mmc: sdhci-xenon: ignore timing DDR52 in tuning

Emmc DDR52 mode uses fixed delay, return earlier if
timing is MMC_TIMING_MMC_DDR52 in execute tuning function.
Signed-off-by: Zhoujie Wu <zjwu@marvell.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/sdhci-xenon.c

@@ -311,7 +311,8 @@ static int xenon_execute_tuning(struct mmc_host *mmc, u32 opcode)
 {
 	struct sdhci_host *host = mmc_priv(mmc);
 
-	if (host->timing == MMC_TIMING_UHS_DDR50)
+	if (host->timing == MMC_TIMING_UHS_DDR50 ||
+		host->timing == MMC_TIMING_MMC_DDR52)
 		return 0;
 
 	/*