On Thu, 23 Jan 2025, Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> wrote: > On Fri, Jan 17, 2025 at 10:56:35AM +0200, Dmitry Baryshkov wrote: >> Existing DPCD access functions return an error code or the number of >> bytes being read / write in case of partial access. However a lot of >> drivers either (incorrectly) ignore partial access or mishandle error >> codes. In other cases this results in a boilerplate code which compares >> returned value with the size. >> >> As suggested by Jani implement new set of DPCD access helpers, which >> ignore partial access, always return 0 or an error code. Reimplement >> existing helpers using the new functions to ensure backwards >> compatibility. >> >> This series targets only the DRM helpers code. If the approach is found >> to be acceptable, each of the drivers should be converted on its own. > > Gracious ping for the series, it's been posted a week ago. It's a bit of a bummer the names become longer. I don't have a better suggestion, though. I do like it that the error handling becomes easier and more uniform overall, and this actually fixes many places that only checked for < 0 with the old functions. I glanced through the series, I didn't spot anything obviously wrong, but didn't do a thorough review either. I can do once we have wider buy-in for the idea in general, so the effort won't be wasted. For now, Acked-by: Jani Nikula <jani.nikula@xxxxxxxxx> > >> >> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> >> --- >> Dmitry Baryshkov (7): >> drm/display: dp: change drm_dp_dpcd_read_link_status() return >> drm/display: dp: implement new access helpers >> drm/display: dp: use new DCPD access helpers >> drm/display: dp-aux-dev: use new DCPD access helpers >> drm/display: dp-cec: use new DCPD access helpers >> drm/display: dp-mst-topology: use new DCPD access helpers >> drm/display: dp-tunnel: use new DCPD access helpers >> >> drivers/gpu/drm/display/drm_dp_aux_dev.c | 12 +- >> drivers/gpu/drm/display/drm_dp_cec.c | 37 ++- >> drivers/gpu/drm/display/drm_dp_helper.c | 345 +++++++++++--------------- >> drivers/gpu/drm/display/drm_dp_mst_topology.c | 132 +++++----- >> drivers/gpu/drm/display/drm_dp_tunnel.c | 20 +- >> drivers/gpu/drm/msm/dp/dp_ctrl.c | 45 ++-- >> drivers/gpu/drm/msm/dp/dp_link.c | 17 +- >> include/drm/display/drm_dp_helper.h | 81 +++++- >> include/drm/display/drm_dp_mst_helper.h | 10 +- >> 9 files changed, 354 insertions(+), 345 deletions(-) >> --- >> base-commit: 440aaf479c9aaf5ecea9a463eb826ec243d5f1cf >> change-id: 20241231-drm-rework-dpcd-access-b0fc2e47d613 >> >> Best regards, >> -- >> Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> >> -- Jani Nikula, Intel
