Re: [PATCH v3 2/2] spi: qcom-geni: Use GPIO to notify master of SPI target activity

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 8/18/26 3:38 PM, Praveen Talari wrote:
> When operating in SPI target mode, the GENI controller relies on an
> external GPIO to notify the SPI master about the target's active state.
> 
> Add support for an optional ready GPIO that is asserted when a target
> transfer begins and deasserted when the transfer completes, is aborted,
> or hits a timeout. This allows the target to explicitly signal its
> availability to the master and ensures the GPIO is released in all error
> and completion paths, preventing the master from observing a stale or
> incorrect target-ready indication.

[...]

> +	if (spi->target && mas->target_gpio)
> +		gpiod_set_value(mas->target_gpio, 0);

FWIW it seems like the gpiod APIs can eat nullptrs

[...]

> @@ -1131,8 +1144,16 @@ static int spi_geni_probe(struct platform_device *pdev)
>  	init_completion(&mas->rx_reset_done);
>  	spin_lock_init(&mas->lock);
>  
> -	if (spi->target)
> +	if (spi->target) {
>  		spi->target_abort = spi_geni_target_abort;
> +		mas->target_gpio = devm_gpiod_get_index_optional(dev, "ready", 0,
> +								 GPIOD_OUT_LOW);

Is there a reason for the get_index_ variant specifically?

i.e. why not just devm_gpiod_get_optional()?

Konrad