px4-firmware/nuttx/drivers/input/ads7843e.h

172 lines
6.9 KiB
C

/********************************************************************************************
* drivers/input/ads7843e.h
*
* Copyright (C) 2011-2012 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* References:
* "Touch Screen Controller, ADS7843," Burr-Brown Products from Texas
* Instruments, SBAS090B, September 2000, Revised May 2002"
*
* 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 __DRIVERS_INPUT_ADS7843E_H
#define __DRIVERS_INPUT_ADS7843E_H
/********************************************************************************************
* Included Files
********************************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <semaphore.h>
#include <poll.h>
#include <wdog.h>
#include <nuttx/wqueue.h>
#include <nuttx/spi.h>
#include <nuttx/clock.h>
#include <nuttx/input/ads7843e.h>
/********************************************************************************************
* Pre-Processor Definitions
********************************************************************************************/
/* Configuration ****************************************************************************/
/* Reference counting is partially implemented, but not needed in the current design. */
#undef CONFIG_ADS7843E_REFCNT
/* ADS7843E Interfaces *********************************************************************/
/* ADS7843E command bit settings */
#define ADS7843E_CMD_PD0 (1 << 0) /* PD0 */
#define ADS7843E_CMD_PD1 (1 << 1) /* PD1 */
#define ADS7843E_CMD_DFR (1 << 2) /* SER/DFR */
#define ADS7843E_CMD_EIGHT_BITS_MOD (1 << 3) /* Mode */
#define ADS7843E_CMD_START (1 << 7) /* Start Bit */
#define ADS7843E_CMD_SWITCH_SHIFT 4 /* Address setting */
/* ADS7843E Commands */
#define ADS7843_CMD_YPOSITION \
((1 << ADS7843E_CMD_SWITCH_SHIFT)|ADS7843E_CMD_START|ADS7843E_CMD_PD0|ADS7843E_CMD_PD1)
#define ADS7843_CMD_XPOSITION \
((5 << ADS7843E_CMD_SWITCH_SHIFT)|ADS7843E_CMD_START|ADS7843E_CMD_PD0|ADS7843E_CMD_PD1)
#define ADS7843_CMD_ENABPINIRQ \
((1 << ADS7843E_CMD_SWITCH_SHIFT)|ADS7843E_CMD_START)
/* Driver support **************************************************************************/
/* This format is used to construct the /dev/input[n] device driver path. It
* defined here so that it will be used consistently in all places.
*/
#define DEV_FORMAT "/dev/input%d"
#define DEV_NAMELEN 16
/* Poll the pen position while the pen is down at this rate (50MS): */
#define ADS7843E_WDOG_DELAY ((50 + (MSEC_PER_TICK-1))/ MSEC_PER_TICK)
/********************************************************************************************
* Public Types
********************************************************************************************/
/* This describes the state of one contact */
enum ads7843e_contact_3
{
CONTACT_NONE = 0, /* No contact */
CONTACT_DOWN, /* First contact */
CONTACT_MOVE, /* Same contact, possibly different position */
CONTACT_UP, /* Contact lost */
};
/* This structure describes the results of one ADS7843E sample */
struct ads7843e_sample_s
{
uint8_t id; /* Sampled touch point ID */
uint8_t contact; /* Contact state (see enum ads7843e_contact_e) */
bool valid; /* True: x,y contain valid, sampled data */
uint16_t x; /* Measured X position */
uint16_t y; /* Measured Y position */
};
/* This structure describes the state of one ADS7843E driver instance */
struct ads7843e_dev_s
{
#ifdef CONFIG_ADS7843E_MULTIPLE
FAR struct ads7843e_dev_s *flink; /* Supports a singly linked list of drivers */
#endif
#ifdef CONFIG_ADS7843E_REFCNT
uint8_t crefs; /* Number of times the device has been opened */
#endif
uint8_t nwaiters; /* Number of threads waiting for ADS7843E data */
uint8_t id; /* Current touch point ID */
volatile bool penchange; /* An unreported event is buffered */
sem_t devsem; /* Manages exclusive access to this structure */
sem_t waitsem; /* Used to wait for the availability of data */
FAR struct ads7843e_config_s *config; /* Board configuration data */
FAR struct spi_dev_s *spi; /* Saved SPI driver instance */
struct work_s work; /* Supports the interrupt handling "bottom half" */
struct ads7843e_sample_s sample; /* Last sampled touch point data */
WDOG_ID wdog; /* Poll the position while the pen is down */
/* The following is a list if poll structures of threads waiting for
* driver events. The 'struct pollfd' reference for each open is also
* retained in the f_priv field of the 'struct file'.
*/
#ifndef CONFIG_DISABLE_POLL
struct pollfd *fds[CONFIG_ADS7843E_NPOLLWAITERS];
#endif
};
/********************************************************************************************
* Public Function Prototypes
********************************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C" {
#else
#define EXTERN extern
#endif
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* __DRIVERS_INPUT_ADS7843E_H */