pwm: meson: Move pwm_set_chip_data() to meson_pwm_request()

All existing PWM drivers (except pwm-meson and two other ones) call
pwm_set_chip_data() from their pwm_ops.request() callback. Now that we
can access the struct meson_pwm_channel from struct meson_pwm we can do
the same.

Move the call to pwm_set_chip_data() to meson_pwm_request() and drop the
custom meson_pwm_add_channels(). This makes the implementation
consistent with other drivers and makes it slightly more obvious
thatpwm_get_chip_data() cannot be used from pwm_ops.get_state() (because
that's called by the PWM core before pwm_ops.request()).

No functional changes intended.
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

drivers/pwm/pwm-meson.c

@@ -98,12 +98,16 @@ static inline struct meson_pwm *to_meson_pwm(struct pwm_chip *chip)
 
 static int meson_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
 {
-	struct meson_pwm_channel *channel = pwm_get_chip_data(pwm);
+	struct meson_pwm *meson = to_meson_pwm(chip);
+	struct meson_pwm_channel *channel;
 	struct device *dev = chip->dev;
 	int err;
 
-	if (!channel)
-		return -ENODEV;
+	channel = pwm_get_chip_data(pwm);
+	if (channel)
+		return 0;
+
+	channel = &meson->channels[pwm->hwpwm];
 
 	if (channel->clk_parent) {
 		err = clk_set_parent(channel->clk, channel->clk_parent);
@@ -124,7 +128,7 @@ static int meson_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
 
 	chip->ops->get_state(chip, pwm, &channel->state);
 
-	return 0;
+	return pwm_set_chip_data(pwm, channel);
 }
 
 static void meson_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
@@ -469,14 +473,6 @@ static int meson_pwm_init_channels(struct meson_pwm *meson)
 	return 0;
 }
 
-static void meson_pwm_add_channels(struct meson_pwm *meson)
-{
-	unsigned int i;
-
-	for (i = 0; i < meson->chip.npwm; i++)
-		pwm_set_chip_data(&meson->chip.pwms[i], &meson->channels[i]);
-}
-
 static int meson_pwm_probe(struct platform_device *pdev)
 {
 	struct meson_pwm *meson;
@@ -512,8 +508,6 @@ static int meson_pwm_probe(struct platform_device *pdev)
 		return err;
 	}
 
-	meson_pwm_add_channels(meson);
-
 	platform_set_drvdata(pdev, meson);
 
 	return 0;