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gerrit-public.fairphone.software / kernel / msm-4.19 / 6ab1a322dcafc2de6a2f9a5f876e661b4457d0c9 / . / Documentation / media / uapi / gen-errors.rst
blob: 6e983b9880fce2df7112e7f3b14365057a6db3da [file] [log] [blame]
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]1.. -*- coding: utf-8; mode: rst -*-
2
3.. _gen_errors:
4
5*******************
6Generic Error Codes
7*******************
8
9
10.. _gen-errors:
11
Mauro Carvalho Chehab42858b52016-08-19 09:46:28 -0300[diff] [blame]12.. tabularcolumns:: |p{2.5cm}|p{15.0cm}|
Mauro Carvalho Chehab5bd4bb72016-08-17 08:14:19 -0300[diff] [blame]13
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]14.. flat-table:: Generic error codes
15 :header-rows: 0
16 :stub-columns: 0
Mauro Carvalho Chehabdf947112016-07-06 07:58:20 -0300[diff] [blame]17 :widths: 1 16
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]18
19
20 - .. row 1
21
Mauro Carvalho Chehabcdb4af02016-07-03 11:53:09 -0300[diff] [blame]22 - ``EAGAIN`` (aka ``EWOULDBLOCK``)
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]23
24 - The ioctl can't be handled because the device is in state where it
Mauro Carvalho Chehab0579e6e2016-07-04 16:25:48 -0300[diff] [blame]25 can't perform it. This could happen for example in case where
26 device is sleeping and ioctl is performed to query statistics. It
27 is also returned when the ioctl would need to wait for an event,
28 but the device was opened in non-blocking mode.
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]29
30 - .. row 2
31
Mauro Carvalho Chehabcdb4af02016-07-03 11:53:09 -0300[diff] [blame]32 - ``EBADF``
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]33
34 - The file descriptor is not a valid.
35
36 - .. row 3
37
Mauro Carvalho Chehabcdb4af02016-07-03 11:53:09 -0300[diff] [blame]38 - ``EBUSY``
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]39
40 - The ioctl can't be handled because the device is busy. This is
Mauro Carvalho Chehab0579e6e2016-07-04 16:25:48 -0300[diff] [blame]41 typically return while device is streaming, and an ioctl tried to
42 change something that would affect the stream, or would require
43 the usage of a hardware resource that was already allocated. The
44 ioctl must not be retried without performing another action to fix
45 the problem first (typically: stop the stream before retrying).
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]46
47 - .. row 4
48
Mauro Carvalho Chehabcdb4af02016-07-03 11:53:09 -0300[diff] [blame]49 - ``EFAULT``
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]50
51 - There was a failure while copying data from/to userspace, probably
Mauro Carvalho Chehab0579e6e2016-07-04 16:25:48 -0300[diff] [blame]52 caused by an invalid pointer reference.
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]53
54 - .. row 5
55
Mauro Carvalho Chehabcdb4af02016-07-03 11:53:09 -0300[diff] [blame]56 - ``EINVAL``
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]57
58 - One or more of the ioctl parameters are invalid or out of the
Mauro Carvalho Chehab0579e6e2016-07-04 16:25:48 -0300[diff] [blame]59 allowed range. This is a widely used error code. See the
60 individual ioctl requests for specific causes.
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]61
62 - .. row 6
63
Mauro Carvalho Chehabcdb4af02016-07-03 11:53:09 -0300[diff] [blame]64 - ``ENODEV``
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]65
66 - Device not found or was removed.
67
68 - .. row 7
69
Mauro Carvalho Chehabcdb4af02016-07-03 11:53:09 -0300[diff] [blame]70 - ``ENOMEM``
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]71
72 - There's not enough memory to handle the desired operation.
73
74 - .. row 8
75
Mauro Carvalho Chehabcdb4af02016-07-03 11:53:09 -0300[diff] [blame]76 - ``ENOTTY``
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]77
78 - The ioctl is not supported by the driver, actually meaning that
Mauro Carvalho Chehab0579e6e2016-07-04 16:25:48 -0300[diff] [blame]79 the required functionality is not available, or the file
80 descriptor is not for a media device.
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]81
82 - .. row 9
83
Mauro Carvalho Chehabcdb4af02016-07-03 11:53:09 -0300[diff] [blame]84 - ``ENOSPC``
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]85
86 - On USB devices, the stream ioctl's can return this error, meaning
Mauro Carvalho Chehab0579e6e2016-07-04 16:25:48 -0300[diff] [blame]87 that this request would overcommit the usb bandwidth reserved for
88 periodic transfers (up to 80% of the USB bandwidth).
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]89
90 - .. row 10
91
Mauro Carvalho Chehabcdb4af02016-07-03 11:53:09 -0300[diff] [blame]92 - ``EPERM``
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]93
94 - Permission denied. Can be returned if the device needs write
Mauro Carvalho Chehab0579e6e2016-07-04 16:25:48 -0300[diff] [blame]95 permission, or some special capabilities is needed (e. g. root)
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]96
Mauro Carvalho Chehab706f8a92016-07-10 11:57:43 -0300[diff] [blame]97.. note::
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]98
Mauro Carvalho Chehab706f8a92016-07-10 11:57:43 -0300[diff] [blame]99 #. This list is not exaustive; ioctls may return other error codes.
100 Since errors may have side effects such as a driver reset,
101 applications should abort on unexpected errors, or otherwise
102 assume that the device is in a bad state.
Markus Heiser5377d912016-06-30 15:18:56 +0200[diff] [blame]103
Mauro Carvalho Chehab706f8a92016-07-10 11:57:43 -0300[diff] [blame]104 #. Request-specific error codes are listed in the individual
105 requests descriptions.