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From:   Manish Narani <manish.narani@xilinx.com>
To:     <michal.simek@xilinx.com>, <adrian.hunter@intel.com>,
        <ulf.hansson@linaro.org>
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        <linux-mmc@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <git@xilinx.com>, Manish Narani <manish.narani@xilinx.com>,
        Sai Krishna Potthuri <lakshmi.sai.krishna.potthuri@xilinx.com>
Subject: [PATCH] mmc: sdhci-of-arasan: Allow configuring zero tap values
Date:   Tue, 10 Nov 2020 23:12:02 +0530
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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.

Signed-off-by: Sai Krishna Potthuri <lakshmi.sai.krishna.potthuri@xilinx.com>
Signed-off-by: Manish Narani <manish.narani@xilinx.com>
---
 drivers/mmc/host/sdhci-of-arasan.c | 40 ++++++------------------------
 1 file changed, 8 insertions(+), 32 deletions(-)

diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index 829ccef87426..100621e55427 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/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) {
-- 
2.17.1