linux/drivers/gpu/drm/nouveau/nouveau_dp.c
Ben Skeggs 52aa30f252 drm/nouveau/kms/nv50: switch mst sink back into sst mode
Sometimes we load with a sink already in MST mode.  If, however, we can't
or don't want to use MST, we need to be able to switch it back to SST.

This commit instantiates a stub topology manager for any output path that
we believe (the detection of this could use some improvement) has support
for MST, and adds the connector detect() logic for detecting sink support
and switching between modes.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
2016-11-07 14:04:50 +10:00

96 lines
2.9 KiB
C

/*
* Copyright 2009 Red Hat Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Authors: Ben Skeggs
*/
#include <drm/drmP.h>
#include <drm/drm_dp_helper.h>
#include "nouveau_drv.h"
#include "nouveau_connector.h"
#include "nouveau_encoder.h"
#include "nouveau_crtc.h"
#include <nvif/class.h>
#include <nvif/cl5070.h>
static void
nouveau_dp_probe_oui(struct drm_device *dev, struct nvkm_i2c_aux *aux, u8 *dpcd)
{
struct nouveau_drm *drm = nouveau_drm(dev);
u8 buf[3];
if (!(dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_OUI_SUPPORT))
return;
if (!nvkm_rdaux(aux, DP_SINK_OUI, buf, 3))
NV_DEBUG(drm, "Sink OUI: %02hx%02hx%02hx\n",
buf[0], buf[1], buf[2]);
if (!nvkm_rdaux(aux, DP_BRANCH_OUI, buf, 3))
NV_DEBUG(drm, "Branch OUI: %02hx%02hx%02hx\n",
buf[0], buf[1], buf[2]);
}
int
nouveau_dp_detect(struct nouveau_encoder *nv_encoder)
{
struct drm_device *dev = nv_encoder->base.base.dev;
struct nouveau_drm *drm = nouveau_drm(dev);
struct nvkm_i2c_aux *aux;
u8 *dpcd = nv_encoder->dp.dpcd;
int ret;
aux = nv_encoder->aux;
if (!aux)
return -ENODEV;
ret = nvkm_rdaux(aux, DP_DPCD_REV, dpcd, 8);
if (ret)
return ret;
nv_encoder->dp.link_bw = 27000 * dpcd[1];
nv_encoder->dp.link_nr = dpcd[2] & DP_MAX_LANE_COUNT_MASK;
NV_DEBUG(drm, "display: %dx%d dpcd 0x%02x\n",
nv_encoder->dp.link_nr, nv_encoder->dp.link_bw, dpcd[0]);
NV_DEBUG(drm, "encoder: %dx%d\n",
nv_encoder->dcb->dpconf.link_nr,
nv_encoder->dcb->dpconf.link_bw);
if (nv_encoder->dcb->dpconf.link_nr < nv_encoder->dp.link_nr)
nv_encoder->dp.link_nr = nv_encoder->dcb->dpconf.link_nr;
if (nv_encoder->dcb->dpconf.link_bw < nv_encoder->dp.link_bw)
nv_encoder->dp.link_bw = nv_encoder->dcb->dpconf.link_bw;
NV_DEBUG(drm, "maximum: %dx%d\n",
nv_encoder->dp.link_nr, nv_encoder->dp.link_bw);
nouveau_dp_probe_oui(dev, aux, dpcd);
ret = nv50_mstm_detect(nv_encoder->dp.mstm, dpcd, 0);
if (ret == 0)
return NOUVEAU_DP_SST;
return ret;
}