openwrt/target/linux/brcm2708/patches-4.14/950-0233-overlays-Rework-sdio-overlays-to-allow-polling.patch

From 152d226fd2eff1fdc1f8881287bf1a7d4560b27e Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.org>
Date: Mon, 26 Feb 2018 19:46:32 +0000
Subject: [PATCH 233/454] overlays: Rework sdio overlays to allow polling

MMC/SD interfaces support a DT property (non-removable) that disables
the usual polling required to detect card removal for a configuration
that doesn't have hardware card presence detection. This property is
required for the on-board SDIO WiFi interface, but other uses of the
interface may want the polling to be re-enabled.

'non-removable' is a boolean DT property - true if present, false if
absent - and the overlay mechanism does not allow a property in the
base DTB to be deleted, so if the base DTB has non-removable set
(which is true for all WiFi-equipped Pis) then an overlay cannot
unset it.

Modify the SDIO overlays to work around this problem by disabling
the mmc node and adding a clone to which non-removable may
optionally be added.

N.B. The default state of poll_once is still true, and the overlay
does include a non-removable property, but setting poll_once to false
("off") will remove the property from the overlay before it is applied.

See: https://github.com/raspberrypi/linux/issues/2401

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
 .../boot/dts/overlays/sdio-1bit-overlay.dts   | 40 +++++++++++++-----
 arch/arm/boot/dts/overlays/sdio-overlay.dts   | 41 ++++++++++++++-----
 2 files changed, 59 insertions(+), 22 deletions(-)

--- a/arch/arm/boot/dts/overlays/sdio-1bit-overlay.dts
+++ b/arch/arm/boot/dts/overlays/sdio-1bit-overlay.dts
@@ -8,21 +8,39 @@
 
 	fragment@0 {
 		target = <&mmc>;
-		sdio_mmc: __overlay__ {
-			compatible = "brcm,bcm2835-mmc";
-			pinctrl-names = "default";
-			pinctrl-0 = <&sdio_pins>;
-			non-removable;
-			bus-width = <1>;
-			brcm,overclock-50 = <0>;
-			status = "okay";
+		__overlay__ {
+			status = "disabled";
 		};
 	};
 
 	fragment@1 {
+		target = <&soc>;
+		__overlay__ {
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			sdio_1bit: sdio@7e300000 {
+				compatible = "brcm,bcm2835-mmc",
+					     "brcm,bcm2835-sdhci";
+				reg = <0x7e300000 0x100>;
+				interrupts = <2 30>;
+				clocks = <&clocks 28/*BCM2835_CLOCK_EMMC*/>;
+				dmas = <&dma 11>;
+				dma-names = "rx-tx";
+				brcm,overclock-50 = <0>;
+				status = "okay";
+				pinctrl-names = "default";
+				pinctrl-0 = <&sdio_1bit_pins>;
+				non-removable;
+				bus-width = <1>;
+			};
+		};
+	};
+
+	fragment@2 {
 		target = <&gpio>;
 		__overlay__ {
-			sdio_pins: sdio_pins {
+			sdio_1bit_pins: sdio_1bit_pins {
 				brcm,pins = <22 23 24 25>;
 				brcm,function = <7>; /* ALT3 = SD1 */
 				brcm,pull = <0 2 2 2>;
@@ -31,7 +49,7 @@
 	};
 
 	__overrides__ {
-		poll_once = <&sdio_mmc>,"non-removable?";
-		sdio_overclock = <&sdio_mmc>,"brcm,overclock-50:0";
+		poll_once = <&sdio_1bit>,"non-removable?";
+		sdio_overclock = <&sdio_1bit>,"brcm,overclock-50:0";
 	};
 };
--- a/arch/arm/boot/dts/overlays/sdio-overlay.dts
+++ b/arch/arm/boot/dts/overlays/sdio-overlay.dts
@@ -8,20 +8,39 @@
 
 	fragment@0 {
 		target = <&mmc>;
-		sdio_mmc: __overlay__ {
-			pinctrl-names = "default";
-			pinctrl-0 = <&sdio_pins>;
-			non-removable;
-			bus-width = <4>;
-			brcm,overclock-50 = <0>;
-			status = "okay";
+		__overlay__ {
+			status = "disabled";
 		};
 	};
 
 	fragment@1 {
+		target = <&soc>;
+		__overlay__ {
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			sdio_ovl: sdio@7e300000 {
+				compatible = "brcm,bcm2835-mmc",
+					     "brcm,bcm2835-sdhci";
+				reg = <0x7e300000 0x100>;
+				interrupts = <2 30>;
+				clocks = <&clocks 28/*BCM2835_CLOCK_EMMC*/>;
+				dmas = <&dma 11>;
+				dma-names = "rx-tx";
+				brcm,overclock-50 = <0>;
+				status = "okay";
+				pinctrl-names = "default";
+				pinctrl-0 = <&sdio_ovl_pins>;
+				non-removable;
+				bus-width = <1>;
+			};
+		};
+	};
+
+	fragment@2 {
 		target = <&gpio>;
 		__overlay__ {
-			sdio_pins: sdio_pins {
+			sdio_ovl_pins: sdio_ovl_pins {
 				brcm,pins = <22 23 24 25 26 27>;
 				brcm,function = <7>; /* ALT3 = SD1 */
 				brcm,pull = <0 2 2 2 2 2>;
@@ -30,8 +49,8 @@
 	};
 
 	__overrides__ {
-		poll_once = <&sdio_mmc>,"non-removable?";
-		bus_width = <&sdio_mmc>,"bus-width:0";
-		sdio_overclock = <&sdio_mmc>,"brcm,overclock-50:0";
+		poll_once = <&sdio_ovl>,"non-removable?";
+		bus_width = <&sdio_ovl>,"bus-width:0";
+		sdio_overclock = <&sdio_ovl>,"brcm,overclock-50:0";
 	};
 };