pwm: stmpe: Silence duplicate error messages

stmpe_reg_read() and stmpe_reg_write() already emit error messages when
they fail. So the extra error messages in the pwm driver are only little
useful. They are useful in some situation, as they give a bit of context
to the failing register write. So don't remove them but degrade them to
dev_dbg().
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

drivers/pwm/pwm-stmpe.c

@@ -44,7 +44,7 @@ static int stmpe_24xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 
 	ret = stmpe_reg_read(stmpe_pwm->stmpe, STMPE24XX_PWMCS);
 	if (ret < 0) {
-		dev_err(chip->dev, "error reading PWM#%u control\n",
+		dev_dbg(chip->dev, "error reading PWM#%u control\n",
 			pwm->hwpwm);
 		return ret;
 	}
@@ -53,7 +53,7 @@ static int stmpe_24xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 
 	ret = stmpe_reg_write(stmpe_pwm->stmpe, STMPE24XX_PWMCS, value);
 	if (ret) {
-		dev_err(chip->dev, "error writing PWM#%u control\n",
+		dev_dbg(chip->dev, "error writing PWM#%u control\n",
 			pwm->hwpwm);
 		return ret;
 	}
@@ -70,7 +70,7 @@ static int stmpe_24xx_pwm_disable(struct pwm_chip *chip,
 
 	ret = stmpe_reg_read(stmpe_pwm->stmpe, STMPE24XX_PWMCS);
 	if (ret < 0) {
-		dev_err(chip->dev, "error reading PWM#%u control\n",
+		dev_dbg(chip->dev, "error reading PWM#%u control\n",
 			pwm->hwpwm);
 		return ret;
 	}
@@ -79,7 +79,7 @@ static int stmpe_24xx_pwm_disable(struct pwm_chip *chip,
 
 	ret = stmpe_reg_write(stmpe_pwm->stmpe, STMPE24XX_PWMCS, value);
 	if (ret)
-		dev_err(chip->dev, "error writing PWM#%u control\n",
+		dev_dbg(chip->dev, "error writing PWM#%u control\n",
 			pwm->hwpwm);
 	return ret;
 }
@@ -233,7 +233,7 @@ static int stmpe_24xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 
 		ret = stmpe_reg_write(stmpe_pwm->stmpe, offset, value);
 		if (ret) {
-			dev_err(chip->dev, "error writing register %02x: %d\n",
+			dev_dbg(chip->dev, "error writing register %02x: %d\n",
 				offset, ret);
 			return ret;
 		}
@@ -242,7 +242,7 @@ static int stmpe_24xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 
 		ret = stmpe_reg_write(stmpe_pwm->stmpe, offset, value);
 		if (ret) {
-			dev_err(chip->dev, "error writing register %02x: %d\n",
+			dev_dbg(chip->dev, "error writing register %02x: %d\n",
 				offset, ret);
 			return ret;
 		}