[PATCH 7/7] ARM: dts: qcom: msm8974-klte: Add support for SD card

[Iskren Chernev]

The Samsung Galaxy S5 (klte), has 3 SDHCI nodes used for internal
storage, WiFi, external SD card slot. The external SD card slot is
similar to the internal storage.

The device has support for CD (card detect), but if enabled, the card is
not initialized properly if present during startup. That is why CD is
disabled and polling is used instead. Related thread [1]

[1] https://lore.kernel.org/linux-mmc/491cfef4-4a97-b6e8-0f41-d44e1c73eea4@xxxxxxxxx/

Signed-off-by: Iskren Chernev <iskren.chernev@xxxxxxxxx>
---
 .../boot/dts/qcom-msm8974-samsung-klte.dts    | 44 ++++++++++++++++++-
 1 file changed, 43 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/qcom-msm8974-samsung-klte.dts b/arch/arm/boot/dts/qcom-msm8974-samsung-klte.dts
index 989447beb4319..b0899107f3ced 100644
--- a/arch/arm/boot/dts/qcom-msm8974-samsung-klte.dts
+++ b/arch/arm/boot/dts/qcom-msm8974-samsung-klte.dts
@@ -12,6 +12,8 @@ / {

 	aliases {
 		serial0 = &blsp1_uart1;
+		sdhc1 = &sdhc_1; /* SDC1 eMMC slot */
+		sdhc2 = &sdhc_2; /* SDC2 SD card slot */
 	};

 	chosen {
@@ -161,6 +163,9 @@ pma8084_l20: l20 {
 					pma8084_l21: l21 {
 						regulator-min-microvolt = <2950000>;
 						regulator-max-microvolt = <2950000>;
+
+						regulator-allow-set-load;
+						regulator-system-load = <200000>;
 					};

 					pma8084_l22: l22 {
@@ -349,6 +354,24 @@ cmd-data {
 			};
 		};

+		sdhc2_pin_a: sdhc2-pin-active {
+			clk-cmd-data {
+				pins = "gpio35", "gpio36", "gpio37", "gpio38",
+					"gpio39", "gpio40";
+				function = "sdc3";
+				drive-strength = <8>;
+				bias-disable;
+			};
+		};
+
+		sdhc2_cd_pin: sdhc2-cd {
+			pins = "gpio62";
+			function = "gpio";
+
+			drive-strength = <2>;
+			bias-disable;
+		};
+
 		sdhc3_pin_a: sdhc3-pin-active {
 			clk {
 				pins = "sdc2_clk";
@@ -422,7 +445,7 @@ int {
 		};
 	};

-	sdhci@f9824900 {
+	sdhc_1: sdhci@f9824900 {
 		status = "ok";

 		vmmc-supply = <&pma8084_l20>;
@@ -435,6 +458,25 @@ sdhci@f9824900 {
 		pinctrl-0 = <&sdhc1_pin_a>;
 	};

+	sdhc_2: sdhci@f9864900 {
+		status = "ok";
+
+		max-frequency = <100000000>;
+
+		vmmc-supply = <&pma8084_l21>;
+		vqmmc-supply = <&pma8084_l13>;
+
+		bus-width = <4>;
+
+		/* cd-gpio is intentionally disabled. If enabled, an SD card
+		 * present during boot is not initialized correctly. Without
+		 * cd-gpios the driver resorts to polling, so hotplug works.
+		 */
+		pinctrl-names = "default";
+		pinctrl-0 = <&sdhc2_pin_a /* &sdhc2_cd_pin */>;
+		// cd-gpios = <&msmgpio 62 GPIO_ACTIVE_LOW>;
+	};
+
 	sdhci@f98a4900 {
 		status = "okay";

--
2.27.0