ARM: dts: add Raspberry Pi 3 A+

The Raspberry Pi 3 A+ is similar to the Pi 3 B+ but has only 512 MB RAM,
1 USB 2.0 port and no Ethernet.

Compared to the Raspberry Pi 3 B it isn't possible to control BT_ON and
WL_ON separately.
Signed-off-by: NStefan Wahren <stefan.wahren@i2se.com>
Acked-by: NEric Anholt <eric@anholt.net>

arch/arm/boot/dts/Makefile

@@ -79,6 +79,7 @@ dtb-$(CONFIG_ARCH_BCM2835) += \
 	bcm2835-rpi-a-plus.dtb \
 	bcm2835-rpi-cm1-io1.dtb \
 	bcm2836-rpi-2-b.dtb \
+	bcm2837-rpi-3-a-plus.dtb \
 	bcm2837-rpi-3-b.dtb \
 	bcm2837-rpi-3-b-plus.dtb \
 	bcm2837-rpi-cm3-io3.dtb \

arch/arm/boot/dts/bcm2837-rpi-3-a-plus.dts

+// SPDX-License-Identifier: GPL-2.0
+/dts-v1/;
+#include "bcm2837.dtsi"
+#include "bcm2836-rpi.dtsi"
+#include "bcm283x-rpi-usb-host.dtsi"
+
+/ {
+	compatible = "raspberrypi,3-model-a-plus", "brcm,bcm2837";
+	model = "Raspberry Pi 3 Model A+";
+
+	chosen {
+		/* 8250 auxiliary UART instead of pl011 */
+		stdout-path = "serial1:115200n8";
+	};
+
+	memory {
+		reg = <0 0x20000000>;
+	};
+
+	leds {
+		act {
+			gpios = <&gpio 29 GPIO_ACTIVE_HIGH>;
+		};
+
+		pwr {
+			label = "PWR";
+			gpios = <&expgpio 2 GPIO_ACTIVE_LOW>;
+		};
+	};
+};
+
+&firmware {
+	expgpio: gpio {
+		compatible = "raspberrypi,firmware-gpio";
+		gpio-controller;
+		#gpio-cells = <2>;
+		gpio-line-names = "",
+				  "BT_WL_ON",
+				  "STATUS_LED_R",
+				  "",
+				  "",
+				  "CAM_GPIO0",
+				  "CAM_GPIO1",
+				  "";
+		status = "okay";
+	};
+};
+
+&gpio {
+	/*
+	 * This is mostly based on the official GPU firmware DT blob.
+	 *
+	 * Legend:
+	 * "NC" = not connected (no rail from the SoC)
+	 * "FOO" = GPIO line named "FOO" on the schematic
+	 * "FOO_N" = GPIO line named "FOO" on schematic, active low
+	 */
+	gpio-line-names = "ID_SDA",
+			  "ID_SCL",
+			  "SDA1",
+			  "SCL1",
+			  "GPIO_GCLK",
+			  "GPIO5",
+			  "GPIO6",
+			  "SPI_CE1_N",
+			  "SPI_CE0_N",
+			  "SPI_MISO",
+			  "SPI_MOSI",
+			  "SPI_SCLK",
+			  "GPIO12",
+			  "GPIO13",
+			  /* Serial port */
+			  "TXD1",
+			  "RXD1",
+			  "GPIO16",
+			  "GPIO17",
+			  "GPIO18",
+			  "GPIO19",
+			  "GPIO20",
+			  "GPIO21",
+			  "GPIO22",
+			  "GPIO23",
+			  "GPIO24",
+			  "GPIO25",
+			  "GPIO26",
+			  "GPIO27",
+			  "HDMI_HPD_N",
+			  "STATUS_LED_G",
+			  /* Used by BT module */
+			  "CTS0",
+			  "RTS0",
+			  "TXD0",
+			  "RXD0",
+			  /* Used by Wifi */
+			  "SD1_CLK",
+			  "SD1_CMD",
+			  "SD1_DATA0",
+			  "SD1_DATA1",
+			  "SD1_DATA2",
+			  "SD1_DATA3",
+			  "PWM0_OUT",
+			  "PWM1_OUT",
+			  "", /* GPIO42 */
+			  "WIFI_CLK",
+			  "SDA0",
+			  "SCL0",
+			  "SMPS_SCL",
+			  "SMPS_SDA",
+			  /* Used by SD Card */
+			  "SD_CLK_R",
+			  "SD_CMD_R",
+			  "SD_DATA0_R",
+			  "SD_DATA1_R",
+			  "SD_DATA2_R",
+			  "SD_DATA3_R";
+};
+
+&hdmi {
+	hpd-gpios = <&gpio 28 GPIO_ACTIVE_LOW>;
+};
+
+&pwm {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pwm0_gpio40 &pwm1_gpio41>;
+	status = "okay";
+};
+
+/*
+ * SDHCI is used to control the SDIO for wireless
+ *
+ * WL_REG_ON and BT_REG_ON of the CYW43455 Wifi/BT module are driven
+ * by a single GPIO. We can't give GPIO control to one of the drivers,
+ * otherwise the other part would get unexpectedly disturbed.
+ */
+&sdhci {
+	#address-cells = <1>;
+	#size-cells = <0>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&emmc_gpio34>;
+	status = "okay";
+	bus-width = <4>;
+	non-removable;
+
+	brcmf: wifi@1 {
+		reg = <1>;
+		compatible = "brcm,bcm4329-fmac";
+	};
+};
+
+/* SDHOST is used to drive the SD card */
+&sdhost {
+	pinctrl-names = "default";
+	pinctrl-0 = <&sdhost_gpio48>;
+	status = "okay";
+	bus-width = <4>;
+};
+
+/* uart0 communicates with the BT module */
+&uart0 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&uart0_ctsrts_gpio30 &uart0_gpio32 &gpclk2_gpio43>;
+	status = "okay";
+
+	bluetooth {
+		compatible = "brcm,bcm43438-bt";
+		max-speed = <2000000>;
+	};
+};
+
+/* uart1 is mapped to the pin header */
+&uart1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&uart1_gpio14>;
+	status = "okay";
+};