Re: [PATCH v3 1/3] mmc: core: enable CMD19 tuning for DDR50 mode

Ulf Hansson
2015-10-05T10:56:43Z

> As SD Specifications Part1 Physical Layer Specification Version
> 3.01 says, CMD19 tuning is available for unlocked cards in transfer
> state of 1.8V signaling mode. The small difference between v3.00
> and 3.01 spec means that CMD19 tuning is also available for DDR50
> mode.
>
> Signed-off-by: Weijun Yang <york.yang@csr.com>
> Signed-off-by: Barry Song <Baohua.Song@csr.com>

Thanks, applied for next - although with some minor changes as described below.

> ---
> drivers/mmc/core/sd.c | 19 +++++++++++++++++--
> 1 file changed, 17 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
> index 4e7366a..eaf8cb3 100644
> --- a/drivers/mmc/core/sd.c
> +++ b/drivers/mmc/core/sd.c
> @@ -628,9 +628,24 @@ static int mmc_sd_init_uhs_card(struct mmc_card *card)
> * SDR104 mode SD-cards. Note that tuning is mandatory for SDR104.
> */
> if (!mmc_host_is_spi(card->host) &&
> - (card->sd_bus_speed == UHS_SDR50_BUS_SPEED ||
> - card->sd_bus_speed == UHS_SDR104_BUS_SPEED))
> + (card->sd_bus_speed == UHS_SDR50_BUS_SPEED ||
> + card->sd_bus_speed == UHS_DDR50_BUS_SPEED ||
> + card->sd_bus_speed == UHS_SDR104_BUS_SPEED)) {
> err = mmc_execute_tuning(card);
> +
> + /*
> + * As SD Specifications Part1 Physical Layer Specification Version
> + * 3.01 says, CMD19 tuning is available for unlocked cards in transfer
> + * state of 1.8V signaling mode. The small difference between v3.00
> + * and 3.01 spec means that CMD19 tuning is also available for DDR50
> + * mode.
> + */

Checkpatch warned about long lines, so I changed them.

> + if (err && (card->sd_bus_speed == UHS_DDR50_BUS_SPEED)) {

Removed a pair of unnecessary parentheses for this if statement.

> + pr_warn("%s: ddr50 tuning failed\n", mmc_hostname(card->host));
> + err = 0;
> + }
> + }
> +
> out:
> kfree(status);
>
> --
> 1.9.1
>

Kind regards
Uffe