bsps/imx*: Add an i.MX* specific GPIO SPI driver

This driver uses the generic spi-gpio driver to implement one based on
the i.MX* GPIO API.

bsps/arm/include/dev/spi/imx-spi-gpio.h

@@ -0,0 +1,88 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+
+/**
+ * @file
+ *
+ * @ingroup RTEMSDeviceIMXSPIGPIO
+ *
+ * @brief This header file provides the interfaces of
+ *   @ref RTEMSDeviceIMXSPIGPIO.
+ */
+
+/*
+ * Copyright (C) 2024 embedded brains GmbH & Co. KG
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _RTEMS_DEV_SPI_IMX_SPI_GPIO_H
+#define _RTEMS_DEV_SPI_IMX_SPI_GPIO_H
+
+#include <rtems.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/**
+ * @defgroup RTEMSDeviceIMXSPIGPIO
+ *
+ * @ingroup RTEMSDeviceSPIGPIO
+ *
+ * @brief A SPI bus driver that uses the i.MX/i.MXRT GPIO pins
+ *
+ * @{
+ */
+
+/**
+ * @brief Register all compatible nodes from the device tree.
+ *
+ * Search nodes in the device tree that are compatible to 'spi-gpio' and try to
+ * register the driver for them. Expects a node that looks (for example) like
+ * the following:
+ *
+ * ```
+ * gpiospi: spi {
+ * 	status = "okay";
+ * 	compatible = "spi-gpio";
+ * 	#address-cells = <0x1>;
+ * 	#size-cells = <0x0>;
+ * 
+ * 	sck-gpios = <&gpio2 27 0>;
+ * 	miso-gpios = <&gpio2 25 0>;
+ * 	mosi-gpios = <&gpio4 14 0>;
+ * 	cs-gpios = <&gpio4 10 1>;
+ * 	num-chipselects = <1>;
+ * 
+ * 	rtems,path = "/dev/gpiospi";
+ * };
+ * ```
+ */
+rtems_status_code imx_spi_gpio_init(void);
+
+/** @} */
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* _RTEMS_DEV_SPI_IMX_SPI_GPIO_H */