1 files changed, 77 insertions, 0 deletions
diff --git a/bsps/arm/raspberrypi/include/bsp/spi.h b/bsps/arm/raspberrypi/include/bsp/spi.h
new file mode 100644
index 0000000000..1bbbc6d2a4
--- /dev/null
+++ b/bsps/arm/raspberrypi/include/bsp/spi.h
@@ -0,0 +1,77 @@
+/**
+ * @file spi.h
+ *
+ * @ingroup raspberrypi_spi
+ *
+ * @brief Raspberry Pi specific SPI definitions.
+ */
+
+/*
+ *  Copyright (c) 2014-2015 Andre Marques <andre.lousa.marques at gmail.com>
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.org/license/LICENSE.
+ */
+
+#ifndef LIBBSP_ARM_RASPBERRYPI_SPI_H
+#define LIBBSP_ARM_RASPBERRYPI_SPI_H
+
+#include <rtems/libi2c.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/**
+ * @name SPI constants.
+ *
+ * @{
+ */
+
+/**
+ * @brief GPU processor core clock rate in Hz.
+ *
+ * Unless configured otherwise on a "config.txt" file present on the SD card
+ * the GPU defaults to 250 MHz. Currently only 250 MHz is supported.
+ */
+
+/* TODO: It would be nice if this value could be probed at startup, probably
+ *       using the Mailbox interface since the usual way of setting this on
+ *       the hardware is through a "config.txt" text file on the SD card.
+ *       Having this setup on the configure.ac script would require changing
+ *       the same setting on two different places. */
+#define GPU_CORE_CLOCK_RATE 250000000
+
+/** @} */
+
+/**
+ * @name SPI directives.
+ *
+ * @{
+ */
+
+/**
+ * @brief Setups the Raspberry Pi SPI bus (located on the GPIO header)
+ *        on the "/dev/spi" device file, and registers the bus on the
+ *        libi2c API.
+ *
+ * @param[in] bidirectional_mode If TRUE sets the SPI bus to use 2-wire SPI,
+ *                               where the MOSI data line doubles as the
+ *                               slave out (SO) and slave in (SI) data lines.
+ *                               If FALSE the bus defaults to the usual
+ *                               3-wire SPI, with 2 separate data lines
+ *                               (MOSI and MISO).
+ *
+ * @retval Returns libi2c bus number.
+ * @retval <0 Could not register the bus. See @see rtems_libi2c_register_bus().
+ */
+extern int rpi_spi_init(bool bidirectional_mode);
+
+/** @} */
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* LIBBSP_ARM_RASPBERRYPI_SPI_H */