Am Sonntag, den 27.01.2019, 23:08 -0700 schrieb Angus Ainslie (Purism):
> On i.mx8mq, there are two sdma instances, and the common dma framework
> will get a channel dynamically from any available sdma instance whether
> it's the first sdma device or the second sdma device. Some IPs like
> SAI only work with sdma2 not sdma1. To make sure the sdma channel is from
> the correct sdma device, use the node pointer to match.
>
> Signed-off-by: Angus Ainslie (Purism) <angus@xxxxxxxx>
Reviewed-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> ---
> drivers/dma/imx-sdma.c | 6 ++++++
> include/linux/platform_data/dma-imx.h | 1 +
> 2 files changed, 7 insertions(+)
>
> diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
> index c4db4fe6bcc9..d5f86becf59e 100644
> --- a/drivers/dma/imx-sdma.c
> +++ b/drivers/dma/imx-sdma.c
> @@ -1918,11 +1918,16 @@ static int sdma_init(struct sdma_engine *sdma)
> static bool sdma_filter_fn(struct dma_chan *chan, void *fn_param)
> {
> struct sdma_channel *sdmac = to_sdma_chan(chan);
> + struct sdma_engine *sdma = sdmac->sdma;
> struct imx_dma_data *data = fn_param;
>
> if (!imx_dma_is_general_purpose(chan))
> return false;
>
> + /* return false if it's not the right device */
> + if (sdma->dev->of_node != data->of_node)
> + return false;
> +
> sdmac->data = *data;
> chan->private = &sdmac->data;
>
> @@ -1950,6 +1955,7 @@ static struct dma_chan *sdma_xlate(struct of_phandle_args *dma_spec,
> * be set to sdmac->event_id1.
> */
> data.dma_request2 = 0;
> + data.of_node = ofdma->of_node;
>
> return dma_request_channel(mask, sdma_filter_fn, &data);
> }
> diff --git a/include/linux/platform_data/dma-imx.h b/include/linux/platform_data/dma-imx.h
> index 7d964e787299..9daea8d42a10 100644
> --- a/include/linux/platform_data/dma-imx.h
> +++ b/include/linux/platform_data/dma-imx.h
> @@ -55,6 +55,7 @@ struct imx_dma_data {
> int dma_request2; /* secondary DMA request line */
> enum sdma_peripheral_type peripheral_type;
> int priority;
> + struct device_node *of_node;
> };
>
> static inline int imx_dma_is_ipu(struct dma_chan *chan)
