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From: Lee Jones <lee@kernel.org>
To: Cosmo Chou <chou.cosmo@gmail.com>
Cc: riku.voipio@iki.fi, pavel@kernel.org, linusw@kernel.org,
	brgl@kernel.org, linux-leds@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-gpio@vger.kernel.org,
	cosmo.chou@quantatw.com
Subject: Re: [PATCH] leds: pca9532: Fix inverted GPIO output polarity
Date: Thu, 2 Jul 2026 13:20:44 +0100	[thread overview]
Message-ID: <20260702122044.GM2108533@google.com> (raw)
In-Reply-To: <20260617053934.2122685-1-chou.cosmo@gmail.com>

 n Wed, 17 Jun 2026, Cosmo Chou wrote:

> The pca9532_gpio_set_value() function incorrectly mapped the requested
> value to PCA9532_ON and PCA9532_OFF, inverting the GPIO output polarity.
> A requested logical high (val=1) incorrectly enabled the LED output
> driver, which on this open-drain device pulls the pin low, while a
> requested logical low (val=0) released the pin.
> 
> Correct the mapping so that val=1 yields PCA9532_OFF (pin released /
> high-impedance) and val=0 yields PCA9532_ON (pin driven low).
> 
> pca9532_gpio_direction_input() is also updated to pass val=1 to
> pca9532_gpio_set_value() to align with the corrected polarity mapping,
> ensuring the pin remains not driven when configured as an input.
> 
> Fixes: <3c1ab50d0a31b27bb4e55168f4901dd91e6e5ea4> ("drivers/leds/leds-pca9532.c: add gpio capability")

'Fixes: 3c1ab50d0a31 ("drivers/leds/leds-pca9532.c: add gpio capability")'

> Signed-off-by: Cosmo Chou <chou.cosmo@gmail.com>
> ---
>  drivers/leds/leds-pca9532.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/leds/leds-pca9532.c b/drivers/leds/leds-pca9532.c
> index 0344189bb991..80bf94e699d4 100644
> --- a/drivers/leds/leds-pca9532.c
> +++ b/drivers/leds/leds-pca9532.c
> @@ -325,9 +325,9 @@ static int pca9532_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
>  	struct pca9532_led *led = &data->leds[offset];
>  
>  	if (val)
> -		led->state = PCA9532_ON;
> -	else
>  		led->state = PCA9532_OFF;
> +	else
> +		led->state = PCA9532_ON;
>  
>  	pca9532_setled(led);
>  
> @@ -347,7 +347,7 @@ static int pca9532_gpio_get_value(struct gpio_chip *gc, unsigned offset)
>  static int pca9532_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
>  {
>  	/* To use as input ensure pin is not driven */
> -	pca9532_gpio_set_value(gc, offset, 0);
> +	pca9532_gpio_set_value(gc, offset, 1);
>  
>  	return 0;
>  }
> -- 
> 2.43.0
> 

-- 
Lee Jones

      reply	other threads:[~2026-07-02 12:20 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-06-17  5:39 [PATCH] leds: pca9532: Fix inverted GPIO output polarity Cosmo Chou
2026-07-02 12:20 ` Lee Jones [this message]

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