[v5 3/4] mmc: sdhci-cadence: Update PHY delay configuration

[Piotr Sroka]

DTS properties are used instead of fixed data
because PHY settings can be different for different chips/boards.

Signed-off-by: Piotr Sroka <piotrs@xxxxxxxxxxx>
---
Changes for v2:
- dts part was removed from this patch
- most delays were moved from dts file
  to data associated with an SoC specific compatible
- remove unrelated changes
---
Changes for v3:
- move all delays back to dts because they are also boards dependent
- prefix all of the Cadence-specific properties with cdns prefix
- put checking delay properties inside the for loop
  instead of using a lot of single if expressions
---
Changes for v4:
- remove unecessary declaration of sdhci_cdns_match
- format fix (blank line removed)
---
Changes for v5:
- use driver version from next branch, with applied enhanced strobe feature support.
- change name of property to be consistent with timing modes 
  available in Linux
---
 drivers/mmc/host/sdhci-cadence.c | 53 ++++++++++++++++++++++++++++++++++------
 1 file changed, 46 insertions(+), 7 deletions(-)

diff --git a/drivers/mmc/host/sdhci-cadence.c b/drivers/mmc/host/sdhci-cadence.c
index 83c3b55..c3c7090 100644
--- a/drivers/mmc/host/sdhci-cadence.c
+++ b/drivers/mmc/host/sdhci-cadence.c
@@ -18,6 +18,7 @@
 #include <linux/module.h>
 #include <linux/mmc/host.h>
 #include <linux/mmc/mmc.h>
+#include <linux/of.h>
 
 #include "sdhci-pltfm.h"
 
@@ -55,6 +56,9 @@
 #define SDHCI_CDNS_PHY_DLY_EMMC_LEGACY	0x06
 #define SDHCI_CDNS_PHY_DLY_EMMC_SDR	0x07
 #define SDHCI_CDNS_PHY_DLY_EMMC_DDR	0x08
+#define SDHCI_CDNS_PHY_DLY_SDCLK	0x0b
+#define SDHCI_CDNS_PHY_DLY_HSMMC	0x0c
+#define SDHCI_CDNS_PHY_DLY_STROBE	0x0d
 
 /*
  * The tuned val register is 6 bit-wide, but not the whole of the range is
@@ -68,6 +72,25 @@ struct sdhci_cdns_priv {
 	bool enhanced_strobe;
 };
 
+struct sdhci_cdns_phy_cfg {
+	const char *property;
+	u8 addr;
+};
+
+static const struct sdhci_cdns_phy_cfg sdhci_cdns_phy_cfgs[] = {
+	{ "cdns,phy-input-delay-sd-highspeed", SDHCI_CDNS_PHY_DLY_SD_HS, },
+	{ "cdns,phy-input-delay-legacy", SDHCI_CDNS_PHY_DLY_SD_DEFAULT, },
+	{ "cdns,phy-input-delay-sd-uhs-sdr12", SDHCI_CDNS_PHY_DLY_UHS_SDR12, },
+	{ "cdns,phy-input-delay-sd-uhs-sdr25", SDHCI_CDNS_PHY_DLY_UHS_SDR25, },
+	{ "cdns,phy-input-delay-sd-uhs-sdr50", SDHCI_CDNS_PHY_DLY_UHS_SDR50, },
+	{ "cdns,phy-input-delay-sd-uhs-ddr50", SDHCI_CDNS_PHY_DLY_UHS_DDR50, },
+	{ "cdns,phy-input-delay-mmc-highspeed", SDHCI_CDNS_PHY_DLY_EMMC_SDR, },
+	{ "cdns,phy-input-delay-mmc-ddr", SDHCI_CDNS_PHY_DLY_EMMC_DDR, },
+	{ "cdns,phy-dll-delay-sdclk", SDHCI_CDNS_PHY_DLY_SDCLK, },
+	{ "cdns,phy-dll-delay-sdclk-hsmmc", SDHCI_CDNS_PHY_DLY_HSMMC, },
+	{ "cdns,phy-dll-delay-strobe", SDHCI_CDNS_PHY_DLY_STROBE, },
+};
+
 static int sdhci_cdns_write_phy_reg(struct sdhci_cdns_priv *priv,
 				    u8 addr, u8 data)
 {
@@ -92,13 +115,26 @@ static int sdhci_cdns_write_phy_reg(struct sdhci_cdns_priv *priv,
 	return 0;
 }
 
-static void sdhci_cdns_phy_init(struct sdhci_cdns_priv *priv)
+static int sdhci_cdns_phy_init(struct device_node *np,
+			       struct sdhci_cdns_priv *priv)
 {
-	sdhci_cdns_write_phy_reg(priv, SDHCI_CDNS_PHY_DLY_SD_HS, 4);
-	sdhci_cdns_write_phy_reg(priv, SDHCI_CDNS_PHY_DLY_SD_DEFAULT, 4);
-	sdhci_cdns_write_phy_reg(priv, SDHCI_CDNS_PHY_DLY_EMMC_LEGACY, 9);
-	sdhci_cdns_write_phy_reg(priv, SDHCI_CDNS_PHY_DLY_EMMC_SDR, 2);
-	sdhci_cdns_write_phy_reg(priv, SDHCI_CDNS_PHY_DLY_EMMC_DDR, 3);
+	u32 val;
+	int ret, i;
+
+	for (i = 0; i < ARRAY_SIZE(sdhci_cdns_phy_cfgs); i++) {
+		ret = of_property_read_u32(np, sdhci_cdns_phy_cfgs[i].property,
+					   &val);
+		if (ret)
+			continue;
+
+		ret = sdhci_cdns_write_phy_reg(priv,
+					       sdhci_cdns_phy_cfgs[i].addr,
+					       val);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
 }
 
 static inline void *sdhci_cdns_priv(struct sdhci_host *host)
@@ -267,6 +303,7 @@ static int sdhci_cdns_probe(struct platform_device *pdev)
 	struct sdhci_cdns_priv *priv;
 	struct clk *clk;
 	int ret;
+	struct device *dev = &pdev->dev;
 
 	clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(clk))
@@ -297,7 +334,9 @@ static int sdhci_cdns_probe(struct platform_device *pdev)
 	if (ret)
 		goto free;
 
-	sdhci_cdns_phy_init(priv);
+	ret = sdhci_cdns_phy_init(dev->of_node, priv);
+	if (ret)
+		goto free;
 
 	ret = sdhci_add_host(host);
 	if (ret)
-- 
2.2.2