/************************************************************************************
* configs/sam4l-xplained/src/sam_spi.c
*
* Copyright (C) 2013 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 <nuttx/config.h>
#include <stdbool.h>
#include <debug.h>
#include <errno.h>
#include <nuttx/spi/spi.h>
#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_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).
*
****************************************************************************/
/****************************************************************************
* 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:
* 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)
{
#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_spistatus
*
* 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_spistatus(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_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)
{
#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
