spi: Add FSI-attached SPI controller driver

There exists a set of SPI controllers on some POWER processors that may be accessed through the FSI bus. Add a driver to traverse the FSI CFAM engine that can access and drive the SPI controllers. This driver would typically be used by a baseboard management controller (BMC). The SPI controllers operate by means of programming a sequencing engine which automatically manages the usual SPI protocol buses. The driver programs each transfer into the sequencer as various operations specifying the slave chip and shifting data in and out on the lines. Signed-off-by: Eddie James <eajames@linux.ibm.com> Link: https://lore.kernel.org/r/20200306194118.18581-3-eajames@linux.ibm.com Signed-off-by: Mark Brown <broonie@kernel.org>
mariux64 · Mar 10, 2020 · bbb6b2f · bbb6b2f
1 parent 1e7479d
commit bbb6b2f
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diff --git a/MAINTAINERS b/MAINTAINERS
@@ -6861,6 +6861,13 @@ S:	Maintained
 F:	drivers/i2c/busses/i2c-fsi.c
 F:	Documentation/devicetree/bindings/i2c/i2c-fsi.txt
 
+FSI-ATTACHED SPI DRIVER
+M:	Eddie James <eajames@linux.ibm.com>
+L:	linux-spi@vger.kernel.org
+S:	Maintained
+F:	drivers/spi/spi-fsi.c
+F:	Documentation/devicetree/bindings/fsi/ibm,fsi2spi.yaml
+
 FSNOTIFY: FILESYSTEM NOTIFICATION INFRASTRUCTURE
 M:	Jan Kara <jack@suse.cz>
 R:	Amir Goldstein <amir73il@gmail.com>

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
@@ -271,6 +271,13 @@ config SPI_FALCON
 	  has only been tested with m25p80 type chips. The hardware has no
 	  support for other types of SPI peripherals.
 
+config SPI_FSI
+	tristate "FSI SPI driver"
+	depends on FSI
+	help
+	  This enables support for the driver for FSI bus attached SPI
+	  controllers.
+
 config SPI_FSL_LPSPI
 	tristate "Freescale i.MX LPSPI controller"
 	depends on ARCH_MXC || COMPILE_TEST

diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
@@ -42,6 +42,7 @@ spi-dw-midpci-objs			:= spi-dw-pci.o spi-dw-mid.o
 obj-$(CONFIG_SPI_EFM32)			+= spi-efm32.o
 obj-$(CONFIG_SPI_EP93XX)		+= spi-ep93xx.o
 obj-$(CONFIG_SPI_FALCON)		+= spi-falcon.o
+obj-$(CONFIG_SPI_FSI)			+= spi-fsi.o
 obj-$(CONFIG_SPI_FSL_CPM)		+= spi-fsl-cpm.o
 obj-$(CONFIG_SPI_FSL_DSPI)		+= spi-fsl-dspi.o
 obj-$(CONFIG_SPI_FSL_LIB)		+= spi-fsl-lib.o