freebsd-dev/usr.sbin/pwm/pwm.c
Emmanuel Vadot e213223c9b Remove "all rights reserved" from copyright for the file I own.
Some of the files have both me and Jared McNeill and he gave me
permission to remove it from his files too.
2019-12-03 21:00:45 +00:00

208 lines
4.9 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2018 Emmanuel Vadot <manu@FreeBSD.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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
#include <sys/types.h>
#include <sys/ioctl.h>
#include <stdbool.h>
#include <sys/capsicum.h>
#include <dev/pwm/pwmc.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <capsicum_helpers.h>
#define PWM_ENABLE 0x0001
#define PWM_DISABLE 0x0002
#define PWM_SHOW_CONFIG 0x0004
#define PWM_PERIOD 0x0008
#define PWM_DUTY 0x0010
static char device_name[PATH_MAX] = "/dev/pwm/pwmc0.0";
static void
set_device_name(const char *name)
{
if (name[0] == '/')
strlcpy(device_name, name, sizeof(device_name));
else
snprintf(device_name, sizeof(device_name), "/dev/pwm/%s", name);
}
static void
usage(void)
{
fprintf(stderr, "Usage:\n");
fprintf(stderr, "\tpwm [-f dev] -C\n");
fprintf(stderr, "\tpwm [-f dev] [-D | -E] [-p period] [-d duty[%%]]\n");
exit(1);
}
int
main(int argc, char *argv[])
{
struct pwm_state state;
int fd;
int period, duty;
int action, ch;
cap_rights_t right_ioctl;
const unsigned long pwm_ioctls[] = {PWMGETSTATE, PWMSETSTATE};
char *percent;
bool setname;
action = 0;
setname = false;
fd = -1;
period = duty = -1;
while ((ch = getopt(argc, argv, "f:EDCp:d:")) != -1) {
switch (ch) {
case 'E':
if (action & (PWM_DISABLE | PWM_SHOW_CONFIG))
usage();
action |= PWM_ENABLE;
break;
case 'D':
if (action & (PWM_ENABLE | PWM_SHOW_CONFIG))
usage();
action |= PWM_DISABLE;
break;
case 'C':
if (action)
usage();
action = PWM_SHOW_CONFIG;
break;
case 'p':
if (action & PWM_SHOW_CONFIG)
usage();
action |= PWM_PERIOD;
period = strtol(optarg, NULL, 10);
break;
case 'd':
if (action & PWM_SHOW_CONFIG)
usage();
action |= PWM_DUTY;
duty = strtol(optarg, &percent, 10);
if (*percent == '%') {
if (duty < 0 || duty > 100) {
fprintf(stderr,
"Invalid duty percentage\n");
usage();
}
} else if (*percent != '\0')
usage();
break;
case 'f':
setname = true;
set_device_name(optarg);
break;
case '?':
usage();
break;
}
}
if (action == 0)
usage();
if ((fd = open(device_name, O_RDWR)) == -1) {
fprintf(stderr, "pwm: cannot open %s: %s\n",
device_name, strerror(errno));
if (setname)
exit(1);
else
usage();
}
if (caph_limit_stdio() < 0) {
fprintf(stderr, "can't limit stdio rights");
goto fail;
}
caph_cache_catpages();
cap_rights_init(&right_ioctl, CAP_IOCTL);
if (caph_rights_limit(fd, &right_ioctl) < 0) {
fprintf(stderr, "cap_right_limit() failed\n");
goto fail;
}
if (caph_ioctls_limit(fd, pwm_ioctls, nitems(pwm_ioctls)) < 0) {
fprintf(stderr, "caph_ioctls_limit() failed\n");
goto fail;
}
if (caph_enter() < 0) {
fprintf(stderr, "failed to enter capability mode\n");
goto fail;
}
/* Fill the common args */
if (ioctl(fd, PWMGETSTATE, &state) == -1) {
fprintf(stderr, "Cannot get current state of the pwm controller\n");
goto fail;
}
if (action == PWM_SHOW_CONFIG) {
printf("period: %u\nduty: %u\nenabled:%d\n",
state.period,
state.duty,
state.enable);
goto fail;
} else {
if (action & PWM_ENABLE)
state.enable = true;
if (action & PWM_DISABLE)
state.enable = false;
if (action & PWM_PERIOD)
state.period = period;
if (action & PWM_DUTY) {
if (*percent != '\0')
state.duty = state.period * duty / 100;
else
state.duty = duty;
}
if (ioctl(fd, PWMSETSTATE, &state) == -1) {
fprintf(stderr,
"Cannot configure the pwm controller\n");
goto fail;
}
}
close(fd);
return (0);
fail:
close(fd);
return (1);
}