Re: [PATCH 2/4] MMC: omap_hsmmc: fix DMA config block

Porter, Matt
2012-10-12T11:07:12Z

On Oct 12, 2012, at 6:58 AM, Daniel Mack wrote:

> The .direction field of the config passed to dmaengine_slave_config()
> must be set in order to make the generic code store the configured bus
> width.
>
> Without this patch, I keep getting the following error on a AM33xx
> board:
>
> [ 1.963144] edma-dma-engine edma-dma-engine.0: Undefined slave buswidth
> [ 1.970158] omap_hsmmc mmc.4: prep_slave_sg() failed
> [ 1.975454] mmc1: error -1 whilst initialising SD card

Hi Daniel,

I posted a patch to fix the slave config handling in the EDMA DMA Engine
driver here: https://patchwork.kernel.org/patch/1474411/

Vinod didn't pick that up for 3.7, probably because it's not triggered by
any of the in-tree davinci drivers that are converted. However, I am
carrying the same patch in the am335x edma dmaengine v2 series
(https://lkml.org/lkml/2012/10/11/345) so there's no need to change this
driver.

-Matt

>
> Signed-off-by: Daniel Mack <zonque@gmail.com>
> Cc: Venkatraman S <svenkatr@ti.com>
> Cc: Chris Ball <cjb@laptop.org>
> Cc: Grant Likely <grant.likely@secretlab.ca>
> Cc: Rob Herring <rob.herring@calxeda.com>
> Cc: linux-omap@vger.kernel.org
> Cc: Matt Porter <mporter@ti.com>
> Cc: Russell King <rmk+kernel@arm.linux.org.uk>
> ---
> drivers/mmc/host/omap_hsmmc.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
> index 4b70823..2c57b0d 100644
> --- a/drivers/mmc/host/omap_hsmmc.c
> +++ b/drivers/mmc/host/omap_hsmmc.c
> @@ -1260,6 +1260,8 @@ static int omap_hsmmc_start_dma_transfer(struct omap_hsmmc_host *host,
> cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
> cfg.src_maxburst = data->blksz / 4;
> cfg.dst_maxburst = data->blksz / 4;
> + cfg.direction = data->flags & MMC_DATA_WRITE ?
> + DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
>
> ret = dmaengine_slave_config(chan, &cfg);
> if (ret)
> @@ -1270,8 +1272,8 @@ static int omap_hsmmc_start_dma_transfer(struct omap_hsmmc_host *host,
> return ret;
>
> tx = dmaengine_prep_slave_sg(chan, data->sg, data->sg_len,
> - data->flags & MMC_DATA_WRITE ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
> - DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
> + cfg.direction,
> + DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
> if (!tx) {
> dev_err(mmc_dev(host->mmc), "prep_slave_sg() failed\n");
> /* FIXME: cleanup */
> --
> 1.7.11.4
>