[PATCH 6.12 029/337] ASoC: max98095: fix missing IS_ERR() before PTR_ERR() on mclk lookup

6.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Uday Khare <[email protected]>

[ Upstream commit 317e21532e6ffa1de026bdbce5ba98e1b70ca5c6 ]

In max98095_probe(), the -EPROBE_DEFER check after devm_clk_get() is
broken due to a missing IS_ERR() guard.

The code intends to return -EPROBE_DEFER only when the clock lookup
fails with that specific error.  However, without IS_ERR() the check:

    if (PTR_ERR(max98095->mclk) == -EPROBE_DEFER)

is called unconditionally, including when devm_clk_get() succeeds and
returns a valid pointer.  Calling PTR_ERR() on a valid pointer
reinterprets its address as a signed long; the result is arbitrary
and is almost never equal to -EPROBE_DEFER, so the check silently
does nothing in the success case.  When devm_clk_get() fails with
any error other than -EPROBE_DEFER the check is also skipped, leaving
max98095->mclk holding an error pointer with no indication to the caller.

This means a deferred probe will never actually be triggered for this
device, and any non-EPROBE_DEFER clock error is silently swallowed with
the error pointer left in the mclk field.

Fix this by adding the missing IS_ERR() guard around the PTR_ERR() call,
matching the pattern already used in the sibling max98088 and wm8960
drivers.

Fixes: e3048c3d2be5 ("ASoC: max98095: Add master clock handling")
Signed-off-by: Uday Khare <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Mark Brown <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
---
 sound/soc/codecs/max98095.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/sound/soc/codecs/max98095.c b/sound/soc/codecs/max98095.c
index 7e525d49328d2..3b37f4c4235e6 100644
--- a/sound/soc/codecs/max98095.c
+++ b/sound/soc/codecs/max98095.c
@@ -1984,8 +1984,9 @@ static int max98095_probe(struct snd_soc_component *component)
 	int ret = 0;
 
 	max98095->mclk = devm_clk_get(component->dev, "mclk");
-	if (PTR_ERR(max98095->mclk) == -EPROBE_DEFER)
-		return -EPROBE_DEFER;
+	if (IS_ERR(max98095->mclk))
+		if (PTR_ERR(max98095->mclk) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
 
 	/* reset the codec, the DSP core, and disable all interrupts */
 	max98095_reset(component);
-- 
2.53.0