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>

drivers/mmc/core/sd.c

@@ -646,8 +646,13 @@ static int mmc_sd_init_uhs_card(struct mmc_card *card)
 	if (err)
 		goto out;
 
-	/* SPI mode doesn't define CMD19 */
-	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->sd_bus_speed == UHS_SDR50_BUS_SPEED ||
+			 card->sd_bus_speed == UHS_SDR104_BUS_SPEED)) {
 		mmc_host_clk_hold(card->host);
 		err = card->host->ops->execute_tuning(card->host,
 						      MMC_SEND_TUNING_BLOCK);

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: