drivers: sdhc: add SD SPI mode host controller driver

Add SDHC driver implementing spi mode support for SD cards. This driver
implements the standard SD host controller APIs, and sets the host
property "is_spi" to indicate to the SD subsystem the card will be
running in SPI mode.

Signed-off-by: Daniel DeGrasse <[email protected]>

Author: danieldegrasse

drivers/sdhc/CMakeLists.txt

@@ -1,7 +1,8 @@
-# Copyright (c) 2022 NXP
+# Copyright 2022 NXP
 # SPDX-License-Identifier: Apache-2.0
 if (CONFIG_SDHC)
 
 zephyr_library()
 zephyr_library_sources_ifdef(CONFIG_IMX_USDHC imx_usdhc.c)
+zephyr_library_sources_ifdef(CONFIG_SPI_SDHC sdhc_spi.c)
 endif()

drivers/sdhc/Kconfig

@@ -9,6 +9,7 @@ menuconfig SDHC
 if SDHC
 
 source "drivers/sdhc/Kconfig.imx"
+source "drivers/sdhc/Kconfig.spi"
 
 config SDHC_INIT_PRIORITY
 	int "SDHC driver init priority"

drivers/sdhc/Kconfig.spi

@@ -0,0 +1,12 @@
+# Copyright (c) 2022, NXP
+# SPDX -License-Identifier: Apache-2.0
+
+DT_COMPAT_ZEPHYR_MMC_SPI_SLOT := zephyr,sdhc-spi-slot
+
+config SPI_SDHC
+	bool "SD protocol over SPI bus"
+	select SPI
+	select SDHC_SUPPORTS_SPI_MODE
+	default $(dt_compat_enabled,$(DT_COMPAT_ZEPHYR_MMC_SPI_SLOT))
+	help
+	  Enable the SPI SD host controller driver