[PATCH libdrm v2 0/2] Add Writeback Support for Modetest

[Rohith Iyer]

Add writeback support to modetest with the below options:

- Passing in -c will now also show the writeback connector

- Test a built-in mode on writeback connector

- Test a custom mode from user input on writeback connector
  Usage: "./modetest -M msm -x <connector_id>:<mode_parameters>
            -a -P <plane_id>@<crtc_id>:<widthxheight>+0+0 at RG24."
  Refer to --help for exact syntax

- Dump the writeback output buffer to bitstream
  Usage: "./modetest -M msm -s <connector_id>:<widthxheight>
          -a -o <filepath>
          -P <plane_id>@<crtc_id>:<widthxheight>+0+0 at RG24"

This currently supports a singular writeback connector.
This patch also fixes a bug for running modetest with the atomic flag.

Changes made in V2:
- Added helper method that checks if user pipe has writeback connector
- Added error message for dump flag if no writeback connector is found
- Polls on the writeback fence fd until writeback is complete

Rohith Iyer (2):
  tests/modetest: Allocate drmModeAtomicReq before setting properties
  tests/modetest: Add support for writeback connector

 tests/modetest/buffers.c  |  19 +++++
 tests/modetest/buffers.h  |   1 +
 tests/modetest/modetest.c | 165 +++++++++++++++++++++++++++++++++-----
 3 files changed, 165 insertions(+), 20 deletions(-)

-- 
2.17.1