Re: [PATCH v1 1/1] mmc: block: fix the data timeout issue with ACMD22

["S, Venkatraman" <svenkatr@ti.com>]

On Wed, Jun 13, 2012 at 5:10 PM, Subhash Jadavani
<subhashj@codeaurora.org> wrote:
> If multi block write operation fails for SD card, during
> error handling we send the SD_APP_SEND_NUM_WR_BLKS (ACMD22)
> to know how many blocks were already programmed by card.
>
> But mmc_sd_num_wr_blocks() function which sends the ACMD22
> calculates the data timeout value from csd.tacc_ns and
> csd.tacc_clks parameters which will be 0 for block addressed
> (>2GB cards) SD card. This would result in timeout_ns and
> timeout_clks being 0 in the mmc_request passed to host driver.
> This means host controller would program its data timeout timer
> value with 0 which could result in DATA TIMEOUT errors from
> controller.
>
> To fix this issue, mmc_sd_num_wr_blocks() should instead
> just call the mmc_set_data_timeout() to calculate the
> data timeout value. mmc_set_data_timeout() function
> ensures that non zero timeout value is set even for
> block addressed SD cards.
>
> Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>

The patch log could be improvised (Just mention that
set_data_timeout() is reused .. etc")
Even otherwise, its fine.
Reviewed-by: Venkatraman S <svenkatr@ti.com>

> ---
>  drivers/mmc/card/block.c |   14 +-------------
>  1 files changed, 1 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
> index 7e3f453..f1c84de 100644
> --- a/drivers/mmc/card/block.c
> +++ b/drivers/mmc/card/block.c
> @@ -554,7 +554,6 @@ static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
>        struct mmc_request mrq = {NULL};
>        struct mmc_command cmd = {0};
>        struct mmc_data data = {0};
> -       unsigned int timeout_us;
>
>        struct scatterlist sg;
>
> @@ -574,23 +573,12 @@ static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
>        cmd.arg = 0;
>        cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
>
> -       data.timeout_ns = card->csd.tacc_ns * 100;
> -       data.timeout_clks = card->csd.tacc_clks * 100;
> -
> -       timeout_us = data.timeout_ns / 1000;
> -       timeout_us += data.timeout_clks * 1000 /
> -               (card->host->ios.clock / 1000);
> -
> -       if (timeout_us > 100000) {
> -               data.timeout_ns = 100000000;
> -               data.timeout_clks = 0;
> -       }
> -
>        data.blksz = 4;
>        data.blocks = 1;
>        data.flags = MMC_DATA_READ;
>        data.sg = &sg;
>        data.sg_len = 1;
> +       mmc_set_data_timeout(&data, card);
>
>        mrq.cmd = &cmd;
>        mrq.data = &data;
> --