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+/****************************************************************************
+ * examples/pwm/pwm_main.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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <sys/ioctl.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/pwm.h>
+
+#include "pwm.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+struct pwm_state_s
+{
+ bool initialized;
+ FAR char *devpath;
+ uint8_t duty;
+ uint32_t freq;
+#ifdef CONFIG_PWM_PULSECOUNT
+ uint32_t count;
+#endif
+ int duration;
+};
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static struct pwm_state_s g_pwmstate;
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: pwm_devpath
+ ****************************************************************************/
+
+static void pwm_devpath(FAR struct pwm_state_s *pwm, FAR const char *devpath)
+{
+ /* Get rid of any old device path */
+
+ if (pwm->devpath)
+ {
+ free(pwm->devpath);
+ }
+
+ /* Then set-up the new device path by copying the string */
+
+ pwm->devpath = strdup(devpath);
+}
+
+/****************************************************************************
+ * Name: pwm_help
+ ****************************************************************************/
+
+static void pwm_help(FAR struct pwm_state_s *pwm)
+{
+ message("Usage: pwm [OPTIONS]\n");
+ message("\nArguments are \"sticky\". For example, once the PWM frequency is\n");
+ message("specified, that frequency will be re-used until it is changed.\n");
+ message("\n\"sticky\" OPTIONS include:\n");
+ message(" [-p devpath] selects the PWM device. "
+ "Default: %s Current: %s\n",
+ CONFIG_EXAMPLES_PWM_DEVPATH, pwm->devpath ? pwm->devpath : "NONE");
+ message(" [-f addr] selects the pulse frequency. "
+ "Default: %d Hz Current: %d Hz\n",
+ CONFIG_EXAMPLES_PWM_FREQUENCY, pwm->freq);
+ message(" [-d duty] selcts the pulse duty as a percentage. "
+ "Default: %d %% Current: %d %%\n",
+ CONFIG_EXAMPLES_PWM_DUTYPCT, pwm->duty);
+#ifdef CONFIG_PWM_PULSECOUNT
+ message(" [-n count] selects the pulse count. "
+ "Default: %d Current: %d\n",
+ CONFIG_EXAMPLES_PWM_COUNT, pwm->count);
+#endif
+ message(" [-t duration] is the duration of the pulse train in seconds. "
+ "Default: %d Current: %d\n",
+ CONFIG_EXAMPLES_PWM_DURATION, pwm->duration);
+ message(" [-h] shows this message and exits\n");
+}
+
+/****************************************************************************
+ * Name: arg_string
+ ****************************************************************************/
+
+static int arg_string(FAR char **arg, FAR char **value)
+{
+ FAR char *ptr = *arg;
+
+ if (ptr[2] == '\0')
+ {
+ *value = arg[1];
+ return 2;
+ }
+ else
+ {
+ *value = &ptr[2];
+ return 1;
+ }
+}
+
+/****************************************************************************
+ * Name: arg_decimal
+ ****************************************************************************/
+
+static int arg_decimal(FAR char **arg, FAR long *value)
+{
+ FAR char *string;
+ int ret;
+
+ ret = arg_string(arg, &string);
+ *value = strtol(string, NULL, 10);
+ return ret;
+}
+
+/****************************************************************************
+ * Name: parse_args
+ ****************************************************************************/
+
+static void parse_args(FAR struct pwm_state_s *pwm, int argc, FAR char **argv)
+{
+ FAR char *ptr;
+ FAR char *str;
+ long value;
+ int index;
+ int nargs;
+
+ for (index = 1; index < argc; )
+ {
+ ptr = argv[index];
+ if (ptr[0] != '-')
+ {
+ message("Invalid options format: %s\n", ptr);
+ exit(0);
+ }
+
+ switch (ptr[1])
+ {
+ case 'f':
+ nargs = arg_decimal(&argv[index], &value);
+ if (value < 1)
+ {
+ message("Frequency out of range: %ld\n", value);
+ exit(1);
+ }
+
+ pwm->freq = (uint32_t)value;
+ index += nargs;
+ break;
+
+ case 'd':
+ nargs = arg_decimal(&argv[index], &value);
+ if (value < 1 || value > 99)
+ {
+ message("Duty out of range: %ld\n", value);
+ exit(1);
+ }
+
+ pwm->duty = (uint8_t)value;
+ index += nargs;
+ break;
+
+#ifdef CONFIG_PWM_PULSECOUNT
+ case 'n':
+ nargs = arg_decimal(&argv[index], &value);
+ if (value < 0)
+ {
+ message("Count must be non-negative: %ld\n", value);
+ exit(1);
+ }
+
+ pwm->count = (uint32_t)value;
+ index += nargs;
+ break;
+
+#endif
+ case 'p':
+ nargs = arg_string(&argv[index], &str);
+ pwm_devpath(pwm, str);
+ index += nargs;
+ break;
+
+ case 't':
+ nargs = arg_decimal(&argv[index], &value);
+ if (value < 1 || value > INT_MAX)
+ {
+ message("Duration out of range: %ld\n", value);
+ exit(1);
+ }
+
+ pwm->duration = (int)value;
+ index += nargs;
+ break;
+
+ case 'h':
+ pwm_help(pwm);
+ exit(0);
+
+ default:
+ message("Unsupported option: %s\n", ptr);
+ pwm_help(pwm);
+ exit(1);
+ }
+ }
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: user_start/pwm_main
+ ****************************************************************************/
+
+int pwm_main(int argc, char *argv[])
+{
+ struct pwm_info_s info;
+ int fd;
+ int ret;
+
+ /* Initialize the state data */
+
+ if (!g_pwmstate.initialized)
+ {
+ g_pwmstate.duty = CONFIG_EXAMPLES_PWM_DUTYPCT;
+ g_pwmstate.freq = CONFIG_EXAMPLES_PWM_FREQUENCY;
+ g_pwmstate.duration = CONFIG_EXAMPLES_PWM_DURATION;
+#ifdef CONFIG_PWM_PULSECOUNT
+ g_pwmstate.count = CONFIG_EXAMPLES_PWM_COUNT;
+#endif
+ g_pwmstate.initialized = true;
+ }
+
+ /* Parse the command line */
+
+ parse_args(&g_pwmstate, argc, argv);
+
+ /* Has a device been assigned? */
+
+ if (!g_pwmstate.devpath)
+ {
+ /* No.. use the default device */
+
+ pwm_devpath(&g_pwmstate, CONFIG_EXAMPLES_PWM_DEVPATH);
+ }
+
+ /* Initialization of the PWM hardware is performed by logic external to
+ * this test.
+ */
+
+ ret = pwm_devinit();
+ if (ret != OK)
+ {
+ message("pwm_main: pwm_devinit failed: %d\n", ret);
+ goto errout;
+ }
+
+ /* Open the PWM device for reading */
+
+ fd = open(g_pwmstate.devpath, O_RDONLY);
+ if (fd < 0)
+ {
+ message("pwm_main: open %s failed: %d\n", g_pwmstate.devpath, errno);
+ goto errout;
+ }
+
+ /* Configure the characteristics of the pulse train */
+
+ info.frequency = g_pwmstate.freq;
+ info.duty = ((uint32_t)g_pwmstate.duty << 16) / 100;
+#ifdef CONFIG_PWM_PULSECOUNT
+ info.count = g_pwmstate.count;
+
+ message("pwm_main: starting output with frequency: %d duty: %08x count: %d\n",
+ info.frequency, info.duty, info.count);
+
+#else
+ message("pwm_main: starting output with frequency: %d duty: %08x\n",
+ info.frequency, info.duty);
+
+#endif
+
+ ret = ioctl(fd, PWMIOC_SETCHARACTERISTICS, (unsigned long)((uintptr_t)&info));
+ if (ret < 0)
+ {
+ message("pwm_main: ioctl(PWMIOC_SETCHARACTERISTICS) failed: %d\n", errno);
+ goto errout_with_dev;
+ }
+
+ /* Then start the pulse train. Since the driver was opened in blocking
+ * mode, this call will block if the count value is greater than zero.
+ */
+
+ ret = ioctl(fd, PWMIOC_START, 0);
+ if (ret < 0)
+ {
+ message("pwm_main: ioctl(PWMIOC_START) failed: %d\n", errno);
+ goto errout_with_dev;
+ }
+
+ /* It a non-zero count was not specified, then wait for the selected
+ * duration, then stop the PWM output.
+ */
+
+#ifdef CONFIG_PWM_PULSECOUNT
+ if (info.count == 0)
+#endif
+ {
+ /* Wait for the specified duration */
+
+ sleep(g_pwmstate.duration);
+
+ /* Then stop the pulse train */
+
+ message("pwm_main: stopping output\n", info.frequency, info.duty);
+
+ ret = ioctl(fd, PWMIOC_STOP, 0);
+ if (ret < 0)
+ {
+ message("pwm_main: ioctl(PWMIOC_STOP) failed: %d\n", errno);
+ goto errout_with_dev;
+ }
+ }
+
+ close(fd);
+ msgflush();
+ return OK;
+
+errout_with_dev:
+ close(fd);
+errout:
+ msgflush();
+ return ERROR;
+}