[PATCH] spi: atmel: Fix PDC transfer setup bug

[Dan.Sneddon at microchip.com]

Hi Ville,

On 9/16/21 8:16 AM, Ville Baillie wrote:
> [Some people who received this message don't often get email from villeb at bytesnap.co.uk. Learn why this is important at http://aka.ms/LearnAboutSenderIdentification.]
> 
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
>  From 614bcf515cc8dbd1b7573a2fbf369fc84fca0501 Mon Sep 17 00:00:00 2001
> From: Ville Baillie <villeb at bytesnap.co.uk>
> Date: Thu, 16 Sep 2021 14:16:46 +0000
> Subject: [PATCH] spi: atmel: Fix PDC transfer setup bug
> 
> Commit d370f4b2808d ("spi: atmel: Switch to transfer_one transfer
> method") refactored the code and changed a conditional causing
> atmel_spi_dma_map_xfer to never be called in PDC mode. This causes the
> driver to silently fail.
> 
> This patch changes the conditional to match the behaviour of the
> previous commit before the refactor.
> 
> Signed-off-by: Ville Baillie <villeb at bytesnap.co.uk>
> ---
>   drivers/spi/spi-atmel.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
> index 788dcdf25f00..f00e9c9b426e 100644
> --- a/drivers/spi/spi-atmel.c
> +++ b/drivers/spi/spi-atmel.c
> @@ -1301,7 +1301,7 @@ static int atmel_spi_one_transfer(struct spi_master *master,
>           * DMA map early, for performance (empties dcache ASAP) and
>           * better fault reporting.
>           */
> -       if ((!master->cur_msg_mapped)
> +       if ((!master->cur_msg->is_dma_mapped)
>                  && as->use_pdc) {
>                  if (atmel_spi_dma_map_xfer(as, xfer) < 0)
>                          return -ENOMEM;
Looks like the same change should be made at the end of that same 
function where the call to atmel_spi_dma_unmap_xfer is made.
> --
> 2.17.1
>