Hi Zong,
On Wed, Jan 5, 2022 at 6:44 AM Zong Li <zong.li@xxxxxxxxxx> wrote:
> It currently assumes that there are four channels by default, it might
> cause the error if there is actually less than four channels. Change
> that by getting number of channel from device tree.
>
> Signed-off-by: Zong Li <zong.li@xxxxxxxxxx>
Thanks for your patch!
> --- a/drivers/dma/sf-pdma/sf-pdma.c
> +++ b/drivers/dma/sf-pdma/sf-pdma.c
> @@ -484,21 +484,24 @@ static int sf_pdma_probe(struct platform_device *pdev)
> struct sf_pdma *pdma;
> struct sf_pdma_chan *chan;
> struct resource *res;
> - int len, chans;
> - int ret;
> + int len, ret;
> const enum dma_slave_buswidth widths =
> DMA_SLAVE_BUSWIDTH_1_BYTE | DMA_SLAVE_BUSWIDTH_2_BYTES |
> DMA_SLAVE_BUSWIDTH_4_BYTES | DMA_SLAVE_BUSWIDTH_8_BYTES |
> DMA_SLAVE_BUSWIDTH_16_BYTES | DMA_SLAVE_BUSWIDTH_32_BYTES |
> DMA_SLAVE_BUSWIDTH_64_BYTES;
>
> - chans = PDMA_NR_CH;
> - len = sizeof(*pdma) + sizeof(*chan) * chans;
> + len = sizeof(*pdma) + sizeof(*chan) * PDMA_MAX_NR_CH;
> pdma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL);
> if (!pdma)
> return -ENOMEM;
>
> - pdma->n_chans = chans;
> + ret = of_property_read_u32(pdev->dev.of_node, "dma-channels",
> + &pdma->n_chans);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to read dma-channels\n");
> + return ret;
Note that this is not backwards-compatible with existing DTBs, which
lack the "dma-channels" property.
Perhaps you want to fallback to a default of 4 instead?
> + }
>
> res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> pdma->membase = devm_ioremap_resource(&pdev->dev, res);
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
