ramips: add AW9523 I2C GPIO expander driver

This adds a driver for the AW9523 I2C GPIO expander.

This driver is required to make LEDs as well as buttons on the Tenbay
T-MB5EU-V01 work.

This driver already had several upstream iterations. I'm working to
push this driver to mainline.

Ref: https://patchwork.ozlabs.org/project/linux-gpio/list/?series=226287

Signed-off-by: David Bauer <mail@david-bauer.net>

1 files changed, 72 insertions, 0 deletions

diff --git a/target/linux/ramips/patches-5.4/805-pinctrl-AW9523.patch b/target/linux/ramips/patches-5.4/805-pinctrl-AW9523.patch
new file mode 100644
index 0000000000..d8e17a671a
--- /dev/null
+++ b/target/linux/ramips/patches-5.4/805-pinctrl-AW9523.patch
@@ -0,0 +1,72 @@
+From: AngeloGioacchino Del Regno
+        <angelogioacchino.delregno@somainline.org>
+To: linus.walleij@linaro.org
+Cc: linux-kernel@vger.kernel.org, konrad.dybcio@somainline.org,
+        marijn.suijten@somainline.org, martin.botka@somainline.org,
+        phone-devel@vger.kernel.org, linux-gpio@vger.kernel.org,
+        devicetree@vger.kernel.org, robh+dt@kernel.org,
+        AngeloGioacchino Del Regno
+        <angelogioacchino.delregno@somainline.org>
+Subject: [PATCH v5 1/2] pinctrl: Add driver for Awinic AW9523/B I2C GPIO
+ Expander
+Date: Mon, 25 Jan 2021 19:22:18 +0100
+
+The Awinic AW9523(B) is a multi-function I2C gpio expander in a
+TQFN-24L package, featuring PWM (max 37mA per pin, or total max
+power 3.2Watts) for LED driving capability.
+
+It has two ports with 8 pins per port (for a total of 16 pins),
+configurable as either PWM with 1/256 stepping or GPIO input/output,
+1.8V logic input; each GPIO can be configured as input or output
+independently from each other.
+
+This IC also has an internal interrupt controller, which is capable
+of generating an interrupt for each GPIO, depending on the
+configuration, and will raise an interrupt on the INTN pin to
+advertise this to an external interrupt controller.
+
+Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
+---
+ drivers/pinctrl/Kconfig          |   17 +
+ drivers/pinctrl/Makefile         |    1 +
+ drivers/pinctrl/pinctrl-aw9523.c | 1122 ++++++++++++++++++++++++++++++
+ 3 files changed, 1140 insertions(+)
+ create mode 100644 drivers/pinctrl/pinctrl-aw9523.c
+
+--- a/drivers/pinctrl/Kconfig
++++ b/drivers/pinctrl/Kconfig
+@@ -109,6 +109,24 @@ config PINCTRL_AMD
+ 	  Requires ACPI/FDT device enumeration code to set up a platform
+ 	  device.
+ 
++config PINCTRL_AW9523
++	bool "Awinic AW9523/AW9523B I2C GPIO expander pinctrl driver"
++	depends on OF && I2C
++	select PINMUX
++	select PINCONF
++	select GENERIC_PINCONF
++	select GPIOLIB
++	select GPIOLIB_IRQCHIP
++	select REGMAP
++	select REGMAP_I2C
++	help
++	  The Awinic AW9523/AW9523B is a multi-function I2C GPIO
++	  expander with PWM functionality. This driver bundles a
++	  pinctrl driver to select the function muxing and a GPIO
++	  driver to handle GPIO, when the GPIO function is selected.
++
++	  Say yes to enable pinctrl and GPIO support for the AW9523(B).
++
+ config PINCTRL_BM1880
+ 	bool "Bitmain BM1880 Pinctrl driver"
+ 	depends on OF && (ARCH_BITMAIN || COMPILE_TEST)
+--- a/drivers/pinctrl/Makefile
++++ b/drivers/pinctrl/Makefile
+@@ -14,6 +14,7 @@ obj-$(CONFIG_PINCTRL_AXP209)	+= pinctrl-
+ obj-$(CONFIG_PINCTRL_AT91)	+= pinctrl-at91.o
+ obj-$(CONFIG_PINCTRL_AT91PIO4)	+= pinctrl-at91-pio4.o
+ obj-$(CONFIG_PINCTRL_AMD)	+= pinctrl-amd.o
++obj-$(CONFIG_PINCTRL_AW9523)	+= pinctrl-aw9523.o
+ obj-$(CONFIG_PINCTRL_BM1880)	+= pinctrl-bm1880.o
+ obj-$(CONFIG_PINCTRL_DA850_PUPD) += pinctrl-da850-pupd.o
+ obj-$(CONFIG_PINCTRL_DIGICOLOR)	+= pinctrl-digicolor.o