path: root/bcm283x-gpio-expander.patch

From patchwork Tue Feb 20 12:19:31 2018
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Subject: [v5,1/5] ARM: bcm2835: sync firmware properties with downstream
From: Baruch Siach <baruch@tkos.co.il>
X-Patchwork-Id: 10229963
Message-Id: <e7d1f1d0789f11d37957a8998bee23d035115aeb.1519128054.git.baruch@tkos.co.il>
To: Linus Walleij <linus.walleij@linaro.org>,
 Dave Stevenson <dave.stevenson@raspberrypi.org>,
 Eric Anholt <eric@anholt.net>, Stefan Wahren <stefan.wahren@i2se.com>
Cc: devicetree@vger.kernel.org, Baruch Siach <baruch@tkos.co.il>,
 linux-gpio@vger.kernel.org, Michael Zoran <mzoran@crowfest.net>,
 Rob Herring <robh+dt@kernel.org>, linux-rpi-kernel@lists.infradead.org,
 Frank Rowand <frowand.list@gmail.com>, linux-arm-kernel@lists.infradead.org
Date: Tue, 20 Feb 2018 14:19:31 +0200

Add latest firmware property tags from the latest Raspberry Pi downstream
kernel. This is needed for the GPIO tags, so we can control the GPIO
multiplexor lines.

Acked-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
---
v4: No change

v3: Add Stefan's ack

v2: No change
---
 include/soc/bcm2835/raspberrypi-firmware.h | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/include/soc/bcm2835/raspberrypi-firmware.h b/include/soc/bcm2835/raspberrypi-firmware.h
index cb979ad90401..50df5b28d2c9 100644
--- a/include/soc/bcm2835/raspberrypi-firmware.h
+++ b/include/soc/bcm2835/raspberrypi-firmware.h
@@ -63,6 +63,7 @@ enum rpi_firmware_property_tag {
 	RPI_FIRMWARE_GET_MIN_VOLTAGE =                        0x00030008,
 	RPI_FIRMWARE_GET_TURBO =                              0x00030009,
 	RPI_FIRMWARE_GET_MAX_TEMPERATURE =                    0x0003000a,
+	RPI_FIRMWARE_GET_STC =                                0x0003000b,
 	RPI_FIRMWARE_ALLOCATE_MEMORY =                        0x0003000c,
 	RPI_FIRMWARE_LOCK_MEMORY =                            0x0003000d,
 	RPI_FIRMWARE_UNLOCK_MEMORY =                          0x0003000e,
@@ -72,12 +73,22 @@ enum rpi_firmware_property_tag {
 	RPI_FIRMWARE_SET_ENABLE_QPU =                         0x00030012,
 	RPI_FIRMWARE_GET_DISPMANX_RESOURCE_MEM_HANDLE =       0x00030014,
 	RPI_FIRMWARE_GET_EDID_BLOCK =                         0x00030020,
+	RPI_FIRMWARE_GET_CUSTOMER_OTP =                       0x00030021,
 	RPI_FIRMWARE_GET_DOMAIN_STATE =                       0x00030030,
 	RPI_FIRMWARE_SET_CLOCK_STATE =                        0x00038001,
 	RPI_FIRMWARE_SET_CLOCK_RATE =                         0x00038002,
 	RPI_FIRMWARE_SET_VOLTAGE =                            0x00038003,
 	RPI_FIRMWARE_SET_TURBO =                              0x00038009,
+	RPI_FIRMWARE_SET_CUSTOMER_OTP =                       0x00038021,
 	RPI_FIRMWARE_SET_DOMAIN_STATE =                       0x00038030,
+	RPI_FIRMWARE_GET_GPIO_STATE =                         0x00030041,
+	RPI_FIRMWARE_SET_GPIO_STATE =                         0x00038041,
+	RPI_FIRMWARE_SET_SDHOST_CLOCK =                       0x00038042,
+	RPI_FIRMWARE_GET_GPIO_CONFIG =                        0x00030043,
+	RPI_FIRMWARE_SET_GPIO_CONFIG =                        0x00038043,
+	RPI_FIRMWARE_GET_PERIPH_REG =                         0x00030045,
+	RPI_FIRMWARE_SET_PERIPH_REG =                         0x00038045,
+
 
 	/* Dispmanx TAGS */
 	RPI_FIRMWARE_FRAMEBUFFER_ALLOCATE =                   0x00040001,
@@ -91,6 +102,8 @@ enum rpi_firmware_property_tag {
 	RPI_FIRMWARE_FRAMEBUFFER_GET_VIRTUAL_OFFSET =         0x00040009,
 	RPI_FIRMWARE_FRAMEBUFFER_GET_OVERSCAN =               0x0004000a,
 	RPI_FIRMWARE_FRAMEBUFFER_GET_PALETTE =                0x0004000b,
+	RPI_FIRMWARE_FRAMEBUFFER_GET_TOUCHBUF =               0x0004000f,
+	RPI_FIRMWARE_FRAMEBUFFER_GET_GPIOVIRTBUF =            0x00040010,
 	RPI_FIRMWARE_FRAMEBUFFER_RELEASE =                    0x00048001,
 	RPI_FIRMWARE_FRAMEBUFFER_TEST_PHYSICAL_WIDTH_HEIGHT = 0x00044003,
 	RPI_FIRMWARE_FRAMEBUFFER_TEST_VIRTUAL_WIDTH_HEIGHT =  0x00044004,
@@ -100,6 +113,7 @@ enum rpi_firmware_property_tag {
 	RPI_FIRMWARE_FRAMEBUFFER_TEST_VIRTUAL_OFFSET =        0x00044009,
 	RPI_FIRMWARE_FRAMEBUFFER_TEST_OVERSCAN =              0x0004400a,
 	RPI_FIRMWARE_FRAMEBUFFER_TEST_PALETTE =               0x0004400b,
+	RPI_FIRMWARE_FRAMEBUFFER_TEST_VSYNC =                 0x0004400e,
 	RPI_FIRMWARE_FRAMEBUFFER_SET_PHYSICAL_WIDTH_HEIGHT =  0x00048003,
 	RPI_FIRMWARE_FRAMEBUFFER_SET_VIRTUAL_WIDTH_HEIGHT =   0x00048004,
 	RPI_FIRMWARE_FRAMEBUFFER_SET_DEPTH =                  0x00048005,
@@ -108,6 +122,10 @@ enum rpi_firmware_property_tag {
 	RPI_FIRMWARE_FRAMEBUFFER_SET_VIRTUAL_OFFSET =         0x00048009,
 	RPI_FIRMWARE_FRAMEBUFFER_SET_OVERSCAN =               0x0004800a,
 	RPI_FIRMWARE_FRAMEBUFFER_SET_PALETTE =                0x0004800b,
+	RPI_FIRMWARE_FRAMEBUFFER_SET_TOUCHBUF =               0x0004801f,
+	RPI_FIRMWARE_FRAMEBUFFER_SET_GPIOVIRTBUF =            0x00048020,
+	RPI_FIRMWARE_FRAMEBUFFER_SET_VSYNC =                  0x0004800e,
+	RPI_FIRMWARE_FRAMEBUFFER_SET_BACKLIGHT =              0x0004800f,
 
 	RPI_FIRMWARE_VCHIQ_INIT =                             0x00048010,
 
From patchwork Tue Feb 20 12:19:32 2018
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Subject: [v5,2/5] dt-bindings: gpio: add raspberry pi GPIO expander binding
From: Baruch Siach <baruch@tkos.co.il>
X-Patchwork-Id: 10229965
Message-Id: <f400b48cbcd8a138c39d4e8f63d6c1f569090dcc.1519128054.git.baruch@tkos.co.il>
To: Linus Walleij <linus.walleij@linaro.org>,
 Dave Stevenson <dave.stevenson@raspberrypi.org>,
 Eric Anholt <eric@anholt.net>, Stefan Wahren <stefan.wahren@i2se.com>
Cc: devicetree@vger.kernel.org, Baruch Siach <baruch@tkos.co.il>,
 linux-gpio@vger.kernel.org, Michael Zoran <mzoran@crowfest.net>,
 Rob Herring <robh+dt@kernel.org>, linux-rpi-kernel@lists.infradead.org,
 Frank Rowand <frowand.list@gmail.com>, linux-arm-kernel@lists.infradead.org
Date: Tue, 20 Feb 2018 14:19:32 +0200

The Raspberry Pi 3 GPIO expander is controlled by the VC4 firmware over
I2C. The firmware mailbox interface allows the ARM core to control the
GPIO lines.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Reviewed-by: Rob Herring <robh@kernel.org>
---
v5:
  * Remove the 'firmware' property
  * Note that the gpio node is a child of the firmware node

v4:
  * Move the example gpio node under the firmware node
  * Rename gpio node name to plain 'gpio'

v3:
  * Rename node name.

v2:
  * Rename compatible string to raspberrypi,firmware-gpio
---
 .../bindings/gpio/raspberrypi,firmware-gpio.txt    | 30 ++++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/gpio/raspberrypi,firmware-gpio.txt

diff --git a/Documentation/devicetree/bindings/gpio/raspberrypi,firmware-gpio.txt b/Documentation/devicetree/bindings/gpio/raspberrypi,firmware-gpio.txt
new file mode 100644
index 000000000000..ce97265e23ba
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/raspberrypi,firmware-gpio.txt
@@ -0,0 +1,30 @@
+Raspberry Pi GPIO expander
+
+The Raspberry Pi 3 GPIO expander is controlled by the VC4 firmware. The
+firmware exposes a mailbox interface that allows the ARM core to control the
+GPIO lines on the expander.
+
+The Raspberry Pi GPIO expander node must be a child node of the Raspberry Pi
+firmware node.
+
+Required properties:
+
+- compatible : Should be "raspberrypi,firmware-gpio"
+- gpio-controller : Marks the device node as a gpio controller
+- #gpio-cells : Should be two.  The first cell is the pin number, and
+  the second cell is used to specify the gpio polarity:
+  0 = active high
+  1 = active low
+
+Example:
+
+firmware: firmware-rpi {
+	compatible = "raspberrypi,bcm2835-firmware";
+	mboxes = <&mailbox>;
+
+	expgpio: gpio {
+		 compatible = "raspberrypi,firmware-gpio";
+		 gpio-controller;
+		 #gpio-cells = <2>;
+	 };
+};
From patchwork Tue Feb 20 12:19:33 2018
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Subject: [v5,
 3/5] gpio: raspberrypi-exp: Driver for RPi3 GPIO expander via mailbox
 service
From: Baruch Siach <baruch@tkos.co.il>
X-Patchwork-Id: 10229967
Message-Id: <8c34f287ee72b340fa9d693aa0e304b25541c74c.1519128054.git.baruch@tkos.co.il>
To: Linus Walleij <linus.walleij@linaro.org>,
 Dave Stevenson <dave.stevenson@raspberrypi.org>,
 Eric Anholt <eric@anholt.net>, Stefan Wahren <stefan.wahren@i2se.com>
Cc: devicetree@vger.kernel.org, Baruch Siach <baruch@tkos.co.il>,
 linux-gpio@vger.kernel.org, Michael Zoran <mzoran@crowfest.net>,
 Rob Herring <robh+dt@kernel.org>, linux-rpi-kernel@lists.infradead.org,
 Frank Rowand <frowand.list@gmail.com>, linux-arm-kernel@lists.infradead.org
Date: Tue, 20 Feb 2018 14:19:33 +0200

From: Dave Stevenson <dave.stevenson@raspberrypi.org>

Pi3 and Compute Module 3 have a GPIO expander that the
VPU communicates with.
There is a mailbox service that now allows control of this
expander, so add a kernel driver that can make use of it.

Reviewed-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
---
v5:
  * Use the parent node to find the firmware

v4:
  * Don't set the .owner driver field
  * Add Stefan's review tag

v3:
  * Tweak Kconfig driver prompt
  * Make GPIO_RASPBERRYPI_EXP tristate
  * Make COMPILE_TEST independent of RASPBERRYPI_FIRMWARE
  * Remove redundant DMA header
  * Use less code lines for dev_err()
  * Check rpi_exp_gpio_get_polarity() return value
  * Remove redundant platform_set_drvdata() call

v2:
  * Rename driver to gpio-raspberrypi-exp
  * Populate the gpiochip parent device pointer
  * Use macro for the mailbox base GPIO number
  * Drop linux/gpio.h and GPIOF_DIR_*
  * Check and print firmware error value
  * Use devm_gpiochip_add_data(); drop .remove
  * A few more minor tweaks
---
 drivers/gpio/Kconfig                |   9 ++
 drivers/gpio/Makefile               |   1 +
 drivers/gpio/gpio-raspberrypi-exp.c | 252 ++++++++++++++++++++++++++++++++++++
 3 files changed, 262 insertions(+)
 create mode 100644 drivers/gpio/gpio-raspberrypi-exp.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 8dbb2280538d..fd0562a37f68 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -122,6 +122,15 @@ config GPIO_ATH79
 	  Select this option to enable GPIO driver for
 	  Atheros AR71XX/AR724X/AR913X SoC devices.
 
+config GPIO_RASPBERRYPI_EXP
+	tristate "Raspberry Pi 3 GPIO Expander"
+	default RASPBERRYPI_FIRMWARE
+	depends on OF_GPIO
+	depends on (ARCH_BCM2835 && RASPBERRYPI_FIRMWARE) || COMPILE_TEST
+	help
+	  Turn on GPIO support for the expander on Raspberry Pi 3 boards, using
+	  the firmware mailbox to communicate with VideoCore on BCM283x chips.
+
 config GPIO_BCM_KONA
 	bool "Broadcom Kona GPIO"
 	depends on OF_GPIO && (ARCH_BCM_MOBILE || COMPILE_TEST)
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index cccb0d40846c..76dc0a02bd56 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -32,6 +32,7 @@ obj-$(CONFIG_GPIO_AMDPT)	+= gpio-amdpt.o
 obj-$(CONFIG_GPIO_ARIZONA)	+= gpio-arizona.o
 obj-$(CONFIG_GPIO_ATH79)	+= gpio-ath79.o
 obj-$(CONFIG_GPIO_ASPEED)	+= gpio-aspeed.o
+obj-$(CONFIG_GPIO_RASPBERRYPI_EXP)	+= gpio-raspberrypi-exp.o
 obj-$(CONFIG_GPIO_BCM_KONA)	+= gpio-bcm-kona.o
 obj-$(CONFIG_GPIO_BD9571MWV)	+= gpio-bd9571mwv.o
 obj-$(CONFIG_GPIO_BRCMSTB)	+= gpio-brcmstb.o
diff --git a/drivers/gpio/gpio-raspberrypi-exp.c b/drivers/gpio/gpio-raspberrypi-exp.c
new file mode 100644
index 000000000000..d6d36d537e37
--- /dev/null
+++ b/drivers/gpio/gpio-raspberrypi-exp.c
@@ -0,0 +1,252 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  Raspberry Pi 3 expander GPIO driver
+ *
+ *  Uses the firmware mailbox service to communicate with the
+ *  GPIO expander on the VPU.
+ *
+ *  Copyright (C) 2017 Raspberry Pi Trading Ltd.
+ */
+
+#include <linux/err.h>
+#include <linux/gpio/driver.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <soc/bcm2835/raspberrypi-firmware.h>
+
+#define MODULE_NAME "raspberrypi-exp-gpio"
+#define NUM_GPIO 8
+
+#define RPI_EXP_GPIO_BASE	128
+
+#define RPI_EXP_GPIO_DIR_IN	0
+#define RPI_EXP_GPIO_DIR_OUT	1
+
+struct rpi_exp_gpio {
+	struct gpio_chip gc;
+	struct rpi_firmware *fw;
+};
+
+/* VC4 firmware mailbox interface data structures */
+
+struct gpio_set_config {
+	u32 gpio;
+	u32 direction;
+	u32 polarity;
+	u32 term_en;
+	u32 term_pull_up;
+	u32 state;
+};
+
+struct gpio_get_config {
+	u32 gpio;
+	u32 direction;
+	u32 polarity;
+	u32 term_en;
+	u32 term_pull_up;
+};
+
+struct gpio_get_set_state {
+	u32 gpio;
+	u32 state;
+};
+
+static int rpi_exp_gpio_get_polarity(struct gpio_chip *gc, unsigned int off)
+{
+	struct rpi_exp_gpio *gpio;
+	struct gpio_get_config get;
+	int ret;
+
+	gpio = gpiochip_get_data(gc);
+
+	get.gpio = off + RPI_EXP_GPIO_BASE;	/* GPIO to update */
+
+	ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_GET_GPIO_CONFIG,
+				    &get, sizeof(get));
+	if (ret || get.gpio != 0) {
+		dev_err(gc->parent, "Failed to get GPIO %u config (%d %x)\n",
+			off, ret, get.gpio);
+		return ret ? ret : -EIO;
+	}
+	return get.polarity;
+}
+
+static int rpi_exp_gpio_dir_in(struct gpio_chip *gc, unsigned int off)
+{
+	struct rpi_exp_gpio *gpio;
+	struct gpio_set_config set_in;
+	int ret;
+
+	gpio = gpiochip_get_data(gc);
+
+	set_in.gpio = off + RPI_EXP_GPIO_BASE;	/* GPIO to update */
+	set_in.direction = RPI_EXP_GPIO_DIR_IN;
+	set_in.term_en = 0;		/* termination disabled */
+	set_in.term_pull_up = 0;	/* n/a as termination disabled */
+	set_in.state = 0;		/* n/a as configured as an input */
+
+	ret = rpi_exp_gpio_get_polarity(gc, off);
+	if (ret < 0)
+		return ret;
+	set_in.polarity = ret;		/* Retain existing setting */
+
+	ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_SET_GPIO_CONFIG,
+				    &set_in, sizeof(set_in));
+	if (ret || set_in.gpio != 0) {
+		dev_err(gc->parent, "Failed to set GPIO %u to input (%d %x)\n",
+			off, ret, set_in.gpio);
+		return ret ? ret : -EIO;
+	}
+	return 0;
+}
+
+static int rpi_exp_gpio_dir_out(struct gpio_chip *gc, unsigned int off, int val)
+{
+	struct rpi_exp_gpio *gpio;
+	struct gpio_set_config set_out;
+	int ret;
+
+	gpio = gpiochip_get_data(gc);
+
+	set_out.gpio = off + RPI_EXP_GPIO_BASE;	/* GPIO to update */
+	set_out.direction = RPI_EXP_GPIO_DIR_OUT;
+	set_out.term_en = 0;		/* n/a as an output */
+	set_out.term_pull_up = 0;	/* n/a as termination disabled */
+	set_out.state = val;		/* Output state */
+
+	ret = rpi_exp_gpio_get_polarity(gc, off);
+	if (ret < 0)
+		return ret;
+	set_out.polarity = ret;		/* Retain existing setting */
+
+	ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_SET_GPIO_CONFIG,
+				    &set_out, sizeof(set_out));
+	if (ret || set_out.gpio != 0) {
+		dev_err(gc->parent, "Failed to set GPIO %u to output (%d %x)\n",
+			off, ret, set_out.gpio);
+		return ret ? ret : -EIO;
+	}
+	return 0;
+}
+
+static int rpi_exp_gpio_get_direction(struct gpio_chip *gc, unsigned int off)
+{
+	struct rpi_exp_gpio *gpio;
+	struct gpio_get_config get;
+	int ret;
+
+	gpio = gpiochip_get_data(gc);
+
+	get.gpio = off + RPI_EXP_GPIO_BASE;	/* GPIO to update */
+
+	ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_GET_GPIO_CONFIG,
+				    &get, sizeof(get));
+	if (ret || get.gpio != 0) {
+		dev_err(gc->parent,
+			"Failed to get GPIO %u config (%d %x)\n", off, ret,
+			get.gpio);
+		return ret ? ret : -EIO;
+	}
+	return !get.direction;
+}
+
+static int rpi_exp_gpio_get(struct gpio_chip *gc, unsigned int off)
+{
+	struct rpi_exp_gpio *gpio;
+	struct gpio_get_set_state get;
+	int ret;
+
+	gpio = gpiochip_get_data(gc);
+
+	get.gpio = off + RPI_EXP_GPIO_BASE;	/* GPIO to update */
+	get.state = 0;		/* storage for returned value */
+
+	ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_GET_GPIO_STATE,
+					 &get, sizeof(get));
+	if (ret || get.gpio != 0) {
+		dev_err(gc->parent,
+			"Failed to get GPIO %u state (%d %x)\n", off, ret,
+			get.gpio);
+		return ret ? ret : -EIO;
+	}
+	return !!get.state;
+}
+
+static void rpi_exp_gpio_set(struct gpio_chip *gc, unsigned int off, int val)
+{
+	struct rpi_exp_gpio *gpio;
+	struct gpio_get_set_state set;
+	int ret;
+
+	gpio = gpiochip_get_data(gc);
+
+	set.gpio = off + RPI_EXP_GPIO_BASE;	/* GPIO to update */
+	set.state = val;	/* Output state */
+
+	ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_SET_GPIO_STATE,
+					 &set, sizeof(set));
+	if (ret || set.gpio != 0)
+		dev_err(gc->parent,
+			"Failed to set GPIO %u state (%d %x)\n", off, ret,
+			set.gpio);
+}
+
+static int rpi_exp_gpio_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct device_node *fw_node;
+	struct rpi_firmware *fw;
+	struct rpi_exp_gpio *rpi_gpio;
+
+	fw_node = of_get_parent(np);
+	if (!fw_node) {
+		dev_err(dev, "Missing firmware node\n");
+		return -ENOENT;
+	}
+
+	fw = rpi_firmware_get(fw_node);
+	if (!fw)
+		return -EPROBE_DEFER;
+
+	rpi_gpio = devm_kzalloc(dev, sizeof(*rpi_gpio), GFP_KERNEL);
+	if (!rpi_gpio)
+		return -ENOMEM;
+
+	rpi_gpio->fw = fw;
+	rpi_gpio->gc.parent = dev;
+	rpi_gpio->gc.label = MODULE_NAME;
+	rpi_gpio->gc.owner = THIS_MODULE;
+	rpi_gpio->gc.of_node = np;
+	rpi_gpio->gc.base = -1;
+	rpi_gpio->gc.ngpio = NUM_GPIO;
+
+	rpi_gpio->gc.direction_input = rpi_exp_gpio_dir_in;
+	rpi_gpio->gc.direction_output = rpi_exp_gpio_dir_out;
+	rpi_gpio->gc.get_direction = rpi_exp_gpio_get_direction;
+	rpi_gpio->gc.get = rpi_exp_gpio_get;
+	rpi_gpio->gc.set = rpi_exp_gpio_set;
+	rpi_gpio->gc.can_sleep = true;
+
+	return devm_gpiochip_add_data(dev, &rpi_gpio->gc, rpi_gpio);
+}
+
+static const struct of_device_id rpi_exp_gpio_ids[] = {
+	{ .compatible = "raspberrypi,firmware-gpio" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, rpi_exp_gpio_ids);
+
+static struct platform_driver rpi_exp_gpio_driver = {
+	.driver	= {
+		.name		= MODULE_NAME,
+		.of_match_table	= of_match_ptr(rpi_exp_gpio_ids),
+	},
+	.probe	= rpi_exp_gpio_probe,
+};
+module_platform_driver(rpi_exp_gpio_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Dave Stevenson <dave.stevenson@raspberrypi.org>");
+MODULE_DESCRIPTION("Raspberry Pi 3 expander GPIO driver");
+MODULE_ALIAS("platform:rpi-exp-gpio");
From patchwork Tue Feb 20 12:19:34 2018
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MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Subject: [v5,4/5] ARM: dts: bcm2835: make the firmware node into a bus
From: Baruch Siach <baruch@tkos.co.il>
X-Patchwork-Id: 10229961
Message-Id: <43f9082a6835df6d7bcd3e16d79db687c52826d2.1519128054.git.baruch@tkos.co.il>
To: Linus Walleij <linus.walleij@linaro.org>,
 Dave Stevenson <dave.stevenson@raspberrypi.org>,
 Eric Anholt <eric@anholt.net>, Stefan Wahren <stefan.wahren@i2se.com>
Cc: devicetree@vger.kernel.org, Baruch Siach <baruch@tkos.co.il>,
 linux-gpio@vger.kernel.org, Michael Zoran <mzoran@crowfest.net>,
 Rob Herring <robh+dt@kernel.org>, linux-rpi-kernel@lists.infradead.org,
 Frank Rowand <frowand.list@gmail.com>, linux-arm-kernel@lists.infradead.org
Date: Tue, 20 Feb 2018 14:19:34 +0200

This allows adding devices for which the firmware exposes control interface
via the mailbox. An example of such device is the GPIO expander.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
---
v4: New patch in this series
---
 arch/arm/boot/dts/bcm2835-rpi.dtsi | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/bcm2835-rpi.dtsi b/arch/arm/boot/dts/bcm2835-rpi.dtsi
index e36c392a2b8f..0198bd46ef7c 100644
--- a/arch/arm/boot/dts/bcm2835-rpi.dtsi
+++ b/arch/arm/boot/dts/bcm2835-rpi.dtsi
@@ -18,7 +18,9 @@
 
 	soc {
 		firmware: firmware {
-			compatible = "raspberrypi,bcm2835-firmware";
+			compatible = "raspberrypi,bcm2835-firmware", "simple-bus";
+			#address-cells = <0>;
+			#size-cells = <0>;
 			mboxes = <&mailbox>;
 		};
 
From patchwork Tue Feb 20 12:19:35 2018
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Subject: [v5,5/5] ARM: dts: bcm2837-rpi-3-b: add GPIO expander
From: Baruch Siach <baruch@tkos.co.il>
X-Patchwork-Id: 10229995
Message-Id: <a6d59692dc4847e0b1639a26542e28c95ad5240f.1519128054.git.baruch@tkos.co.il>
To: Linus Walleij <linus.walleij@linaro.org>,
 Dave Stevenson <dave.stevenson@raspberrypi.org>,
 Eric Anholt <eric@anholt.net>, Stefan Wahren <stefan.wahren@i2se.com>
Cc: devicetree@vger.kernel.org, Baruch Siach <baruch@tkos.co.il>,
 linux-gpio@vger.kernel.org, Michael Zoran <mzoran@crowfest.net>,
 Rob Herring <robh+dt@kernel.org>, linux-rpi-kernel@lists.infradead.org,
 Frank Rowand <frowand.list@gmail.com>, linux-arm-kernel@lists.infradead.org
Date: Tue, 20 Feb 2018 14:19:35 +0200

Add a description of the RPi3 GPIO expander that the VC4 firmware controls.

Acked-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
---
v5:
  * Drop the 'firmware' property

v4:
  * Move the gpio node under the firmware node
  * Rename the gpio node to plain 'gpio'
  * Add Stefan's ack

v3:
  * List GPIO names one per line.

v2:
  * Move GPIO expander node out of the soc container
  * Rename compatible string
  * Add gpio-line-names property
---
 arch/arm/boot/dts/bcm2837-rpi-3-b.dts | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/arch/arm/boot/dts/bcm2837-rpi-3-b.dts b/arch/arm/boot/dts/bcm2837-rpi-3-b.dts
index 3e4ed7c5b0b3..0b31d995a066 100644
--- a/arch/arm/boot/dts/bcm2837-rpi-3-b.dts
+++ b/arch/arm/boot/dts/bcm2837-rpi-3-b.dts
@@ -25,6 +25,23 @@
 	};
 };
 
+&firmware {
+	expgpio: gpio {
+		compatible = "raspberrypi,firmware-gpio";
+		gpio-controller;
+		#gpio-cells = <2>;
+		gpio-line-names = "BT_ON",
+				  "WL_ON",
+				  "STATUS_LED",
+				  "LAN_RUN",
+				  "HPD_N",
+				  "CAM_GPIO0",
+				  "CAM_GPIO1",
+				  "PWR_LOW_N";
+		status = "okay";
+	};
+};
+
 /* uart0 communicates with the BT module */
 &uart0 {
 	pinctrl-names = "default";