Re: [PATCH 2/2] dmaengine: at_hdmac: Remove unused field values that do not fit

From: Tudor Ambarus
Date: Tue May 23 2023 - 10:04:23 EST


Hi, Peter,

On 5/23/23 13:42, Peter Rosin wrote:
> The values are not used, and they do not fit in the intended
> register field (ATC_FC, 2 bits wide). Kill 'em all.
>
Actually ATC_FC should be set to GENMASK(23, 21) and keep the other
definitions, see:
http://ww1.microchip.com/downloads/en/devicedoc/Atmel-6438-32-bit-ARM926-Embedded-Microprocessor-SAM9G45_Datasheet.pdf

After you update the patch you should also add:
Fixes: d8840a7edcf0 ("dmaengine: at_hdmac: Use bitfield access macros")
Cc: stable@xxxxxxxxxxxxxxx
so that it gets backported to Linux-stable.

Feel free to add my R-b tag after addressing the comments:
Reviewed-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxx>

> Signed-off-by: Peter Rosin <peda@xxxxxxxxxx>
> ---
> drivers/dma/at_hdmac.c | 4 ----
> 1 file changed, 4 deletions(-)
>
> diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
> index 6f352160bc3b..51d0a0c7aaf7 100644
> --- a/drivers/dma/at_hdmac.c
> +++ b/drivers/dma/at_hdmac.c
> @@ -137,10 +137,6 @@
> #define ATC_FC_MEM2PER 0x1 /* Mem-to-Periph (DMA) */
> #define ATC_FC_PER2MEM 0x2 /* Periph-to-Mem (DMA) */
> #define ATC_FC_PER2PER 0x3 /* Periph-to-Periph (DMA) */
> -#define ATC_FC_PER2MEM_PER 0x4 /* Periph-to-Mem (Peripheral) */
> -#define ATC_FC_MEM2PER_PER 0x5 /* Mem-to-Periph (Peripheral) */
> -#define ATC_FC_PER2PER_SRCPER 0x6 /* Periph-to-Periph (Src Peripheral) */
> -#define ATC_FC_PER2PER_DSTPER 0x7 /* Periph-to-Periph (Dst Peripheral) */
> #define ATC_SRC_ADDR_MODE GENMASK(25, 24)
> #define ATC_SRC_ADDR_MODE_INCR 0x0 /* Incrementing Mode */
> #define ATC_SRC_ADDR_MODE_DECR 0x1 /* Decrementing Mode */