diff options
Diffstat (limited to 'target/linux/bcm27xx/patches-5.4/950-0946-dt-overlays-Add-PiFace-Digital-Device-Tree-Overlay.patch')
| -rw-r--r-- | target/linux/bcm27xx/patches-5.4/950-0946-dt-overlays-Add-PiFace-Digital-Device-Tree-Overlay.patch | 199 |
1 files changed, 0 insertions, 199 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-0946-dt-overlays-Add-PiFace-Digital-Device-Tree-Overlay.patch b/target/linux/bcm27xx/patches-5.4/950-0946-dt-overlays-Add-PiFace-Digital-Device-Tree-Overlay.patch deleted file mode 100644 index d9a6675f07..0000000000 --- a/target/linux/bcm27xx/patches-5.4/950-0946-dt-overlays-Add-PiFace-Digital-Device-Tree-Overlay.patch +++ /dev/null @@ -1,199 +0,0 @@ -From 296cff78df285c99a52760cbcd896abc37820e06 Mon Sep 17 00:00:00 2001 -From: Thomas Preston <thomas.preston@codethink.co.uk> -Date: Thu, 13 Aug 2020 01:38:35 +0100 -Subject: [PATCH] dt/overlays: Add PiFace Digital Device Tree Overlay - -The PiFace Digital is a convenient breakout board for the Microchip -mcp23s17 SPI GPIO port expander. - -The first eight GPIOs 0..7 (bank A) are connected to eight output -terminals and LEDs, plus two relays on the first two outputs. These -output loads are active-high. - -The next eight GPIOs 8..15 (bank B) are connected to eight input -terminals with four on-board switches connecting them to ground. Inputs -devices are therefore expected to bridge terminals to ground, so the -mcp23s17 pullups are activated for GPIO bank B. - -Signed-off-by: Thomas Preston <thomas.preston@codethink.co.uk> ---- - arch/arm/boot/dts/overlays/Makefile | 1 + - arch/arm/boot/dts/overlays/README | 8 + - .../dts/overlays/pifacedigital-overlay.dts | 144 ++++++++++++++++++ - 3 files changed, 153 insertions(+) - create mode 100644 arch/arm/boot/dts/overlays/pifacedigital-overlay.dts - ---- a/arch/arm/boot/dts/overlays/Makefile -+++ b/arch/arm/boot/dts/overlays/Makefile -@@ -121,6 +121,7 @@ dtbo-$(CONFIG_ARCH_BCM2835) += \ - papirus.dtbo \ - pca953x.dtbo \ - pibell.dtbo \ -+ pifacedigital.dtbo \ - piglow.dtbo \ - piscreen.dtbo \ - piscreen2r.dtbo \ ---- a/arch/arm/boot/dts/overlays/README -+++ b/arch/arm/boot/dts/overlays/README -@@ -1949,6 +1949,14 @@ Params: alsaname Set the - "PiBell") - - -+Name: pifacedigital -+Info: Configures the PiFace Digital mcp23s17 GPIO port expander. -+Load: dtoverlay=pifacedigital,<param>=<val> -+Params: spi-present-mask 8-bit integer, bitmap indicating MCP23S17 SPI0 -+ CS0 address. PiFace Digital supports addresses -+ 0-3, which can be configured with JP1 and JP2. -+ -+ - Name: piglow - Info: Configures the PiGlow by pimoroni.com - Load: dtoverlay=piglow ---- /dev/null -+++ b/arch/arm/boot/dts/overlays/pifacedigital-overlay.dts -@@ -0,0 +1,144 @@ -+// SPDX-License-Identifier: GPL-2.0-only -+/* -+ * PiFace Digital, Device Tree Overlay. -+ * Copyright (C) 2020 Thomas Preston <thomas.preston@codethink.co.uk> -+ * -+ * The PiFace Digital is a convenient breakout board for the Microchip mcp23s17 -+ * SPI GPIO port expander. -+ * -+ * The first eight GPIOs 0..7 (bank A) are connected to eight output terminals -+ * and LEDs, plus two relays on the first two outputs. These output loads are -+ * active-high. -+ * -+ * The next eight GPIOs 8..15 (bank B) are connected to eight input terminals -+ * with four on-board switches connecting them to ground. Inputs devices are -+ * therefore expected to bridge terminals to ground, so the mcp23s17 pullups are -+ * activated for GPIO bank B. -+ * -+ * On PiFace Digital, the mcp23s17 is connected to the Raspberry Pi's SPI0 CS0 -+ * bus. Each SPI bus supports up to eight addressable child devices. The PiFace -+ * Digital only supports addresses 0-4, which can be configured by jumpers JP1 -+ * and JP2. -+ * -+ * You can tell the driver about these jumper configurations with the -+ * spi-present-mask bitmask: -+ * -+ * | JP1 | JP2 | dtoverlay line in /boot/config.txt | -+ * | --- | --- | ------------------------------------------ | -+ * | 0 | 0 | dtoverlay=pifacedigital | -+ * | 0 | 0 | dtoverlay=pifacedigital:spi-present-mask=1 | -+ * | 0 | 1 | dtoverlay=pifacedigital:spi-present-mask=2 | -+ * | 1 | 0 | dtoverlay=pifacedigital:spi-present-mask=4 | -+ * | 1 | 1 | dtoverlay=pifacedigital:spi-present-mask=8 | -+ * -+ * # Example -+ * Set the dtoverlay config in /boot/config.txt and power off the Raspberry Pi: -+ * -+ * $ grep pifacedigital /boot/config.txt -+ * dtoverlay=pifacedigital -+ * $ sudo systemctl poweroff -+ * -+ * Attach the PiFace Digital and power on the Raspberry Pi. -+ * Then use the libgpiod tools to query the device: -+ * -+ * $ sudo apt install gpiod -+ * $ gpiodetect | grep mcp23s17 -+ * gpiochip2 [mcp23s17.0] (16 lines) -+ * -+ * Set GPIO outputs 0, 2 and 5: -+ * -+ * $ gpioset gpiochip2 0=1 2=1 5=1 -+ * -+ * Get GPIO status (input GPIO 8..15 are high, because they are active-low): -+ * -+ * $ gpioget gpiochip2 {8..15} -+ * 1 1 1 1 1 1 1 1 -+ * -+ * And even monitor interrupts: -+ * -+ * $ gpiomon gpiochip2 {8..15} -+ * event: FALLING EDGE offset: 11 timestamp: [1597361662.926741667] -+ * event: RISING EDGE offset: 11 timestamp: [1597361663.062555051] -+ * -+ */ -+ -+/dts-v1/; -+/plugin/; -+ -+/ { -+ compatible = "brcm,bcm2835"; -+ -+ /* Disable exposing /dev/spidev0.0 */ -+ fragment@0 { -+ target = <&spidev0>; -+ __overlay__ { -+ status = "disabled"; -+ }; -+ }; -+ -+ /* Add the PiFace Digital device node to the spi0.0 device. */ -+ fragment@1 { -+ target = <&spi0>; -+ __overlay__ { -+ status = "okay"; -+ #address-cells = <1>; -+ #size-cells = <0>; -+ -+ pfdigital: pifacedigital@0 { -+ compatible = "microchip,mcp23s17"; -+ reg = <0>; -+ -+ /* Set devices present with 8-bit mask. */ -+ microchip,spi-present-mask = <0x01>; -+ spi-max-frequency = <500000>; -+ -+ gpio-controller; -+ #gpio-cells = <2>; -+ -+ /* This device can pass through interrupts. */ -+ interrupt-controller; -+ #interrupt-cells = <2>; -+ -+ /* INTB is connected to GPIO 25. -+ * 0x8 active-low level-sensitive -+ */ -+ interrupts = <25 0x8>; -+ interrupt-parent = <&gpio>; -+ -+ /* Configure pull-ups on bank B GPIOs */ -+ pinctrl-0 = <&pfdigital_irq &pfdigital_pullups>; -+ pinctrl-names = "default"; -+ pfdigital_pullups: pinmux { -+ pins = -+ "gpio8", -+ "gpio9", -+ "gpio10", -+ "gpio11", -+ "gpio12", -+ "gpio13", -+ "gpio14", -+ "gpio15"; -+ bias-pull-up; -+ }; -+ }; -+ }; -+ }; -+ -+ /* PiFace Digital mcp23s17 INTB pin is connected to GPIO 25. The INTB -+ * pin is configured active-low (0 on interrupt), so expect to see -+ * FALLING_EDGE when inputs are bridged to ground (switch is pressed). -+ */ -+ fragment@3 { -+ target = <&gpio>; -+ __overlay__ { -+ pfdigital_irq: pifacedigital_irq { -+ brcm,pins = <25>; -+ brcm,function = <0>; /* input */ -+ }; -+ }; -+ }; -+ -+ __overrides__ { -+ spi-present-mask = <&pfdigital>, "microchip,spi-present-mask:0"; -+ }; -+}; |