Re: [PATCH] spi: tegra114: Don't fail set_cs_timing when delays are zero

[Jon Hunter <jonathanh@nvidia.com>]

On 24/04/2025 03:03, Aaron Kling via B4 Relay wrote:
> From: Aaron Kling <webgeek1234@gmail.com>
> 
> The original code would skip null delay pointers, but when the pointers
> were converted to point within the spi_device struct, the check was not
> updated to skip delays of zero. Hence all spi devices that didn't set
> delays would fail to probe.
> 
> Fixes: 04e6bb0d6bb1 ("spi: modify set_cs_timing parameter")
> Cc: stable@vger.kernel.org
> Signed-off-by: Aaron Kling <webgeek1234@gmail.com>
> ---
>   drivers/spi/spi-tegra114.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/spi/spi-tegra114.c b/drivers/spi/spi-tegra114.c
> index 3822d7c8d8edb9730e937df50d1c75e095dd18ec..2a8bb798e95b954fe573f1c50445ed2e7fcbfd78 100644
> --- a/drivers/spi/spi-tegra114.c
> +++ b/drivers/spi/spi-tegra114.c
> @@ -728,9 +728,9 @@ static int tegra_spi_set_hw_cs_timing(struct spi_device *spi)
>   	u32 inactive_cycles;
>   	u8 cs_state;
>   
> -	if (setup->unit != SPI_DELAY_UNIT_SCK ||
> -	    hold->unit != SPI_DELAY_UNIT_SCK ||
> -	    inactive->unit != SPI_DELAY_UNIT_SCK) {
> +	if ((setup->unit && setup->unit != SPI_DELAY_UNIT_SCK) ||
> +	    (hold->unit && hold->unit != SPI_DELAY_UNIT_SCK) ||
> +	    (inactive->unit && inactive->unit != SPI_DELAY_UNIT_SCK)) {

The above does not look correct to me. For example, if 'setup->unit' is 
0, this means that the unit is 'SPI_DELAY_UNIT_USECS' and does not 
indicate that the delay is 0.

Shouldn't the above be ...

  if ((setup && setup->unit != SPI_DELAY_UNIT_SCK) ||
      (hold && hold->unit != SPI_DELAY_UNIT_SCK) ||
      (inactive && inactive->unit != SPI_DELAY_UNIT_SCK)) {

Jon

-- 
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