1 /*
2  * Copyright 2009 Red Hat Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Ben Skeggs
23  */
24 
25 #include <drm/drmP.h>
26 #include <drm/drm_dp_helper.h>
27 
28 #include "nouveau_drm.h"
29 #include "nouveau_connector.h"
30 #include "nouveau_encoder.h"
31 #include "nouveau_crtc.h"
32 
33 static void
34 nouveau_dp_probe_oui(struct drm_device *dev, struct nvkm_i2c_aux *aux, u8 *dpcd)
35 {
36 	struct nouveau_drm *drm = nouveau_drm(dev);
37 	u8 buf[3];
38 
39 	if (!(dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_OUI_SUPPORT))
40 		return;
41 
42 	if (!nvkm_rdaux(aux, DP_SINK_OUI, buf, 3))
43 		NV_DEBUG(drm, "Sink OUI: %02hx%02hx%02hx\n",
44 			     buf[0], buf[1], buf[2]);
45 
46 	if (!nvkm_rdaux(aux, DP_BRANCH_OUI, buf, 3))
47 		NV_DEBUG(drm, "Branch OUI: %02hx%02hx%02hx\n",
48 			     buf[0], buf[1], buf[2]);
49 
50 }
51 
52 int
53 nouveau_dp_detect(struct nouveau_encoder *nv_encoder)
54 {
55 	struct drm_device *dev = nv_encoder->base.base.dev;
56 	struct nouveau_drm *drm = nouveau_drm(dev);
57 	struct nvkm_i2c_aux *aux;
58 	u8 *dpcd = nv_encoder->dp.dpcd;
59 	int ret;
60 
61 	aux = nv_encoder->aux;
62 	if (!aux)
63 		return -ENODEV;
64 
65 	ret = nvkm_rdaux(aux, DP_DPCD_REV, dpcd, 8);
66 	if (ret)
67 		return ret;
68 
69 	nv_encoder->dp.link_bw = 27000 * dpcd[1];
70 	nv_encoder->dp.link_nr = dpcd[2] & DP_MAX_LANE_COUNT_MASK;
71 
72 	NV_DEBUG(drm, "display: %dx%d dpcd 0x%02x\n",
73 		     nv_encoder->dp.link_nr, nv_encoder->dp.link_bw, dpcd[0]);
74 	NV_DEBUG(drm, "encoder: %dx%d\n",
75 		     nv_encoder->dcb->dpconf.link_nr,
76 		     nv_encoder->dcb->dpconf.link_bw);
77 
78 	if (nv_encoder->dcb->dpconf.link_nr < nv_encoder->dp.link_nr)
79 		nv_encoder->dp.link_nr = nv_encoder->dcb->dpconf.link_nr;
80 	if (nv_encoder->dcb->dpconf.link_bw < nv_encoder->dp.link_bw)
81 		nv_encoder->dp.link_bw = nv_encoder->dcb->dpconf.link_bw;
82 
83 	NV_DEBUG(drm, "maximum: %dx%d\n",
84 		     nv_encoder->dp.link_nr, nv_encoder->dp.link_bw);
85 
86 	nouveau_dp_probe_oui(dev, aux, dpcd);
87 	return 0;
88 }
89