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diff --git a/Documentation/DocBook/media/v4l/lirc_device_interface.xml b/Documentation/DocBook/media/v4l/lirc_device_interface.xml deleted file mode 100644 index 34cada2ca710..000000000000 --- a/Documentation/DocBook/media/v4l/lirc_device_interface.xml +++ /dev/null @@ -1,255 +0,0 @@ -<section id="lirc_dev"> -<title>LIRC Device Interface</title> - - -<section id="lirc_dev_intro"> -<title>Introduction</title> - -<para>The LIRC device interface is a bi-directional interface for -transporting raw IR data between userspace and kernelspace. Fundamentally, -it is just a chardev (/dev/lircX, for X = 0, 1, 2, ...), with a number -of standard struct file_operations defined on it. With respect to -transporting raw IR data to and fro, the essential fops are read, write -and ioctl.</para> - -<para>Example dmesg output upon a driver registering w/LIRC:</para> - <blockquote> - <para>$ dmesg |grep lirc_dev</para> - <para>lirc_dev: IR Remote Control driver registered, major 248</para> - <para>rc rc0: lirc_dev: driver ir-lirc-codec (mceusb) registered at minor = 0</para> - </blockquote> - -<para>What you should see for a chardev:</para> - <blockquote> - <para>$ ls -l /dev/lirc*</para> - <para>crw-rw---- 1 root root 248, 0 Jul 2 22:20 /dev/lirc0</para> - </blockquote> -</section> - -<section id="lirc_read"> -<title>LIRC read fop</title> - -<para>The lircd userspace daemon reads raw IR data from the LIRC chardev. The -exact format of the data depends on what modes a driver supports, and what -mode has been selected. lircd obtains supported modes and sets the active mode -via the ioctl interface, detailed at <xref linkend="lirc_ioctl"/>. The generally -preferred mode is LIRC_MODE_MODE2, in which packets containing an int value -describing an IR signal are read from the chardev.</para> - -<para>See also <ulink url="http://www.lirc.org/html/technical.html">http://www.lirc.org/html/technical.html</ulink> for more info.</para> -</section> - -<section id="lirc_write"> -<title>LIRC write fop</title> - -<para>The data written to the chardev 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, therefore, the data must always include -an uneven number of samples. The write function must block until the data has -been transmitted by the hardware. If more data is provided than the hardware -can send, the driver returns EINVAL.</para> - -</section> - -<section id="lirc_ioctl"> -<title>LIRC ioctl fop</title> - -<para>The LIRC device's ioctl definition is bound by the ioctl function -definition of struct file_operations, leaving us with an unsigned int -for the ioctl command and an unsigned long for the arg. For the purposes -of ioctl portability across 32-bit and 64-bit, these values are capped -to their 32-bit sizes.</para> - -<para>The following ioctls can be used to change specific hardware settings. -In general each driver should have a default set of settings. The driver -implementation is expected to re-apply the default settings when the device -is closed by user-space, so that every application opening the device can rely -on working with the default settings initially.</para> - -<variablelist> - <varlistentry> - <term>LIRC_GET_FEATURES</term> - <listitem> - <para>Obviously, get the underlying hardware device's features. If a driver - does not announce support of certain features, calling of the corresponding - ioctls is undefined.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_GET_SEND_MODE</term> - <listitem> - <para>Get supported transmit mode. Only LIRC_MODE_PULSE is supported by lircd.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_GET_REC_MODE</term> - <listitem> - <para>Get supported receive modes. Only LIRC_MODE_MODE2 and LIRC_MODE_LIRCCODE - are supported by lircd.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_GET_SEND_CARRIER</term> - <listitem> - <para>Get carrier frequency (in Hz) currently used for transmit.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_GET_REC_CARRIER</term> - <listitem> - <para>Get carrier frequency (in Hz) currently used for IR reception.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_{G,S}ET_{SEND,REC}_DUTY_CYCLE</term> - <listitem> - <para>Get/set the duty cycle (from 0 to 100) of the carrier signal. Currently, - no special meaning is defined for 0 or 100, but this could be used to switch - off carrier generation in the future, so these values should be reserved.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_GET_REC_RESOLUTION</term> - <listitem> - <para>Some receiver have maximum resolution which is defined by internal - sample rate or data format limitations. E.g. it's common that signals can - only be reported in 50 microsecond steps. This integer value is used by - lircd to automatically adjust the aeps tolerance value in the lircd - config file.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_GET_M{IN,AX}_TIMEOUT</term> - <listitem> - <para>Some devices have internal timers that can be used to detect when - there's no IR activity for a long time. This can help lircd in detecting - that a IR signal is finished and can speed up the decoding process. - Returns an integer value with the minimum/maximum timeout that can be - set. Some devices have a fixed timeout, in that case both ioctls will - return the same value even though the timeout cannot be changed.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_GET_M{IN,AX}_FILTER_{PULSE,SPACE}</term> - <listitem> - <para>Some devices are able to filter out spikes in the incoming signal - using given filter rules. These ioctls return the hardware capabilities - that describe the bounds of the possible filters. Filter settings depend - on the IR protocols that are expected. lircd derives the settings from - all protocols definitions found in its config file.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_GET_LENGTH</term> - <listitem> - <para>Retrieves the code length in bits (only for LIRC_MODE_LIRCCODE). - Reads on the device must be done in blocks matching the bit count. - The bit could should be rounded up so that it matches full bytes.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_SET_{SEND,REC}_MODE</term> - <listitem> - <para>Set send/receive mode. Largely obsolete for send, as only - LIRC_MODE_PULSE is supported.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_SET_{SEND,REC}_CARRIER</term> - <listitem> - <para>Set send/receive carrier (in Hz).</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_SET_TRANSMITTER_MASK</term> - <listitem> - <para>This enables the given set of transmitters. The first transmitter - is encoded by the least significant bit, etc. When an invalid bit mask - is given, i.e. a bit is set, even though the device does not have so many - transitters, then this ioctl returns the number of available transitters - and does nothing otherwise.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_SET_REC_TIMEOUT</term> - <listitem> - <para>Sets the integer value for IR inactivity timeout (cf. - LIRC_GET_MIN_TIMEOUT and 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 _greater_ than the given value should be set.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_SET_REC_TIMEOUT_REPORTS</term> - <listitem> - <para>Enable (1) or disable (0) timeout reports in LIRC_MODE_MODE2. By - default, timeout reports should be turned off.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_SET_REC_FILTER_{,PULSE,SPACE}</term> - <listitem> - <para>Pulses/spaces shorter than this are filtered out by hardware. If - filters cannot be set independently for pulse/space, the corresponding - ioctls must return an error and LIRC_SET_REC_FILTER shall be used instead.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_SET_MEASURE_CARRIER_MODE</term> - <listitem> - <para>Enable (1)/disable (0) measure mode. If enabled, from the next key - press on, the driver will send LIRC_MODE2_FREQUENCY packets. By default - this should be turned off.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_SET_REC_{DUTY_CYCLE,CARRIER}_RANGE</term> - <listitem> - <para>To set a range use LIRC_SET_REC_DUTY_CYCLE_RANGE/LIRC_SET_REC_CARRIER_RANGE - with the lower bound first and later LIRC_SET_REC_DUTY_CYCLE/LIRC_SET_REC_CARRIER - with the upper bound.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_NOTIFY_DECODE</term> - <listitem> - <para>This ioctl is called by lircd whenever a successful decoding of an - incoming IR signal could be done. This can be used by supporting hardware - to give visual feedback to the user e.g. by flashing a LED.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_SETUP_{START,END}</term> - <listitem> - <para>Setting of several driver parameters can be optimized by encapsulating - the according ioctl calls with LIRC_SETUP_START/LIRC_SETUP_END. When a - driver receives a LIRC_SETUP_START ioctl it can choose to not commit - further setting changes to the hardware until a LIRC_SETUP_END is received. - But this is open to the driver implementation and every driver must also - handle parameter changes which are not encapsulated by LIRC_SETUP_START - and LIRC_SETUP_END. Drivers can also choose to ignore these ioctls.</para> - </listitem> - </varlistentry> - <varlistentry> - <term>LIRC_SET_WIDEBAND_RECEIVER</term> - <listitem> - <para>Some receivers are equipped with special wide band receiver which is intended - to be used to learn output of existing remote. - Calling that ioctl with (1) will enable it, and with (0) disable it. - This might be useful of receivers that have otherwise narrow band receiver - that prevents them to be used with some remotes. - Wide band receiver might also be more precise - On the other hand its disadvantage it usually reduced range of reception. - Note: wide band receiver might be implictly enabled if you enable - carrier reports. In that case it will be disabled as soon as you disable - carrier reports. Trying to disable wide band receiver while carrier - reports are active will do nothing.</para> - </listitem> - </varlistentry> -</variablelist> -<section id="lirc_dev_errors"> - &return-value; -</section> -</section> -</section> |