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Diffstat (limited to 'apps/examples/pwm/pwm_main.c')
-rw-r--r-- | apps/examples/pwm/pwm_main.c | 394 |
1 files changed, 394 insertions, 0 deletions
diff --git a/apps/examples/pwm/pwm_main.c b/apps/examples/pwm/pwm_main.c new file mode 100644 index 000000000..64c5dfb2c --- /dev/null +++ b/apps/examples/pwm/pwm_main.c @@ -0,0 +1,394 @@ +/**************************************************************************** + * 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; +} |