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Diffstat (limited to 'Documentation/media/uapi/rc/lirc_ioctl.rst')
| -rw-r--r-- | Documentation/media/uapi/rc/lirc_ioctl.rst | 187 |
1 files changed, 147 insertions, 40 deletions
diff --git a/Documentation/media/uapi/rc/lirc_ioctl.rst b/Documentation/media/uapi/rc/lirc_ioctl.rst index 916d064476f1..c4c34db61a96 100644 --- a/Documentation/media/uapi/rc/lirc_ioctl.rst +++ b/Documentation/media/uapi/rc/lirc_ioctl.rst @@ -2,9 +2,35 @@ .. _lirc_ioctl: -************** -LIRC ioctl fop -************** +************ +LIRC ioctl() +************ + + +Name +==== + +LIRC ioctl - Sends a I/O control command to a LIRC device + +Synopsis +======== + +.. cpp:function:: int ioctl( int fd, int request, struct v4l2_capability *argp ) + + +Arguments +========= + +``fd`` + File descriptor returned by ``open()``. + +``request`` + The type of I/O control that will be used. See table :ref:`lirc-request` + for details. + +``argp`` + Arguments for the I/O control. They're specific to each request. + The LIRC device's ioctl definition is bound by the ioctl function definition of struct file_operations, leaving us with an unsigned int @@ -12,45 +38,79 @@ 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. -The following ioctls can be used to change specific hardware settings. +The 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. -LIRC_GET_FEATURES +.. _lirc-request: + +I/O control requests +==================== + + +.. _LIRC_GET_FEATURES: + +``LIRC_GET_FEATURES`` + 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. -LIRC_GET_SEND_MODE - Get supported transmit mode. Only LIRC_MODE_PULSE is supported by +.. _LIRC_GET_SEND_MODE: + +``LIRC_GET_SEND_MODE`` + + Get supported transmit mode. Only ``LIRC_MODE_PULSE`` is supported by lircd. -LIRC_GET_REC_MODE - Get supported receive modes. Only LIRC_MODE_MODE2 and - LIRC_MODE_LIRCCODE are supported by lircd. +.. _LIRC_GET_REC_MODE: + +``LIRC_GET_REC_MODE`` + + Get supported receive modes. Only ``LIRC_MODE_MODE2`` and + ``LIRC_MODE_LIRCCODE`` are supported by lircd. + +.. _LIRC_GET_SEND_CARRIER: + +``LIRC_GET_SEND_CARRIER`` -LIRC_GET_SEND_CARRIER Get carrier frequency (in Hz) currently used for transmit. -LIRC_GET_REC_CARRIER +.. _LIRC_GET_REC_CARRIER: + +``LIRC_GET_REC_CARRIER`` + Get carrier frequency (in Hz) currently used for IR reception. -LIRC_{G,S}ET_{SEND,REC}_DUTY_CYCLE +.. _LIRC_GET_SEND_DUTY_CYCLE: +.. _LIRC_GET_REC_DUTY_CYCLE: +.. _LIRC_SET_SEND_DUTY_CYCLE: +.. _LIRC_SET_REC_DUTY_CYCLE: + +``LIRC_{G,S}ET_{SEND,REC}_DUTY_CYCLE`` + 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. -LIRC_GET_REC_RESOLUTION +.. _LIRC_GET_REC_RESOLUTION: + +``LIRC_GET_REC_RESOLUTION`` + 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. -LIRC_GET_M{IN,AX}_TIMEOUT +.. _LIRC_GET_MIN_TIMEOUT: +.. _LIRC_GET_MAX_TIMEOUT: + +``LIRC_GET_M{IN,AX}_TIMEOUT`` + 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 @@ -59,7 +119,13 @@ LIRC_GET_M{IN,AX}_TIMEOUT both ioctls will return the same value even though the timeout cannot be changed. -LIRC_GET_M{IN,AX}_FILTER_{PULSE,SPACE} +.. _LIRC_GET_MIN_FILTER_PULSE: +.. _LIRC_GET_MIN_FILTER_PULSE: +.. _LIRC_GET_MAX_FILTER_SPACE: +.. _LIRC_GET_MAX_FILTER_SPACE: + +``LIRC_GET_M{IN,AX}_FILTER_{PULSE,SPACE}`` + 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. @@ -67,72 +133,113 @@ LIRC_GET_M{IN,AX}_FILTER_{PULSE,SPACE} derives the settings from all protocols definitions found in its config file. -LIRC_GET_LENGTH - Retrieves the code length in bits (only for LIRC_MODE_LIRCCODE). +.. _LIRC_GET_LENGTH: + +``LIRC_GET_LENGTH`` + + 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. -LIRC_SET_{SEND,REC}_MODE +.. _LIRC_SET_SEND_MODE: +.. _LIRC_SET_REC_MODE: + +``LIRC_SET_{SEND,REC}_MODE`` + Set send/receive mode. Largely obsolete for send, as only - LIRC_MODE_PULSE is supported. + ``LIRC_MODE_PULSE`` is supported. + +.. _LIRC_SET_SEND_CARRIER: +.. _LIRC_SET_REC_CARRIER: + +``LIRC_SET_{SEND,REC}_CARRIER`` -LIRC_SET_{SEND,REC}_CARRIER Set send/receive carrier (in Hz). -LIRC_SET_TRANSMITTER_MASK +.. _LIRC_SET_TRANSMITTER_MASK: + +``LIRC_SET_TRANSMITTER_MASK`` + 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. -LIRC_SET_REC_TIMEOUT +.. _LIRC_SET_REC_TIMEOUT: + +``LIRC_SET_REC_TIMEOUT`` + Sets the integer value for IR inactivity timeout (cf. - LIRC_GET_MIN_TIMEOUT and LIRC_GET_MAX_TIMEOUT). A value of 0 + ``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. -LIRC_SET_REC_TIMEOUT_REPORTS - Enable (1) or disable (0) timeout reports in LIRC_MODE_MODE2. By +.. _LIRC_SET_REC_TIMEOUT_REPORTS: + +``LIRC_SET_REC_TIMEOUT_REPORTS`` + + Enable (1) or disable (0) timeout reports in ``LIRC_MODE_MODE2.`` By default, timeout reports should be turned off. -LIRC_SET_REC_FILTER_{,PULSE,SPACE} +.. _LIRC_SET_REC_FILTER_PULSE: +.. _LIRC_SET_REC_FILTER_SPACE: + +``LIRC_SET_REC_FILTER_{PULSE,SPACE}`` + 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 + corresponding ioctls must return an error and ``LIRC_SET_REC_FILTER`` shall be used instead. -LIRC_SET_MEASURE_CARRIER_MODE +.. _LIRC_SET_MEASURE_CARRIER_MODE: + +``LIRC_SET_MEASURE_CARRIER_MODE`` + Enable (1)/disable (0) measure mode. If enabled, from the next key - press on, the driver will send LIRC_MODE2_FREQUENCY packets. By + press on, the driver will send ``LIRC_MODE2_FREQUENCY`` packets. By default this should be turned off. -LIRC_SET_REC_{DUTY_CYCLE,CARRIER}_RANGE +.. _LIRC_SET_REC_DUTY_CYCLE_RANGE: +.. _LIRC_SET_REC_CARRIER_RANGE: + +``LIRC_SET_REC_{DUTY_CYCLE,CARRIER}_RANGE`` + To set a range use - LIRC_SET_REC_DUTY_CYCLE_RANGE/LIRC_SET_REC_CARRIER_RANGE + ``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 + ``LIRC_SET_REC_DUTY_CYCLE/LIRC_SET_REC_CARRIER`` with the upper bound. -LIRC_NOTIFY_DECODE +.. _LIRC_NOTIFY_DECODE: + +``LIRC_NOTIFY_DECODE`` + 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. -LIRC_SETUP_{START,END} +.. _LIRC_SETUP_START: +.. _LIRC_SETUP_END: + +``LIRC_SETUP_{START,END}`` + 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 + ``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 + ``LIRC_SETUP_START`` and ``LIRC_SETUP_END.`` Drivers can also choose to ignore these ioctls. -LIRC_SET_WIDEBAND_RECEIVER +.. _LIRC_SET_WIDEBAND_RECEIVER: + +``LIRC_SET_WIDEBAND_RECEIVER`` + 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 |