[PATCH] pinctrl: meson: amlogic-a4: fix gpio output glitch

[PATCH] pinctrl: meson: amlogic-a4: fix gpio output glitch

[Xianwei Zhao]

When the system transitions from bootloader to kernel, the GPIO is
expected to keep driving high.

However, the Linux kernel first configures the pin direction and then
sets the output value. This may cause a brief low-level glitch on the
GPIO line, which can be problematic for regulator control.

By configuring the output value before switching the pin direction to
output, the glitch can be avoided.

This commit fixes the issue by swapping the configuration order.

Fixes: 6e9be3abb78c ("pinctrl: Add driver support for Amlogic SoCs")
Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
---
fix one issue when set gpio line high.
---
 drivers/pinctrl/meson/pinctrl-amlogic-a4.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/pinctrl/meson/pinctrl-amlogic-a4.c b/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
index 35d27626a336..1bd58fbbd26a 100644
--- a/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
+++ b/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
@@ -548,11 +548,11 @@ static int aml_pinconf_set_output_drive(struct aml_pinctrl *info,
 {
 	int ret;
 
-	ret = aml_pinconf_set_output(info, pin, true);
+	ret = aml_pinconf_set_drive(info, pin, high);
 	if (ret)
 		return ret;
 
-	return aml_pinconf_set_drive(info, pin, high);
+	return aml_pinconf_set_output(info, pin, true);
 }
 
 static int aml_pinconf_set(struct pinctrl_dev *pcdev, unsigned int pin,
@@ -921,15 +921,14 @@ static int aml_gpio_direction_output(struct gpio_chip *chip, unsigned int gpio,
 	unsigned int bit, reg;
 	int ret;
 
-	aml_gpio_calc_reg_and_bit(bank, AML_REG_DIR, gpio, &reg, &bit);
-	ret = regmap_update_bits(bank->reg_gpio, reg, BIT(bit), 0);
+	aml_gpio_calc_reg_and_bit(bank, AML_REG_OUT, gpio, &reg, &bit);
+	ret = regmap_update_bits(bank->reg_gpio, reg, BIT(bit),
+				 value ? BIT(bit) : 0);
 	if (ret < 0)
 		return ret;
 
-	aml_gpio_calc_reg_and_bit(bank, AML_REG_OUT, gpio, &reg, &bit);
-
-	return regmap_update_bits(bank->reg_gpio, reg, BIT(bit),
-				  value ? BIT(bit) : 0);
+	aml_gpio_calc_reg_and_bit(bank, AML_REG_DIR, gpio, &reg, &bit);
+	return regmap_update_bits(bank->reg_gpio, reg, BIT(bit), 0);
 }
 
 static int aml_gpio_set(struct gpio_chip *chip, unsigned int gpio, int value)

---
base-commit: 73d4991a6949eedb51e442d4e81415017d85975b
change-id: 20260518-fix-set-value-glitch-f43cd366c295

Best regards,
-- 
Xianwei Zhao <xianwei.zhao@amlogic.com>

[PATCH] pinctrl: meson: amlogic-a4: fix gpio output glitch

[Xianwei Zhao via B4 Relay]

From: Xianwei Zhao <xianwei.zhao@amlogic.com>

When the system transitions from bootloader to kernel, the GPIO is
expected to keep driving high.

However, the Linux kernel first configures the pin direction and then
sets the output value. This may cause a brief low-level glitch on the
GPIO line, which can be problematic for regulator control.

By configuring the output value before switching the pin direction to
output, the glitch can be avoided.

This commit fixes the issue by swapping the configuration order.

Fixes: 6e9be3abb78c ("pinctrl: Add driver support for Amlogic SoCs")
Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
---
fix one issue when set gpio line high.
---
 drivers/pinctrl/meson/pinctrl-amlogic-a4.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/pinctrl/meson/pinctrl-amlogic-a4.c b/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
index 35d27626a336..1bd58fbbd26a 100644
--- a/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
+++ b/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
@@ -548,11 +548,11 @@ static int aml_pinconf_set_output_drive(struct aml_pinctrl *info,
 {
 	int ret;
 
-	ret = aml_pinconf_set_output(info, pin, true);
+	ret = aml_pinconf_set_drive(info, pin, high);
 	if (ret)
 		return ret;
 
-	return aml_pinconf_set_drive(info, pin, high);
+	return aml_pinconf_set_output(info, pin, true);
 }
 
 static int aml_pinconf_set(struct pinctrl_dev *pcdev, unsigned int pin,
@@ -921,15 +921,14 @@ static int aml_gpio_direction_output(struct gpio_chip *chip, unsigned int gpio,
 	unsigned int bit, reg;
 	int ret;
 
-	aml_gpio_calc_reg_and_bit(bank, AML_REG_DIR, gpio, &reg, &bit);
-	ret = regmap_update_bits(bank->reg_gpio, reg, BIT(bit), 0);
+	aml_gpio_calc_reg_and_bit(bank, AML_REG_OUT, gpio, &reg, &bit);
+	ret = regmap_update_bits(bank->reg_gpio, reg, BIT(bit),
+				 value ? BIT(bit) : 0);
 	if (ret < 0)
 		return ret;
 
-	aml_gpio_calc_reg_and_bit(bank, AML_REG_OUT, gpio, &reg, &bit);
-
-	return regmap_update_bits(bank->reg_gpio, reg, BIT(bit),
-				  value ? BIT(bit) : 0);
+	aml_gpio_calc_reg_and_bit(bank, AML_REG_DIR, gpio, &reg, &bit);
+	return regmap_update_bits(bank->reg_gpio, reg, BIT(bit), 0);
 }
 
 static int aml_gpio_set(struct gpio_chip *chip, unsigned int gpio, int value)

---
base-commit: 73d4991a6949eedb51e442d4e81415017d85975b
change-id: 20260518-fix-set-value-glitch-f43cd366c295

Best regards,
-- 
Xianwei Zhao <xianwei.zhao@amlogic.com>



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[PATCH] pinctrl: meson: amlogic-a4: fix gpio output glitch

[Xianwei Zhao via B4 Relay]

From: Xianwei Zhao <xianwei.zhao@amlogic.com>

When the system transitions from bootloader to kernel, the GPIO is
expected to keep driving high.

However, the Linux kernel first configures the pin direction and then
sets the output value. This may cause a brief low-level glitch on the
GPIO line, which can be problematic for regulator control.

By configuring the output value before switching the pin direction to
output, the glitch can be avoided.

This commit fixes the issue by swapping the configuration order.

Fixes: 6e9be3abb78c ("pinctrl: Add driver support for Amlogic SoCs")
Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
---
fix one issue when set gpio line high.
---
 drivers/pinctrl/meson/pinctrl-amlogic-a4.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/pinctrl/meson/pinctrl-amlogic-a4.c b/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
index 35d27626a336..1bd58fbbd26a 100644
--- a/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
+++ b/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
@@ -548,11 +548,11 @@ static int aml_pinconf_set_output_drive(struct aml_pinctrl *info,
 {
 	int ret;
 
-	ret = aml_pinconf_set_output(info, pin, true);
+	ret = aml_pinconf_set_drive(info, pin, high);
 	if (ret)
 		return ret;
 
-	return aml_pinconf_set_drive(info, pin, high);
+	return aml_pinconf_set_output(info, pin, true);
 }
 
 static int aml_pinconf_set(struct pinctrl_dev *pcdev, unsigned int pin,
@@ -921,15 +921,14 @@ static int aml_gpio_direction_output(struct gpio_chip *chip, unsigned int gpio,
 	unsigned int bit, reg;
 	int ret;
 
-	aml_gpio_calc_reg_and_bit(bank, AML_REG_DIR, gpio, &reg, &bit);
-	ret = regmap_update_bits(bank->reg_gpio, reg, BIT(bit), 0);
+	aml_gpio_calc_reg_and_bit(bank, AML_REG_OUT, gpio, &reg, &bit);
+	ret = regmap_update_bits(bank->reg_gpio, reg, BIT(bit),
+				 value ? BIT(bit) : 0);
 	if (ret < 0)
 		return ret;
 
-	aml_gpio_calc_reg_and_bit(bank, AML_REG_OUT, gpio, &reg, &bit);
-
-	return regmap_update_bits(bank->reg_gpio, reg, BIT(bit),
-				  value ? BIT(bit) : 0);
+	aml_gpio_calc_reg_and_bit(bank, AML_REG_DIR, gpio, &reg, &bit);
+	return regmap_update_bits(bank->reg_gpio, reg, BIT(bit), 0);
 }
 
 static int aml_gpio_set(struct gpio_chip *chip, unsigned int gpio, int value)

---
base-commit: 73d4991a6949eedb51e442d4e81415017d85975b
change-id: 20260518-fix-set-value-glitch-f43cd366c295

Best regards,
-- 
Xianwei Zhao <xianwei.zhao@amlogic.com>

Re: [PATCH] pinctrl: meson: amlogic-a4: fix gpio output glitch

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [High] Incomplete fix: The GPIO output glitch bug is identically present in the core `pinctrl-meson.c` driver, leaving other Amlogic SoCs vulnerable.
- [High] AA deadlock in `aml_pinconf_set_*` functions triggerable from userspace via GPIO character device.
--

commit 91d93a06a0e9681b94621504af7968b8a6f4f155
Author: Xianwei Zhao <xianwei.zhao@amlogic.com>

pinctrl: meson: amlogic-a4: fix gpio output glitch

This commit fixes a brief low-level glitch on GPIO lines during the
transition from bootloader to kernel. It does this by swapping the
configuration order to set the output value before switching the pin
direction to output.

> diff --git a/drivers/pinctrl/meson/pinctrl-amlogic-a4.c b/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
> index 35d27626a336b..1bd58fbbd26ac 100644
> --- a/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
> +++ b/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
> @@ -548,11 +548,11 @@ static int aml_pinconf_set_output_drive(struct aml_pinctrl *info,
>  {
>  	int ret;
>  
> -	ret = aml_pinconf_set_output(info, pin, true);
> +	ret = aml_pinconf_set_drive(info, pin, high);

Does this call chain trigger an AA deadlock when configured at runtime?

When a GPIO line's configuration is changed from userspace (for example, via
the GPIO_V2_LINE_SET_CONFIG_IOCTL), the core pinctrl_gpio_set_config()
function acquires pctldev->mutex before invoking the .pin_config_set callback.

If aml_pinconf_set_drive() calls aml_pinconf_set_gpio_bit(), and that function
still uses pinctrl_find_gpio_range_from_pin(), it will attempt to acquire the
same pctldev->mutex.

A previous commit fixed a similar deadlock for the _get functions by switching
to pinctrl_find_gpio_range_from_pin_nolock(). Do the _set functions need the
same update?

Additionally, while this resolves the glitch for the amlogic-a4 driver, does
the core pinctrl-meson.c driver have the same issue? Looking at
meson_pinconf_set_output_drive() in the core driver, it appears to still
call meson_pinconf_set_output() before meson_pinconf_set_drive(). Could
other Amlogic SoCs be vulnerable to the same regulator control glitch
unless the order is swapped there as well?

>  	if (ret)
>  		return ret;
>  
> -	return aml_pinconf_set_drive(info, pin, high);
> +	return aml_pinconf_set_output(info, pin, true);
>  }

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260518-fix-set-value-glitch-v1-1-d350732dc934@amlogic.com?part=1

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Re: [PATCH] pinctrl: meson: amlogic-a4: fix gpio output glitch

[Neil Armstrong]

On 5/18/26 10:26, Xianwei Zhao via B4 Relay wrote:
> From: Xianwei Zhao <xianwei.zhao@amlogic.com>
> 
> When the system transitions from bootloader to kernel, the GPIO is
> expected to keep driving high.
> 
> However, the Linux kernel first configures the pin direction and then
> sets the output value. This may cause a brief low-level glitch on the
> GPIO line, which can be problematic for regulator control.
> 
> By configuring the output value before switching the pin direction to
> output, the glitch can be avoided.
> 
> This commit fixes the issue by swapping the configuration order.
> 
> Fixes: 6e9be3abb78c ("pinctrl: Add driver support for Amlogic SoCs")
> Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
> ---
> fix one issue when set gpio line high.
> ---
>   drivers/pinctrl/meson/pinctrl-amlogic-a4.c | 15 +++++++--------
>   1 file changed, 7 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/pinctrl/meson/pinctrl-amlogic-a4.c b/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
> index 35d27626a336..1bd58fbbd26a 100644
> --- a/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
> +++ b/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
> @@ -548,11 +548,11 @@ static int aml_pinconf_set_output_drive(struct aml_pinctrl *info,
>   {
>   	int ret;
>   
> -	ret = aml_pinconf_set_output(info, pin, true);
> +	ret = aml_pinconf_set_drive(info, pin, high);
>   	if (ret)
>   		return ret;
>   
> -	return aml_pinconf_set_drive(info, pin, high);
> +	return aml_pinconf_set_output(info, pin, true);
>   }
>   
>   static int aml_pinconf_set(struct pinctrl_dev *pcdev, unsigned int pin,
> @@ -921,15 +921,14 @@ static int aml_gpio_direction_output(struct gpio_chip *chip, unsigned int gpio,
>   	unsigned int bit, reg;
>   	int ret;
>   
> -	aml_gpio_calc_reg_and_bit(bank, AML_REG_DIR, gpio, &reg, &bit);
> -	ret = regmap_update_bits(bank->reg_gpio, reg, BIT(bit), 0);
> +	aml_gpio_calc_reg_and_bit(bank, AML_REG_OUT, gpio, &reg, &bit);
> +	ret = regmap_update_bits(bank->reg_gpio, reg, BIT(bit),
> +				 value ? BIT(bit) : 0);
>   	if (ret < 0)
>   		return ret;
>   
> -	aml_gpio_calc_reg_and_bit(bank, AML_REG_OUT, gpio, &reg, &bit);
> -
> -	return regmap_update_bits(bank->reg_gpio, reg, BIT(bit),
> -				  value ? BIT(bit) : 0);
> +	aml_gpio_calc_reg_and_bit(bank, AML_REG_DIR, gpio, &reg, &bit);
> +	return regmap_update_bits(bank->reg_gpio, reg, BIT(bit), 0);
>   }
>   
>   static int aml_gpio_set(struct gpio_chip *chip, unsigned int gpio, int value)
> 
> ---
> base-commit: 73d4991a6949eedb51e442d4e81415017d85975b
> change-id: 20260518-fix-set-value-glitch-f43cd366c295
> 
> Best regards,

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>

Thanks,
Neil

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Re: [PATCH] pinctrl: meson: amlogic-a4: fix gpio output glitch

[Neil Armstrong]

On 5/18/26 10:26, Xianwei Zhao via B4 Relay wrote:
> From: Xianwei Zhao <xianwei.zhao@amlogic.com>
> 
> When the system transitions from bootloader to kernel, the GPIO is
> expected to keep driving high.
> 
> However, the Linux kernel first configures the pin direction and then
> sets the output value. This may cause a brief low-level glitch on the
> GPIO line, which can be problematic for regulator control.
> 
> By configuring the output value before switching the pin direction to
> output, the glitch can be avoided.
> 
> This commit fixes the issue by swapping the configuration order.
> 
> Fixes: 6e9be3abb78c ("pinctrl: Add driver support for Amlogic SoCs")
> Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
> ---
> fix one issue when set gpio line high.
> ---
>   drivers/pinctrl/meson/pinctrl-amlogic-a4.c | 15 +++++++--------
>   1 file changed, 7 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/pinctrl/meson/pinctrl-amlogic-a4.c b/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
> index 35d27626a336..1bd58fbbd26a 100644
> --- a/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
> +++ b/drivers/pinctrl/meson/pinctrl-amlogic-a4.c
> @@ -548,11 +548,11 @@ static int aml_pinconf_set_output_drive(struct aml_pinctrl *info,
>   {
>   	int ret;
>   
> -	ret = aml_pinconf_set_output(info, pin, true);
> +	ret = aml_pinconf_set_drive(info, pin, high);
>   	if (ret)
>   		return ret;
>   
> -	return aml_pinconf_set_drive(info, pin, high);
> +	return aml_pinconf_set_output(info, pin, true);
>   }
>   
>   static int aml_pinconf_set(struct pinctrl_dev *pcdev, unsigned int pin,
> @@ -921,15 +921,14 @@ static int aml_gpio_direction_output(struct gpio_chip *chip, unsigned int gpio,
>   	unsigned int bit, reg;
>   	int ret;
>   
> -	aml_gpio_calc_reg_and_bit(bank, AML_REG_DIR, gpio, &reg, &bit);
> -	ret = regmap_update_bits(bank->reg_gpio, reg, BIT(bit), 0);
> +	aml_gpio_calc_reg_and_bit(bank, AML_REG_OUT, gpio, &reg, &bit);
> +	ret = regmap_update_bits(bank->reg_gpio, reg, BIT(bit),
> +				 value ? BIT(bit) : 0);
>   	if (ret < 0)
>   		return ret;
>   
> -	aml_gpio_calc_reg_and_bit(bank, AML_REG_OUT, gpio, &reg, &bit);
> -
> -	return regmap_update_bits(bank->reg_gpio, reg, BIT(bit),
> -				  value ? BIT(bit) : 0);
> +	aml_gpio_calc_reg_and_bit(bank, AML_REG_DIR, gpio, &reg, &bit);
> +	return regmap_update_bits(bank->reg_gpio, reg, BIT(bit), 0);
>   }
>   
>   static int aml_gpio_set(struct gpio_chip *chip, unsigned int gpio, int value)
> 
> ---
> base-commit: 73d4991a6949eedb51e442d4e81415017d85975b
> change-id: 20260518-fix-set-value-glitch-f43cd366c295
> 
> Best regards,

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>

Thanks,
Neil

Re: [PATCH] pinctrl: meson: amlogic-a4: fix gpio output glitch

[Linus Walleij]

On Mon, May 18, 2026 at 10:26 AM Xianwei Zhao via B4 Relay
<devnull+xianwei.zhao.amlogic.com@kernel.org> wrote:

> From: Xianwei Zhao <xianwei.zhao@amlogic.com>
>
> When the system transitions from bootloader to kernel, the GPIO is
> expected to keep driving high.
>
> However, the Linux kernel first configures the pin direction and then
> sets the output value. This may cause a brief low-level glitch on the
> GPIO line, which can be problematic for regulator control.
>
> By configuring the output value before switching the pin direction to
> output, the glitch can be avoided.
>
> This commit fixes the issue by swapping the configuration order.
>
> Fixes: 6e9be3abb78c ("pinctrl: Add driver support for Amlogic SoCs")
> Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>

Is this a regression? I.e. does it cause problems on a supported
system with mainline?

Linus (the big penguin) is unhappy with too many non-critical fixes
so I wanna check this before this goes into fixes.

Yours,
Linus Walleij

Re: [PATCH] pinctrl: meson: amlogic-a4: fix gpio output glitch

[Linus Walleij]

On Mon, May 18, 2026 at 10:26 AM Xianwei Zhao via B4 Relay
<devnull+xianwei.zhao.amlogic.com@kernel.org> wrote:

> From: Xianwei Zhao <xianwei.zhao@amlogic.com>
>
> When the system transitions from bootloader to kernel, the GPIO is
> expected to keep driving high.
>
> However, the Linux kernel first configures the pin direction and then
> sets the output value. This may cause a brief low-level glitch on the
> GPIO line, which can be problematic for regulator control.
>
> By configuring the output value before switching the pin direction to
> output, the glitch can be avoided.
>
> This commit fixes the issue by swapping the configuration order.
>
> Fixes: 6e9be3abb78c ("pinctrl: Add driver support for Amlogic SoCs")
> Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>

Is this a regression? I.e. does it cause problems on a supported
system with mainline?

Linus (the big penguin) is unhappy with too many non-critical fixes
so I wanna check this before this goes into fixes.

Yours,
Linus Walleij

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Re: [PATCH] pinctrl: meson: amlogic-a4: fix gpio output glitch

[Xianwei Zhao]

Hi Linus,
    Thanks for your review.

On 2026/5/25 16:34, Linus Walleij wrote:
> On Mon, May 18, 2026 at 10:26 AM Xianwei Zhao via B4 Relay
> <devnull+xianwei.zhao.amlogic.com@kernel.org>  wrote:
> 
>> From: Xianwei Zhao<xianwei.zhao@amlogic.com>
>>
>> When the system transitions from bootloader to kernel, the GPIO is
>> expected to keep driving high.
>>
>> However, the Linux kernel first configures the pin direction and then
>> sets the output value. This may cause a brief low-level glitch on the
>> GPIO line, which can be problematic for regulator control.
>>
>> By configuring the output value before switching the pin direction to
>> output, the glitch can be avoided.
>>
>> This commit fixes the issue by swapping the configuration order.
>>
>> Fixes: 6e9be3abb78c ("pinctrl: Add driver support for Amlogic SoCs")
>> Signed-off-by: Xianwei Zhao<xianwei.zhao@amlogic.com>
> Is this a regression? I.e. does it cause problems on a supported
> system with mainline?
> 
> Linus (the big penguin) is unhappy with too many non-critical fixes
> so I wanna check this before this goes into fixes.
> 

The issue only occurs when the critical power supply uses GPIO control. 
Otherwise, it is not significant.

> Yours,
> Linus Walleij

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Re: [PATCH] pinctrl: meson: amlogic-a4: fix gpio output glitch

[Xianwei Zhao]

Hi Linus,
    Thanks for your review.

On 2026/5/25 16:34, Linus Walleij wrote:
> On Mon, May 18, 2026 at 10:26 AM Xianwei Zhao via B4 Relay
> <devnull+xianwei.zhao.amlogic.com@kernel.org>  wrote:
> 
>> From: Xianwei Zhao<xianwei.zhao@amlogic.com>
>>
>> When the system transitions from bootloader to kernel, the GPIO is
>> expected to keep driving high.
>>
>> However, the Linux kernel first configures the pin direction and then
>> sets the output value. This may cause a brief low-level glitch on the
>> GPIO line, which can be problematic for regulator control.
>>
>> By configuring the output value before switching the pin direction to
>> output, the glitch can be avoided.
>>
>> This commit fixes the issue by swapping the configuration order.
>>
>> Fixes: 6e9be3abb78c ("pinctrl: Add driver support for Amlogic SoCs")
>> Signed-off-by: Xianwei Zhao<xianwei.zhao@amlogic.com>
> Is this a regression? I.e. does it cause problems on a supported
> system with mainline?
> 
> Linus (the big penguin) is unhappy with too many non-critical fixes
> so I wanna check this before this goes into fixes.
> 

The issue only occurs when the critical power supply uses GPIO control. 
Otherwise, it is not significant.

> Yours,
> Linus Walleij

Re: [PATCH] pinctrl: meson: amlogic-a4: fix gpio output glitch

[Linus Walleij]

On Mon, May 18, 2026 at 10:26 AM Xianwei Zhao via B4 Relay
<devnull+xianwei.zhao.amlogic.com@kernel.org> wrote:

> From: Xianwei Zhao <xianwei.zhao@amlogic.com>
>
> When the system transitions from bootloader to kernel, the GPIO is
> expected to keep driving high.
>
> However, the Linux kernel first configures the pin direction and then
> sets the output value. This may cause a brief low-level glitch on the
> GPIO line, which can be problematic for regulator control.
>
> By configuring the output value before switching the pin direction to
> output, the glitch can be avoided.
>
> This commit fixes the issue by swapping the configuration order.
>
> Fixes: 6e9be3abb78c ("pinctrl: Add driver support for Amlogic SoCs")
> Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>

Patch applied as non-critical fix based on my gut feeling.

Yours,
Linus Walleij

Re: [PATCH] pinctrl: meson: amlogic-a4: fix gpio output glitch

[Linus Walleij]

On Mon, May 18, 2026 at 10:26 AM Xianwei Zhao via B4 Relay
<devnull+xianwei.zhao.amlogic.com@kernel.org> wrote:

> From: Xianwei Zhao <xianwei.zhao@amlogic.com>
>
> When the system transitions from bootloader to kernel, the GPIO is
> expected to keep driving high.
>
> However, the Linux kernel first configures the pin direction and then
> sets the output value. This may cause a brief low-level glitch on the
> GPIO line, which can be problematic for regulator control.
>
> By configuring the output value before switching the pin direction to
> output, the glitch can be avoided.
>
> This commit fixes the issue by swapping the configuration order.
>
> Fixes: 6e9be3abb78c ("pinctrl: Add driver support for Amlogic SoCs")
> Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>

Patch applied as non-critical fix based on my gut feeling.

Yours,
Linus Walleij

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