Mhhh, one last nitpick On Thu, 2019-08-22 at 09:57 -0400, David Francis wrote: > Instead of having drm_dp_dpcd_read/write and > drm_dp_mst_dpcd_read/write as entry points into the > aux code, have drm_dp_dpcd_read/write handle both. > > This means that DRM drivers can make MST DPCD read/writes. > > v2: Fix spacing > > Cc: Leo Li <sunpeng.li@xxxxxxx> > Cc: Lyude Paul <lyude@xxxxxxxxxx> > Signed-off-by: David Francis <David.Francis@xxxxxxx> > --- > drivers/gpu/drm/drm_dp_aux_dev.c | 12 ++---------- > drivers/gpu/drm/drm_dp_helper.c | 10 ++++++++-- > 2 files changed, 10 insertions(+), 12 deletions(-) > > diff --git a/drivers/gpu/drm/drm_dp_aux_dev.c > b/drivers/gpu/drm/drm_dp_aux_dev.c > index 0cfb386754c3..418cad4f649a 100644 > --- a/drivers/gpu/drm/drm_dp_aux_dev.c > +++ b/drivers/gpu/drm/drm_dp_aux_dev.c > @@ -163,11 +163,7 @@ static ssize_t auxdev_read_iter(struct kiocb *iocb, > struct iov_iter *to) > break; > } > > - if (aux_dev->aux->is_remote) > - res = drm_dp_mst_dpcd_read(aux_dev->aux, pos, buf, > - todo); > - else > - res = drm_dp_dpcd_read(aux_dev->aux, pos, buf, todo); > + res = drm_dp_dpcd_read(aux_dev->aux, pos, buf, todo); > > if (res <= 0) > break; > @@ -215,11 +211,7 @@ static ssize_t auxdev_write_iter(struct kiocb *iocb, > struct iov_iter *from) > break; > } > > - if (aux_dev->aux->is_remote) > - res = drm_dp_mst_dpcd_write(aux_dev->aux, pos, buf, > - todo); > - else > - res = drm_dp_dpcd_write(aux_dev->aux, pos, buf, todo); > + res = drm_dp_mst_dpcd_write(aux_dev->aux, pos, buf, todo); > > if (res <= 0) > break; > diff --git a/drivers/gpu/drm/drm_dp_helper.c > b/drivers/gpu/drm/drm_dp_helper.c > index ffc68d305afe..b1599760b6a3 100644 > --- a/drivers/gpu/drm/drm_dp_helper.c > +++ b/drivers/gpu/drm/drm_dp_helper.c > @@ -30,6 +30,7 @@ > #include <linux/seq_file.h> > > #include <drm/drm_dp_helper.h> > +#include <drm/drm_dp_mst_helper.h> > #include <drm/drm_print.h> > #include <drm/drm_vblank.h> > > @@ -251,7 +252,7 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 > request, > > /** > * drm_dp_dpcd_read() - read a series of bytes from the DPCD > - * @aux: DisplayPort AUX channel > + * @aux: DisplayPort AUX channel (SST or MST) > * @offset: address of the (first) register to read > * @buffer: buffer to store the register values > * @size: number of bytes in @buffer > @@ -268,6 +269,8 @@ ssize_t drm_dp_dpcd_read(struct drm_dp_aux *aux, > unsigned int offset, > { > int ret; > > + if (aux->is_remote) > + return drm_dp_mst_dpcd_read(aux, offset, buffer, size); Let's actually replace this with if (aux->is_remote) ret = drm_dp_mst_dpcd_read(aux, offset, buffer, size); else ret = drm_dp_dpcd_access(aux, DP_AUX_NATIVE_WRITE, offset, buffer, size); That way we still call drm_dp_dump_access() so that we can log the DPCD read to the kernel log. Let's also add a space down here ⬇... > /* > * HP ZR24w corrupts the first DPCD access after entering power save > * mode. Eg. on a read, the entire buffer will be filled with the same > @@ -296,7 +299,7 @@ EXPORT_SYMBOL(drm_dp_dpcd_read); > > /** > * drm_dp_dpcd_write() - write a series of bytes to the DPCD > - * @aux: DisplayPort AUX channel > + * @aux: DisplayPort AUX channel (SST or MST) > * @offset: address of the (first) register to write > * @buffer: buffer containing the values to write > * @size: number of bytes in @buffer > @@ -313,6 +316,9 @@ ssize_t drm_dp_dpcd_write(struct drm_dp_aux *aux, > unsigned int offset, > { > int ret; > > + if (aux->is_remote) > + return drm_dp_mst_dpcd_write(aux, offset, buffer, size); > + ...and do the same thing with drm_dp_dpcd_write() that we did with drm_dp_dpcd_read() With those changes, this patch is: Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx> > ret = drm_dp_dpcd_access(aux, DP_AUX_NATIVE_WRITE, offset, buffer, > size); > drm_dp_dump_access(aux, DP_AUX_NATIVE_WRITE, offset, buffer, ret); -- Cheers, Lyude Paul _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel