diff options
Diffstat (limited to 'usr.sbin/pwm')
| -rw-r--r-- | usr.sbin/pwm/Makefile | 4 | ||||
| -rw-r--r-- | usr.sbin/pwm/pwm.8 | 123 | ||||
| -rw-r--r-- | usr.sbin/pwm/pwm.c | 215 |
3 files changed, 342 insertions, 0 deletions
diff --git a/usr.sbin/pwm/Makefile b/usr.sbin/pwm/Makefile new file mode 100644 index 000000000000..17ec1dbfbb4a --- /dev/null +++ b/usr.sbin/pwm/Makefile @@ -0,0 +1,4 @@ +PROG= pwm +MAN= pwm.8 + +.include <bsd.prog.mk> diff --git a/usr.sbin/pwm/pwm.8 b/usr.sbin/pwm/pwm.8 new file mode 100644 index 000000000000..359cdac52822 --- /dev/null +++ b/usr.sbin/pwm/pwm.8 @@ -0,0 +1,123 @@ +.\" 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 DEVELOPERS ``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 DEVELOPERS 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. +.\" +.Dd June 17, 2019 +.Dt PWM 8 +.Os +.Sh NAME +.Nm pwm +.Nd configure PWM (Pulse Width Modulation) hardware +.Sh SYNOPSIS +.Nm +.Op Fl f Ar device +.Fl C +.Nm +.Op Fl f Ar device +.Op Fl D | Fl E +.Op Fl I +.Op Fl p Ar period +.Op Fl d Ar duty +.Sh DESCRIPTION +The +.Nm +utility can be used to configure pwm hardware. +.Nm +uses a +.Xr pwmc 4 +device to communicate with the hardware. +Some PWM hardware supports multiple output channels within a single +controller block; each +.Xr pwmc 4 +instance controls a single PWM channel. +.Pp +.Xr pwmc 4 +devices are named +.Pa /dev/pwm/pwmcX.Y , +where +.Va X +is the controller unit number and +.Va Y +is the channel number within that unit. +.Pp +The options are as follows: +.Bl -tag -width "-f device" +.It Fl f Ar device +Device to operate on. +If not specified, +.Pa /dev/pwm/pwmc0.0 +is used. +If an unqualified name is provided, +.Pa /dev/pwm +is automatically prepended. +.It Fl C +Show the configuration of the PWM channel. +.It Fl D +Disable the PWM channel. +.It Fl d Ar duty +Configure the duty cycle (in nanoseconds or percentage) of the PWM channel. +Duty is the portion of the +.Ar period +during which the signal is asserted. +.It Fl E +Enable the PWM channel. +.It Fl p Ar period +Configure the period (in nanoseconds) of the PWM channel. +.It Fl I +Invert PWM signal polarity +.El +.Sh EXAMPLES +.Bl -bullet +.It +Show the configuration of the PWM channel: +.Bd -literal +pwm -f /dev/pwm/pwmc0.1 -C +.Ed +.It +Configure a 50000 ns period and a 25000 ns duty cycle +and enable the channel: +.Bd -literal +pwm -f pwmc1.1 -E -p 50000 -d 25000 +.Ed +.It +Configure a 50% duty cycle on the device and channel which +were configured in +.Xr pwmc 4 +to have the label +.Pa backlight : +.Bd -literal +pwm -f backlight -d 50% +.Ed +.El +.Sh SEE ALSO +.Xr pwm 9 , +.Xr pwmbus 9 +.Sh HISTORY +The +.Nm +utility appeared in +.Fx 13.0 . +.Sh AUTHORS +.An -nosplit +The +.Nm +utility and this manual page were written by +.An Emmanuel Vadot Aq Mt manu@FreeBSD.org . diff --git a/usr.sbin/pwm/pwm.c b/usr.sbin/pwm/pwm.c new file mode 100644 index 000000000000..d7bbbad6c173 --- /dev/null +++ b/usr.sbin/pwm/pwm.c @@ -0,0 +1,215 @@ +/*- + * SPDX-License-Identifier: BSD-2-Clause + * + * 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. + */ + +#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 +#define PWM_INVERTED 0x0020 + +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] [-I] [-p period] [-d duty[%%]]\n"); + exit(1); +} + +int +main(int argc, char *argv[]) +{ + struct pwm_state state; + int fd; + u_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:EDCIp: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 'I': + if (action & PWM_SHOW_CONFIG) + usage(); + action |= PWM_INVERTED; + break; + case 'p': + if (action & PWM_SHOW_CONFIG) + usage(); + action |= PWM_PERIOD; + period = strtoul(optarg, NULL, 10); + break; + case 'd': + if (action & PWM_SHOW_CONFIG) + usage(); + action |= PWM_DUTY; + duty = strtoul(optarg, &percent, 10); + if (*percent == '%') { + if (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\ninverted:%d\n", + state.period, + state.duty, + state.enable, + state.flags & PWM_POLARITY_INVERTED); + } 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_INVERTED) + state.flags |= PWM_POLARITY_INVERTED; + else + state.flags &= ~PWM_POLARITY_INVERTED; + if (action & PWM_DUTY) { + if (*percent != '\0') + state.duty = (uint64_t)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); +} |