search for: up_req

...eouts and causes the whole topology state to go out of sync with reality, usually resulting in the user needing to replug the entire topology in hopes that it actually fixes things. The reason for this is because the way we currently handle UP requests in MST is completely bogus. drm_dp_mst_handle_up_req() is called from drm_dp_mst_hpd_irq(), which is usually called from the driver's hotplug handler. Because we handle sending the hotplug event from this function, we actually cause the driver's hotplug handler (and in turn, all sideband transactions) to block on drm_device->mode_config.co...

...eouts and causes the whole topology state to go out of sync with reality, usually resulting in the user needing to replug the entire topology in hopes that it actually fixes things. The reason for this is because the way we currently handle UP requests in MST is completely bogus. drm_dp_mst_handle_up_req() is called from drm_dp_mst_hpd_irq(), which is usually called from the driver's hotplug handler. Because we handle sending the hotplug event from this function, we actually cause the driver's hotplug handler (and in turn, all sideband transactions) to block on drm_device->mode_config.co...

...lly grabbed under random various modesetting locks, meaning that there's no way we can just invert the &mgr->lock order and keep it locked throughout the whole process of updating the topology. Luckily there are only two workers which can modify the in-memory topology layout: drm_dp_mst_up_req_work() and drm_dp_mst_link_probe_work(), meaning as long as we prevent these two workers from traveling the topology layout in parallel with the intent of updating it we don't need to worry about grabbing &mgr->lock in these workers for reads. We only need to grab &mgr->lock in th...

This is the final portion of the large series for adding MST suspend/resume reprobing that I've been working on for quite a while now. In addition, I: * Refactored and cleaned up any code I ended up digging through in the process of understanding how some parts of these helpers worked. * Added some debugging tools along the way that I ended up needing to figure out some issues in my own

...gr->base.lock, the modesetting lock which currently only protects &mgr->base.state. This works perfectly because it allows us to avoid blocking connection_mutex unnecessarily, and we can grab this in connector detection paths since it's a ww mutex. We start by having drm_dp_mst_handle_up_req() hold this when updating ports. For drm_dp_mst_handle_link_address_port() things are a bit more complicated. As I've learned the hard way, we can grab &mgr->lock.base for everything except for port->connector. See, our normal driver probing paths end up generating this rather obvious...

...mbine redundant cases in drm_dp_encode_sideband_req() drm/dp_mst: Add sideband down request tracing + selftests drm/dp_mst: Remove PDT teardown in drm_dp_destroy_port() and refactor drm/dp_mst: Refactor drm_dp_send_enum_path_resources drm/dp_mst: Remove huge conditional in drm_dp_mst_handle_up_req() drm/dp_mst: Constify guid in drm_dp_get_mst_branch_by_guid() drm/dp_mst: Refactor drm_dp_mst_handle_up_req() drm/dp_mst: Refactor drm_dp_mst_handle_down_rep() drm/dp_mst: Destroy topology_mgr mutexes drm/dp_mst: Cleanup drm_dp_send_link_address() a bit drm/dp_mst: Refactor pdt setup/t...