Re: [PATCH v6 11/18] dmaengine: sh: rz-dmac: Drop the update of channel->chctrl with CHCTRL_SETEN

[Tommaso Merciai]

On Tue, May 26, 2026 at 11:47:03AM +0300, Claudiu Beznea wrote:
> From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
> 
> The CHCTRL_SETEN bit is explicitly set in rz_dmac_enable_hw(). Updating
> struct rz_dmac_chan::chctrl with this bit in
> rz_dmac_prepare_desc_for_memcpy() and rz_dmac_prepare_descs_for_slave_sg()
> is unnecessary in the current code base. Moreover, it conflicts with the
> configuration sequence that will be used for cyclic DMA channels during
> suspend to RAM. Cyclic DMA support will be introduced in subsequent
> commits.
> 
> This is a preparatory commit for cyclic DMA suspend to RAM support.
>

Tested-by: Tommaso Merciai <tommaso.merciai.xr@xxxxxxxxxxxxxx>

> Reviewed-by: Frank Li <Frank.Li@xxxxxxx>
> Tested-by: John Madieu <john.madieu.xa@xxxxxxxxxxxxxx>
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
> ---
> 
> Changes in v6:
> - collected tags
> 
> Changes in v5:
> - none
> 
> Changes in v4:
> - set channel->chctrl = 0 in rz_dmac_prepare_descs_for_slave_sg()
> 
> Changes in v3:
> - none
> 
> Changes in v2:
> - fixed typos in patch title and patch description
> 
>  drivers/dma/sh/rz-dmac.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c
> index 557364443a5f..c9c00650ddd5 100644
> --- a/drivers/dma/sh/rz-dmac.c
> +++ b/drivers/dma/sh/rz-dmac.c
> @@ -377,7 +377,7 @@ static void rz_dmac_prepare_desc_for_memcpy(struct rz_dmac_chan *channel)
>  	rz_dmac_set_dma_req_no(dmac, channel->index, dmac->info->default_dma_req_no);
>  
>  	channel->chcfg = chcfg;
> -	channel->chctrl = CHCTRL_STG | CHCTRL_SETEN;
> +	channel->chctrl = CHCTRL_STG;
>  }
>  
>  static void rz_dmac_prepare_descs_for_slave_sg(struct rz_dmac_chan *channel)
> @@ -428,7 +428,7 @@ static void rz_dmac_prepare_descs_for_slave_sg(struct rz_dmac_chan *channel)
>  
>  	rz_dmac_set_dma_req_no(dmac, channel->index, channel->mid_rid);
>  
> -	channel->chctrl = CHCTRL_SETEN;
> +	channel->chctrl = 0;
>  }
>  
>  static void rz_dmac_xfer_desc(struct rz_dmac_chan *chan)
> -- 
> 2.43.0
>