i2c: microchip: pci1xxxx: Add driver for I2C host controller in multifunction endpoint of pci1xxxx switch

Microchip pci1xxxx is an unmanaged PCIe3.1a Switch for Consumer,
Industrial and Automotive applications. This switch has multiple
downstream ports. In one of the Switch's Downstream port, there
is a multifunction endpoint for peripherals which includes an I2C
host controller. The I2C function in the endpoint operates at 100KHz,
400KHz and 1 MHz and has buffer depth of 128 bytes.
This patch provides the I2C controller driver for the I2C function
of the switch.

Signed-off-by: Tharun Kumar P <tharunkumar.pasumarthi@microchip.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Author: Tharun Kumar P

MAINTAINERS

@@ -13435,6 +13435,14 @@ F:	Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml
 F:	drivers/nvmem/microchip-otpc.c
 F:	include/dt-bindings/nvmem/microchip,sama7g5-otpc.h
 
+MICROCHIP PCI1XXXX I2C DRIVER
+M:	Tharun Kumar P <tharunkumar.pasumarthi@microchip.com>
+M:	Kumaravel Thiagarajan <kumaravel.thiagarajan@microchip.com>
+M:	Microchip Linux Driver Support <UNGLinuxDriver@microchip.com>
+L:	linux-i2c@vger.kernel.org
+S:	Maintained
+F:	drivers/i2c/busses/i2c-mchp-pci1xxxx.c
+
 MICROCHIP PWM DRIVER
 M:	Claudiu Beznea <claudiu.beznea@microchip.com>
 L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)

drivers/i2c/busses/Kconfig

@@ -1267,6 +1267,16 @@ config I2C_PARPORT
 	  This support is also available as a module.  If so, the module
 	  will be called i2c-parport.
 
+config I2C_PCI1XXXX
+	tristate "PCI1XXXX I2C Host Adapter"
+	depends on PCI
+	help
+	  If you say yes to this option, support will be included for
+	  Microchip PCI1XXXX's I2C interface.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called i2c-mchp-pci1xxxx.
+
 config I2C_ROBOTFUZZ_OSIF
 	tristate "RobotFuzz Open Source InterFace USB adapter"
 	depends on USB

drivers/i2c/busses/Makefile

@@ -133,6 +133,7 @@ obj-$(CONFIG_I2C_DIOLAN_U2C)	+= i2c-diolan-u2c.o
 obj-$(CONFIG_I2C_DLN2)		+= i2c-dln2.o
 obj-$(CONFIG_I2C_CP2615) += i2c-cp2615.o
 obj-$(CONFIG_I2C_PARPORT)	+= i2c-parport.o
+obj-$(CONFIG_I2C_PCI1XXXX)	+= i2c-mchp-pci1xxxx.o
 obj-$(CONFIG_I2C_ROBOTFUZZ_OSIF)	+= i2c-robotfuzz-osif.o
 obj-$(CONFIG_I2C_TAOS_EVM)	+= i2c-taos-evm.o
 obj-$(CONFIG_I2C_TINY_USB)	+= i2c-tiny-usb.o