1 .. SPDX-License-Identifier: GFDL-1.1-no-invari 1 .. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
2 .. c:namespace:: CEC 2 .. c:namespace:: CEC
3 3
4 .. _CEC_TRANSMIT: 4 .. _CEC_TRANSMIT:
5 .. _CEC_RECEIVE: 5 .. _CEC_RECEIVE:
6 6
7 *********************************** 7 ***********************************
8 ioctls CEC_RECEIVE and CEC_TRANSMIT 8 ioctls CEC_RECEIVE and CEC_TRANSMIT
9 *********************************** 9 ***********************************
10 10
11 Name 11 Name
12 ==== 12 ====
13 13
14 CEC_RECEIVE, CEC_TRANSMIT - Receive or transmi 14 CEC_RECEIVE, CEC_TRANSMIT - Receive or transmit a CEC message
15 15
16 Synopsis 16 Synopsis
17 ======== 17 ========
18 18
19 .. c:macro:: CEC_RECEIVE 19 .. c:macro:: CEC_RECEIVE
20 20
21 ``int ioctl(int fd, CEC_RECEIVE, struct cec_ms 21 ``int ioctl(int fd, CEC_RECEIVE, struct cec_msg *argp)``
22 22
23 .. c:macro:: CEC_TRANSMIT 23 .. c:macro:: CEC_TRANSMIT
24 24
25 ``int ioctl(int fd, CEC_TRANSMIT, struct cec_m 25 ``int ioctl(int fd, CEC_TRANSMIT, struct cec_msg *argp)``
26 26
27 Arguments 27 Arguments
28 ========= 28 =========
29 29
30 ``fd`` 30 ``fd``
31 File descriptor returned by :c:func:`open( 31 File descriptor returned by :c:func:`open()`.
32 32
33 ``argp`` 33 ``argp``
34 Pointer to struct cec_msg. 34 Pointer to struct cec_msg.
35 35
36 Description 36 Description
37 =========== 37 ===========
38 38
39 To receive a CEC message the application has t 39 To receive a CEC message the application has to fill in the
40 ``timeout`` field of struct :c:type:`cec_msg` 40 ``timeout`` field of struct :c:type:`cec_msg` and pass it to
41 :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`. 41 :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`.
42 If the file descriptor is in non-blocking mode 42 If the file descriptor is in non-blocking mode and there are no received
43 messages pending, then it will return -1 and s 43 messages pending, then it will return -1 and set errno to the ``EAGAIN``
44 error code. If the file descriptor is in block 44 error code. If the file descriptor is in blocking mode and ``timeout``
45 is non-zero and no message arrived within ``ti 45 is non-zero and no message arrived within ``timeout`` milliseconds, then
46 it will return -1 and set errno to the ``ETIME 46 it will return -1 and set errno to the ``ETIMEDOUT`` error code.
47 47
48 A received message can be: 48 A received message can be:
49 49
50 1. a message received from another CEC device 50 1. a message received from another CEC device (the ``sequence`` field will
51 be 0, ``tx_status`` will be 0 and ``rx_stat !! 51 be 0).
52 2. the transmit result of an earlier non-block !! 52 2. the result of an earlier non-blocking transmit (the ``sequence`` field will
53 field will be non-zero, ``tx_status`` will !! 53 be non-zero).
54 will be 0). <<
55 3. the reply to an earlier non-blocking transm <<
56 be non-zero, ``tx_status`` will be 0 and `` <<
57 54
58 To send a CEC message the application has to f 55 To send a CEC message the application has to fill in the struct
59 :c:type:`cec_msg` and pass it to :ref:`ioctl C 56 :c:type:`cec_msg` and pass it to :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>`.
60 The :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` i 57 The :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` is only available if
61 ``CEC_CAP_TRANSMIT`` is set. If there is no mo 58 ``CEC_CAP_TRANSMIT`` is set. If there is no more room in the transmit
62 queue, then it will return -1 and set errno to 59 queue, then it will return -1 and set errno to the ``EBUSY`` error code.
63 The transmit queue has enough room for 18 mess 60 The transmit queue has enough room for 18 messages (about 1 second worth
64 of 2-byte messages). Note that the CEC kernel 61 of 2-byte messages). Note that the CEC kernel framework will also reply
65 to core messages (see :ref:`cec-core-processin 62 to core messages (see :ref:`cec-core-processing`), so it is not a good
66 idea to fully fill up the transmit queue. 63 idea to fully fill up the transmit queue.
67 64
68 If the file descriptor is in non-blocking mode 65 If the file descriptor is in non-blocking mode then the transmit will
69 return 0 and the result of the transmit will b 66 return 0 and the result of the transmit will be available via
70 :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>` once th !! 67 :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>` once the transmit has finished
71 If a non-blocking transmit also specified wait !! 68 (including waiting for a reply, if requested).
72 the reply will arrive in a later message. The !! 69
73 be used to associate both transmit results and !! 70 The ``sequence`` field is filled in for every transmit and this can be
74 transmit. !! 71 checked against the received messages to find the corresponding transmit
>> 72 result.
75 73
76 Normally calling :ref:`ioctl CEC_TRANSMIT <CEC 74 Normally calling :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` when the physical
77 address is invalid (due to e.g. a disconnect) 75 address is invalid (due to e.g. a disconnect) will return ``ENONET``.
78 76
79 However, the CEC specification allows sending 77 However, the CEC specification allows sending messages from 'Unregistered' to
80 'TV' when the physical address is invalid sinc 78 'TV' when the physical address is invalid since some TVs pull the hotplug detect
81 pin of the HDMI connector low when they go int 79 pin of the HDMI connector low when they go into standby, or when switching to
82 another input. 80 another input.
83 81
84 When the hotplug detect pin goes low the EDID 82 When the hotplug detect pin goes low the EDID disappears, and thus the
85 physical address, but the cable is still conne 83 physical address, but the cable is still connected and CEC still works.
86 In order to detect/wake up the device it is al 84 In order to detect/wake up the device it is allowed to send poll and 'Image/Text
87 View On' messages from initiator 0xf ('Unregis 85 View On' messages from initiator 0xf ('Unregistered') to destination 0 ('TV').
88 86
89 .. tabularcolumns:: |p{1.0cm}|p{3.5cm}|p{12.8c 87 .. tabularcolumns:: |p{1.0cm}|p{3.5cm}|p{12.8cm}|
90 88
91 .. c:type:: cec_msg 89 .. c:type:: cec_msg
92 90
93 .. cssclass:: longtable 91 .. cssclass:: longtable
94 92
95 .. flat-table:: struct cec_msg 93 .. flat-table:: struct cec_msg
96 :header-rows: 0 94 :header-rows: 0
97 :stub-columns: 0 95 :stub-columns: 0
98 :widths: 1 1 16 96 :widths: 1 1 16
99 97
100 * - __u64 98 * - __u64
101 - ``tx_ts`` 99 - ``tx_ts``
102 - Timestamp in ns of when the last byte 100 - Timestamp in ns of when the last byte of the message was transmitted.
103 The timestamp has been taken from the 101 The timestamp has been taken from the ``CLOCK_MONOTONIC`` clock. To access
104 the same clock from userspace use :c:f 102 the same clock from userspace use :c:func:`clock_gettime`.
105 * - __u64 103 * - __u64
106 - ``rx_ts`` 104 - ``rx_ts``
107 - Timestamp in ns of when the last byte 105 - Timestamp in ns of when the last byte of the message was received.
108 The timestamp has been taken from the 106 The timestamp has been taken from the ``CLOCK_MONOTONIC`` clock. To access
109 the same clock from userspace use :c:f 107 the same clock from userspace use :c:func:`clock_gettime`.
110 * - __u32 108 * - __u32
111 - ``len`` 109 - ``len``
112 - The length of the message. For :ref:`i 110 - The length of the message. For :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` this is filled in
113 by the application. The driver will fi 111 by the application. The driver will fill this in for
114 :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>` 112 :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`. For :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` it will be
115 filled in by the driver with the lengt 113 filled in by the driver with the length of the reply message if ``reply`` was set.
116 * - __u32 114 * - __u32
117 - ``timeout`` 115 - ``timeout``
118 - The timeout in milliseconds. This is t 116 - The timeout in milliseconds. This is the time the device will wait
119 for a message to be received before ti 117 for a message to be received before timing out. If it is set to 0,
120 then it will wait indefinitely when it 118 then it will wait indefinitely when it is called by :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`.
121 If it is 0 and it is called by :ref:`i 119 If it is 0 and it is called by :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>`,
122 then it will be replaced by 1000 if th 120 then it will be replaced by 1000 if the ``reply`` is non-zero or
123 ignored if ``reply`` is 0. 121 ignored if ``reply`` is 0.
124 * - __u32 122 * - __u32
125 - ``sequence`` 123 - ``sequence``
126 - A non-zero sequence number is automati 124 - A non-zero sequence number is automatically assigned by the CEC framework
127 for all transmitted messages. It is us 125 for all transmitted messages. It is used by the CEC framework when it queues
128 the transmit result for a non-blocking !! 126 the transmit result (when transmit was called in non-blocking mode). This
129 to associate the received message with !! 127 allows the application to associate the received message with the original
130 !! 128 transmit.
131 In addition, if a non-blocking transmi <<
132 was not 0), then the ``sequence`` fiel <<
133 value of the original transmit. This a <<
134 received message with the original tra <<
135 * - __u32 129 * - __u32
136 - ``flags`` 130 - ``flags``
137 - Flags. See :ref:`cec-msg-flags` for a 131 - Flags. See :ref:`cec-msg-flags` for a list of available flags.
138 * - __u8 132 * - __u8
>> 133 - ``tx_status``
>> 134 - The status bits of the transmitted message. See
>> 135 :ref:`cec-tx-status` for the possible status values. It is 0 if
>> 136 this message was received, not transmitted.
>> 137 * - __u8
139 - ``msg[16]`` 138 - ``msg[16]``
140 - The message payload. For :ref:`ioctl C 139 - The message payload. For :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` this is filled in by the
141 application. The driver will fill this 140 application. The driver will fill this in for :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`.
142 For :ref:`ioctl CEC_TRANSMIT <CEC_TRAN 141 For :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` it will be filled in by the driver with
143 the payload of the reply message if `` 142 the payload of the reply message if ``timeout`` was set.
144 * - __u8 143 * - __u8
145 - ``reply`` 144 - ``reply``
146 - Wait until this message is replied. If 145 - Wait until this message is replied. If ``reply`` is 0 and the
147 ``timeout`` is 0, then don't wait for 146 ``timeout`` is 0, then don't wait for a reply but return after
148 transmitting the message. Ignored by : 147 transmitting the message. Ignored by :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`.
149 The case where ``reply`` is 0 (this is 148 The case where ``reply`` is 0 (this is the opcode for the Feature Abort
150 message) and ``timeout`` is non-zero i 149 message) and ``timeout`` is non-zero is specifically allowed to make it
151 possible to send a message and wait up 150 possible to send a message and wait up to ``timeout`` milliseconds for a
152 Feature Abort reply. In this case ``rx 151 Feature Abort reply. In this case ``rx_status`` will either be set
153 to :ref:`CEC_RX_STATUS_TIMEOUT <CEC-RX 152 to :ref:`CEC_RX_STATUS_TIMEOUT <CEC-RX-STATUS-TIMEOUT>` or
154 :ref:`CEC_RX_STATUS_FEATURE_ABORT <CEC 153 :ref:`CEC_RX_STATUS_FEATURE_ABORT <CEC-RX-STATUS-FEATURE-ABORT>`.
155 154
156 If the transmitter message is ``CEC_MS 155 If the transmitter message is ``CEC_MSG_INITIATE_ARC`` then the ``reply``
157 values ``CEC_MSG_REPORT_ARC_INITIATED` 156 values ``CEC_MSG_REPORT_ARC_INITIATED`` and ``CEC_MSG_REPORT_ARC_TERMINATED``
158 are processed differently: either valu 157 are processed differently: either value will match both possible replies.
159 The reason is that the ``CEC_MSG_INITI 158 The reason is that the ``CEC_MSG_INITIATE_ARC`` message is the only CEC
160 message that has two possible replies 159 message that has two possible replies other than Feature Abort. The
161 ``reply`` field will be updated with t 160 ``reply`` field will be updated with the actual reply so that it is
162 synchronized with the contents of the 161 synchronized with the contents of the received message.
163 * - __u8 162 * - __u8
164 - ``rx_status`` 163 - ``rx_status``
165 - The status bits of the received messag 164 - The status bits of the received message. See
166 :ref:`cec-rx-status` for the possible !! 165 :ref:`cec-rx-status` for the possible status values. It is 0 if
>> 166 this message was transmitted, not received, unless this is the
>> 167 reply to a transmitted message. In that case both ``rx_status``
>> 168 and ``tx_status`` are set.
167 * - __u8 169 * - __u8
168 - ``tx_status`` 170 - ``tx_status``
169 - The status bits of the transmitted mes 171 - The status bits of the transmitted message. See
170 :ref:`cec-tx-status` for the possible !! 172 :ref:`cec-tx-status` for the possible status values. It is 0 if
171 When calling :ref:`ioctl CEC_TRANSMIT !! 173 this message was received, not transmitted.
172 this field will be 0 if the transmit s <<
173 result is known immediately. The latte <<
174 to transmit a Poll message to yourself <<
175 :ref:`CEC_TX_STATUS_NACK <CEC-TX-STATU <<
176 transmitting the Poll message. <<
177 * - __u8 174 * - __u8
178 - ``tx_arb_lost_cnt`` 175 - ``tx_arb_lost_cnt``
179 - A counter of the number of transmit at 176 - A counter of the number of transmit attempts that resulted in the
180 Arbitration Lost error. This is only s 177 Arbitration Lost error. This is only set if the hardware supports
181 this, otherwise it is always 0. This c 178 this, otherwise it is always 0. This counter is only valid if the
182 :ref:`CEC_TX_STATUS_ARB_LOST <CEC-TX-S 179 :ref:`CEC_TX_STATUS_ARB_LOST <CEC-TX-STATUS-ARB-LOST>` status bit is set.
183 * - __u8 180 * - __u8
184 - ``tx_nack_cnt`` 181 - ``tx_nack_cnt``
185 - A counter of the number of transmit at 182 - A counter of the number of transmit attempts that resulted in the
186 Not Acknowledged error. This is only s 183 Not Acknowledged error. This is only set if the hardware supports
187 this, otherwise it is always 0. This c 184 this, otherwise it is always 0. This counter is only valid if the
188 :ref:`CEC_TX_STATUS_NACK <CEC-TX-STATU 185 :ref:`CEC_TX_STATUS_NACK <CEC-TX-STATUS-NACK>` status bit is set.
189 * - __u8 186 * - __u8
190 - ``tx_low_drive_cnt`` 187 - ``tx_low_drive_cnt``
191 - A counter of the number of transmit at 188 - A counter of the number of transmit attempts that resulted in the
192 Arbitration Lost error. This is only s 189 Arbitration Lost error. This is only set if the hardware supports
193 this, otherwise it is always 0. This c 190 this, otherwise it is always 0. This counter is only valid if the
194 :ref:`CEC_TX_STATUS_LOW_DRIVE <CEC-TX- 191 :ref:`CEC_TX_STATUS_LOW_DRIVE <CEC-TX-STATUS-LOW-DRIVE>` status bit is set.
195 * - __u8 192 * - __u8
196 - ``tx_error_cnt`` 193 - ``tx_error_cnt``
197 - A counter of the number of transmit er 194 - A counter of the number of transmit errors other than Arbitration
198 Lost or Not Acknowledged. This is only 195 Lost or Not Acknowledged. This is only set if the hardware
199 supports this, otherwise it is always 196 supports this, otherwise it is always 0. This counter is only
200 valid if the :ref:`CEC_TX_STATUS_ERROR 197 valid if the :ref:`CEC_TX_STATUS_ERROR <CEC-TX-STATUS-ERROR>` status bit is set.
201 198
202 .. tabularcolumns:: |p{6.2cm}|p{1.0cm}|p{10.1c 199 .. tabularcolumns:: |p{6.2cm}|p{1.0cm}|p{10.1cm}|
203 200
204 .. _cec-msg-flags: 201 .. _cec-msg-flags:
205 202
206 .. flat-table:: Flags for struct cec_msg 203 .. flat-table:: Flags for struct cec_msg
207 :header-rows: 0 204 :header-rows: 0
208 :stub-columns: 0 205 :stub-columns: 0
209 :widths: 3 1 4 206 :widths: 3 1 4
210 207
211 * .. _`CEC-MSG-FL-REPLY-TO-FOLLOWERS`: 208 * .. _`CEC-MSG-FL-REPLY-TO-FOLLOWERS`:
212 209
213 - ``CEC_MSG_FL_REPLY_TO_FOLLOWERS`` 210 - ``CEC_MSG_FL_REPLY_TO_FOLLOWERS``
214 - 1 211 - 1
215 - If a CEC transmit expects a reply, the 212 - If a CEC transmit expects a reply, then by default that reply is only sent to
216 the filehandle that called :ref:`ioctl 213 the filehandle that called :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>`. If this
217 flag is set, then the reply is also se 214 flag is set, then the reply is also sent to all followers, if any. If the
218 filehandle that called :ref:`ioctl CEC 215 filehandle that called :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` is also a
219 follower, then that filehandle will re 216 follower, then that filehandle will receive the reply twice: once as the
220 result of the :ref:`ioctl CEC_TRANSMIT 217 result of the :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>`, and once via
221 :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>` 218 :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>`.
222 219
223 * .. _`CEC-MSG-FL-RAW`: 220 * .. _`CEC-MSG-FL-RAW`:
224 221
225 - ``CEC_MSG_FL_RAW`` 222 - ``CEC_MSG_FL_RAW``
226 - 2 223 - 2
227 - Normally CEC messages are validated be 224 - Normally CEC messages are validated before transmitting them. If this
228 flag is set when :ref:`ioctl CEC_TRANS 225 flag is set when :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` is called,
229 then no validation takes place and the 226 then no validation takes place and the message is transmitted as-is.
230 This is useful when debugging CEC issu 227 This is useful when debugging CEC issues.
231 This flag is only allowed if the proce 228 This flag is only allowed if the process has the ``CAP_SYS_RAWIO``
232 capability. If that is not set, then t 229 capability. If that is not set, then the ``EPERM`` error code is
233 returned. 230 returned.
234 <<
235 * .. _`CEC-MSG-FL-REPLY-VENDOR-ID`: <<
236 <<
237 - ``CEC_MSG_FL_REPLY_VENDOR_ID`` <<
238 - 4 <<
239 - This flag is only available if the ``C <<
240 is set. If this flag is set, then the <<
241 the ``CEC_MSG_VENDOR_COMMAND_WITH_ID`` <<
242 (in bytes 1-4 of the message), followe <<
243 ``reply`` field. <<
244 <<
245 Note that this assumes that the byte a <<
246 vendor-specific opcode. <<
247 <<
248 This flag makes it easier to wait for <<
249 231
250 .. tabularcolumns:: |p{5.6cm}|p{0.9cm}|p{10.8c 232 .. tabularcolumns:: |p{5.6cm}|p{0.9cm}|p{10.8cm}|
251 233
252 .. _cec-tx-status: 234 .. _cec-tx-status:
253 235
254 .. flat-table:: CEC Transmit Status 236 .. flat-table:: CEC Transmit Status
255 :header-rows: 0 237 :header-rows: 0
256 :stub-columns: 0 238 :stub-columns: 0
257 :widths: 3 1 16 239 :widths: 3 1 16
258 240
259 * .. _`CEC-TX-STATUS-OK`: 241 * .. _`CEC-TX-STATUS-OK`:
260 242
261 - ``CEC_TX_STATUS_OK`` 243 - ``CEC_TX_STATUS_OK``
262 - 0x01 244 - 0x01
263 - The message was transmitted successful 245 - The message was transmitted successfully. This is mutually
264 exclusive with :ref:`CEC_TX_STATUS_MAX 246 exclusive with :ref:`CEC_TX_STATUS_MAX_RETRIES <CEC-TX-STATUS-MAX-RETRIES>`.
265 Other bits can still be set if earlier 247 Other bits can still be set if earlier attempts met with failure before
266 the transmit was eventually successful 248 the transmit was eventually successful.
267 * .. _`CEC-TX-STATUS-ARB-LOST`: 249 * .. _`CEC-TX-STATUS-ARB-LOST`:
268 250
269 - ``CEC_TX_STATUS_ARB_LOST`` 251 - ``CEC_TX_STATUS_ARB_LOST``
270 - 0x02 252 - 0x02
271 - CEC line arbitration was lost, i.e. an 253 - CEC line arbitration was lost, i.e. another transmit started at the
272 same time with a higher priority. Opti 254 same time with a higher priority. Optional status, not all hardware
273 can detect this error condition. 255 can detect this error condition.
274 * .. _`CEC-TX-STATUS-NACK`: 256 * .. _`CEC-TX-STATUS-NACK`:
275 257
276 - ``CEC_TX_STATUS_NACK`` 258 - ``CEC_TX_STATUS_NACK``
277 - 0x04 259 - 0x04
278 - Message was not acknowledged. Note tha 260 - Message was not acknowledged. Note that some hardware cannot tell apart
279 a 'Not Acknowledged' status from other 261 a 'Not Acknowledged' status from other error conditions, i.e. the result
280 of a transmit is just OK or FAIL. In t 262 of a transmit is just OK or FAIL. In that case this status will be
281 returned when the transmit failed. 263 returned when the transmit failed.
282 * .. _`CEC-TX-STATUS-LOW-DRIVE`: 264 * .. _`CEC-TX-STATUS-LOW-DRIVE`:
283 265
284 - ``CEC_TX_STATUS_LOW_DRIVE`` 266 - ``CEC_TX_STATUS_LOW_DRIVE``
285 - 0x08 267 - 0x08
286 - Low drive was detected on the CEC bus. 268 - Low drive was detected on the CEC bus. This indicates that a
287 follower detected an error on the bus 269 follower detected an error on the bus and requests a
288 retransmission. Optional status, not a 270 retransmission. Optional status, not all hardware can detect this
289 error condition. 271 error condition.
290 * .. _`CEC-TX-STATUS-ERROR`: 272 * .. _`CEC-TX-STATUS-ERROR`:
291 273
292 - ``CEC_TX_STATUS_ERROR`` 274 - ``CEC_TX_STATUS_ERROR``
293 - 0x10 275 - 0x10
294 - Some error occurred. This is used for 276 - Some error occurred. This is used for any errors that do not fit
295 ``CEC_TX_STATUS_ARB_LOST`` or ``CEC_TX 277 ``CEC_TX_STATUS_ARB_LOST`` or ``CEC_TX_STATUS_LOW_DRIVE``, either because
296 the hardware could not tell which erro 278 the hardware could not tell which error occurred, or because the hardware
297 tested for other conditions besides th 279 tested for other conditions besides those two. Optional status.
298 * .. _`CEC-TX-STATUS-MAX-RETRIES`: 280 * .. _`CEC-TX-STATUS-MAX-RETRIES`:
299 281
300 - ``CEC_TX_STATUS_MAX_RETRIES`` 282 - ``CEC_TX_STATUS_MAX_RETRIES``
301 - 0x20 283 - 0x20
302 - The transmit failed after one or more 284 - The transmit failed after one or more retries. This status bit is
303 mutually exclusive with :ref:`CEC_TX_S 285 mutually exclusive with :ref:`CEC_TX_STATUS_OK <CEC-TX-STATUS-OK>`.
304 Other bits can still be set to explain 286 Other bits can still be set to explain which failures were seen.
305 * .. _`CEC-TX-STATUS-ABORTED`: 287 * .. _`CEC-TX-STATUS-ABORTED`:
306 288
307 - ``CEC_TX_STATUS_ABORTED`` 289 - ``CEC_TX_STATUS_ABORTED``
308 - 0x40 290 - 0x40
309 - The transmit was aborted due to an HDM 291 - The transmit was aborted due to an HDMI disconnect, or the adapter
310 was unconfigured, or a transmit was in 292 was unconfigured, or a transmit was interrupted, or the driver
311 returned an error when attempting to s 293 returned an error when attempting to start a transmit.
312 * .. _`CEC-TX-STATUS-TIMEOUT`: 294 * .. _`CEC-TX-STATUS-TIMEOUT`:
313 295
314 - ``CEC_TX_STATUS_TIMEOUT`` 296 - ``CEC_TX_STATUS_TIMEOUT``
315 - 0x80 297 - 0x80
316 - The transmit timed out. This should no 298 - The transmit timed out. This should not normally happen and this
317 indicates a driver problem. 299 indicates a driver problem.
318 300
319 .. tabularcolumns:: |p{5.6cm}|p{0.9cm}|p{10.8c 301 .. tabularcolumns:: |p{5.6cm}|p{0.9cm}|p{10.8cm}|
320 302
321 .. _cec-rx-status: 303 .. _cec-rx-status:
322 304
323 .. flat-table:: CEC Receive Status 305 .. flat-table:: CEC Receive Status
324 :header-rows: 0 306 :header-rows: 0
325 :stub-columns: 0 307 :stub-columns: 0
326 :widths: 3 1 16 308 :widths: 3 1 16
327 309
328 * .. _`CEC-RX-STATUS-OK`: 310 * .. _`CEC-RX-STATUS-OK`:
329 311
330 - ``CEC_RX_STATUS_OK`` 312 - ``CEC_RX_STATUS_OK``
331 - 0x01 313 - 0x01
332 - The message was received successfully. 314 - The message was received successfully.
333 * .. _`CEC-RX-STATUS-TIMEOUT`: 315 * .. _`CEC-RX-STATUS-TIMEOUT`:
334 316
335 - ``CEC_RX_STATUS_TIMEOUT`` 317 - ``CEC_RX_STATUS_TIMEOUT``
336 - 0x02 318 - 0x02
337 - The reply to an earlier transmitted me 319 - The reply to an earlier transmitted message timed out.
338 * .. _`CEC-RX-STATUS-FEATURE-ABORT`: 320 * .. _`CEC-RX-STATUS-FEATURE-ABORT`:
339 321
340 - ``CEC_RX_STATUS_FEATURE_ABORT`` 322 - ``CEC_RX_STATUS_FEATURE_ABORT``
341 - 0x04 323 - 0x04
342 - The message was received successfully 324 - The message was received successfully but the reply was
343 ``CEC_MSG_FEATURE_ABORT``. This status 325 ``CEC_MSG_FEATURE_ABORT``. This status is only set if this message
344 was the reply to an earlier transmitte 326 was the reply to an earlier transmitted message.
345 * .. _`CEC-RX-STATUS-ABORTED`: 327 * .. _`CEC-RX-STATUS-ABORTED`:
346 328
347 - ``CEC_RX_STATUS_ABORTED`` 329 - ``CEC_RX_STATUS_ABORTED``
348 - 0x08 330 - 0x08
349 - The wait for a reply to an earlier tra 331 - The wait for a reply to an earlier transmitted message was aborted
350 because the HDMI cable was disconnecte 332 because the HDMI cable was disconnected, the adapter was unconfigured
351 or the :ref:`CEC_TRANSMIT <CEC_RECEIVE 333 or the :ref:`CEC_TRANSMIT <CEC_RECEIVE>` that waited for a
352 reply was interrupted. 334 reply was interrupted.
353 335
354 336
355 Return Value 337 Return Value
356 ============ 338 ============
357 339
358 On success 0 is returned, on error -1 and the 340 On success 0 is returned, on error -1 and the ``errno`` variable is set
359 appropriately. The generic error codes are des 341 appropriately. The generic error codes are described at the
360 :ref:`Generic Error Codes <gen-errors>` chapte 342 :ref:`Generic Error Codes <gen-errors>` chapter.
361 343
362 The :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>` can 344 The :ref:`ioctl CEC_RECEIVE <CEC_RECEIVE>` can return the following
363 error codes: 345 error codes:
364 346
365 EAGAIN 347 EAGAIN
366 No messages are in the receive queue, and 348 No messages are in the receive queue, and the filehandle is in non-blocking mode.
367 349
368 ETIMEDOUT 350 ETIMEDOUT
369 The ``timeout`` was reached while waiting 351 The ``timeout`` was reached while waiting for a message.
370 352
371 ERESTARTSYS 353 ERESTARTSYS
372 The wait for a message was interrupted (e. 354 The wait for a message was interrupted (e.g. by Ctrl-C).
373 355
374 The :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` c 356 The :ref:`ioctl CEC_TRANSMIT <CEC_TRANSMIT>` can return the following
375 error codes: 357 error codes:
376 358
377 ENOTTY 359 ENOTTY
378 The ``CEC_CAP_TRANSMIT`` capability wasn't 360 The ``CEC_CAP_TRANSMIT`` capability wasn't set, so this ioctl is not supported.
379 361
380 EPERM 362 EPERM
381 The CEC adapter is not configured, i.e. :r 363 The CEC adapter is not configured, i.e. :ref:`ioctl CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>`
382 has never been called, or ``CEC_MSG_FL_RAW 364 has never been called, or ``CEC_MSG_FL_RAW`` was used from a process that
383 did not have the ``CAP_SYS_RAWIO`` capabil 365 did not have the ``CAP_SYS_RAWIO`` capability.
384 366
385 ENONET 367 ENONET
386 The CEC adapter is not configured, i.e. :r 368 The CEC adapter is not configured, i.e. :ref:`ioctl CEC_ADAP_S_LOG_ADDRS <CEC_ADAP_S_LOG_ADDRS>`
387 was called, but the physical address is in 369 was called, but the physical address is invalid so no logical address was claimed.
388 An exception is made in this case for tran 370 An exception is made in this case for transmits from initiator 0xf ('Unregistered')
389 to destination 0 ('TV'). In that case the 371 to destination 0 ('TV'). In that case the transmit will proceed as usual.
390 372
391 EBUSY 373 EBUSY
392 Another filehandle is in exclusive followe 374 Another filehandle is in exclusive follower or initiator mode, or the filehandle
393 is in mode ``CEC_MODE_NO_INITIATOR``. This 375 is in mode ``CEC_MODE_NO_INITIATOR``. This is also returned if the transmit
394 queue is full. 376 queue is full.
395 377
396 EINVAL 378 EINVAL
397 The contents of struct :c:type:`cec_msg` i 379 The contents of struct :c:type:`cec_msg` is invalid.
398 380
399 ERESTARTSYS 381 ERESTARTSYS
400 The wait for a successful transmit was int 382 The wait for a successful transmit was interrupted (e.g. by Ctrl-C).
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