drivers: spi: Microchip XEC General Purpose SPI (GPSPI) controller

SPI driver for Microchip XEC family General Purpose SPI (GPSPI)
controller. GPSPI is a byte oriented controller with hardware
support of chip select assertion. The controller and driver also
supports GPIO control of SPI chip select based upon the device
tree configuration. The driver supports SPI asynchronous mode for
byte by byte transfers (no DMA at this time).

Signed-off-by: Manimaran A <manimaran.a@microchip.com>

drivers/spi/CMakeLists.txt

@@ -45,6 +45,8 @@ zephyr_library_sources_ifdef(CONFIG_SPI_AMBIQ		spi_ambiq.c)
 zephyr_library_sources_ifdef(CONFIG_SPI_RPI_PICO_PIO	spi_rpi_pico_pio.c)
 zephyr_library_sources_ifdef(CONFIG_MSPI_AMBIQ		mspi_ambiq.c)
 zephyr_library_sources_ifdef(CONFIG_SPI_MCHP_MSS	spi_mchp_mss.c)
+zephyr_library_sources_ifdef(CONFIG_SPI_XEC_GPSPI	spi_xec_gpspi.c)
+
 zephyr_library_sources_ifdef(CONFIG_SPI_RTIO spi_rtio.c)
 zephyr_library_sources_ifdef(CONFIG_SPI_ASYNC spi_signal.c)
 zephyr_library_sources_ifdef(CONFIG_USERSPACE		spi_handlers.c)

drivers/spi/Kconfig

@@ -142,5 +142,6 @@ source "drivers/spi/Kconfig.npcx"
 source "drivers/spi/Kconfig.mchp_mss"
 
 source "drivers/spi/Kconfig.grlib_spimctrl"
+source "drivers/spi/Kconfig.xec_gpspi"
 
 endif # SPI

drivers/spi/Kconfig.xec_gpspi

@@ -0,0 +1,25 @@
+# Microchip XEC GPSPI
+
+# Copyright (c) 2022 Microchip Technology Inc.
+# SPDX-License-Identifier: Apache-2.0
+
+config SPI_XEC_GPSPI
+	bool "Microchip MEC15x/MEC172x XEC GPSPI driver"
+	default y
+	depends on DT_HAS_MICROCHIP_XEC_GPSPI_ENABLED
+	help
+	  Enable support for Microchip MEC15xx/MEC172x XEC GPSPI driver.
+	  The GPSPI controller is a simple, byte-by-byte GPI controller
+	  using GPIO's as chip select.
+
+if SPI_XEC_GPSPI
+
+config SPI_XEC_GPSPI_DMA
+	bool "Microchip XEC GPSPI DMA Support"
+	select DMA
+	help
+	  Enable the SPI DMA mode for GPSPI instances
+	  that enable dma channels in their device tree node.
+	  Enables Microchip XEC DMA driver.
+
+endif # SPI_XEC_GPSPI