/************************************************************************************ * configs/open1788/src/lpc17_touchscreen.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 #include #include #include #include #include #include "lpc17_gpio.h" #include "lpc17_ssp.h" #include "open1788.h" #ifdef CONFIG_INPUT_ADS7843E /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* Configuration ************************************************************/ #ifndef CONFIG_INPUT # error "Touchscreen support requires CONFIG_INPUT" #endif #ifndef CONFIG_LPC17_SSP1 # error "Touchscreen support requires CONFIG_LPC17_SSP1" #endif #ifndef CONFIG_LPC17_GPIOIRQ # error "Touchscreen support requires CONFIG_LPC17_GPIOIRQ" #endif #ifndef CONFIG_ADS7843E_FREQUENCY # define CONFIG_ADS7843E_FREQUENCY 500000 #endif #ifndef CONFIG_ADS7843E_SPIDEV # define CONFIG_ADS7843E_SPIDEV 1 #endif #if CONFIG_ADS7843E_SPIDEV != 1 # error "CONFIG_ADS7843E_SPIDEV must be one" #endif #ifndef CONFIG_ADS7843E_DEVMINOR # define CONFIG_ADS7843E_DEVMINOR 0 #endif /* REVISIT: Currently, XPT2046 reports BUSY all of the time. This is * probably GPIO setting issues. But there is this cryptic statement in * the XPT2046 spec: "No DCLK delay required with dedicated serial port." * * The busy state is used by the XPT2046 driver to control the delay * between sending the command, then reading the returned data. */ #define XPT2046_NO_BUSY 1 /**************************************************************************** * Private Types ****************************************************************************/ /**************************************************************************** * Private Function Prototypes ****************************************************************************/ /* IRQ/GPIO access callbacks. These operations all hidden behind * callbacks to isolate the XPT2046 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 XPT2046 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 XPT2046 * driver. This structure provides information about the configuration * of the XPT2046 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. */ static struct ads7843e_config_s g_tscinfo = { .frequency = CONFIG_ADS7843E_FREQUENCY, .attach = tsc_attach, .enable = tsc_enable, .clear = tsc_clear, .busy = tsc_busy, .pendown = tsc_pendown, }; /**************************************************************************** * Private Functions ****************************************************************************/ /* IRQ/GPIO access callbacks. These operations all hidden behind * callbacks to isolate the XPT2046 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 XPT2046 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) { /* Attach then enable the touchscreen interrupt handler */ (void)irq_attach(LPC17_IRQ_PENIRQ, handler, NULL); return OK; } static void tsc_enable(FAR struct ads7843e_config_s *state, bool enable) { iinfo("enable:%d\n", enable); if (enable) { /* Enable PENIRQ interrupts. NOTE: The pin interrupt is enabled from worker thread * logic after completion of processing of the touchscreen interrupt. */ up_enable_irq(LPC17_IRQ_PENIRQ); } else { /* Disable PENIRQ interrupts. NOTE: The PENIRQ interrupt will be disabled from * interrupt handling logic. */ up_disable_irq(LPC17_IRQ_PENIRQ); } } static void tsc_clear(FAR struct ads7843e_config_s *state) { /* Does nothing. The interrupt is cleared automatically in the GPIO * logic for the LPC17xx family. */ } static bool tsc_busy(FAR struct ads7843e_config_s *state) { /* The busy state is used by the XPT2046 driver to control the delay * between sending the command, then reading the returned data. */ #ifdef XPT2046_NO_BUSY /* REVISIT: Currently, XPT2046 reports BUSY all of the time. This is * probably GPIO setting issues. But there is this cryptic statement in * the XPT2046 spec: "No DCLK delay required with dedicated serial port." */ return false; #else /* XPT2046_NO_BUSY */ #if defined(CONFIG_DEBUG_INPUT) && defined(CONFIG_DEBUG_INFO) static bool last = (bool)-1; #endif /* REVISIT: This might need to be inverted */ bool busy = lpc17_gpioread(GPIO_TC_BUSY); #if defined(CONFIG_DEBUG_INPUT) && defined(CONFIG_DEBUG_INFO) if (busy != last) { iinfo("busy:%d\n", busy); last = busy; } #endif return busy; #endif /* XPT2046_NO_BUSY */ } 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 = !lpc17_gpioread(GPIO_TC_PENIRQ); iinfo("pendown:%d\n", pendown); return pendown; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: open1788_tsc_setup * * Description: * This function is called by board-bringup 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 open1788_tsc_setup(int minor) { FAR struct spi_dev_s *dev; int ret; iinfo("minor:%d\n", minor); DEBUGASSERT(minor == 0); /* Configure and enable the XPT2046 PENIRQ pin as an interrupting input. */ (void)lpc17_configgpio(GPIO_TC_PENIRQ); /* Configure the XPT2046 BUSY pin as a normal input. */ #ifndef XPT2046_NO_BUSY (void)lpc17_configgpio(GPIO_TC_BUSY); #endif /* Get an instance of the SPI interface */ dev = lpc17_sspbus_initialize(CONFIG_ADS7843E_SPIDEV); if (!dev) { ierr("ERROR: Failed to initialize SPI bus %d\n", CONFIG_ADS7843E_SPIDEV); return -ENODEV; } /* Initialize and register the SPI touchscreen device */ ret = ads7843e_register(dev, &g_tscinfo, CONFIG_ADS7843E_DEVMINOR); if (ret < 0) { ierr("ERROR: Failed to register touchscreen device minor=%d\n", CONFIG_ADS7843E_DEVMINOR); /* up_spiuninitialize(dev); */ return -ENODEV; } return OK; } #endif /* CONFIG_INPUT_ADS7843E */