mmc: sdhci-of-arasan: Allow configuring zero tap values

Allow configuring the Output and Input tap values with zero to avoid
failures in some cases (one of them is SD boot mode) where the output
and input tap values may be already set to non-zero.

Fixes: a5c8b2a ("mmc: sdhci-of-arasan: Add support for ZynqMP Platform Tap Delays Setup")
Signed-off-by: Sai Krishna Potthuri <lakshmi.sai.krishna.potthuri@xilinx.com>
Signed-off-by: Manish Narani <manish.narani@xilinx.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/1605515565-117562-2-git-send-email-manish.narani@xilinx.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Author: mnarani

drivers/mmc/host/sdhci-of-arasan.c

@@ -600,14 +600,8 @@ static int sdhci_zynqmp_sdcardclk_set_phase(struct clk_hw *hw, int degrees)
 	u8 tap_delay, tap_max = 0;
 	int ret;
 
-	/*
-	 * This is applicable for SDHCI_SPEC_300 and above
-	 * ZynqMP does not set phase for <=25MHz clock.
-	 * If degrees is zero, no need to do anything.
-	 */
-	if (host->version < SDHCI_SPEC_300 ||
-	    host->timing == MMC_TIMING_LEGACY ||
-	    host->timing == MMC_TIMING_UHS_SDR12 || !degrees)
+	/* This is applicable for SDHCI_SPEC_300 and above */
+	if (host->version < SDHCI_SPEC_300)
 		return 0;
 
 	switch (host->timing) {
@@ -668,14 +662,8 @@ static int sdhci_zynqmp_sampleclk_set_phase(struct clk_hw *hw, int degrees)
 	u8 tap_delay, tap_max = 0;
 	int ret;
 
-	/*
-	 * This is applicable for SDHCI_SPEC_300 and above
-	 * ZynqMP does not set phase for <=25MHz clock.
-	 * If degrees is zero, no need to do anything.
-	 */
-	if (host->version < SDHCI_SPEC_300 ||
-	    host->timing == MMC_TIMING_LEGACY ||
-	    host->timing == MMC_TIMING_UHS_SDR12 || !degrees)
+	/* This is applicable for SDHCI_SPEC_300 and above */
+	if (host->version < SDHCI_SPEC_300)
 		return 0;
 
 	switch (host->timing) {
@@ -733,14 +721,8 @@ static int sdhci_versal_sdcardclk_set_phase(struct clk_hw *hw, int degrees)
 	struct sdhci_host *host = sdhci_arasan->host;
 	u8 tap_delay, tap_max = 0;
 
-	/*
-	 * This is applicable for SDHCI_SPEC_300 and above
-	 * Versal does not set phase for <=25MHz clock.
-	 * If degrees is zero, no need to do anything.
-	 */
-	if (host->version < SDHCI_SPEC_300 ||
-	    host->timing == MMC_TIMING_LEGACY ||
-	    host->timing == MMC_TIMING_UHS_SDR12 || !degrees)
+	/* This is applicable for SDHCI_SPEC_300 and above */
+	if (host->version < SDHCI_SPEC_300)
 		return 0;
 
 	switch (host->timing) {
@@ -804,14 +786,8 @@ static int sdhci_versal_sampleclk_set_phase(struct clk_hw *hw, int degrees)
 	struct sdhci_host *host = sdhci_arasan->host;
 	u8 tap_delay, tap_max = 0;
 
-	/*
-	 * This is applicable for SDHCI_SPEC_300 and above
-	 * Versal does not set phase for <=25MHz clock.
-	 * If degrees is zero, no need to do anything.
-	 */
-	if (host->version < SDHCI_SPEC_300 ||
-	    host->timing == MMC_TIMING_LEGACY ||
-	    host->timing == MMC_TIMING_UHS_SDR12 || !degrees)
+	/* This is applicable for SDHCI_SPEC_300 and above */
+	if (host->version < SDHCI_SPEC_300)
 		return 0;
 
 	switch (host->timing) {