[PATCH v2 2/2] ASoC: adau1372: Fix clock leak on PLL lock failure

[Jihed Chaibi]

adau1372_enable_pll() was a void function that logged a dev_err() on
PLL lock timeout but did not propagate the error. As a result,
adau1372_set_power() would continue with adau1372->enabled set to true
despite the PLL being unlocked, and the mclk left enabled with no
corresponding disable on the error path.

Convert adau1372_enable_pll() to return int, using -ETIMEDOUT on lock
timeout and propagating regmap errors directly. In adau1372_set_power(),
check the return value and unwind in reverse order: restore regcache to
cache-only mode, reassert GPIO power-down, and disable the clock before
returning the error.

Signed-off-by: Jihed Chaibi <jihed.chaibi.dev@xxxxxxxxx>
---
Changes in v2:
- Also unwind regcache and GPIO power-down state on PLL lock failure,
  as noted by Mark Brown.

 sound/soc/codecs/adau1372.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/sound/soc/codecs/adau1372.c b/sound/soc/codecs/adau1372.c
index 6345342218d6..e3eba241bdf7 100644
--- a/sound/soc/codecs/adau1372.c
+++ b/sound/soc/codecs/adau1372.c
@@ -762,7 +762,7 @@ static int adau1372_startup(struct snd_pcm_substream *substream, struct snd_soc_
 	return 0;
 }

-static void adau1372_enable_pll(struct adau1372 *adau1372)
+static int adau1372_enable_pll(struct adau1372 *adau1372)
 {
 	unsigned int val, timeout = 0;
 	int ret;
@@ -778,8 +778,12 @@ static void adau1372_enable_pll(struct adau1372 *adau1372)
 		timeout++;
 	} while (!(val & 1) && timeout < 3);

-	if (ret < 0 || !(val & 1))
+	if (ret < 0 || !(val & 1)) {
 		dev_err(adau1372->dev, "Failed to lock PLL\n");
+		return ret < 0 ? ret : -ETIMEDOUT;
+	}
+
+	return 0;
 }

 static int adau1372_set_power(struct adau1372 *adau1372, bool enable)
@@ -807,7 +811,14 @@ static int adau1372_set_power(struct adau1372 *adau1372, bool enable)
 		 * accessed.
 		 */
 		if (adau1372->use_pll) {
-			adau1372_enable_pll(adau1372);
+			ret = adau1372_enable_pll(adau1372);
+			if (ret) {
+				regcache_cache_only(adau1372->regmap, true);
+				if (adau1372->pd_gpio)
+					gpiod_set_value(adau1372->pd_gpio, 1);
+				clk_disable_unprepare(adau1372->mclk);
+				return ret;
+			}
 			clk_ctrl |= ADAU1372_CLK_CTRL_CLKSRC;
 		}

--
2.47.3