/************************************************************************************ * configs/sama5d4-ek/src/sam_maxtouch.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 "up_arch.h" #include "sam_pio.h" #include "sam_twi.h" #include "sama5d4-ek.h" #ifdef HAVE_MAXTOUCH /**************************************************************************** * Pre-Processor Definitions ****************************************************************************/ /* Configuration ************************************************************/ #ifndef CONFIG_SAMA5D4EK_MXT_I2CFREQUENCY # define CONFIG_SAMA5D4EK_MXT_I2CFREQUENCY 500000 #endif #ifndef CONFIG_SAMA5D4EK_MXT_DEVMINOR # define CONFIG_SAMA5D4EK_MXT_DEVMINOR 0 #endif /* The touchscreen communicates on TWI0, I2C address 0x4c */ #define MXT_TWI_BUS 0 #define MXT_I2C_ADDRESS 0x4c /**************************************************************************** * Private Types ****************************************************************************/ struct sama5d4ek_tscinfo_s { /* Standard maXTouch interface */ struct mxt_lower_s lower; /* Extensions for the sama5d4ek board */ mxt_handler_t handler; FAR void *arg; }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ /* IRQ/PIO access callbacks. These operations all hidden behind * callbacks to isolate the maXTouch driver from differences in PIO * 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 maXTouch interrupt handler to the PIO interrupt * enable - Enable or disable the PIO interrupt * clear - Acknowledge/clear any pending PIO interrupt */ static int mxt_attach(FAR const struct mxt_lower_s *lower, mxt_handler_t isr, FAR void *arg); static void mxt_enable(FAR const struct mxt_lower_s *lower, bool enable); static void mxt_clear(FAR const struct mxt_lower_s *lower); /**************************************************************************** * Private Data ****************************************************************************/ /* A reference to a structure of this type must be passed to the maXTouch * driver. This structure provides information about the configuration * of the maXTouch 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 sama5d4ek_tscinfo_s g_mxtinfo = { .lower = { .address = MXT_I2C_ADDRESS, .frequency = CONFIG_SAMA5D4EK_MXT_I2CFREQUENCY, .attach = mxt_attach, .enable = mxt_enable, .clear = mxt_clear, }, }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * IRQ/PIO access callbacks. These operations all hidden behind * callbacks to isolate the maXTouch driver from differences in PIO * 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 maXTouch interrupt handler to the PIO interrupt * enable - Enable or disable the PIO interrupt * clear - Acknowledge/clear any pending PIO interrupt * ****************************************************************************/ static int mxt_attach(FAR const struct mxt_lower_s *lower, mxt_handler_t isr, FAR void *arg) { if (isr) { /* Just save the address of the handler and its argument for now. The * new handler will called via mxt_interrupt() when the interrupt occurs. */ ivdbg("Attaching %p\n", isr); g_mxtinfo.handler = isr; g_mxtinfo.arg = arg; } else { ivdbg("Detaching %p\n", g_mxtinfo.handler); mxt_enable(lower, false); g_mxtinfo.handler = NULL; g_mxtinfo.arg = NULL; } return OK; } static void mxt_enable(FAR const struct mxt_lower_s *lower, bool enable) { /* Enable or disable interrupts */ if (enable && g_mxtinfo.handler) { sam_pioirqenable(IRQ_CHG_MXT); } else { sam_pioirqdisable(IRQ_CHG_MXT); } } static void mxt_clear(FAR const struct mxt_lower_s *lower) { /* Does nothing */ } static int mxt_interrupt(int irq, FAR void *context) { /* Just forward the interrupt to the maXTouch driver */ if (g_mxtinfo.handler) { return g_mxtinfo.handler(&g_mxtinfo.lower, g_mxtinfo.arg); } /* We got an interrupt with no handler. This should not * happen. */ sam_pioirqdisable(IRQ_CHG_MXT); return OK; } /**************************************************************************** * 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 i2c_dev_s *i2c; static bool initialized = false; int ret; idbg("minor %d\n", minor); DEBUGASSERT(minor == 0); /* Have we already initialized? Since we never uninitialize we must prevent * multiple initializations. This is necessary, for example, when the * touchscreen example is used as a built-in application in NSH and can be * called numerous time. It will attempt to initialize each time. */ if (!initialized) { /* Configure the maXTouch CHG interrupt pin */ (void)sam_configpio(PIO_CHG_MXT); /* Get an instance of the I2C interface for the touchscreen chip select */ i2c = up_i2cinitialize(MXT_TWI_BUS); if (!i2c) { idbg("Failed to initialize I2C%d\n", MXT_TWI_BUS); return -ENODEV; } /* Configure maXTouch CHG interrupts */ sam_pioirq(PIO_CHG_MXT); (void)irq_attach(IRQ_CHG_MXT, mxt_interrupt); /* Initialize and register the I2C touchscreen device */ ret = mxt_register(i2c, &g_mxtinfo.lower, CONFIG_SAMA5D4EK_MXT_DEVMINOR); if (ret < 0) { idbg("ERROR: Failed to register touchscreen device\n"); irq_detach(IRQ_CHG_MXT); /* up_i2cuninitialize(i2c); */ return -ENODEV; } /* Now we are initialized */ initialized = true; } 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 maXTouch device. It will * continue to run and process touch interrupts in the background. */ } #endif /* HAVE_MAXTOUCH */