/************************************************************************************ * arch/arm/src/sam34/sam_spi.h * * Copyright (C) 2009-2011, 2013 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * 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 __ARCH_ARM_SRC_SAM34_SAM_SPI_H #define __ARCH_ARM_SRC_SAM34_SAM_SPI_H /************************************************************************************ * Included Files ************************************************************************************/ #include #include #include #include "chip.h" /************************************************************************************ * Definitions ************************************************************************************/ /************************************************************************************ * Public Types ************************************************************************************/ /************************************************************************************ * Inline Functions ************************************************************************************/ #ifndef __ASSEMBLY__ /************************************************************************************ * Public Data ************************************************************************************/ #undef EXTERN #if defined(__cplusplus) #define EXTERN extern "C" extern "C" { #else #define EXTERN extern #endif /************************************************************************************ * Public Function Prototypes ************************************************************************************/ /**************************************************************************** * Name: sam_spiselect, sam_spistatus, and sam_spicmddata * * Description: * These external functions must be provided by board-specific logic. They * include: * * o sam_spiselect is a functions tomanage the board-specific chip selects * o sam_spistatus and sam_spicmddata: Implementations of the status * and cmddata methods of the SPI interface defined by struct spi_ops_ * (see include/nuttx/spi/spi.h). All other methods including * up_spiinitialize()) are provided by common SAM3/4 logic. * * To use this common SPI logic on your board: * * 1. Provide logic in sam_boardinitialize() to configure SPI chip select * pins. * 2. Provide sam_spiselect() and sam_spistatus() functions in your board- * specific logic. These functions will perform chip selection and * status operations using GPIOs in the way your board is configured. * 2. If CONFIG_SPI_CMDDATA is defined in the NuttX configuration, provide * sam_spicmddata() functions in your board-specific logic. This * function will perform cmd/data selection operations using GPIOs in * the way your board is configured. * 3. Add a call to up_spiinitialize() in your low level application * initialization logic * 4. The handle returned by up_spiinitialize() may then be used to bind the * SPI driver to higher level logic (e.g., calling * mmcsd_spislotinitialize(), for example, will bind the SPI driver to * the SPI MMC/SD driver). * ****************************************************************************/ #ifdef CONFIG_SAM34_SPI0 struct spi_dev_s; enum spi_dev_e; /**************************************************************************** * Name: sam_spiselect * * Description: * PIO chip select pins may be programmed by the board specific logic in * one of two different ways. First, the pins may be programmed as SPI * peripherals. In that case, the pins are completely controlled by the * SPI driver. This method still needs to be provided, but it may be only * a stub. * * An alternative way to program the PIO chip select pins is as a normal * GPIO output. In that case, the automatic control of the CS pins is * bypassed and this function must provide control of the chip select. * NOTE: In this case, the GPIO output pin does *not* have to be the * same as the NPCS pin normal associated with the chip select number. * * Input Parameters: * dev - SPI device info * devid - Identifies the (logical) device * selected - TRUE:Select the device, FALSE:De-select the device * * Returned Values: * None * ****************************************************************************/ void sam_spiselect(enum spi_dev_e devid, bool selected); /**************************************************************************** * Name: sam_spistatus * * Description: * Return status information associated with the SPI device. * * Input Parameters: * dev - SPI device info * devid - Identifies the (logical) device * * Returned Values: * Bit-encoded SPI status (see include/nuttx/spi/spi.h. * ****************************************************************************/ uint8_t sam_spistatus(FAR struct spi_dev_s *dev, enum spi_dev_e devid); /**************************************************************************** * Name: sam_spicmddata * * Description: * Some SPI devices require an additional control to determine if the SPI * data being sent is a command or is data. If CONFIG_SPI_CMDDATA then * this function will be called to different be command and data transfers. * * This is often needed, for example, by LCD drivers. Some LCD hardware * may be configured to use 9-bit data transfers with the 9th bit * indicating command or data. That same hardware may be configurable, * instead, to use 8-bit data but to require an additional, board- * specific GPIO control to distinguish command and data. This function * would be needed in that latter case. * * Input Parameters: * dev - SPI device info * devid - Identifies the (logical) device * * Returned Values: * Zero on success; a negated errno on failure. * ****************************************************************************/ #ifdef CONFIG_SPI_CMDDATA int sam_spicmddata(FAR struct spi_dev_s *dev, enum spi_dev_e devid, bool cmd); #endif #endif /* CONFIG_SAM34_SPI0 */ #undef EXTERN #if defined(__cplusplus) } #endif #endif /* __ASSEMBLY__ */ #endif /* __ARCH_ARM_SRC_SAM34_SAM_SPI_H */