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authorLinus Torvalds <torvalds@linux-foundation.org>2012-06-01 19:57:51 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-06-01 19:57:51 -0400
commit804ce9866d56130032c9c8afc90a1297b7deed56 (patch)
tree6dd70984f411d2a3624d3f8db7facc3d6396b9ad /Documentation
parentf5e7e844a571124ffc117d4696787d6afc4fc5ae (diff)
parentc895305e806b4346006d3cfba2b432d52268ecd3 (diff)
Merge tag 'fbdev-updates-for-3.5' of git://github.com/schandinat/linux-2.6
Pull fbdev updates from Florian Tobias Schandinat: - driver for AUO-K1900 and AUO-K1901 epaper controller - large updates for OMAP (e.g. decouple HDMI audio and video) - some updates for Exynos and SH Mobile - various other small fixes and cleanups * tag 'fbdev-updates-for-3.5' of git://github.com/schandinat/linux-2.6: (130 commits) video: bfin_adv7393fb: Fix cleanup code video: exynos_dp: reduce delay time when configuring video setting video: exynos_dp: move sw reset prioir to enabling sw defined function video: exynos_dp: use devm_ functions fb: handle NULL pointers in framebuffer release OMAPDSS: HDMI: OMAP4: Update IRQ flags for the HPD IRQ request OMAPDSS: Apply VENC timings even if panel is disabled OMAPDSS: VENC/DISPC: Delay dividing Y resolution for managers connected to VENC OMAPDSS: DISPC: Support rotation through TILER OMAPDSS: VRFB: remove compiler warnings when CONFIG_BUG=n OMAPFB: remove compiler warnings when CONFIG_BUG=n OMAPDSS: remove compiler warnings when CONFIG_BUG=n OMAPDSS: DISPC: fix usage of dispc_ovl_set_accu_uv OMAPDSS: use DSI_FIFO_BUG workaround only for manual update displays OMAPDSS: DSI: Support command mode interleaving during video mode blanking periods OMAPDSS: DISPC: Update Accumulator configuration for chroma plane drivers/video: fsl-diu-fb: don't initialize the THRESHOLDS registers video: exynos mipi dsi: support reverse panel type video: exynos mipi dsi: Properly interpret the interrupt source flags video: exynos mipi dsi: Avoid races in probe() ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/arm/OMAP/DSS46
1 files changed, 46 insertions, 0 deletions
diff --git a/Documentation/arm/OMAP/DSS b/Documentation/arm/OMAP/DSS
index 888ae7b83ae4..a564ceea9e98 100644
--- a/Documentation/arm/OMAP/DSS
+++ b/Documentation/arm/OMAP/DSS
@@ -47,6 +47,51 @@ flexible way to enable non-common multi-display configuration. In addition to
47modelling the hardware overlays, omapdss supports virtual overlays and overlay 47modelling the hardware overlays, omapdss supports virtual overlays and overlay
48managers. These can be used when updating a display with CPU or system DMA. 48managers. These can be used when updating a display with CPU or system DMA.
49 49
50omapdss driver support for audio
51--------------------------------
52There exist several display technologies and standards that support audio as
53well. Hence, it is relevant to update the DSS device driver to provide an audio
54interface that may be used by an audio driver or any other driver interested in
55the functionality.
56
57The audio_enable function is intended to prepare the relevant
58IP for playback (e.g., enabling an audio FIFO, taking in/out of reset
59some IP, enabling companion chips, etc). It is intended to be called before
60audio_start. The audio_disable function performs the reverse operation and is
61intended to be called after audio_stop.
62
63While a given DSS device driver may support audio, it is possible that for
64certain configurations audio is not supported (e.g., an HDMI display using a
65VESA video timing). The audio_supported function is intended to query whether
66the current configuration of the display supports audio.
67
68The audio_config function is intended to configure all the relevant audio
69parameters of the display. In order to make the function independent of any
70specific DSS device driver, a struct omap_dss_audio is defined. Its purpose
71is to contain all the required parameters for audio configuration. At the
72moment, such structure contains pointers to IEC-60958 channel status word
73and CEA-861 audio infoframe structures. This should be enough to support
74HDMI and DisplayPort, as both are based on CEA-861 and IEC-60958.
75
76The audio_enable/disable, audio_config and audio_supported functions could be
77implemented as functions that may sleep. Hence, they should not be called
78while holding a spinlock or a readlock.
79
80The audio_start/audio_stop function is intended to effectively start/stop audio
81playback after the configuration has taken place. These functions are designed
82to be used in an atomic context. Hence, audio_start should return quickly and be
83called only after all the needed resources for audio playback (audio FIFOs,
84DMA channels, companion chips, etc) have been enabled to begin data transfers.
85audio_stop is designed to only stop the audio transfers. The resources used
86for playback are released using audio_disable.
87
88The enum omap_dss_audio_state may be used to help the implementations of
89the interface to keep track of the audio state. The initial state is _DISABLED;
90then, the state transitions to _CONFIGURED, and then, when it is ready to
91play audio, to _ENABLED. The state _PLAYING is used when the audio is being
92rendered.
93
94
50Panel and controller drivers 95Panel and controller drivers
51---------------------------- 96----------------------------
52 97
@@ -156,6 +201,7 @@ timings Display timings (pixclock,xres/hfp/hbp/hsw,yres/vfp/vbp/vsw)
156 "pal" and "ntsc" 201 "pal" and "ntsc"
157panel_name 202panel_name
158tear_elim Tearing elimination 0=off, 1=on 203tear_elim Tearing elimination 0=off, 1=on
204output_type Output type (video encoder only): "composite" or "svideo"
159 205
160There are also some debugfs files at <debugfs>/omapdss/ which show information 206There are also some debugfs files at <debugfs>/omapdss/ which show information
161about clocks and registers. 207about clocks and registers.