On Tue, Dec 17, 2019 at 11:41 AM Peter Ujfalusi <peter.ujfalusi@xxxxxx> wrote:
> dma_request_slave_channel() is a wrapper on top of dma_request_chan()
> eating up the error code.
>
> By using dma_request_chan() directly the driver can support deferred
> probing against DMA.
>
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
One comment below.
> --- a/drivers/media/platform/rcar_drif.c
> +++ b/drivers/media/platform/rcar_drif.c
> @@ -275,10 +275,10 @@ static int rcar_drif_alloc_dmachannels(struct rcar_drif_sdr *sdr)
> for_each_rcar_drif_channel(i, &sdr->cur_ch_mask) {
> struct rcar_drif *ch = sdr->ch[i];
>
> - ch->dmach = dma_request_slave_channel(&ch->pdev->dev, "rx");
> - if (!ch->dmach) {
> + ch->dmach = dma_request_chan(&ch->pdev->dev, "rx");
> + if (IS_ERR(ch->dmach)) {
> rdrif_err(sdr, "ch%u: dma channel req failed\n", i);
Now there is an error code, you might (1) want to print it, and (2) only
do so when it is not due to probe deferral:
if (PTR_ERR(ch->dmach) != -EPROBE_DEFER)
rdrif_err(sdr, "ch%u: dma channel req failed %pe\n",
i, ch->dmach);
> - ret = -ENODEV;
> + ret = PTR_ERR(ch->dmach);
> goto dmach_error;
> }
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
