-mtk-disp.c b/drivers/pwm/pwm-mtk-disp.c
index 9b3ba401a3db..3ade525adcc3 100644
--- a/drivers/pwm/pwm-mtk-disp.c
+++ b/drivers/pwm/pwm-mtk-disp.c
@@ -74,6 +74,19 @@  static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	u64 div, rate;
 	int err;
 
+	err = clk_prepare_enable(mdp->clk_main);
+	if (err < 0) {
+		dev_err(chip->dev, "Can't enable mdp->clk_main: %pe\n", ERR_PTR(err));
+		return err;
+	}
+
+	err = clk_prepare_enable(mdp->clk_mm);
+	if (err < 0) {
+		dev_err(chip->dev, "Can't enable mdp->clk_mm: %pe\n", ERR_PTR(err));
+		clk_disable_unprepare(mdp->clk_main);
+		return err;
+	}
+
 	/*
 	 * Find period, high_width and clk_div to suit duty_ns and period_ns.
 	 * Calculate proper div value to keep period value in the bound.
@@ -87,8 +100,11 @@  static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	rate = clk_get_rate(mdp->clk_main);
 	clk_div = div_u64(rate * period_ns, NSEC_PER_SEC) >>
 			  PWM_PERIOD_BIT_WIDTH;
-	if (clk_div > PWM_CLKDIV_MAX)
+	if (clk_div > PWM_CLKDIV_MAX) {
+		clk_disable_unprepare(mdp->clk_mm);
+		clk_disable_unprepare(mdp->clk_main);
 		return -EINVAL;
+	}
 
 	div = NSEC_PER_SEC * (clk_div + 1);
 	period = div64_u64(rate * period_ns, div);
@@ -98,16 +114,6 @@  static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	high_width = div64_u64(rate * duty_ns, div);
 	value = period | (high_width << PWM_HIGH_WIDTH_SHIFT);
 
-	err = clk_enable(mdp->clk_main);
-	if (err < 0)
-		return err;
-
-	err = clk_enable(mdp->clk_mm);
-	if (err < 0) {
-		clk_disable(mdp->clk_main);
-		return err;
-	}
-
 	mtk_disp_pwm_update_bits(mdp, mdp->data->con0,
 				 PWM_CLKDIV_MASK,
 				 clk_div << PWM_CLKDIV_SHIFT);
@@ -124,8 +130,8 @@  static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 					 0x0);
 	}
 
-	clk_disable(mdp->clk_mm);
-	clk_disable(mdp->clk_main);
+	clk_disable_unprepare(mdp->clk_mm);
+	clk_disable_unprepare(mdp->clk_main);
 
 	return 0;
 }
@@ -135,13 +141,16 @@  static int mtk_disp_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 	struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
 	int err;
 
-	err = clk_enable(mdp->clk_main);
-	if (err < 0)
+	err = clk_prepare_enable(mdp->clk_main);
+	if (err < 0) {
+		dev_err(chip->dev, "Can't enable mdp->clk_main: %pe\n", ERR_PTR(err));
 		return err;
+	}
 
-	err = clk_enable(mdp->clk_mm);
+	err = clk_prepare_enable(mdp->clk_mm);
 	if (err < 0) {
-		clk_disable(mdp->clk_main);
+		dev_err(chip->dev, "Can't enable mdp->clk_mm: %pe\n", ERR_PTR(err));
+		clk_disable_unprepare(mdp->clk_main);
 		return err;
 	}
 
@@ -158,8 +167,8 @@  static void mtk_disp_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
 	mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
 				 0x0);
 
-	clk_disable(mdp->clk_mm);
-	clk_disable(mdp->clk_main);
+	clk_disable_unprepare(mdp->clk_mm);
+	clk_disable_unprepare(mdp->clk_main);
 }
 
 static const struct pwm_ops mtk_disp_pwm_ops = {
@@ -192,22 +201,14 @@  static int mtk_disp_pwm_probe(struct platform_device *pdev)
 	if (IS_ERR(mdp->clk_mm))
 		return PTR_ERR(mdp->clk_mm);
 
-	ret = clk_prepare(mdp->clk_main);
-	if (ret < 0)
-		return ret;
-
-	ret = clk_prepare(mdp->clk_mm);
-	if (ret < 0)
-		goto disable_clk_main;
-
 	mdp->chip.dev = &pdev->dev;
 	mdp->chip.ops = &mtk_disp_pwm_ops;
 	mdp->chip.npwm = 1;
 
 	ret = pwmchip_add(&mdp->chip);
 	if (ret < 0) {
-		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
-		goto disable_clk_mm;
+		dev_err(&pdev->dev, "pwmchip_add() failed: %pe\n", ERR_PTR(ret));
+		return ret;
 	}
 
 	platform_set_drvdata(pdev, mdp);
@@ -226,24 +227,13 @@  static int mtk_disp_pwm_probe(struct platform_device *pdev)
 	}
 
 	return 0;
-
-disable_clk_mm:
-	clk_unprepare(mdp->clk_mm);
-disable_clk_main:
-	clk_unprepare(mdp->clk_main);
-	return ret;
 }
 
 static int mtk_disp_pwm_remove(struct platform_device *pdev)
 {
 	struct mtk_disp_pwm *mdp = platform_get_drvdata(pdev);
-	int ret;
-
-	ret = pwmchip_remove(&mdp->chip);
-	clk_unprepare(mdp->clk_mm);
-	clk_unprepare(mdp->clk_main);
 
-	return ret;
+	return pwmchip_remove(&mdp->chip);
 }
 
 static const struct mtk_pwm_data mt2701_pwm_data = {