/**************************************************************************** * drivers/ioexpander/gpio_lower_half.c * * Copyright (C) 2016, 2018 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 #ifdef CONFIG_GPIO_LOWER_HALF /**************************************************************************** * Private Types ****************************************************************************/ /* GPIO lower half driver state */ struct gplh_dev_s { /* Publicly visible lower-half state */ struct gpio_dev_s gpio; /* Private lower half data follows */ uint8_t pin; /* I/O expander pin ID */ FAR struct ioexpander_dev_s *ioe; /* Contain I/O expander interface */ #ifdef CONFIG_IOEXPANDER_INT_ENABLE FAR void *handle; /* Interrupt attach handle */ pin_interrupt_t callback; /* Interrupt callback */ #endif }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ #ifdef CONFIG_IOEXPANDER_INT_ENABLE static int gplh_handler(FAR struct ioexpander_dev_s *ioe, ioe_pinset_t pinset, FAR void *arg); #endif /* GPIO lower half interface methods */ static int gplh_read(FAR struct gpio_dev_s *gpio, FAR bool *value); static int gplh_write(FAR struct gpio_dev_s *gpio, bool value); #ifdef CONFIG_IOEXPANDER_INT_ENABLE static int gplh_attach(FAR struct gpio_dev_s *gpio, pin_interrupt_t callback); static int gplh_enable(FAR struct gpio_dev_s *gpio, bool enable); #endif static int gplh_setpintype(FAR struct gpio_dev_s *gpio, enum gpio_pintype_e pintype); /**************************************************************************** * Private Data ****************************************************************************/ /* GPIO Lower Half interface operations */ static const struct gpio_operations_s g_gplh_ops = { gplh_read, /* read */ gplh_write, /* write */ #ifdef CONFIG_IOEXPANDER_INT_ENABLE gplh_attach, /* attach */ gplh_enable, /* enable */ #else NULL, /* attach */ NULL, /* enable */ #endif gplh_setpintype, }; /* REVISIT: The following violates the NuttX coding standard requirement * for C89 compatibility. */ static const uint32_t g_gplh_inttype[] = { [GPIO_INPUT_PIN] = IOEXPANDER_VAL_DISABLE, [GPIO_INTERRUPT_PIN] = CONFIG_GPIO_LOWER_HALF_INTTYPE, [GPIO_INTERRUPT_HIGH_PIN] = IOEXPANDER_VAL_HIGH, [GPIO_INTERRUPT_LOW_PIN] = IOEXPANDER_VAL_LOW, [GPIO_INTERRUPT_RISING_PIN] = IOEXPANDER_VAL_RISING, [GPIO_INTERRUPT_FALLING_PIN] = IOEXPANDER_VAL_FALLING, [GPIO_INTERRUPT_BOTH_PIN] = IOEXPANDER_VAL_BOTH, }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: gplh_handler * * Description: * I/O expander interrupt callback function. * ****************************************************************************/ #ifdef CONFIG_IOEXPANDER_INT_ENABLE static int gplh_handler(FAR struct ioexpander_dev_s *ioe, ioe_pinset_t pinset, FAR void *arg) { FAR struct gplh_dev_s *priv = (FAR struct gplh_dev_s *)arg; DEBUGASSERT(priv != NULL && priv->callback != NULL); gpioinfo("pin%u: pinset: %lx callback=%p\n", priv->pin, (unsigned long)pinset, priv->callback); /* We received the callback from the I/O expander, forward this to the * upper half GPIO driver via its callback. */ return priv->callback(&priv->gpio, priv->pin); } #endif /**************************************************************************** * Name: gplh_read * * Description: * Read the value of the I/O expander pin. * ****************************************************************************/ static int gplh_read(FAR struct gpio_dev_s *gpio, FAR bool *value) { FAR struct gplh_dev_s *priv = (FAR struct gplh_dev_s *)gpio; DEBUGASSERT(priv != NULL && priv->ioe != NULL && value != NULL); gpioinfo("pin%u: value=%p\n", priv->pin, value); /* Return the value from the I/O expander */ return IOEXP_READPIN(priv->ioe, priv->pin, value); } /**************************************************************************** * Name: gplh_write * * Description: * Set the value of an I/O expander output pin * ****************************************************************************/ static int gplh_write(FAR struct gpio_dev_s *gpio, bool value) { FAR struct gplh_dev_s *priv = (FAR struct gplh_dev_s *)gpio; DEBUGASSERT(priv != NULL && priv->ioe != NULL); gpioinfo("pin%u: value=%u\n", priv->pin, value); /* Write the value using the I/O expander */ return IOEXP_WRITEPIN(priv->ioe, priv->pin, value); } /**************************************************************************** * Name: gplh_attach * * Description: * Detach and disable any current interrupt on the pin. Save the callback * information for use when the pin interrupt is enabled. * ****************************************************************************/ #ifdef CONFIG_IOEXPANDER_INT_ENABLE static int gplh_attach(FAR struct gpio_dev_s *gpio, pin_interrupt_t callback) { FAR struct gplh_dev_s *priv = (FAR struct gplh_dev_s *)gpio; DEBUGASSERT(priv != NULL && priv->ioe != NULL); gpioinfo("pin%u: callback=%p\n", priv->pin, callback); /* Detach and disable any current interrupt on the pin. */ if (priv->handle != NULL) { gpioinfo("pin%u: Detaching handle %p\n", priv->pin, priv->handle); IOEP_DETACH(priv->ioe, priv->handle); priv->handle = NULL; } /* Save the callback function pointer for use when the pin interrupt * is enabled. */ priv->callback = callback; return OK; } #endif /**************************************************************************** * Name: gplh_enable * * Description: * Enable or disable the I/O expander pin interrupt * ****************************************************************************/ #ifdef CONFIG_IOEXPANDER_INT_ENABLE static int gplh_enable(FAR struct gpio_dev_s *gpio, bool enable) { FAR struct gplh_dev_s *priv = (FAR struct gplh_dev_s *)gpio; int ret = OK; DEBUGASSERT(priv != NULL && priv->ioe != NULL); gpioinfo("pin%u: %s callback=%p handle=%p\n", priv->pin, enable ? "Enabling" : "Disabling", priv->callback, priv->handle); /* Are we enabling or disabling the pin interrupt? */ if (enable) { /* We are enabling the pin interrupt. Make certain that there is * an interrupt handler already attached. */ if (priv->callback == NULL) { /* No callback has been attached */ gpiowarn("WARNING: pin%u: Attempt to enable before attaching\n", priv->pin); ret = -EPERM; } /* Check if the interrupt is already attached and enabled */ else if (priv->handle == NULL) { #if CONFIG_IOEXPANDER_NPINS <= 64 ioe_pinset_t pinset = ((ioe_pinset_t)1 << priv->pin); #else ioe_pinset_t pinset = ((ioe_pinset_t)priv->pin); #endif /* We have a callback and the callback is not yet attached. * do it now. */ gpioinfo("pin%u: Attaching %p\n", priv->pin, priv->callback); priv->handle = IOEP_ATTACH(priv->ioe, pinset, gplh_handler, priv); if (priv->handle == NULL) { gpioerr("ERROR: pin%u: IOEP_ATTACH() failed\n", priv->pin); ret = -EIO; } } } else { /* Check if we are already detached */ if (priv->handle == NULL) { gpiowarn("WARNING: pin%u: Already detached\n", priv->pin); } else { gpioinfo("pin%u: Detaching handle=%p\n", priv->pin, priv->handle); ret = IOEP_DETACH(priv->ioe, priv->handle); if (ret < 0) { gpioerr("ERROR: pin%u: IOEP_DETACH() failed\n", priv->pin, ret); } /* We are no longer attached */ priv->handle = NULL; } } return ret; } #endif /**************************************************************************** * Name: gplh_setpintype * * Description: * Set I/O expander pin to an appointed gpiopintype * ****************************************************************************/ static int gplh_setpintype(FAR struct gpio_dev_s *gpio, enum gpio_pintype_e pintype) { FAR struct gplh_dev_s *priv = (FAR struct gplh_dev_s *)gpio; FAR struct ioexpander_dev_s *ioe = priv->ioe; uint8_t pin = priv->pin; if (pintype >= GPIO_NPINTYPES) { return -EINVAL; } else if (pintype == GPIO_OUTPUT_PIN) { IOEXP_SETDIRECTION(ioe, pin, IOEXPANDER_DIRECTION_OUT); } else { IOEXP_SETDIRECTION(ioe, pin, IOEXPANDER_DIRECTION_IN); IOEXP_SETOPTION(ioe, pin, IOEXPANDER_OPTION_INTCFG, (FAR void *)g_gplh_inttype[pintype]); } gpio->gp_pintype = pintype; return OK; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: gpio_lower_half * * Description: * Create a GPIO pin device driver instance for an I/O expander pin. * The I/O expander pin must have already been configured by the caller * for the particular pintype. * * Input Parameters: * ioe - An instance of the I/O expander interface * pin - The I/O expander pin number for the driver * pintype - See enum gpio_pintype_e * minor - The minor device number to use when registering the device * * Returned Value: * Zero (OK) on success; a negated errno value on failure. * ****************************************************************************/ int gpio_lower_half(FAR struct ioexpander_dev_s *ioe, unsigned int pin, enum gpio_pintype_e pintype, int minor) { FAR struct gplh_dev_s *priv; FAR struct gpio_dev_s *gpio; int ret; DEBUGASSERT(ioe != NULL && pin < CONFIG_IOEXPANDER_NPINS && (unsigned int)pintype < GPIO_NPINTYPES); #ifndef CONFIG_IOEXPANDER_INT_ENABLE /* If there is no I/O expander interrupt support, then we cannot handle * interrupting pin types. */ DEBUGASSERT(pintype < GPIO_INTERRUPT_PIN); #endif /* Allocate an new instance of the GPIO lower half driver */ priv = (FAR struct gplh_dev_s *)kmm_zalloc(sizeof(struct gplh_dev_s)); if (priv == NULL) { gpioerr("ERROR: Failed to allocate driver state\n"); return -ENOMEM; } /* Initialize the non-zero elements of the newly allocated instance */ priv->pin = (uint8_t)pin; priv->ioe = ioe; gpio = &priv->gpio; gpio->gp_ops = &g_gplh_ops; /* Set pintype */ ret = gplh_setpintype(gpio, pintype); if (ret < 0) { gpioerr("ERROR: gplh_setpintype() failed: %d\n", ret); kmm_free(priv); return ret; } /* Register the GPIO driver */ ret = gpio_pin_register(gpio, minor); if (ret < 0) { gpioerr("ERROR: gpio_pin_register() failed: %d\n", ret); kmm_free(priv); } return ret; } #endif /* CONFIG_GPIO_LOWER_HALF */