On 23 May 2017 at 12:11, Phil Elwell <phil@xxxxxxxxxxxxxxx> wrote: > On 23/05/2017 08:58, Ulf Hansson wrote: >> On 22 May 2017 at 11:09, Phil Elwell <phil@xxxxxxxxxxxxxxx> wrote: >>> since: >>> commit 0589342c27944e50ebd7a54f5215002b6598b748 >>> Author: Rob Herring <rob.herring@xxxxxxxxxxx> >>> Date: Tue Oct 29 23:36:46 2013 -0500 >>> >>> of: set dma_mask to point to coherent_dma_mask >>> >>> Platform devices created by DT code don't initialize dma_mask pointer to >>> anything. Set it to coherent_dma_mask by default if the architecture >>> code has not set it. >>> >>> the mmc-spi driver no longer detects the sd-cards any longer. >>> >>> This patch disables the offending section in mmc_spi >>> so that the driver works again and detects the sd card normally. >>> >>> There is no real negative impact as the spi-framework >>> does no longer rely on driver-provided DMA mappings but >>> maps the transfers transparently. >>> >>> Signed-off-by: Martin Sperl <kernel@xxxxxxxxxxxxxxxx> >>> Submitted-by: Phil Elwell <phil@xxxxxxxxxxxxxxx> >>> --- >>> drivers/mmc/host/mmc_spi.c | 11 +++++++++++ >>> 1 file changed, 11 insertions(+) >>> >>> diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c >>> index ae19d83bb9de0..16946e2513afa 100644 >>> --- a/drivers/mmc/host/mmc_spi.c >>> +++ b/drivers/mmc/host/mmc_spi.c >>> @@ -1387,6 +1387,16 @@ static int mmc_spi_probe(struct spi_device *spi) >>> if (!host->data) >>> goto fail_nobuf1; >>> >>> + /* for some reason mmc_spi does not work with this enabled >>> + * it is not needed anyway, as the SPI framework does DMA >>> + * transfers now automatically >>> + * the patch that introduced this was: >>> + * commit 0589342c27944e50ebd7a54f5215002b6598b748 >>> + * Author: Rob Herring <rob.herring@xxxxxxxxxxx> >>> + * Date: Tue Oct 29 23:36:46 2013 -0500 >>> + * of: set dma_mask to point to coherent_dma_mask >>> + */ >>> +#if 0 >>> if (spi->master->dev.parent->dma_mask) { >>> struct device *dev = spi->master->dev.parent; >>> >>> @@ -1402,6 +1412,7 @@ static int mmc_spi_probe(struct spi_device *spi) >>> host->data_dma, sizeof(*host->data), >>> DMA_BIDIRECTIONAL); >>> } >>> +#endif >>> >>> /* setup message for status/busy readback */ >>> spi_message_init(&host->readback); >> >> Phil, I am not sure how to go with this. >> >> Your change drops the dma implementation in the mmc_spi driver as >> host->dma_dev now never gets assigned. I do think that makes sense as >> the dma support should be implemented in the spi master driver and not >> in the spi client driver, which currently is the case for mmc_spi. >> >> Then perhaps a more proper change would be to remove the dma >> implementation in mmc_spi altogether? > > I don't have enough in-depth SPI knowledge to make that decision - I'm happy to go > with what the SPI experts recommend. Okay. Let's see. > >> And one more thing, next time also cc the spi-list and Mark Brown, to >> try to some broader input. > > Thanks for the tip, Ulf - I just went with what scripts/get_maintainer.pl suggested. > Perhaps that list needs to be updated? No, this is more a special case I would say. Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html