[Added Leo Li here, since they did the auxdev work that introduced these functions] Since it seems we'll actually be doing remote DPCD read/writes in DRM drivers and not just from auxdev, maybe we should combine drm_dp_dpcd_read() with drm_dp_mst_dpcd_read() and do the same with the _write() variants? Based on previous discussions with Leo Li I remember that we can't just combine the dp_aux_dev->transfer() callbacks in struct drm_dp_aux_dev, but I don't see a reason we can't just teach drm_dp_dpcd_read/write() to work with MST aux so that we don't need two seperate functions. This should be pretty easy to do, just: /* Add a check like this at the start of drm_dp_dpcd_read(): */ ssize_t drm_dp_dpcd_read(...) { if (aux->is_remote) return drm_dp_mst_dpcd_read(...); /* ... */ } /* And in drm_dp_dpcd_write(): */ ssize_t drm_dp_dpcd_write(...) { if (aux->is_remote) return drm_dp_mst_dpcd_write(...); /* ... */ } Then just replace the manual calls to drm_dp_mst_dpcd_write() in drivers/gpu/drm/drm_dp_aux_dev.c with normal drm_dp_dpcd_read()/drm_dp_dpcd_write() calls. Thoughts? On Tue, 2019-08-20 at 15:11 -0400, David Francis wrote: > To use these functions in drm driver directories, they must be > exported > > Signed-off-by: David Francis <David.Francis@xxxxxxx> > --- > drivers/gpu/drm/drm_dp_mst_topology.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c > b/drivers/gpu/drm/drm_dp_mst_topology.c > index b40d975aec76..5d5bd42da17c 100644 > --- a/drivers/gpu/drm/drm_dp_mst_topology.c > +++ b/drivers/gpu/drm/drm_dp_mst_topology.c > @@ -1512,6 +1512,7 @@ ssize_t drm_dp_mst_dpcd_read(struct drm_dp_aux *aux, > return drm_dp_send_dpcd_read(port->mgr, port, > offset, size, buffer); > } > +EXPORT_SYMBOL(drm_dp_mst_dpcd_read); > > /** > * drm_dp_mst_dpcd_write() - write a series of bytes to the DPCD via > sideband > @@ -1535,6 +1536,7 @@ ssize_t drm_dp_mst_dpcd_write(struct drm_dp_aux *aux, > return drm_dp_send_dpcd_write(port->mgr, port, > offset, size, buffer); > } > +EXPORT_SYMBOL(drm_dp_mst_dpcd_write); > > static void drm_dp_check_mstb_guid(struct drm_dp_mst_branch *mstb, u8 > *guid) > { -- Cheers, Lyude Paul _______________________________________________ amd-gfx mailing list amd-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/amd-gfx