/************************************************************************************
* configs/shenzhou/src/up_touchscreen.c
* arch/arm/src/board/up_touchscreen.c
*
* Copyright (C) 2011-2012 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 <stdio.h>
#include <debug.h>
#include <assert.h>
#include <errno.h>
#include <nuttx/irq.h>
#include <nuttx/spi/spi.h>
#include <nuttx/input/touchscreen.h>
#include <nuttx/input/ads7843e.h>
#include "stm32.h"
#include "shenzhou-internal.h"
/****************************************************************************
* Pre-Processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
#ifdef CONFIG_INPUT_ADS7843E
#ifndef CONFIG_INPUT
# error "Touchscreen support requires CONFIG_INPUT"
#endif
#ifndef CONFIG_STM32_SPI3
# error "Touchscreen support requires CONFIG_STM32_SPI3"
#endif
#ifndef CONFIG_ADS7843E_FREQUENCY
# define CONFIG_ADS7843E_FREQUENCY 500000
#endif
#ifndef CONFIG_ADS7843E_SPIDEV
# define CONFIG_ADS7843E_SPIDEV 3
#endif
#if CONFIG_ADS7843E_SPIDEV != 3
# error "CONFIG_ADS7843E_SPIDEV must be three"
#endif
#ifndef CONFIG_ADS7843E_DEVMINOR
# define CONFIG_ADS7843E_DEVMINOR 0
#endif
/****************************************************************************
* Private Types
****************************************************************************/
struct stm32_config_s
{
struct ads7843e_config_s dev;
xcpt_t handler;
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* IRQ/GPIO access callbacks. These operations all hidden behind
* callbacks to isolate the ADS7843E driver from differences in GPIO
* interrupt handling by varying boards and MCUs. If possible,
* interrupts should be configured on both rising and falling edges
* so that contact and loss-of-contact events can be detected.
*
* attach - Attach the ADS7843E interrupt handler to the GPIO interrupt
* enable - Enable or disable the GPIO interrupt
* clear - Acknowledge/clear any pending GPIO interrupt
* pendown - Return the state of the pen down GPIO input
*/
static int tsc_attach(FAR struct ads7843e_config_s *state, xcpt_t isr);
static void tsc_enable(FAR struct ads7843e_config_s *state, bool enable);
static void tsc_clear(FAR struct ads7843e_config_s *state);
static bool tsc_busy(FAR struct ads7843e_config_s *state);
static bool tsc_pendown(FAR struct ads7843e_config_s *state);
/****************************************************************************
* Private Data
****************************************************************************/
/* A reference to a structure of this type must be passed to the ADS7843E
* driver. This structure provides information about the configuration
* of the ADS7843E and provides some board-specific hooks.
*
* Memory for this structure is provided by the caller. It is not copied
* by the driver and is presumed to persist while the driver is active. The
* memory must be writable because, under certain circumstances, the driver
* may modify frequency or X plate resistance values.
*/
static struct stm32_config_s g_tscinfo =
{
{
.frequency = CONFIG_ADS7843E_FREQUENCY,
.attach = tsc_attach,
.enable = tsc_enable,
.clear = tsc_clear,
.busy = tsc_busy,
.pendown = tsc_pendown,
},
.handler = NULL,
};
/****************************************************************************
* Private Functions
****************************************************************************/
/* IRQ/GPIO access callbacks. These operations all hidden behind
* callbacks to isolate the ADS7843E driver from differences in GPIO
* interrupt handling by varying boards and MCUs. If possible,
* interrupts should be configured on both rising and falling edges
* so that contact and loss-of-contact events can be detected.
*
* attach - Attach the ADS7843E interrupt handler to the GPIO interrupt
* enable - Enable or disable the GPIO interrupt
* clear - Acknowledge/clear any pending GPIO interrupt
* pendown - Return the state of the pen down GPIO input
*/
static int tsc_attach(FAR struct ads7843e_config_s *state, xcpt_t handler)
{
FAR struct stm32_config_s *priv = (FAR struct stm32_config_s *)state;
/* Just save the handler for use when the interrupt is enabled */
priv->handler = handler;
return OK;
}
static void tsc_enable(FAR struct ads7843e_config_s *state, bool enable)
{
FAR struct stm32_config_s *priv = (FAR struct stm32_config_s *)state;
/* The caller should not attempt to enable interrupts if the handler
* has not yet been 'attached'
*/
DEBUGASSERT(priv->handler || !enable);
/* Attach and enable, or detach and disable */
ivdbg("enable:%d\n", enable);
if (enable)
{
(void)stm32_gpiosetevent(GPIO_TP_INT, true, true, false,
priv->handler);
}
else
{
(void)stm32_gpiosetevent(GPIO_TP_INT, false, false, false, NULL);
}
}
static void tsc_clear(FAR struct ads7843e_config_s *state)
{
/* Does nothing */
}
static bool tsc_busy(FAR struct ads7843e_config_s *state)
{
/* Hmmm... The ADS7843E BUSY pin is not brought out on the Shenzhou board.
* We will most certainly have to revisit this. There is this cryptic
* statement in the XPT2046 spec: "No DCLK delay required with dedicated
* serial port."
*
* The busy state is used by the ADS7843E driver to control the delay
* between sending the command, then reading the returned data.
*/
return false;
}
static bool tsc_pendown(FAR struct ads7843e_config_s *state)
{
/* XPT2046 uses an an internal pullup resistor. The PENIRQ output goes low
* due to the current path through the touch screen to ground, which
* initiates an interrupt to the processor via TP_INT.
*/
bool pendown = !stm32_gpioread(GPIO_TP_INT);
ivdbg("pendown:%d\n", pendown);
return pendown;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: arch_tcinitialize
*
* Description:
* Each board that supports a touchscreen device must provide this function.
* This function is called by application-specific, setup logic to
* configure the touchscreen device. This function will register the driver
* as /dev/inputN where N is the minor device number.
*
* Input Parameters:
* minor - The input device minor number
*
* Returned Value:
* Zero is returned on success. Otherwise, a negated errno value is
* returned to indicate the nature of the failure.
*
****************************************************************************/
int arch_tcinitialize(int minor)
{
FAR struct spi_dev_s *dev;
int ret;
idbg("minor %d\n", minor);
DEBUGASSERT(minor == 0);
/* Configure and enable the ADS7843E interrupt pin as an input. */
(void)stm32_configgpio(GPIO_TP_INT);
/* Get an instance of the SPI interface */
dev = up_spiinitialize(CONFIG_ADS7843E_SPIDEV);
if (!dev)
{
idbg("Failed to initialize SPI bus %d\n", CONFIG_ADS7843E_SPIDEV);
return -ENODEV;
}
/* Initialize and register the SPI touschscreen device */
ret = ads7843e_register(dev, &g_tscinfo.dev, CONFIG_ADS7843E_DEVMINOR);
if (ret < 0)
{
idbg("Failed to initialize SPI bus %d\n", CONFIG_ADS7843E_SPIDEV);
/* up_spiuninitialize(dev); */
return -ENODEV;
}
return OK;
}
/****************************************************************************
* Name: arch_tcuninitialize
*
* Description:
* Each board that supports a touchscreen device must provide this function.
* This function is called by application-specific, setup logic to
* uninitialize the touchscreen device.
*
* Input Parameters:
* None
*
* Returned Value:
* None.
*
****************************************************************************/
void arch_tcuninitialize(void)
{
/* No support for un-initializing the touchscreen ADS7843E device yet */
}
#endif /* CONFIG_INPUT_ADS7843E */