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-rw-r--r--nuttx/drivers/pwm.c676
1 files changed, 0 insertions, 676 deletions
diff --git a/nuttx/drivers/pwm.c b/nuttx/drivers/pwm.c
deleted file mode 100644
index 62fb4d2fb..000000000
--- a/nuttx/drivers/pwm.c
+++ /dev/null
@@ -1,676 +0,0 @@
-/****************************************************************************
- * drivers/pwm.c
- *
- * Copyright (C) 2011-2012 Gregory Nutt. All rights reserved.
- * Author: Gregory Nutt <gnutt@nuttx.org>
- *
- * 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.
- *
- ****************************************************************************/
-
-/****************************************************************************
- * Compilation Switches
- ****************************************************************************/
-
-/****************************************************************************
- * Included Files
- ****************************************************************************/
-
-#include <nuttx/config.h>
-
-#include <sys/types.h>
-#include <stdint.h>
-#include <stdbool.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <string.h>
-#include <semaphore.h>
-#include <fcntl.h>
-#include <assert.h>
-#include <errno.h>
-#include <debug.h>
-
-#include <nuttx/fs/fs.h>
-#include <nuttx/arch.h>
-#include <nuttx/pwm.h>
-
-#include <arch/irq.h>
-
-#ifdef CONFIG_PWM
-
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-/* Debug ********************************************************************/
-/* Non-standard debug that may be enabled just for testing PWM */
-
-#ifdef CONFIG_DEBUG_PWM
-# define pwmdbg dbg
-# define pwmvdbg vdbg
-# define pwmlldbg lldbg
-# define pwmllvdbg llvdbg
-#else
-# define pwmdbg(x...)
-# define pwmvdbg(x...)
-# define pwmlldbg(x...)
-# define pwmllvdbg(x...)
-#endif
-
-/****************************************************************************
- * Private Type Definitions
- ****************************************************************************/
-
-/* This structure describes the state of the upper half driver */
-
-struct pwm_upperhalf_s
-{
- uint8_t crefs; /* The number of times the device has been opened */
- volatile bool started; /* True: pulsed output is being generated */
-#ifdef CONFIG_PWM_PULSECOUNT
- volatile bool waiting; /* True: Caller is waiting for the pulse count to expire */
-#endif
- sem_t exclsem; /* Supports mutual exclusion */
-#ifdef CONFIG_PWM_PULSECOUNT
- sem_t waitsem; /* Used to wait for the pulse count to expire */
-#endif
- struct pwm_info_s info; /* Pulsed output characteristics */
- FAR struct pwm_lowerhalf_s *dev; /* lower-half state */
-};
-
-/****************************************************************************
- * Private Function Prototypes
- ****************************************************************************/
-
-static int pwm_open(FAR struct file *filep);
-static int pwm_close(FAR struct file *filep);
-static ssize_t pwm_read(FAR struct file *filep, FAR char *buffer, size_t buflen);
-static ssize_t pwm_write(FAR struct file *filep, FAR const char *buffer, size_t buflen);
-static int pwm_start(FAR struct pwm_upperhalf_s *upper, unsigned int oflags);
-static int pwm_ioctl(FAR struct file *filep, int cmd, unsigned long arg);
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-static const struct file_operations g_pwmops =
-{
- pwm_open, /* open */
- pwm_close, /* close */
- pwm_read, /* read */
- pwm_write, /* write */
- 0, /* seek */
- pwm_ioctl /* ioctl */
-#ifndef CONFIG_DISABLE_POLL
- , 0 /* poll */
-#endif
-};
-
-/****************************************************************************
- * Private Functions
- ****************************************************************************/
-
-/************************************************************************************
- * Name: pwm_open
- *
- * Description:
- * This function is called whenever the PWM device is opened.
- *
- ************************************************************************************/
-
-static int pwm_open(FAR struct file *filep)
-{
- FAR struct inode *inode = filep->f_inode;
- FAR struct pwm_upperhalf_s *upper = inode->i_private;
- uint8_t tmp;
- int ret;
-
- pwmvdbg("crefs: %d\n", upper->crefs);
-
- /* Get exclusive access to the device structures */
-
- ret = sem_wait(&upper->exclsem);
- if (ret < 0)
- {
- ret = -errno;
- goto errout;
- }
-
- /* Increment the count of references to the device. If this the first
- * time that the driver has been opened for this device, then initialize
- * the device.
- */
-
- tmp = upper->crefs + 1;
- if (tmp == 0)
- {
- /* More than 255 opens; uint8_t overflows to zero */
-
- ret = -EMFILE;
- goto errout_with_sem;
- }
-
- /* Check if this is the first time that the driver has been opened. */
-
- if (tmp == 1)
- {
- FAR struct pwm_lowerhalf_s *lower = upper->dev;
-
- /* Yes.. perform one time hardware initialization. */
-
- DEBUGASSERT(lower->ops->setup != NULL);
- pwmvdbg("calling setup\n");
-
- ret = lower->ops->setup(lower);
- if (ret < 0)
- {
- goto errout_with_sem;
- }
- }
-
- /* Save the new open count on success */
-
- upper->crefs = tmp;
- ret = OK;
-
-errout_with_sem:
- sem_post(&upper->exclsem);
-
-errout:
- return ret;
-}
-
-/************************************************************************************
- * Name: pwm_close
- *
- * Description:
- * This function is called when the PWM device is closed.
- *
- ************************************************************************************/
-
-static int pwm_close(FAR struct file *filep)
-{
- FAR struct inode *inode = filep->f_inode;
- FAR struct pwm_upperhalf_s *upper = inode->i_private;
- int ret;
-
- pwmvdbg("crefs: %d\n", upper->crefs);
-
- /* Get exclusive access to the device structures */
-
- ret = sem_wait(&upper->exclsem);
- if (ret < 0)
- {
- ret = -errno;
- goto errout;
- }
-
- /* Decrement the references to the driver. If the reference count will
- * decrement to 0, then uninitialize the driver.
- */
-
- if (upper->crefs > 1)
- {
- upper->crefs--;
- }
- else
- {
- FAR struct pwm_lowerhalf_s *lower = upper->dev;
-
- /* There are no more references to the port */
-
- upper->crefs = 0;
-
- /* Disable the PWM device */
-
- DEBUGASSERT(lower->ops->shutdown != NULL);
- pwmvdbg("calling shutdown: %d\n");
-
- lower->ops->shutdown(lower);
- }
- ret = OK;
-
-//errout_with_sem:
- sem_post(&upper->exclsem);
-
-errout:
- return ret;
-}
-
-/************************************************************************************
- * Name: pwm_read
- *
- * Description:
- * A dummy read method. This is provided only to satsify the VFS layer.
- *
- ************************************************************************************/
-
-static ssize_t pwm_read(FAR struct file *filep, FAR char *buffer, size_t buflen)
-{
- /* Return zero -- usually meaning end-of-file */
-
- return 0;
-}
-
-/************************************************************************************
- * Name: pwm_write
- *
- * Description:
- * A dummy write method. This is provided only to satsify the VFS layer.
- *
- ************************************************************************************/
-
-static ssize_t pwm_write(FAR struct file *filep, FAR const char *buffer, size_t buflen)
-{
- return 0;
-}
-
-/************************************************************************************
- * Name: pwm_start
- *
- * Description:
- * Handle the PWMIOC_START ioctl command
- *
- ************************************************************************************/
-
-#ifdef CONFIG_PWM_PULSECOUNT
-static int pwm_start(FAR struct pwm_upperhalf_s *upper, unsigned int oflags)
-{
- FAR struct pwm_lowerhalf_s *lower = upper->dev;
- irqstate_t flags;
- int ret = OK;
-
- DEBUGASSERT(upper != NULL && lower->ops->start != NULL);
-
- /* Verify that the PWM is not already running */
-
- if (!upper->started)
- {
- /* Disable interrupts to avoid race conditions */
-
- flags = irqsave();
-
- /* Indicate that if will be waiting for the pulse count to complete.
- * Note that we will only wait if a non-zero pulse count is specified
- * and if the PWM driver was opened in normal, blocking mode. Also
- * assume for now that the pulse train will be successfully started.
- *
- * We do these things before starting the PWM to avoid race conditions.
- */
-
- upper->waiting = (upper->info.count > 0) && ((oflags & O_NONBLOCK) == 0);
- upper->started = true;
-
- /* Invoke the bottom half method to start the pulse train */
-
- ret = lower->ops->start(lower, &upper->info, upper);
-
- /* A return value of zero means that the pulse train was started
- * successfully.
- */
-
- if (ret == OK)
- {
- /* Should we wait for the pulse output to complete? Loop in
- * in case the wakeup form sem_wait() is a false alarm.
- */
-
- while (upper->waiting)
- {
- /* Wait until we are awakened by pwm_expired(). When
- * pwm_expired is called, it will post the waitsem and
- * clear the waiting flag.
- */
-
- int tmp = sem_wait(&upper->waitsem);
- DEBUGASSERT(tmp == OK || errno == EINTR);
- }
- }
- else
- {
- /* Looks like we won't be waiting after all */
-
- pwmvdbg("start failed: %d\n", ret);
- upper->started = false;
- upper->waiting = false;
- }
-
- irqrestore(flags);
- }
-
- return ret;
-}
-#else
-static int pwm_start(FAR struct pwm_upperhalf_s *upper, unsigned int oflags)
-{
- FAR struct pwm_lowerhalf_s *lower = upper->dev;
- int ret = OK;
-
- DEBUGASSERT(upper != NULL && lower->ops->start != NULL);
-
- /* Verify that the PWM is not already running */
-
- if (!upper->started)
- {
- /* Invoke the bottom half method to start the pulse train */
-
- ret = lower->ops->start(lower, &upper->info);
-
- /* A return value of zero means that the pulse train was started
- * successfully.
- */
-
- if (ret == OK)
- {
- /* Indicate that the pulse train has started */
-
- upper->started = true;
- }
- }
-
- return ret;
-}
-#endif
-
-/************************************************************************************
- * Name: pwm_ioctl
- *
- * Description:
- * The standard ioctl method. This is where ALL of the PWM work is done.
- *
- ************************************************************************************/
-
-static int pwm_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
-{
- FAR struct inode *inode = filep->f_inode;
- FAR struct pwm_upperhalf_s *upper = inode->i_private;
- FAR struct pwm_lowerhalf_s *lower = upper->dev;
- int ret;
-
- pwmvdbg("cmd: %d arg: %ld\n", cmd, arg);
-
- /* Get exclusive access to the device structures */
-
- ret = sem_wait(&upper->exclsem);
- if (ret < 0)
- {
- return ret;
- }
-
- /* Handle built-in ioctl commands */
-
- switch (cmd)
- {
- /* PWMIOC_SETCHARACTERISTICS - Set the characteristics of the next pulsed
- * output. This command will neither start nor stop the pulsed output.
- * It will either setup the configuration that will be used when the
- * output is started; or it will change the characteristics of the pulsed
- * output on the fly if the timer is already started.
- *
- * ioctl argument: A read-only reference to struct pwm_info_s that provides
- * the characteristics of the pulsed output.
- */
-
- case PWMIOC_SETCHARACTERISTICS:
- {
- FAR const struct pwm_info_s *info = (FAR const struct pwm_info_s*)((uintptr_t)arg);
- DEBUGASSERT(info != NULL && lower->ops->start != NULL);
-
-#ifdef CONFIG_PWM_PULSECOUNT
- pwmvdbg("PWMIOC_SETCHARACTERISTICS frequency: %d duty: %08x count: %d started: %d\n",
- info->frequency, info->duty, info->count, upper->started);
-#else
- pwmvdbg("PWMIOC_SETCHARACTERISTICS frequency: %d duty: %08x started: %d\n",
- info->frequency, info->duty, upper->started);
-#endif
-
- /* Save the pulse train characteristics */
-
- memcpy(&upper->info, info, sizeof(struct pwm_info_s));
-
- /* If PWM is already running, then re-start it with the new characteristics */
-
- if (upper->started)
- {
-#ifdef CONFIG_PWM_PULSECOUNT
- ret = lower->ops->start(lower, &upper->info, upper);
-#else
- ret = lower->ops->start(lower, &upper->info);
-#endif
- }
- }
- break;
-
- /* PWMIOC_GETCHARACTERISTICS - Get the currently selected characteristics of
- * the pulsed output (independent of whether the output is start or stopped).
- *
- * ioctl argument: A reference to struct pwm_info_s to recevie the
- * characteristics of the pulsed output.
- */
-
- case PWMIOC_GETCHARACTERISTICS:
- {
- FAR struct pwm_info_s *info = (FAR struct pwm_info_s*)((uintptr_t)arg);
- DEBUGASSERT(info != NULL);
-
- memcpy(info, &upper->info, sizeof(struct pwm_info_s));
-
-#ifdef CONFIG_PWM_PULSECOUNT
- pwmvdbg("PWMIOC_GETCHARACTERISTICS frequency: %d duty: %08x count: %d\n",
- info->frequency, info->duty, info->count);
-#else
- pwmvdbg("PWMIOC_GETCHARACTERISTICS frequency: %d duty: %08x\n",
- info->frequency, info->duty);
-#endif
- }
- break;
-
- /* PWMIOC_START - Start the pulsed output. The PWMIOC_SETCHARACTERISTICS
- * command must have previously been sent.
- *
- * ioctl argument: None
- */
-
- case PWMIOC_START:
- {
-#ifdef CONFIG_PWM_PULSECOUNT
- pwmvdbg("PWMIOC_START frequency: %d duty: %08x count: %d started: %d\n",
- upper->info.frequency, upper->info.duty, upper->info.count,
- upper->started);
-#else
- pwmvdbg("PWMIOC_START frequency: %d duty: %08x started: %d\n",
- upper->info.frequency, upper->info.duty, upper->started);
-#endif
- DEBUGASSERT(lower->ops->start != NULL);
-
- /* Start the pulse train */
-
- ret = pwm_start(upper, filep->f_oflags);
- }
- break;
-
- /* PWMIOC_STOP - Stop the pulsed output.
- *
- * ioctl argument: None
- */
-
- case PWMIOC_STOP:
- {
- pwmvdbg("PWMIOC_STOP: started: %d\n", upper->started);
- DEBUGASSERT(lower->ops->stop != NULL);
-
- if (upper->started)
- {
- ret = lower->ops->stop(lower);
- upper->started = false;
-#ifdef CONFIG_PWM_PULSECOUNT
- if (upper->waiting)
- {
- upper->waiting = FALSE;
- }
-#endif
- }
- }
- break;
-
- /* Any unrecognized IOCTL commands might be platform-specific ioctl commands */
-
- default:
- {
- pwmvdbg("Forwarding unrecognized cmd: %d arg: %ld\n", cmd, arg);
- DEBUGASSERT(lower->ops->ioctl != NULL);
- ret = lower->ops->ioctl(lower, cmd, arg);
- }
- break;
- }
-
- sem_post(&upper->exclsem);
- return ret;
-}
-
-/****************************************************************************
- * Public Functions
- ****************************************************************************/
-
-/****************************************************************************
- * Name: pwm_register
- *
- * Description:
- * This function binds an instance of a "lower half" timer driver with the
- * "upper half" PWM device and registers that device so that can be used
- * by application code.
- *
- * When this function is called, the "lower half" driver should be in the
- * reset state (as if the shutdown() method had already been called).
- *
- * Input parameters:
- * path - The full path to the driver to be registers in the NuttX pseudo-
- * filesystem. The recommended convention is to name all PWM drivers
- * as "/dev/pwm0", "/dev/pwm1", etc. where the driver path differs only
- * in the "minor" number at the end of the device name.
- * dev - A pointer to an instance of lower half timer driver. This instance
- * is bound to the PWM driver and must persists as long as the driver
- * persists.
- *
- * Returned Value:
- * Zero on success; a negated errno value on failure.
- *
- ****************************************************************************/
-
-int pwm_register(FAR const char *path, FAR struct pwm_lowerhalf_s *dev)
-{
- FAR struct pwm_upperhalf_s *upper;
-
- /* Allocate the upper-half data structure */
-
- upper = (FAR struct pwm_upperhalf_s *)zalloc(sizeof(struct pwm_upperhalf_s));
- if (!upper)
- {
- pwmdbg("Allocation failed\n");
- return -ENOMEM;
- }
-
- /* Initialize the PWM device structure (it was already zeroed by zalloc()) */
-
- sem_init(&upper->exclsem, 0, 1);
-#ifdef CONFIG_PWM_PULSECOUNT
- sem_init(&upper->waitsem, 0, 0);
-#endif
- upper->dev = dev;
-
- /* Register the PWM device */
-
- pwmvdbg("Registering %s\n", path);
- return register_driver(path, &g_pwmops, 0666, upper);
-}
-
-/****************************************************************************
- * Name: pwm_expired
- *
- * Description:
- * If CONFIG_PWM_PULSECOUNT is defined and the pulse count was configured
- * to a non-zero value, then the "upper half" driver will wait for the
- * pulse count to expire. The sequence of expected events is as follows:
- *
- * 1. The upper half driver calls the start method, providing the lower
- * half driver with the pulse train characteristics. If a fixed
- * number of pulses is required, the 'count' value will be nonzero.
- * 2. The lower half driver's start() methoc must verify that it can
- * support the request pulse train (frequency, duty, AND pulse count).
- * It it cannot, it should return an error. If the pulse count is
- * non-zero, it should set up the hardware for that number of pulses
- * and return success. NOTE: That is CONFIG_PWM_PULSECOUNT is
- * defined, the start() method receives an additional parameter
- * that must be used in this callback.
- * 3. When the start() method returns success, the upper half driver
- * will "sleep" until the pwm_expired method is called.
- * 4. When the lower half detects that the pulse count has expired
- * (probably through an interrupt), it must call the pwm_expired
- * interface using the handle that was previously passed to the
- * start() method
- *
- * Input parameters:
- * handle - This is the handle that was provided to the lower-half
- * start() method.
- *
- * Returned Value:
- * None
- *
- * Assumptions:
- * This function may be called from an interrupt handler.
- *
- ****************************************************************************/
-
-#ifdef CONFIG_PWM_PULSECOUNT
-void pwm_expired(FAR void *handle)
-{
- FAR struct pwm_upperhalf_s *upper = (FAR struct pwm_upperhalf_s *)handle;
-
- pwmllvdbg("started: %d waiting: %d\n", upper->started, upper->waiting);
-
- /* Make sure that the PWM is started */
-
- if (upper->started)
- {
- /* Is there a thread waiting for the pulse train to complete? */
-
- if (upper->waiting)
- {
- /* Yes.. clear the waiting flag and awakened the waiting thread */
-
- upper->waiting = false;
- sem_post(&upper->waitsem);
- }
-
- /* The PWM is now stopped */
-
- upper->started = false;
- }
-}
-#endif
-
-#endif /* CONFIG_PWM */
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