forked from luck/tmp_suning_uos_patched
a1d926527b
According to DP spec (2.9.3.1 of DP 1.4) if EXTENDED_RECEIVER_CAPABILITY_FIELD_PRESENT is set the addresses in DPCD 02200h through 0220Fh shall contain the DPRX's true capability. These values will match 00000h through 0000Fh, except for DPCD_REV, MAX_LINK_RATE, DOWN_STREAM_PORT_PRESENT. Read from DPCD once for all 3 values as this is an expensive operation. Spec mentions that all of address space 02200h through 0220Fh should contain the right information however currently only 3 values can differ. There is no address space in the intel_dp->dpcd struct for addresses 02200h through 0220Fh, and since so much of the data is a identical, simply overwrite the values stored in 00000h through 0000Fh with the values that can be overwritten from addresses 02200h through 0220Fh. This patch helps with backward compatibility for devices pre DP1.3. v2: read only dpcd values which can be affected, remove incorrect check, split into drm include changes into separate patch, commit message, verbose debugging statements during overwrite. v3: white space fixes v4: make path dependent on DPCD revision > 1.2 v5: split into function, removed DPCD rev check v6: add debugging prints for early exit conditions v7 (From Manasi): * Memcpy, memcmp and debig logging based on sizeof(dpcd_ext) (Jani N) * Exit early (Jani N) v8 (From Manasi): * Get rid of superfluous debug prints (Jani N) * Print entire base DPCD before memcpy (Jani N) v9 (From Manasi): * Add uniform newlines (Rodrigo) Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Ville Syrjala <ville.syrjala@linux.intel.com> Signed-off-by: Matt Atwood <matthew.s.atwood@intel.com> Signed-off-by: Manasi Navare <manasi.d.navare@intel.com> Tested-by: Manasi Navare <manasi.d.navare@intel.com> Acked-by: Manasi Navare <manasi.d.navare@intel.com> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20181129220058.19636-1-manasi.d.navare@intel.com |
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| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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.
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.