Re: [PATCH v2 3/4] dmaengine: rcar-dmac: Add helpers for clearing DMA channel status

From: Laurent Pinchart
Date: Tue Jan 26 2021 - 22:38:52 EST


Hi Geert,

Thank you for the patch.

On Mon, Jan 25, 2021 at 03:24:30PM +0100, Geert Uytterhoeven wrote:
> Extract the code to clear the status of one or all channels into their
> own helpers, to prepare for the different handling of the R-Car V3U SoC.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>

> ---
> v2:
> - No changes.
> ---
> drivers/dma/sh/rcar-dmac.c | 15 +++++++++++++--
> 1 file changed, 13 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c
> index 537550b4121bbc22..7a0f802c61e5152d 100644
> --- a/drivers/dma/sh/rcar-dmac.c
> +++ b/drivers/dma/sh/rcar-dmac.c
> @@ -336,6 +336,17 @@ static void rcar_dmac_chan_write(struct rcar_dmac_chan *chan, u32 reg, u32 data)
> writel(data, chan->iomem + reg);
> }
>
> +static void rcar_dmac_chan_clear(struct rcar_dmac *dmac,
> + struct rcar_dmac_chan *chan)
> +{
> + rcar_dmac_write(dmac, RCAR_DMACHCLR, BIT(chan->index));
> +}
> +
> +static void rcar_dmac_chan_clear_all(struct rcar_dmac *dmac)
> +{
> + rcar_dmac_write(dmac, RCAR_DMACHCLR, dmac->channels_mask);
> +}
> +
> /* -----------------------------------------------------------------------------
> * Initialization and configuration
> */
> @@ -451,7 +462,7 @@ static int rcar_dmac_init(struct rcar_dmac *dmac)
> u16 dmaor;
>
> /* Clear all channels and enable the DMAC globally. */
> - rcar_dmac_write(dmac, RCAR_DMACHCLR, dmac->channels_mask);
> + rcar_dmac_chan_clear_all(dmac);
> rcar_dmac_write(dmac, RCAR_DMAOR,
> RCAR_DMAOR_PRI_FIXED | RCAR_DMAOR_DME);
>
> @@ -1566,7 +1577,7 @@ static irqreturn_t rcar_dmac_isr_channel(int irq, void *dev)
> * because channel is already stopped in error case.
> * We need to clear register and check DE bit as recovery.
> */
> - rcar_dmac_write(dmac, RCAR_DMACHCLR, 1 << chan->index);
> + rcar_dmac_chan_clear(dmac, chan);
> rcar_dmac_chcr_de_barrier(chan);
> reinit = true;
> goto spin_lock_end;

--
Regards,

Laurent Pinchart