From: wangdicheng <wangdicheng@kylinos.cn>

In aw88395_i2c_probe(), if `devm_gpiod_get_optional()` fails, it returns
an ERR_PTR() error pointer. The current code only prints a message and
continues execution, leaving `aw88395->reset_gpio` as an invalid pointer.

Later, in `aw88395_hw_reset()`, this invalid pointer is passed to
`gpiod_set_value_cansleep()`, which dereferences it and causes a kernel
panic.

For optional GPIOs, `devm_gpiod_get_optional()` returns NULL if the GPIO
is not defined in the DT, which is safe. If it returns an ERR_PTR, it
means a real error occurred (e.g., -EPROBE_DEFER) and the probe must be
aborted.

Also, since the GPIO is optional, remove the dev_err() log in
aw88395_hw_reset() when the GPIO is missing to match the optional
semantics. This also fixes a potential NULL pointer dereference as
aw_pa is not initialized when aw88395_hw_reset() is called.

Signed-off-by: wangdicheng <wangdicheng@kylinos.cn>
---
v1->v2:
Remove dev_err() in aw88395_hw_reset() to align with optional GPIO
semantics and fix NULL pointer dereference if aw_pa is uninitialized.

 sound/soc/codecs/aw88395/aw88395.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/sound/soc/codecs/aw88395/aw88395.c b/sound/soc/codecs/aw88395/aw88395.c
index 3602b5b9f7d7..dd09bac652f7 100644
--- a/sound/soc/codecs/aw88395/aw88395.c
+++ b/sound/soc/codecs/aw88395/aw88395.c
@@ -456,8 +456,6 @@ static void aw88395_hw_reset(struct aw88395 *aw88395)
 		usleep_range(AW88395_1000_US, AW88395_1000_US + 10);
 		gpiod_set_value_cansleep(aw88395->reset_gpio, 1);
 		usleep_range(AW88395_1000_US, AW88395_1000_US + 10);
-	} else {
-		dev_err(aw88395->aw_pa->dev, "%s failed", __func__);
 	}
 }
 
@@ -522,9 +520,10 @@ static int aw88395_i2c_probe(struct i2c_client *i2c)
 	i2c_set_clientdata(i2c, aw88395);
 
 	aw88395->reset_gpio = devm_gpiod_get_optional(&i2c->dev, "reset", GPIOD_OUT_LOW);
-	if (IS_ERR(aw88395->reset_gpio))
-		dev_info(&i2c->dev, "reset gpio not defined\n");
-
+	if (IS_ERR(aw88395->reset_gpio)) {
+		return dev_err_probe(&i2c->dev, PTR_ERR(aw88395->reset_gpio),
+				"failed to get reset gpio\n");
+	}
 	/* hardware reset */
 	aw88395_hw_reset(aw88395);
 
-- 
2.25.1

On Tue, 28 Apr 2026 10:34:08 +0800, wangdich9700@163.com wrote:
> ASoC: aw88395: Fix kernel panic caused by invalid GPIO error pointer

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-7.1

Thanks!

[1/1] ASoC: aw88395: Fix kernel panic caused by invalid GPIO error pointer
      https://git.kernel.org/broonie/sound/c/241ee17ecb6b

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark