Re: [PATCH v3 06/10] leds: pca995x: Add support for reset GPIO

[Lee Jones <lee@kernel.org>]

On Tue, 22 Sep 2026, Nora Schiffer wrote:

> The PCA9952/9955B/9956B have a reset pin. Use it to reset the LED driver
> if provided in the Device Tree.
> 
> Signed-off-by: Nora Schiffer <nora.schiffer@ew.tq-group.com>
> ---
>  drivers/leds/leds-pca995x.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/drivers/leds/leds-pca995x.c b/drivers/leds/leds-pca995x.c
> index e6122b33451ed..b528b2b4990a7 100644
> --- a/drivers/leds/leds-pca995x.c
> +++ b/drivers/leds/leds-pca995x.c
> @@ -8,6 +8,8 @@
>   * Copyright 2023 Marek Vasut
>   */
>  
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
>  #include <linux/i2c.h>
>  #include <linux/leds.h>
>  #include <linux/module.h>
> @@ -121,6 +123,7 @@ static int pca995x_probe(struct i2c_client *client)
>  	struct fwnode_handle *led_fwnodes[PCA995X_MAX_OUTPUTS] = { 0 };
>  	struct device *dev = &client->dev;
>  	const struct pca995x_chipdef *chipdef;
> +	struct gpio_desc *reset_gpio;
>  	struct pca995x_chip *chip;
>  	struct pca995x_led *led;
>  	int i, reg, ret;
> @@ -130,6 +133,16 @@ static int pca995x_probe(struct i2c_client *client)
>  	if (!dev_fwnode(dev))
>  		return -ENODEV;
>  
> +	reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
> +	if (IS_ERR(reset_gpio))
> +		return dev_err_probe(dev, PTR_ERR(reset_gpio),
> +				     "failed to request reset GPIO\n");
> +	if (reset_gpio) {
> +		udelay(3);

It's strange to see delays _before_ actions.

What are you delaying for exactly?

> +		gpiod_set_value_cansleep(reset_gpio, 0);
> +		usleep_range(1500, 1600);
> +	}
> +
>  	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
>  	if (!chip)
>  		return -ENOMEM;
> -- 
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> 

-- 
Lee Jones