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diff --git a/man4/lirc.4 b/man4/lirc.4 deleted file mode 100644 index 4bd356d2e..000000000 --- a/man4/lirc.4 +++ /dev/null @@ -1,422 +0,0 @@ -.\" Copyright (c) 2015-2016, Alec Leamas -.\" Copyright (c) 2018, Sean Young <sean@mess.org> -.\" -.\" SPDX-License-Identifier: GPL-2.0-or-later -.TH lirc 4 (date) "Linux man-pages (unreleased)" -.SH NAME -lirc \- lirc devices -.SH DESCRIPTION -The -.I /dev/lirc* -character devices provide a low-level -bidirectional interface to infra-red (IR) remotes. -Most of these devices can receive, and some can send. -When receiving or sending data, the driver works in two different modes -depending on the underlying hardware. -.PP -Some hardware (typically TV-cards) decodes the IR signal internally -and provides decoded button presses as scancode values. -Drivers for this kind of hardware work in -.B LIRC_MODE_SCANCODE -mode. -Such hardware usually does not support sending IR signals. -Furthermore, such hardware can only decode a limited set of IR protocols, -usually only the protocol of the specific remote which is -bundled with, for example, a TV-card. -.PP -Other hardware provides a stream of pulse/space durations. -Such drivers work in -.B LIRC_MODE_MODE2 -mode. -Such hardware can be used with (almost) any kind of remote. -This type of hardware can also be used in -.B LIRC_MODE_SCANCODE -mode, in which case the kernel IR decoders will decode the IR. -These decoders can be written in extended BPF (see -.BR bpf (2)) -and attached to the -.B lirc -device. -Sometimes, this kind of hardware also supports -sending IR data. -.PP -The \fBLIRC_GET_FEATURES\fR ioctl (see below) allows probing for whether -receiving and sending is supported, and in which modes, amongst other -features. -.\" -.SS Reading input with the LIRC_MODE_MODE2 mode -In the \fBLIRC_MODE_MODE2 mode\fR, the data returned by -.BR read (2) -provides 32-bit values representing a space or a pulse duration. -The time of the duration (microseconds) is encoded in the lower 24 bits. -Pulse (also known as flash) -indicates a duration of infrared light being detected, -and space (also known as gap) indicates a duration with no infrared. -If the duration of space exceeds the inactivity timeout, -a special timeout package is delivered, -which marks the end of a message. -The upper 8 bits indicate the type of package: -.TP 4 -.B LIRC_MODE2_SPACE -Value reflects a space duration (microseconds). -.TP 4 -.B LIRC_MODE2_PULSE -Value reflects a pulse duration (microseconds). -.TP 4 -.B LIRC_MODE2_FREQUENCY -Value reflects a frequency (Hz); see the -.B LIRC_SET_MEASURE_CARRIER_MODE -ioctl. -.TP 4 -.B LIRC_MODE2_TIMEOUT -Value reflects a space duration (microseconds). -The package reflects a timeout; see the -.B LIRC_SET_REC_TIMEOUT_REPORTS -ioctl. -.\" -.TP 4 -.B LIRC_MODE2_OVERFLOW -The IR receiver encountered an overflow, -and as a result data is missing -(since Linux 5.18). -.SS Reading input with the LIRC_MODE_SCANCODE mode -In the \fBLIRC_MODE_SCANCODE\fR -mode, the data returned by -.BR read (2) -reflects decoded button presses, in the struct \fIlirc_scancode\fR. -The scancode is stored in the \fIscancode\fR field, and the IR protocol -is stored in \fIrc_proto\fR. -This field has one the values of the \fIenum rc_proto\fR. -.\" -.SS Writing output with the LIRC_MODE_PULSE mode -The data written to the character device using -.BR write (2) -is a pulse/space sequence of integer values. -Pulses and spaces are only marked implicitly by their position. -The data must start and end with a pulse, thus it must always include -an odd number of samples. -The -.BR write (2) -function blocks until the data has been transmitted by the -hardware. -If more data is provided than the hardware can send, the -.BR write (2) -call fails with the error -.BR EINVAL . -.SS Writing output with the LIRC_MODE_SCANCODE mode -The data written to the character devices must be a single struct -\fIlirc_scancode\fR. -The \fIscancode\fR and \fIrc_proto\fR fields must -filled in, all other fields must be 0. -The kernel IR encoders will -convert the scancode to pulses and spaces. -The protocol or scancode is invalid, or the -.B lirc -device cannot transmit. -.SH IOCTL COMMANDS -.nf -#include <linux/lirc.h> /* But see BUGS */ -\& -int ioctl(int fd, int cmd, int *val); -.fi -.PP -The following -.BR ioctl (2) -operations are provided by the -.B lirc -character device to probe or change specific -.B lirc -hardware settings. -.SS Always Supported Commands -\fI/dev/lirc*\fR devices always support the following commands: -.TP 4 -.BR LIRC_GET_FEATURES " (\fIvoid\fP)" -Returns a bit mask of combined features bits; see FEATURES. -.PP -If a device returns an error code for -.BR LIRC_GET_FEATURES , -it is safe to assume it is not a -.B lirc -device. -.\" -.SS Optional Commands -Some -.B lirc -devices support the commands listed below. -Unless otherwise stated, these fail with the error \fBENOTTY\fR if the -operation isn't supported, or with the error \fBEINVAL\fR if the operation -failed, or invalid arguments were provided. -If a driver does not announce support of certain features, invoking -the corresponding ioctls will fail with the error -.BR ENOTTY . -.TP -.BR LIRC_GET_REC_MODE " (\fIvoid\fP)" -If the -.B lirc -device has no receiver, this operation fails with the error -.BR ENOTTY . -Otherwise, it returns the receive mode, which will be one of: -.RS -.TP -.B LIRC_MODE_MODE2 -The driver returns a sequence of pulse/space durations. -.TP -.B LIRC_MODE_SCANCODE -The driver returns struct -.I lirc_scancode -values, each of which represents -a decoded button press. -.RE -.TP -.BR LIRC_SET_REC_MODE " (\fIint\fP)" -Set the receive mode. -.I val -is either -.B LIRC_MODE_SCANCODE -or -.BR LIRC_MODE_MODE2 . -If the -.B lirc -device has no receiver, this operation fails with the error -.B ENOTTY. -.TP -.BR LIRC_GET_SEND_MODE " (\fIvoid\fP)" -Return the send mode. -.B LIRC_MODE_PULSE -or -.B LIRC_MODE_SCANCODE -is supported. -If the -.B lirc -device cannot send, this operation fails with the error -.B ENOTTY. -.TP -.BR LIRC_SET_SEND_MODE " (\fIint\fP)" -Set the send mode. -.I val -is either -.B LIRC_MODE_SCANCODE -or -.BR LIRC_MODE_PULSE . -If the -.B lirc -device cannot send, this operation fails with the error -.BR ENOTTY . -.TP -.BR LIRC_SET_SEND_CARRIER " (\fIint\fP)" -Set the modulation frequency. -The argument is the frequency (Hz). -.TP -.BR LIRC_SET_SEND_DUTY_CYCLE " (\fIint\fP)" -Set the carrier duty cycle. -.I val -is a number in the range [0,100] which -describes the pulse width as a percentage of the total cycle. -Currently, no special meaning is defined for 0 or 100, but the values -are reserved for future use. -.TP -.BR LIRC_GET_MIN_TIMEOUT " (\fIvoid\fP)", " "\ -LIRC_GET_MAX_TIMEOUT " (\fIvoid\fP)" -Some devices have internal timers that can be used to detect when -there has been no IR activity for a long time. -This can help -.BR lircd (8) -in detecting that an IR signal is finished and can speed up the -decoding process. -These operations -return integer values with the minimum/maximum timeout that can be -set (microseconds). -Some devices have a fixed timeout. -For such drivers, -.B LIRC_GET_MIN_TIMEOUT -and -.B LIRC_GET_MAX_TIMEOUT -will fail with the error -.BR ENOTTY . -.TP -.BR LIRC_SET_REC_TIMEOUT " (\fIint\fP)" -Set the integer value for IR inactivity timeout (microseconds). -To be accepted, the value must be within the limits defined by -.B LIRC_GET_MIN_TIMEOUT -and -.BR LIRC_GET_MAX_TIMEOUT . -A value of 0 (if supported by the hardware) disables all hardware -timeouts and data should be reported as soon as possible. -If the exact value cannot be set, then the next possible value -.I greater -than the given value should be set. -.TP -.BR LIRC_GET_REC_TIMEOUT " (\fIvoid\fP)" -Return the current inactivity timeout (microseconds). -Available since Linux 4.18. -.TP -.BR LIRC_SET_REC_TIMEOUT_REPORTS " (\fIint\fP)" -Enable -.RI ( val -is 1) or disable -.RI ( val -is 0) timeout packages in -.BR LIRC_MODE_MODE2 . -The behavior of this operation has varied across kernel versions: -.RS -.IP \[bu] 3 -Since Linux 5.17: -timeout packages are always enabled and this ioctl is a no-op. -.IP \[bu] -Since Linux 4.16: -timeout packages are enabled by default. -Each time the -.B lirc -device is opened, the -.B LIRC_SET_REC_TIMEOUT -operation can be used to disable (and, if desired, to later re-enable) -the timeout on the file descriptor. -.IP \[bu] -In Linux 4.15 and earlier: -timeout packages are disabled by default, and enabling them (via -.BR LIRC_SET_REC_TIMEOUT ) -on any file descriptor associated with the -.B lirc -device has the effect of enabling timeouts for all file descriptors -referring to that device (until timeouts are disabled again). -.RE -.TP -.BR LIRC_SET_REC_CARRIER " (\fIint\fP)" -Set the upper bound of the receive carrier frequency (Hz). -See -.BR LIRC_SET_REC_CARRIER_RANGE . -.TP -.BR LIRC_SET_REC_CARRIER_RANGE " (\fIint\fP)" -Sets the lower bound of the receive carrier frequency (Hz). -For this to take affect, first set the lower bound using the -.B LIRC_SET_REC_CARRIER_RANGE -ioctl, and then the upper bound using the -.B LIRC_SET_REC_CARRIER -ioctl. -.TP -.BR LIRC_SET_MEASURE_CARRIER_MODE " (\fIint\fP)" -Enable -.RI ( val -is 1) or disable -.RI ( val -is 0) the measure mode. -If enabled, from the next key press on, the driver will send -.B LIRC_MODE2_FREQUENCY -packets. -By default, this should be turned off. -.TP -.BR LIRC_GET_REC_RESOLUTION " (\fIvoid\fP)" -Return the driver resolution (microseconds). -.TP -.BR LIRC_SET_TRANSMITTER_MASK " (\fIint\fP)" -Enable the set of transmitters specified in -.IR val , -which contains a bit mask where each enabled transmitter is a 1. -The first transmitter is encoded by the least significant bit, and so on. -When an invalid bit mask is given, for example a bit is set even -though the device does not have so many transmitters, -this operation returns the -number of available transmitters and does nothing otherwise. -.TP -.BR LIRC_SET_WIDEBAND_RECEIVER " (\fIint\fP)" -Some devices are equipped with a special wide band receiver which is -intended to be used to learn the output of an existing remote. -This ioctl can be used to enable -.RI ( val -equals 1) or disable -.RI ( val -equals 0) this functionality. -This might be useful for devices that otherwise have narrow band -receivers that prevent them to be used with certain remotes. -Wide band receivers may also be more precise. -On the other hand, their disadvantage usually is reduced range of -reception. -.IP -Note: wide band receiver may be implicitly enabled if you enable -carrier reports. -In that case, it will be disabled as soon as you disable carrier reports. -Trying to disable a wide band receiver while carrier reports are active -will do nothing. -.\" -.SH FEATURES -the -.B LIRC_GET_FEATURES -ioctl returns a bit mask describing features of the driver. -The following bits may be returned in the mask: -.TP -.B LIRC_CAN_REC_MODE2 -The driver is capable of receiving using -.BR LIRC_MODE_MODE2 . -.TP -.B LIRC_CAN_REC_SCANCODE -The driver is capable of receiving using -.BR LIRC_MODE_SCANCODE . -.TP -.B LIRC_CAN_SET_SEND_CARRIER -The driver supports changing the modulation frequency using -.BR LIRC_SET_SEND_CARRIER . -.TP -.B LIRC_CAN_SET_SEND_DUTY_CYCLE -The driver supports changing the duty cycle using -.BR LIRC_SET_SEND_DUTY_CYCLE . -.TP -.B LIRC_CAN_SET_TRANSMITTER_MASK -The driver supports changing the active transmitter(s) using -.BR LIRC_SET_TRANSMITTER_MASK . -.TP -.B LIRC_CAN_SET_REC_CARRIER -The driver supports setting the receive carrier frequency using -.BR LIRC_SET_REC_CARRIER . -Any -.B lirc -device since the drivers were merged in Linux 2.6.36 -must have -.B LIRC_CAN_SET_REC_CARRIER_RANGE -set if -.B LIRC_CAN_SET_REC_CARRIER -feature is set. -.TP -.B LIRC_CAN_SET_REC_CARRIER_RANGE -The driver supports -.BR LIRC_SET_REC_CARRIER_RANGE . -The lower bound of the carrier must first be set using the -.B LIRC_SET_REC_CARRIER_RANGE -ioctl, before using the -.B LIRC_SET_REC_CARRIER -ioctl to set the upper bound. -.TP -.B LIRC_CAN_GET_REC_RESOLUTION -The driver supports -.BR LIRC_GET_REC_RESOLUTION . -.TP -.B LIRC_CAN_SET_REC_TIMEOUT -The driver supports -.BR LIRC_SET_REC_TIMEOUT . -.TP -.B LIRC_CAN_MEASURE_CARRIER -The driver supports measuring of the modulation frequency using -.BR LIRC_SET_MEASURE_CARRIER_MODE . -.TP -.B LIRC_CAN_USE_WIDEBAND_RECEIVER -The driver supports learning mode using -.BR LIRC_SET_WIDEBAND_RECEIVER . -.TP -.B LIRC_CAN_SEND_PULSE -The driver supports sending using -.B LIRC_MODE_PULSE -or -.B LIRC_MODE_SCANCODE -.\" -.SH BUGS -Using these devices requires the kernel source header file -.IR lirc.h . -This file is not available before Linux 4.6. -Users of older kernels could use the file bundled in -.UR http://www.lirc.org -.UE . -.\" -.SH SEE ALSO -\fBir\-ctl\fP(1), \fBlircd\fP(8),\ \fBbpf\fP(2) -.PP -.UR https://www.kernel.org/\:doc/\:html/\:latest/\:userspace\-api/\:media/\:rc/\:lirc\-dev.html -.UE |