/************************************************************************************
* configs/sam3u-ek/src/up_spi.c
* arch/arm/src/board/up_spi.c
*
* Copyright (C) 2009, 2011 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 <stdint.h>
#include <stdbool.h>
#include <debug.h>
#include <errno.h>
#include <nuttx/spi.h>
#include <arch/board/board.h>
#include "up_arch.h"
#include "chip.h"
#include "sam3u_internal.h"
#include "sam3uek_internal.h"
#ifdef CONFIG_SAM3U_SPI
/************************************************************************************
* Definitions
************************************************************************************/
/* 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: sam3u_spiinitialize
*
* Description:
* Called to configure SPI chip select GPIO pins for the SAM3U10E-EVAL board.
*
************************************************************************************/
void weak_function sam3u_spiinitialize(void)
{
/* The ZigBee module connects used NPCS0. However, there is not yet any
* ZigBee support.
*/
/* The touchscreen connects using NPCS2 (PC14). */
#if defined(CONFIG_INPUT) && defined(CONFIG_INPUT_ADS7843E)
sam3u_configgpio(GPIO_TSC_NPCS2);
#endif
}
/****************************************************************************
* Name: sam3u_spicsnumber, sam3u_spiselect, sam3u_spistatus, and
* sam3u_spicmddata
*
* Description:
* These external functions must be provided by board-specific logic. They
* include:
*
* o sam3u_spicsnumbe and sam3u_spiselect which are helper functions to
* manage the board-specific aspects of the unique SAM3U chip select
* architecture.
* o sam3u_spistatus and sam3u_spicmddata: Implementations of the status
* and cmddata methods of the SPI interface defined by struct spi_ops_
* (see include/nuttx/spi.h). All other methods including
* up_spiinitialize()) are provided by common SAM3U logic.
*
* To use this common SPI logic on your board:
*
* 1. Provide logic in sam3u_boardinitialize() to configure SPI chip select
* pins.
* 2. Provide sam3u_spicsnumber(), sam3u_spiselect() and sam3u_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
* sam3u_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: sam3u_spicsnumber
*
* Description:
* The SAM3U has 4 CS registers for controlling device features. This
* function must be provided by board-specific code. Given a logical device
* ID, this function returns a number from 0 to 3 that identifies one of
* these SAM3U CS resources.
*
* Input Parameters:
* devid - Identifies the (logical) device
*
* Returned Values:
* On success, a CS number from 0 to 3 is returned; A negated errno may
* be returned on a failure.
*
****************************************************************************/
int sam3u_spicsnumber(enum spi_dev_e devid)
{
int cs = -EINVAL;
#if defined(CONFIG_INPUT) && defined(CONFIG_INPUT_ADS7843E)
if (devid == SPIDEV_TOUCHSCREEN)
{
/* Assert the CS pin to the OLED display */
cs = 2;
}
#endif
spidbg("devid: %d CS: %d\n", (int)devid, cs);
return cs;
}
/****************************************************************************
* Name: sam3u_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 sam3u_spiselect(enum spi_dev_e devid, bool selected)
{
/* The touchscreen chip select is implemented as a GPIO OUTPUT that must
* be controlled by this function. This is because the ADS7843E driver
* must be able to sample the device BUSY GPIO input between SPI transfers.
* However, the AD7843E will tri-state the BUSY input whenever the chip
* select is de-asserted. So the only option is to control the chip select
* manually and hold it low throughout the SPI transfer.
*/
#if defined(CONFIG_INPUT) && defined(CONFIG_INPUT_ADS7843E)
if (devid == SPIDEV_TOUCHSCREEN)
{
sam3u_gpiowrite(GPIO_TSC_NPCS2, !selected);
}
#endif
}
/****************************************************************************
* Name: sam3u_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.h.
*
****************************************************************************/
uint8_t sam3u_spistatus(FAR struct spi_dev_s *dev, enum spi_dev_e devid)
{
return 0;
}
#endif /* CONFIG_SAM3U_SPI */
