The Raspberry Pi 3 has a GPIO expander that controls, among others, the activity LED, and the camera connector GPIOs. The GPIO expander on an I2C bus that is not directly controlled from the ARM core. The VC4 firmware controls the I2C bus, and allows the ARM core to set/get GPIO settings over its mailbox interface. This series adds support for the RPi3 expander. The driver is ported from the downstream kernel at https://github.com/raspberrypi/linux/, branch rpi-4.9.y. This series is based on commit v4.16-rc2. Changes in v5: * Remove the 'firmware' property from the binding as suggested by Rob Herring. The firmware node is the parent of the gpio node, so use of_get_parent() instead of a phandle. Changes in v4: * Move the gpio expander node under the firmware node; this requires an addtional patch that makes the firmware node into a bus * Rename the gpio node to just 'gpio' * Drop the platform driver .owner set Changes in v3: * Kconfig tweaks * Check rpi_exp_gpio_get_polarity() return value * Redundant header removal * Redundant platform_set_drvdata() call removal * Small coding style changes Changes in v2: * Driver renamed to gpio-raspberrypi-exp * Compatible string renamed to "raspberrypi,firmware-gpio" * Firmware error check * Smaller tweaks listed in individual patches Baruch Siach (4): ARM: bcm2835: sync firmware properties with downstream dt-bindings: gpio: add raspberry pi GPIO expander binding ARM: dts: bcm2835: make the firmware node into a bus ARM: dts: bcm2837-rpi-3-b: add GPIO expander Dave Stevenson (1): gpio: raspberrypi-exp: Driver for RPi3 GPIO expander via mailbox service .../bindings/gpio/raspberrypi,firmware-gpio.txt | 30 +++ arch/arm/boot/dts/bcm2835-rpi.dtsi | 4 +- arch/arm/boot/dts/bcm2837-rpi-3-b.dts | 17 ++ drivers/gpio/Kconfig | 9 + drivers/gpio/Makefile | 1 + drivers/gpio/gpio-raspberrypi-exp.c | 252 +++++++++++++++++++++ include/soc/bcm2835/raspberrypi-firmware.h | 18 ++ 7 files changed, 330 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/gpio/raspberrypi,firmware-gpio.txt create mode 100644 drivers/gpio/gpio-raspberrypi-exp.c -- 2.16.1 -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html