modify nuttx bug of lack of files
This commit is contained in:
TangYiwen123
@@ -0,0 +1,816 @@
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/****************************************************************************
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* drivers/input/button_upper.c
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*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership. The
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* ASF licenses this file to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance with the
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* License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*
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****************************************************************************/
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/* This file provides a driver for a button input devices.
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*
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* The buttons driver exports a standard character driver interface. By
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* convention, the button driver is registered as an input device at
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* /dev/btnN where N uniquely identifies the driver instance.
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*/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <nuttx/config.h>
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#include <sys/types.h>
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#include <stdbool.h>
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#include <string.h>
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#include <poll.h>
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#include <errno.h>
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#include <debug.h>
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#include <nuttx/kmalloc.h>
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#include <nuttx/signal.h>
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#include <nuttx/random.h>
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#include <nuttx/fs/fs.h>
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#include <nuttx/input/buttons.h>
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#include <nuttx/irq.h>
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/****************************************************************************
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* Private Types
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****************************************************************************/
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/* This structure provides the state of one button driver */
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struct btn_upperhalf_s
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{
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/* Saved binding to the lower half button driver */
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FAR const struct btn_lowerhalf_s *bu_lower;
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btn_buttonset_t bu_enabled; /* Set of currently enabled button interrupts */
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btn_buttonset_t bu_sample; /* Last sampled button states */
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sem_t bu_exclsem; /* Supports exclusive access to the device */
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/* The following is a singly linked list of open references to the
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* button device.
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*/
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FAR struct btn_open_s *bu_open;
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};
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/* This structure describes the state of one open button driver instance */
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struct btn_open_s
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{
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/* Supports a singly linked list */
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FAR struct btn_open_s *bo_flink;
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/* The following will be true if we are closing */
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volatile bool bo_closing;
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/* Button event notification information */
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pid_t bo_pid;
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struct btn_notify_s bo_notify;
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struct sigwork_s bo_work;
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/* Poll event information */
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struct btn_pollevents_s bo_pollevents;
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/* The following is a list if poll structures of threads waiting for
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* driver events.
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*/
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FAR struct pollfd *bo_fds[CONFIG_INPUT_BUTTONS_NPOLLWAITERS];
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};
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/****************************************************************************
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* Private Function Prototypes
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****************************************************************************/
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/* Semaphore helpers */
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static inline int btn_takesem(sem_t *sem);
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#define btn_givesem(s) nxsem_post(s);
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/* Sampling and Interrupt handling */
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static void btn_enable(FAR struct btn_upperhalf_s *priv);
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static void btn_interrupt(FAR const struct btn_lowerhalf_s *lower,
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FAR void *arg);
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/* Sampling */
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static void btn_sample(FAR struct btn_upperhalf_s *priv);
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/* Character driver methods */
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static int btn_open(FAR struct file *filep);
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static int btn_close(FAR struct file *filep);
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static ssize_t btn_read(FAR struct file *filep, FAR char *buffer,
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size_t buflen);
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static int btn_ioctl(FAR struct file *filep, int cmd,
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unsigned long arg);
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static int btn_poll(FAR struct file *filep, FAR struct pollfd *fds,
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bool setup);
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/****************************************************************************
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* Private Data
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****************************************************************************/
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static const struct file_operations btn_fops =
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{
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btn_open, /* open */
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btn_close, /* close */
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btn_read, /* read */
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NULL, /* write */
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NULL, /* seek */
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btn_ioctl, /* ioctl */
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btn_poll /* poll */
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};
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/****************************************************************************
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* Private Functions
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****************************************************************************/
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/****************************************************************************
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* Name: btn_takesem
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****************************************************************************/
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static inline int btn_takesem(sem_t *sem)
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{
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return nxsem_wait(sem);
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}
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/****************************************************************************
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* Name: btn_enable
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****************************************************************************/
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static void btn_enable(FAR struct btn_upperhalf_s *priv)
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{
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FAR const struct btn_lowerhalf_s *lower;
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FAR struct btn_open_s *opriv;
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btn_buttonset_t press;
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btn_buttonset_t release;
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irqstate_t flags;
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DEBUGASSERT(priv && priv->bu_lower);
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lower = priv->bu_lower;
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/* This routine is called both task level and interrupt level, so
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* interrupts must be disabled.
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*/
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flags = enter_critical_section();
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/* Visit each opened reference to the device */
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press = 0;
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release = 0;
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for (opriv = priv->bu_open; opriv; opriv = opriv->bo_flink)
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{
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/* OR in the poll event buttons */
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press |= opriv->bo_pollevents.bp_press;
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release |= opriv->bo_pollevents.bp_release;
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/* OR in the signal events */
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press |= opriv->bo_notify.bn_press;
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release |= opriv->bo_notify.bn_release;
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}
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/* Enable/disable button interrupts */
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DEBUGASSERT(lower->bl_enable);
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if (press != 0 || release != 0)
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{
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/* Enable interrupts with the new button set */
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lower->bl_enable(lower, press, release,
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(btn_handler_t)btn_interrupt, priv);
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}
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else
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{
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/* Disable further interrupts */
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lower->bl_enable(lower, 0, 0, NULL, NULL);
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}
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leave_critical_section(flags);
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}
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/****************************************************************************
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* Name: btn_interrupt
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****************************************************************************/
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static void btn_interrupt(FAR const struct btn_lowerhalf_s *lower,
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FAR void *arg)
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{
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FAR struct btn_upperhalf_s *priv = (FAR struct btn_upperhalf_s *)arg;
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DEBUGASSERT(priv);
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/* Process the next sample */
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btn_sample(priv);
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}
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/****************************************************************************
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* Name: btn_sample
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****************************************************************************/
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static void btn_sample(FAR struct btn_upperhalf_s *priv)
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{
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FAR const struct btn_lowerhalf_s *lower;
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FAR struct btn_open_s *opriv;
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btn_buttonset_t sample;
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btn_buttonset_t change;
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btn_buttonset_t press;
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btn_buttonset_t release;
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irqstate_t flags;
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int i;
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DEBUGASSERT(priv && priv->bu_lower);
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lower = priv->bu_lower;
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/* This routine is called both task level and interrupt level, so
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* interrupts must be disabled.
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*/
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flags = enter_critical_section();
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/* Sample the new button state */
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DEBUGASSERT(lower->bl_buttons);
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sample = lower->bl_buttons(lower);
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add_ui_randomness(sample);
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/* Determine which buttons have been newly pressed and which have been
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* newly released.
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*/
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change = sample ^ priv->bu_sample;
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press = change & sample;
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DEBUGASSERT(lower->bl_supported);
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release = change & (lower->bl_supported(lower) & ~sample);
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/* Visit each opened reference to the device */
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for (opriv = priv->bu_open; opriv; opriv = opriv->bo_flink)
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{
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/* Have any poll events occurred? */
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if ((press & opriv->bo_pollevents.bp_press) != 0 ||
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(release & opriv->bo_pollevents.bp_release) != 0)
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{
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/* Yes.. Notify all waiters */
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for (i = 0; i < CONFIG_INPUT_BUTTONS_NPOLLWAITERS; i++)
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{
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FAR struct pollfd *fds = opriv->bo_fds[i];
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if (fds)
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{
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fds->revents |= (fds->events & POLLIN);
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if (fds->revents != 0)
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{
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iinfo("Report events: %02x\n", fds->revents);
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nxsem_post(fds->sem);
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}
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}
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}
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}
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/* Have any signal events occurred? */
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if ((press & opriv->bo_notify.bn_press) != 0 ||
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(release & opriv->bo_notify.bn_release) != 0)
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{
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/* Yes.. Signal the waiter */
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opriv->bo_notify.bn_event.sigev_value.sival_int = sample;
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nxsig_notification(opriv->bo_pid, &opriv->bo_notify.bn_event,
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SI_QUEUE, &opriv->bo_work);
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}
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}
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/* Enable/disable interrupt handling */
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btn_enable(priv);
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priv->bu_sample = sample;
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leave_critical_section(flags);
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}
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/****************************************************************************
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* Name: btn_open
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****************************************************************************/
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static int btn_open(FAR struct file *filep)
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{
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FAR struct inode *inode;
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FAR struct btn_upperhalf_s *priv;
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FAR struct btn_open_s *opriv;
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FAR const struct btn_lowerhalf_s *lower;
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btn_buttonset_t supported;
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int ret;
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DEBUGASSERT(filep && filep->f_inode);
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inode = filep->f_inode;
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DEBUGASSERT(inode->i_private);
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priv = (FAR struct btn_upperhalf_s *)inode->i_private;
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/* Get exclusive access to the driver structure */
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ret = btn_takesem(&priv->bu_exclsem);
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if (ret < 0)
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{
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ierr("ERROR: btn_takesem failed: %d\n", ret);
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return ret;
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}
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/* Allocate a new open structure */
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opriv = (FAR struct btn_open_s *)kmm_zalloc(sizeof(struct btn_open_s));
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if (!opriv)
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{
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ierr("ERROR: Failed to allocate open structure\n");
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ret = -ENOMEM;
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goto errout_with_sem;
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}
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/* Initialize the open structure */
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lower = priv->bu_lower;
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DEBUGASSERT(lower && lower->bl_supported);
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supported = lower->bl_supported(lower);
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opriv->bo_pollevents.bp_press = supported;
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opriv->bo_pollevents.bp_release = supported;
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/* Attach the open structure to the device */
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opriv->bo_flink = priv->bu_open;
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priv->bu_open = opriv;
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/* Attach the open structure to the file structure */
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filep->f_priv = (FAR void *)opriv;
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ret = OK;
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/* Enable/disable interrupt handling */
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btn_enable(priv);
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errout_with_sem:
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btn_givesem(&priv->bu_exclsem);
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return ret;
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}
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/****************************************************************************
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* Name: btn_close
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****************************************************************************/
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static int btn_close(FAR struct file *filep)
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{
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FAR struct inode *inode;
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FAR struct btn_upperhalf_s *priv;
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FAR struct btn_open_s *opriv;
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FAR struct btn_open_s *curr;
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FAR struct btn_open_s *prev;
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irqstate_t flags;
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bool closing;
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int ret;
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DEBUGASSERT(filep && filep->f_priv && filep->f_inode);
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opriv = filep->f_priv;
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inode = filep->f_inode;
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DEBUGASSERT(inode->i_private);
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priv = (FAR struct btn_upperhalf_s *)inode->i_private;
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/* Handle an improbable race conditions with the following atomic test
|
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* and set.
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*
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* This is actually a pretty feeble attempt to handle this. The
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* improbable race condition occurs if two different threads try to
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* close the button driver at the same time. The rule: don't do
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* that! It is feeble because we do not really enforce stale pointer
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* detection anyway.
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*/
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|
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flags = enter_critical_section();
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closing = opriv->bo_closing;
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opriv->bo_closing = true;
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leave_critical_section(flags);
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|
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if (closing)
|
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{
|
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/* Another thread is doing the close */
|
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|
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return OK;
|
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}
|
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|
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/* Get exclusive access to the driver structure */
|
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|
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ret = btn_takesem(&priv->bu_exclsem);
|
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if (ret < 0)
|
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{
|
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ierr("ERROR: btn_takesem failed: %d\n", ret);
|
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return ret;
|
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}
|
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|
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/* Find the open structure in the list of open structures for the device */
|
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|
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for (prev = NULL, curr = priv->bu_open;
|
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curr && curr != opriv;
|
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prev = curr, curr = curr->bo_flink);
|
||||
|
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DEBUGASSERT(curr);
|
||||
if (!curr)
|
||||
{
|
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ierr("ERROR: Failed to find open entry\n");
|
||||
ret = -ENOENT;
|
||||
goto errout_with_exclsem;
|
||||
}
|
||||
|
||||
/* Remove the structure from the device */
|
||||
|
||||
if (prev)
|
||||
{
|
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prev->bo_flink = opriv->bo_flink;
|
||||
}
|
||||
else
|
||||
{
|
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priv->bu_open = opriv->bo_flink;
|
||||
}
|
||||
|
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/* Cancel any pending notification */
|
||||
|
||||
nxsig_cancel_notification(&opriv->bo_work);
|
||||
|
||||
/* And free the open structure */
|
||||
|
||||
kmm_free(opriv);
|
||||
|
||||
/* Enable/disable interrupt handling */
|
||||
|
||||
btn_enable(priv);
|
||||
ret = OK;
|
||||
|
||||
errout_with_exclsem:
|
||||
btn_givesem(&priv->bu_exclsem);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: btn_read
|
||||
****************************************************************************/
|
||||
|
||||
static ssize_t btn_read(FAR struct file *filep, FAR char *buffer,
|
||||
size_t len)
|
||||
{
|
||||
FAR struct inode *inode;
|
||||
FAR struct btn_upperhalf_s *priv;
|
||||
FAR const struct btn_lowerhalf_s *lower;
|
||||
int ret;
|
||||
|
||||
DEBUGASSERT(filep && filep->f_inode);
|
||||
inode = filep->f_inode;
|
||||
DEBUGASSERT(inode->i_private);
|
||||
priv = (FAR struct btn_upperhalf_s *)inode->i_private;
|
||||
|
||||
/* Make sure that the buffer is sufficiently large to hold at least one
|
||||
* complete sample.
|
||||
*
|
||||
* REVISIT: Should also check buffer alignment.
|
||||
*/
|
||||
|
||||
if (len < sizeof(btn_buttonset_t))
|
||||
{
|
||||
ierr("ERROR: buffer too small: %lu\n", (unsigned long)len);
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/* Get exclusive access to the driver structure */
|
||||
|
||||
ret = btn_takesem(&priv->bu_exclsem);
|
||||
if (ret < 0)
|
||||
{
|
||||
ierr("ERROR: btn_takesem failed: %d\n", ret);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* Read and return the current state of the buttons */
|
||||
|
||||
lower = priv->bu_lower;
|
||||
DEBUGASSERT(lower && lower->bl_buttons);
|
||||
*(FAR btn_buttonset_t *)buffer = lower->bl_buttons(lower);
|
||||
|
||||
btn_givesem(&priv->bu_exclsem);
|
||||
return (ssize_t)sizeof(btn_buttonset_t);
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: btn_ioctl
|
||||
****************************************************************************/
|
||||
|
||||
static int btn_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
|
||||
{
|
||||
FAR struct inode *inode;
|
||||
FAR struct btn_upperhalf_s *priv;
|
||||
FAR struct btn_open_s *opriv;
|
||||
FAR const struct btn_lowerhalf_s *lower;
|
||||
int ret;
|
||||
|
||||
DEBUGASSERT(filep && filep->f_priv && filep->f_inode);
|
||||
opriv = filep->f_priv;
|
||||
inode = filep->f_inode;
|
||||
DEBUGASSERT(inode->i_private);
|
||||
priv = (FAR struct btn_upperhalf_s *)inode->i_private;
|
||||
|
||||
/* Get exclusive access to the driver structure */
|
||||
|
||||
ret = btn_takesem(&priv->bu_exclsem);
|
||||
if (ret < 0)
|
||||
{
|
||||
ierr("ERROR: btn_takesem failed: %d\n", ret);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* Handle the ioctl command */
|
||||
|
||||
ret = -EINVAL;
|
||||
switch (cmd)
|
||||
{
|
||||
/* Command: BTNIOC_SUPPORTED
|
||||
* Description: Report the set of button events supported by the
|
||||
* hardware;
|
||||
* Argument: A pointer to writeable integer value in which to return
|
||||
* the set of supported buttons.
|
||||
* Return: Zero (OK) on success. Minus one will be returned on
|
||||
* failure with the errno value set appropriately.
|
||||
*/
|
||||
|
||||
case BTNIOC_SUPPORTED:
|
||||
{
|
||||
FAR btn_buttonset_t *supported =
|
||||
(FAR btn_buttonset_t *)((uintptr_t)arg);
|
||||
|
||||
if (supported)
|
||||
{
|
||||
lower = priv->bu_lower;
|
||||
DEBUGASSERT(lower && lower->bl_supported);
|
||||
|
||||
*supported = lower->bl_supported(lower);
|
||||
ret = OK;
|
||||
}
|
||||
}
|
||||
break;
|
||||
|
||||
/* Command: BTNIOC_POLLEVENTS
|
||||
* Description: Specify the set of button events that can cause a poll()
|
||||
* to awaken. The default is all button depressions and
|
||||
* all button releases (all supported buttons);
|
||||
* Argument: A read-only pointer to an instance of struct
|
||||
* btn_pollevents_s
|
||||
* Return: Zero (OK) on success. Minus one will be returned on
|
||||
* failure with the errno value set appropriately.
|
||||
*/
|
||||
|
||||
case BTNIOC_POLLEVENTS:
|
||||
{
|
||||
FAR struct btn_pollevents_s *pollevents =
|
||||
(FAR struct btn_pollevents_s *)((uintptr_t)arg);
|
||||
|
||||
if (pollevents)
|
||||
{
|
||||
/* Save the poll events */
|
||||
|
||||
opriv->bo_pollevents.bp_press = pollevents->bp_press;
|
||||
opriv->bo_pollevents.bp_release = pollevents->bp_release;
|
||||
|
||||
/* Enable/disable interrupt handling */
|
||||
|
||||
btn_enable(priv);
|
||||
ret = OK;
|
||||
}
|
||||
}
|
||||
break;
|
||||
|
||||
/* Command: BTNIOC_REGISTER
|
||||
* Description: Register to receive a signal whenever there is a change
|
||||
* in any of the discrete buttone inputs. This feature,
|
||||
* of course, depends upon interrupt GPIO support from the
|
||||
* platform.
|
||||
* Argument: A read-only pointer to an instance of struct
|
||||
* btn_notify_s
|
||||
* Return: Zero (OK) on success. Minus one will be returned on
|
||||
* failure with the errno value set appropriately.
|
||||
*/
|
||||
|
||||
case BTNIOC_REGISTER:
|
||||
{
|
||||
FAR struct btn_notify_s *notify =
|
||||
(FAR struct btn_notify_s *)((uintptr_t)arg);
|
||||
|
||||
if (notify)
|
||||
{
|
||||
/* Save the notification events */
|
||||
|
||||
opriv->bo_notify.bn_press = notify->bn_press;
|
||||
opriv->bo_notify.bn_release = notify->bn_release;
|
||||
opriv->bo_notify.bn_event = notify->bn_event;
|
||||
opriv->bo_pid = getpid();
|
||||
|
||||
/* Enable/disable interrupt handling */
|
||||
|
||||
btn_enable(priv);
|
||||
ret = OK;
|
||||
}
|
||||
}
|
||||
break;
|
||||
|
||||
default:
|
||||
ierr("ERROR: Unrecognized command: %d\n", cmd);
|
||||
ret = -ENOTTY;
|
||||
break;
|
||||
}
|
||||
|
||||
btn_givesem(&priv->bu_exclsem);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: btn_poll
|
||||
****************************************************************************/
|
||||
|
||||
static int btn_poll(FAR struct file *filep, FAR struct pollfd *fds,
|
||||
bool setup)
|
||||
{
|
||||
FAR struct inode *inode;
|
||||
FAR struct btn_upperhalf_s *priv;
|
||||
FAR struct btn_open_s *opriv;
|
||||
int ret;
|
||||
int i;
|
||||
|
||||
DEBUGASSERT(filep && filep->f_priv && filep->f_inode);
|
||||
opriv = filep->f_priv;
|
||||
inode = filep->f_inode;
|
||||
DEBUGASSERT(inode->i_private);
|
||||
priv = (FAR struct btn_upperhalf_s *)inode->i_private;
|
||||
|
||||
/* Get exclusive access to the driver structure */
|
||||
|
||||
ret = btn_takesem(&priv->bu_exclsem);
|
||||
if (ret < 0)
|
||||
{
|
||||
ierr("ERROR: btn_takesem failed: %d\n", ret);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* Are we setting up the poll? Or tearing it down? */
|
||||
|
||||
if (setup)
|
||||
{
|
||||
/* This is a request to set up the poll. Find an available
|
||||
* slot for the poll structure reference
|
||||
*/
|
||||
|
||||
for (i = 0; i < CONFIG_INPUT_BUTTONS_NPOLLWAITERS; i++)
|
||||
{
|
||||
/* Find an available slot */
|
||||
|
||||
if (!opriv->bo_fds[i])
|
||||
{
|
||||
/* Bind the poll structure and this slot */
|
||||
|
||||
opriv->bo_fds[i] = fds;
|
||||
fds->priv = &opriv->bo_fds[i];
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
if (i >= CONFIG_INPUT_BUTTONS_NPOLLWAITERS)
|
||||
{
|
||||
ierr("ERROR: Too many poll waiters\n");
|
||||
fds->priv = NULL;
|
||||
ret = -EBUSY;
|
||||
goto errout_with_dusem;
|
||||
}
|
||||
}
|
||||
else if (fds->priv)
|
||||
{
|
||||
/* This is a request to tear down the poll. */
|
||||
|
||||
FAR struct pollfd **slot = (FAR struct pollfd **)fds->priv;
|
||||
|
||||
#ifdef CONFIG_DEBUG_FEATURES
|
||||
if (!slot)
|
||||
{
|
||||
ierr("ERROR: Poll slot not found\n");
|
||||
ret = -EIO;
|
||||
goto errout_with_dusem;
|
||||
}
|
||||
#endif
|
||||
|
||||
/* Remove all memory of the poll setup */
|
||||
|
||||
*slot = NULL;
|
||||
fds->priv = NULL;
|
||||
}
|
||||
|
||||
errout_with_dusem:
|
||||
btn_enable(priv);
|
||||
btn_givesem(&priv->bu_exclsem);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Public Functions
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Name: btn_register
|
||||
*
|
||||
* Description:
|
||||
* Bind the lower half button driver to an instance of the upper half
|
||||
* button driver and register the composite character driver as the
|
||||
* specified device.
|
||||
*
|
||||
* Input Parameters:
|
||||
* devname - The name of the button device to be registered.
|
||||
* This should be a string of the form "/dev/btnN" where N is the
|
||||
* minor device number.
|
||||
* lower - An instance of the platform-specific button lower half driver.
|
||||
*
|
||||
* Returned Value:
|
||||
* Zero (OK) is returned on success. Otherwise a negated errno value is
|
||||
* returned to indicate the nature of the failure.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
int btn_register(FAR const char *devname,
|
||||
FAR const struct btn_lowerhalf_s *lower)
|
||||
{
|
||||
FAR struct btn_upperhalf_s *priv;
|
||||
int ret;
|
||||
|
||||
DEBUGASSERT(devname && lower);
|
||||
|
||||
/* Allocate a new button driver instance */
|
||||
|
||||
priv = (FAR struct btn_upperhalf_s *)
|
||||
kmm_zalloc(sizeof(struct btn_upperhalf_s));
|
||||
|
||||
if (!priv)
|
||||
{
|
||||
ierr("ERROR: Failed to allocate device structure\n");
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
/* Make sure that all button interrupts are disabled */
|
||||
|
||||
DEBUGASSERT(lower->bl_enable);
|
||||
lower->bl_enable(lower, 0, 0, NULL, NULL);
|
||||
|
||||
/* Initialize the new button driver instance */
|
||||
|
||||
priv->bu_lower = lower;
|
||||
nxsem_init(&priv->bu_exclsem, 0, 1);
|
||||
|
||||
DEBUGASSERT(lower->bl_buttons);
|
||||
priv->bu_sample = lower->bl_buttons(lower);
|
||||
|
||||
/* And register the button driver */
|
||||
|
||||
ret = register_driver(devname, &btn_fops, 0666, priv);
|
||||
if (ret < 0)
|
||||
{
|
||||
ierr("ERROR: register_driver failed: %d\n", ret);
|
||||
goto errout_with_priv;
|
||||
}
|
||||
|
||||
return OK;
|
||||
|
||||
errout_with_priv:
|
||||
nxsem_destroy(&priv->bu_exclsem);
|
||||
kmm_free(priv);
|
||||
return ret;
|
||||
}
|
||||
Reference in New Issue
Block a user