1 .. SPDX-License-Identifier: GPL-2.0
2
3 .. include:: <isonum.txt>
4
5 The Samsung S5P/Exynos4 FIMC driver
6 ===================================
7
8 Copyright |copy| 2012 - 2013 Samsung Electroni
9
10 The FIMC (Fully Interactive Mobile Camera) dev
11 SoC Application Processors is an integrated ca
12 space converter, image resizer and rotator. I
13 data from LCD controller (FIMD) through the So
14 path. There are multiple FIMC instances in th
15 slightly different capabilities, like pixel al
16 availability, LCD writeback support, etc. The
17 drivers/media/platform/samsung/exynos4-is dire
18
19 Supported SoCs
20 --------------
21
22 S5PC100 (mem-to-mem only), S5PV210, Exynos4210
23
24 Supported features
25 ------------------
26
27 - camera parallel interface capture (ITU-R.BT6
28 - camera serial interface capture (MIPI-CSI2);
29 - memory-to-memory processing (color space con
30 and rotation);
31 - dynamic pipeline re-configuration at runtime
32 instance to any parallel video input or any
33 - runtime PM and system wide suspend/resume
34
35 Not currently supported
36 -----------------------
37
38 - LCD writeback input
39 - per frame clock gating (mem-to-mem)
40
41 User space interfaces
42 ---------------------
43
44 Media device interface
45 ~~~~~~~~~~~~~~~~~~~~~~
46
47 The driver supports Media Controller API as de
48 The media device driver name is "Samsung S5P F
49
50 The purpose of this interface is to allow chan
51 to the SoC peripheral camera input at runtime
52 connections of the MIPI-CSIS device(s) to the
53
54 The media device interface allows to configure
55 data from the sensor through more than one FIM
56 viewfinder and still capture setup).
57
58 Reconfiguration is done by enabling/disabling
59 during initialization. The internal device top
60 through media entity and links enumeration.
61
62 Memory-to-memory video node
63 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
64
65 V4L2 memory-to-memory interface at /dev/video?
66 video device, it has no media pads. However pl
67 capture video node operation on same FIMC inst
68 detects such cases but the applications should
69 undefined behaviour.
70
71 Capture video node
72 ~~~~~~~~~~~~~~~~~~
73
74 The driver supports V4L2 Video Capture Interfa
75 :ref:`devices`.
76
77 At the capture and mem-to-mem video nodes only
78 supported. For more details see: :ref:`planar-
79
80 Camera capture subdevs
81 ~~~~~~~~~~~~~~~~~~~~~~
82
83 Each FIMC instance exports a sub-device node (
84 node is also created per each available and en
85 MIPI-CSI receiver device (currently up to two)
86
87 sysfs
88 ~~~~~
89
90 In order to enable more precise camera pipelin
91 API the driver creates a sysfs entry associate
92 device. The entry path is: /sys/platform/devic
93
94 In typical use case there could be a following
95 sensor subdev -> mipi-csi subdev -> fimc subde
96
97 When we configure these devices through sub-de
98 configuration flow must be from left to right,
99 configured as last one.
100
101 When we don't use sub-device user space API th
102 devices belonging to the pipeline is done at t
103 The sysfs entry allows to instruct the capture
104 the sub-devices (format, crop), to avoid reset
105 when the last configuration steps at the video
106
107 For full sub-device control support (subdevs c
108 starting streaming):
109
110 .. code-block:: none
111
112 # echo "sub-dev" > /sys/platform/devic
113
114 For V4L2 video node control only (subdevs conf
115 driver):
116
117 .. code-block:: none
118
119 # echo "vid-dev" > /sys/platform/devic
120
121 This is a default option.
122
123 5. Device mapping to video and subdev device n
124 ----------------------------------------------
125
126 There are associated two video device nodes wi
127 hardware - video capture and mem-to-mem and ad
128 more precise FIMC capture subsystem control. I
129 sub-device node is created per each MIPI-CSIS
130
131 How to find out which /dev/video? or /dev/v4l-
132 device?
133
134 You can either grep through the kernel log to
135
136 .. code-block:: none
137
138 # dmesg | grep -i fimc
139
140 (note that udev, if present, might still have
141
142 or retrieve the information from /dev/media? w
143
144 .. code-block:: none
145
146 # media-ctl -p
147
148 7. Build
149 --------
150
151 If the driver is built as a loadable kernel mo
152 two modules are created (in addition to the co
153 optional s5p-csis.ko (MIPI-CSI receiver subdev
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