/************************************************************************************ * configs/sam4e-ek/src/sam_ads7843e.c * * Copyright (C) 2014 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 "sam_gpio.h" #include "sam_spi.h" #include "sam4e-ek.h" #if defined(CONFIG_INPUT) && defined(CONFIG_INPUT_ADS7843E) /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* Configuration ************************************************************/ #ifndef CONFIG_SAM34_SPI0 # error "Touchscreen support requires CONFIG_SAM34_SPI0" #endif #ifndef CONFIG_SAM34_GPIOA_IRQ # error "Touchscreen support requires CONFIG_SAM34_GPIOA_IRQ" #endif #ifndef CONFIG_ADS7843E_FREQUENCY # define CONFIG_ADS7843E_FREQUENCY 500000 #endif #ifndef CONFIG_ADS7843E_SPIDEV # define CONFIG_ADS7843E_SPIDEV TSC_CSNUM #endif #if CONFIG_ADS7843E_SPIDEV != TSC_CSNUM # error "CONFIG_ADS7843E_SPIDEV must have the same value as TSC_CSNUM" #endif #ifndef CONFIG_ADS7843E_DEVMINOR # define CONFIG_ADS7843E_DEVMINOR 0 #endif /**************************************************************************** * Static 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 writeable because, under certain circumstances, the driver * may modify frequency or X plate resistance values. */ 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 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) { /* Attach the ADS7843E interrupt */ iinfo("Attaching %p to IRQ %d\n", isr, SAM_TCS_IRQ); return irq_attach(SAM_TCS_IRQ, isr, NULL); } static void tsc_enable(FAR struct ads7843e_config_s *state, bool enable) { /* Attach and enable, or detach and disable */ iinfo("IRQ:%d enable:%d\n", SAM_TCS_IRQ, enable); if (enable) { sam_gpioirqenable(SAM_TCS_IRQ); } else { sam_gpioirqdisable(SAM_TCS_IRQ); } } static void tsc_clear(FAR struct ads7843e_config_s *state) { /* Does nothing */ } static bool tsc_busy(FAR struct ads7843e_config_s *state) { #if defined(CONFIG_DEBUG_INPUT) && defined(CONFIG_DEBUG_INFO) static bool last = (bool)-1; #endif /* BUSY is high impedance when CS is high (not selected). When CS is * is low, BUSY is active high. */ bool busy = sam_gpioread(GPIO_TCS_BUSY); #if defined(CONFIG_DEBUG_INPUT) && defined(CONFIG_DEBUG_INFO) if (busy != last) { iinfo("busy:%d\n", busy); last = busy; } #endif return busy; } static bool tsc_pendown(FAR struct ads7843e_config_s *state) { /* The /PENIRQ value is active low */ bool pendown = !sam_gpioread(GPIO_TCS_IRQ); iinfo("pendown:%d\n", pendown); return pendown; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: board_tsc_setup * * 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 board_tsc_setup(int minor) { FAR struct spi_dev_s *dev; int ret; iinfo("minor %d\n", minor); DEBUGASSERT(minor == 0); /* Configure and enable the ADS7843E interrupt pin as an input */ (void)sam_configgpio(GPIO_TCS_BUSY); (void)sam_configgpio(GPIO_TCS_IRQ); /* Configure the PIO interrupt */ sam_gpioirq(GPIO_TCS_IRQ); /* Get an instance of the SPI interface for the touchscreen chip select */ dev = sam_spibus_initialize(TSC_CSNUM); if (!dev) { ierr("ERROR: Failed to initialize SPI chip select %d\n", TSC_CSNUM); return -ENODEV; } /* Initialize and register the SPI touschscreen device */ ret = ads7843e_register(dev, &g_tscinfo, CONFIG_ADS7843E_DEVMINOR); if (ret < 0) { ierr("ERROR: Failed to initialize SPI chip select %d\n", TSC_CSNUM); /* sam_spibus_uninitialize(dev); */ return -ENODEV; } return OK; } #endif /* CONFIG_INPUT && CONFIG_INPUT_ADS7843E */