Kernel Source and devicetree for NOTHING Phone(3a) and Phone(3a)Pro
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Jani Nikula dc5977da99 drm/i915: set DP Main Stream Attribute for color range on DDI platforms
Since Haswell we have no color range indication either in the pipe or
port registers for DP. Instead, there's a separate register for setting
the DP Main Stream Attributes (MSA) directly. The MSA register
definition makes no references to colorimetry, just a vague reference to
the DP spec. The connection to the color range was lost.

Apparently we've failed to set the proper MSA bit for limited, or CEA,
range ever since the first DDI platforms. We've started setting other
MSA parameters since commit dae847991a ("drm/i915: add
intel_ddi_set_pipe_settings").

Without the crucial bit of information, the DP sink has no way of
knowing the source is actually transmitting limited range RGB, leading
to "washed out" colors. With the colorimetry information, compliant
sinks should be able to handle the limited range properly. Native
(i.e. non-LSPCON) HDMI was not affected because we do pass the color
range via AVI infoframes.

Though not the root cause, the problem was made worse for DDI platforms
with commit 55bc60db59 ("drm/i915: Add "Automatic" mode for the
"Broadcast RGB" property"), which selects limited range RGB
automatically based on the mode, as per the DP, HDMI and CEA specs.

After all these years, the fix boils down to flipping one bit.

[Per testing reports, this fixes DP sinks, but not the LSPCON. My
 educated guess is that the LSPCON fails to turn the CEA range MSA into
 AVI infoframes for HDMI.]

Reported-by: Michał Kopeć <mkopec12@gmail.com>
Reported-by: N. W. <nw9165-3201@yahoo.com>
Reported-by: Nicholas Stommel <nicholas.stommel@gmail.com>
Reported-by: Tom Yan <tom.ty89@gmail.com>
Tested-by: Nicholas Stommel <nicholas.stommel@gmail.com>
References: https://bugs.freedesktop.org/show_bug.cgi?id=100023
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107476
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=94921
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v3.9+
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180814060001.18224-1-jani.nikula@intel.com
2018-08-14 16:30:39 +03:00
arch On GEM side: 2018-07-20 12:29:24 +10:00
block for-linus-20180629 2018-06-30 10:47:46 -07:00
certs certs/blacklist: fix const confusion 2018-06-26 09:43:03 -07:00
crypto Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
Documentation drm-misc-next for 4.19: 2018-07-20 10:46:49 +10:00
drivers drm/i915: set DP Main Stream Attribute for color range on DDI platforms 2018-08-14 16:30:39 +03:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs for-4.18-rc2-tag 2018-07-01 12:38:16 -07:00
include drm/i915/cfl: Add a new CFL PCI ID. 2018-08-08 22:31:05 -07:00
init Kbuild fixes for v4.18 2018-06-30 13:05:30 -07:00
ipc ipc: use new return type vm_fault_t 2018-06-15 07:55:25 +09:00
kernel drm-misc-next for 4.19: 2018-07-06 10:01:56 +10:00
lib Merge branch 'vmwgfx-next' of git://people.freedesktop.org/~thomash/linux into drm-next 2018-07-06 08:47:14 +10:00
LICENSES LICENSES: Add Linux-OpenIB license text 2018-04-27 16:41:53 -06:00
mm slub: fix failure when we delete and create a slab cache 2018-06-28 11:16:44 -07:00
net net: handle NULL ->poll gracefully 2018-06-29 06:51:51 -07:00
samples VFIO updates for v4.18 2018-06-12 13:11:26 -07:00
scripts Kbuild fixes for v4.18 2018-06-30 13:05:30 -07:00
security selinux/stable-4.18 PR 20180629 2018-06-30 11:15:12 -07:00
sound ALSA: seq: Fix UBSAN warning at SNDRV_SEQ_IOCTL_QUERY_NEXT_CLIENT ioctl 2018-06-25 11:18:04 +02:00
tools Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-30 11:42:14 -07:00
usr kbuild: rename built-in.o to built-in.a 2018-03-26 02:01:19 +09:00
virt KVM: arm64: Prevent KVM_COMPAT from being selected 2018-06-21 17:17:50 +01:00
.clang-format clang-format: add configuration file 2018-04-11 10:28:35 -07:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap Merge branch 'asoc-4.17' into asoc-4.18 for compress dependencies 2018-04-26 12:24:28 +01:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS/CREDITS: Drop METAG ARCHITECTURE 2018-03-05 16:34:24 +00:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: add basic helper macros to scripts/Kconfig.include 2018-05-29 03:31:19 +09:00
MAINTAINERS proc: add Alexey to MAINTAINERS 2018-06-28 11:16:44 -07:00
Makefile Linux 4.18-rc3 2018-07-01 16:04:53 -07:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

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

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

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.