mmc: core: Only execute tuning for SDR50 and SDR104

Only execute tuning for sd and sdio devices that are using
SDR50 or SDR104.

Make sure clock is hold during tuning for sdio devices.

Signed-off-by: Fredrik Soderstedt <fredrik.soderstedt@stericsson.com>
Acked-by: Johan Rudholm <jrudholm@gmail.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
(cherry picked from commit 810e08ee425f8d7327e4b30069a9b2b3dccfc67d)

1 files changed, 10 insertions, 2 deletions

diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index 6889a821c1da..444668c210b2 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -563,10 +563,18 @@ static int mmc_sdio_init_uhs_card(struct mmc_card *card)
         if (err)
                 goto out;
 
-        /* Initialize and start re-tuning timer */
-        if (!mmc_host_is_spi(card->host) && card->host->ops->execute_tuning)
+        /*
+         * SPI mode doesn't define CMD19 and tuning is only valid for SDR50 and
+         * SDR104 mode SD-cards. Note that tuning is mandatory for SDR104.
+         */
+        if (!mmc_host_is_spi(card->host) && card->host->ops->execute_tuning &&
+                        ((card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR50) ||
+                         (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR104))) {
+                mmc_host_clk_hold(card->host);
                 err = card->host->ops->execute_tuning(card->host,
                                                       MMC_SEND_TUNING_BLOCK);
+                mmc_host_clk_release(card->host);
+        }
 
 out: