Unverified Commit 241ee17e authored by wangdicheng's avatar wangdicheng Committed by Mark Brown
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ASoC: aw88395: Fix kernel panic caused by invalid GPIO error pointer 



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: default avatarwangdicheng <wangdicheng@kylinos.cn>
Link: https://patch.msgid.link/20260428023408.46420-1-wangdich9700@163.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 8ed33111

sound/soc/codecs/aw88395/aw88395.c

+4 −5
Original line number Diff line number Diff line
@@ -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);