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Shashank Sharma 832d4f2f41 drm/edid: parse YCBCR420 videomodes from EDID
HDMI 2.0 spec adds support for YCBCR420 sub-sampled output.
CEA-861-F adds two new blocks in EDID's CEA extension blocks,
to provide information about sink's YCBCR420 output capabilities.

These blocks are:

- YCBCR420vdb(YCBCR 420 video data block):
This block contains VICs of video modes, which can be sopported only
in YCBCR420 output mode (Not in RGB/YCBCR444/422. Its like a normal
SVD block, valid for YCBCR420 modes only.

- YCBCR420cmdb(YCBCR 420 capability map data block):
This block gives information about video modes which can support
YCBCR420 output mode also (along with RGB,YCBCR444/422 etc) This
block contains a bitmap index of normal svd videomodes, which can
support YCBCR420 output too.
So if bit 0 from first vcb byte is set, first video mode in the svd
list can support YCBCR420 output too. Bit 1 means second video mode
from svd list can support YCBCR420 output too, and so on.

This patch adds two bitmaps in display's hdmi_info structure, one each
for VCB and VDB modes. If the source is HDMI 2.0 capable, this patch
adds:
- VDB modes (YCBCR 420 only modes) in connector's mode list, also makes
  an entry in the vdb_bitmap per vic.
- VCB modes (YCBCR 420 also modes) only entry in the vcb_bitmap.

Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Jose Abreu <joabreu@synopsys.com>
Cc: Emil Velikov <emil.l.velikov@gmail.com>

V2: Addressed
    Review comments from Emil:
    - Use 1ULL<<i instead of 1<<i to make sure the output is 64bit.
    - Use the suggested method for updating dbmap.
    - Add documentation for YCBCR420_vcb_map to fix kbuild warning.

    Review comments from Ville:
    - Do not expose the YCBCR420 flags in uabi layer, keep it internal.
    - Save a map of YCBCR420 modes for future reference.
    - Check db length before trying to parse extended tag.
    - Add a warning if there are > 64 modes in capability map block.
    - Use y420cmdb in function names and macros while dealing with vcb
      to be aligned with spec.
    - Move the display information parsing block ahead of mode parsing
      blocks.

V3: Addressed design/review comments from Ville
    - Do not add flags in video modes, else we have to expose them to user
    - There should not be a UABI change, and kernel should detect the
      choice of the output based on type of mode, and the bitmaps.
    - Use standard bitops from kernel bitmap header, instead of calculating
      bit positions manually.

V4: Addressed review comments from Ville:
    - s/ycbcr_420_vdb/y420vdb
    - s/ycbcr_420_vcb/y420cmdb
    - Be less verbose on description of do_y420vdb_modes
    - Move newmode variable in the loop scope.
    - Use svd_to_vic() to get a VIC, instead of 0x7f
    - Remove bitmap description for CMDB modes & VDB modes
    - Dont add connector->ycbcr_420_allowed check for cmdb modes
    - Remove 'len' variable, in is_y420cmdb function, which is used
      only once
    - Add length check in is_y420vdb function
    - Remove unnecessary if (!db) check in function parse_y420cmdb_bitmap
    - Do not add print about YCBCR 420 modes
    - Fix indentation in few places
    - Move ycbcr420_dc_modes in next patch, where its used
    - Add a separate patch for movement of drm_add_display_info()

V5: Addressed review comments from Ville:
    - Add the patch which cleans up the current EXTENDED_TAG usage
    - Make y420_cmdb_map u64
    - Do not block ycbcr420 modes while parsing the EDID, rather
      add a separate helper function to prune ycbcr420-only modes from
      connector's probed modes.

V6: Rebase
V7: Move this patch after the 420_only validation patch (Ville)
V8: Addressed review comments from Ville
    - use cea_vic_valid check before adding cmdb/vdb modes
    - add check for i < 64 while adding cmdb modes
    - use 1ULL while checking bitmap

Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1500028426-14883-1-git-send-email-shashank.sharma@intel.com
[vsyrjala: Fix checkpatch complaints and indentation]
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
2017-07-14 21:23:54 +03:00
Documentation dt-bindings: Add Pervasive Displays RePaper bindings 2017-07-14 19:29:33 +02:00
arch Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-06-25 12:01:56 -07:00
block blk-mq: fix performance regression with shared tags 2017-06-21 10:17:49 -06:00
certs scripts/spelling.txt: add "intialise(d)" pattern and fix typo instances 2017-05-08 17:15:13 -07:00
crypto crypto : asymmetric_keys : verify_pefile:zero memory content before freeing 2017-06-09 13:29:50 +10:00
drivers drm/edid: parse YCBCR420 videomodes from EDID 2017-07-14 21:23:54 +03:00
firmware firmware/Makefile: force recompilation if makefile changes 2017-05-08 17:15:10 -07:00
fs Merge branch 'akpm' (patches from Andrew) 2017-06-23 16:30:52 -07:00
include drm/edid: parse YCBCR420 videomodes from EDID 2017-07-14 21:23:54 +03:00
init Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-05-10 10:30:46 -07:00
ipc mm: introduce kv[mz]alloc helpers 2017-05-08 17:15:12 -07:00
kernel Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-06-25 11:59:19 -07:00
lib lib/cmdline.c: fix get_options() overflow while parsing ranges 2017-06-23 16:15:55 -07:00
mm slub: make sysfs file removal asynchronous 2017-06-23 16:15:55 -07:00
net igmp: add a missing spin_lock_init() 2017-06-20 15:51:57 -04:00
samples samples/bpf: run cleanup routines when receiving SIGTERM 2017-05-11 21:43:30 -04:00
scripts Kbuild fixes for v4.12 (2nd) 2017-06-24 16:18:00 -07:00
security selinux: fix double free in selinux_parse_opts_str() 2017-06-13 17:34:22 +10:00
sound Linux 4.12-rc7 2017-06-27 08:28:30 +10:00
tools perf probe: Fix probe definition for inlined functions 2017-06-22 16:08:09 -03:00
usr initramfs: fix disabling of initramfs (and its compression) 2017-06-02 15:07:37 -07:00
virt KVM: arm/arm64: Handle possible NULL stage2 pud when ageing pages 2017-06-06 15:28:40 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: Add support to generate LLVM assembly files 2017-04-25 08:13:52 +09:00
.mailmap power supply and reset changes for the v4.12 series (part 2) 2017-05-12 12:02:21 -07:00
COPYING
CREDITS avr32: remove support for AVR32 architecture 2017-05-01 09:27:15 +02:00
Kbuild kbuild: Consolidate header generation from ASM offset information 2017-04-13 05:43:37 +09:00
Kconfig
MAINTAINERS drm/tinydrm: Add RePaper e-ink driver 2017-07-14 19:30:08 +02:00
Makefile Linux 4.12-rc7 2017-06-25 18:30:05 -07:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

README

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.