diff mbox

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

Message ID 1443960253-4082-1-git-send-email-21cnbao@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Barry Song Oct. 4, 2015, 12:04 p.m. UTC
From: Weijun Yang <york.yang@csr.com>

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>
---
 drivers/mmc/core/sd.c | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

Comments

Ulf Hansson Oct. 5, 2015, 10:56 a.m. UTC | #1
On 4 October 2015 at 14:04, Barry Song <21cnbao@gmail.com> wrote:
> From: Weijun Yang <york.yang@csr.com>
>
> 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
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

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.
+		 */
+		if (err && (card->sd_bus_speed == UHS_DDR50_BUS_SPEED)) {
+			pr_warn("%s: ddr50 tuning failed\n", mmc_hostname(card->host));
+			err = 0;
+		}
+	}
+
 out:
 	kfree(status);