/************************************************************************************ * configs/sam4l-xplained/src/sam_spi.c * * Copyright (C) 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. * ************************************************************************************/ /************************************************************************************ * Included Files ************************************************************************************/ #include #include #include #include #include #include "sam_gpio.h" #include "sam_spi.h" #include "sam4l-xplained.h" #ifdef CONFIG_SAM34_SPI0 /************************************************************************************ * Definitions ************************************************************************************/ /* Configuration ********************************************************************/ #if defined(CONFIG_SAM4L_XPLAINED_IOMODULE) && \ defined(CONFIG_SAM4L_XPLAINED_OLED1MODULE) && defined(CONFIG_SPI_OWNBUS) # error CONFIG_SPI_OWNBUS must not defined if using both I/O1 and OLED1 modules #endif /* Enables debug output from this file (needs CONFIG_DEBUG too) */ #undef SPI_DEBUG /* Define to enable debug */ #undef SPI_VERBOSE /* Define to enable verbose debug */ #ifdef SPI_DEBUG # define spidbg lldbg # ifdef SPI_VERBOSE # define spivdbg lldbg # else # define spivdbg(x...) # endif #else # undef SPI_VERBOSE # define spidbg(x...) # define spivdbg(x...) #endif /************************************************************************************ * Private Functions ************************************************************************************/ /************************************************************************************ * Public Functions ************************************************************************************/ /************************************************************************************ * Name: sam_spiinitialize * * Description: * Called to configure SPI chip select GPIO pins for the SAM3U10E-EVAL board. * ************************************************************************************/ void weak_function sam_spiinitialize(void) { /* The I/O module containing the SD connector may or may not be installed. And, if * it is installed, it may be in connector EXT1 or EXT2. */ #ifdef CONFIG_SAM4L_XPLAINED_IOMODULE /* TODO: enable interrupt on card detect */ sam_configgpio(GPIO_SD_CD); /* Card detect input */ sam_configgpio(GPIO_SD_CS); /* Chip select output */ #endif #ifdef CONFIG_SAM4L_XPLAINED_OLED1MODULE sam_configgpio(GPIO_OLED_DATA); /* Command/data */ sam_configgpio(GPIO_OLED_CS); /* Card detect input */ #endif } /**************************************************************************** * Name: sam_spi0select, sam_spi0status, and sam_spic0mddata * * Description: * These external functions must be provided by board-specific logic. They * include: * * o sam_spi0select is a functions tomanage the board-specific chip selects * o sam_spi0status and sam_spic0mddata: 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_spi0select() and sam_spi0status() 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_spic0mddata() 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). * ****************************************************************************/ /**************************************************************************** * Name: sam_spi0select * * 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: * devid - Identifies the (logical) device * selected - TRUE:Select the device, FALSE:De-select the device * * Returned Values: * None * ****************************************************************************/ void sam_spi0select(enum spi_dev_e devid, bool selected) { #ifdef CONFIG_SAM4L_XPLAINED_IOMODULE /* Select/de-select the SD card */ if (devid == SPIDEV_MMCSD) { /* Active low */ sam_gpiowrite(GPIO_SD_CS, !selected); } #ifdef CONFIG_SAM4L_XPLAINED_OLED1MODULE else #endif #endif #ifdef CONFIG_SAM4L_XPLAINED_OLED1MODULE /* Select/de-select the OLED */ if (devid == SPIDEV_DISPLAY) { /* Active low */ sam_gpiowrite(GPIO_OLED_CS, !selected); } #endif } /**************************************************************************** * Name: sam_spi0status * * Description: * Return status information associated with the SPI device. * * Input Parameters: * devid - Identifies the (logical) device * * Returned Values: * Bit-encoded SPI status (see include/nuttx/spi/spi.h. * ****************************************************************************/ uint8_t sam_spi0status(FAR struct spi_dev_s *dev, enum spi_dev_e devid) { uint8_t ret = 0; #ifdef CONFIG_SAM4L_XPLAINED_IOMODULE /* Check if an SD card is present in the microSD slot */ if (devid == SPIDEV_MMCSD) { /* Active low */ if (!sam_gpioread(GPIO_SD_CD)) { ret |= SPI_STATUS_PRESENT; } } #endif return ret; } #endif /* CONFIG_SAM34_SPI0 */ /**************************************************************************** * Name: sam_spic0mddata * * 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_spic0mddata(FAR struct spi_dev_s *dev, enum spi_dev_e devid, bool cmd) { #ifdef CONFIG_SAM4L_XPLAINED_OLED1MODULE if (devid == SPIDEV_DISPLAY) { /* This is the Data/Command control pad which determines whether the * data bits are data or a command. * * High: the inputs are treated as display data. * Low: the inputs are transferred to the command registers. */ (void)sam_gpiowrite(GPIO_OLED_DATA, !cmd); } #endif return OK; } #endif