2 * Copyright © 2014 Red Hat
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
7 * notice and this permission notice appear in supporting documentation, and
8 * that the name of the copyright holders not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission. The copyright holders make no representations
11 * about the suitability of this software for any purpose. It is provided "as
12 * is" without express or implied warranty.
14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
23 #include <linux/kernel.h>
24 #include <linux/delay.h>
25 #include <linux/init.h>
26 #include <linux/errno.h>
27 #include <linux/sched.h>
28 #include <linux/seq_file.h>
29 #include <linux/i2c.h>
30 #include <drm/drm_dp_mst_helper.h>
33 #include <drm/drm_fixed.h>
38 * These functions contain parts of the DisplayPort 1.2a MultiStream Transport
39 * protocol. The helpers contain a topology manager and bandwidth manager.
40 * The helpers encapsulate the sending and received of sideband msgs.
42 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr
*mgr
,
44 static int test_calc_pbn_mode(void);
46 static void drm_dp_put_port(struct drm_dp_mst_port
*port
);
48 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr
*mgr
,
50 struct drm_dp_payload
*payload
);
52 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr
*mgr
,
53 struct drm_dp_mst_port
*port
,
54 int offset
, int size
, u8
*bytes
);
56 static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr
*mgr
,
57 struct drm_dp_mst_branch
*mstb
);
58 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr
*mgr
,
59 struct drm_dp_mst_branch
*mstb
,
60 struct drm_dp_mst_port
*port
);
61 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr
*mgr
,
64 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux
*aux
);
65 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux
*aux
);
66 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr
*mgr
);
67 /* sideband msg handling */
68 static u8
drm_dp_msg_header_crc4(const uint8_t *data
, size_t num_nibbles
)
73 int number_of_bits
= num_nibbles
* 4;
76 while (number_of_bits
!= 0) {
79 remainder
|= (data
[array_index
] & bitmask
) >> bitshift
;
87 if ((remainder
& 0x10) == 0x10)
92 while (number_of_bits
!= 0) {
95 if ((remainder
& 0x10) != 0)
102 static u8
drm_dp_msg_data_crc4(const uint8_t *data
, u8 number_of_bytes
)
107 int number_of_bits
= number_of_bytes
* 8;
110 while (number_of_bits
!= 0) {
113 remainder
|= (data
[array_index
] & bitmask
) >> bitshift
;
121 if ((remainder
& 0x100) == 0x100)
126 while (number_of_bits
!= 0) {
129 if ((remainder
& 0x100) != 0)
133 return remainder
& 0xff;
135 static inline u8
drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr
*hdr
)
138 size
+= (hdr
->lct
/ 2);
142 static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr
*hdr
,
148 buf
[idx
++] = ((hdr
->lct
& 0xf) << 4) | (hdr
->lcr
& 0xf);
149 for (i
= 0; i
< (hdr
->lct
/ 2); i
++)
150 buf
[idx
++] = hdr
->rad
[i
];
151 buf
[idx
++] = (hdr
->broadcast
<< 7) | (hdr
->path_msg
<< 6) |
152 (hdr
->msg_len
& 0x3f);
153 buf
[idx
++] = (hdr
->somt
<< 7) | (hdr
->eomt
<< 6) | (hdr
->seqno
<< 4);
155 crc4
= drm_dp_msg_header_crc4(buf
, (idx
* 2) - 1);
156 buf
[idx
- 1] |= (crc4
& 0xf);
161 static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr
*hdr
,
162 u8
*buf
, int buflen
, u8
*hdrlen
)
171 len
+= ((buf
[0] & 0xf0) >> 4) / 2;
174 crc4
= drm_dp_msg_header_crc4(buf
, (len
* 2) - 1);
176 if ((crc4
& 0xf) != (buf
[len
- 1] & 0xf)) {
177 DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4
, buf
[len
- 1]);
181 hdr
->lct
= (buf
[0] & 0xf0) >> 4;
182 hdr
->lcr
= (buf
[0] & 0xf);
184 for (i
= 0; i
< (hdr
->lct
/ 2); i
++)
185 hdr
->rad
[i
] = buf
[idx
++];
186 hdr
->broadcast
= (buf
[idx
] >> 7) & 0x1;
187 hdr
->path_msg
= (buf
[idx
] >> 6) & 0x1;
188 hdr
->msg_len
= buf
[idx
] & 0x3f;
190 hdr
->somt
= (buf
[idx
] >> 7) & 0x1;
191 hdr
->eomt
= (buf
[idx
] >> 6) & 0x1;
192 hdr
->seqno
= (buf
[idx
] >> 4) & 0x1;
198 static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body
*req
,
199 struct drm_dp_sideband_msg_tx
*raw
)
204 buf
[idx
++] = req
->req_type
& 0x7f;
206 switch (req
->req_type
) {
207 case DP_ENUM_PATH_RESOURCES
:
208 buf
[idx
] = (req
->u
.port_num
.port_number
& 0xf) << 4;
211 case DP_ALLOCATE_PAYLOAD
:
212 buf
[idx
] = (req
->u
.allocate_payload
.port_number
& 0xf) << 4 |
213 (req
->u
.allocate_payload
.number_sdp_streams
& 0xf);
215 buf
[idx
] = (req
->u
.allocate_payload
.vcpi
& 0x7f);
217 buf
[idx
] = (req
->u
.allocate_payload
.pbn
>> 8);
219 buf
[idx
] = (req
->u
.allocate_payload
.pbn
& 0xff);
221 for (i
= 0; i
< req
->u
.allocate_payload
.number_sdp_streams
/ 2; i
++) {
222 buf
[idx
] = ((req
->u
.allocate_payload
.sdp_stream_sink
[i
* 2] & 0xf) << 4) |
223 (req
->u
.allocate_payload
.sdp_stream_sink
[i
* 2 + 1] & 0xf);
226 if (req
->u
.allocate_payload
.number_sdp_streams
& 1) {
227 i
= req
->u
.allocate_payload
.number_sdp_streams
- 1;
228 buf
[idx
] = (req
->u
.allocate_payload
.sdp_stream_sink
[i
] & 0xf) << 4;
232 case DP_QUERY_PAYLOAD
:
233 buf
[idx
] = (req
->u
.query_payload
.port_number
& 0xf) << 4;
235 buf
[idx
] = (req
->u
.query_payload
.vcpi
& 0x7f);
238 case DP_REMOTE_DPCD_READ
:
239 buf
[idx
] = (req
->u
.dpcd_read
.port_number
& 0xf) << 4;
240 buf
[idx
] |= ((req
->u
.dpcd_read
.dpcd_address
& 0xf0000) >> 16) & 0xf;
242 buf
[idx
] = (req
->u
.dpcd_read
.dpcd_address
& 0xff00) >> 8;
244 buf
[idx
] = (req
->u
.dpcd_read
.dpcd_address
& 0xff);
246 buf
[idx
] = (req
->u
.dpcd_read
.num_bytes
);
250 case DP_REMOTE_DPCD_WRITE
:
251 buf
[idx
] = (req
->u
.dpcd_write
.port_number
& 0xf) << 4;
252 buf
[idx
] |= ((req
->u
.dpcd_write
.dpcd_address
& 0xf0000) >> 16) & 0xf;
254 buf
[idx
] = (req
->u
.dpcd_write
.dpcd_address
& 0xff00) >> 8;
256 buf
[idx
] = (req
->u
.dpcd_write
.dpcd_address
& 0xff);
258 buf
[idx
] = (req
->u
.dpcd_write
.num_bytes
);
260 memcpy(&buf
[idx
], req
->u
.dpcd_write
.bytes
, req
->u
.dpcd_write
.num_bytes
);
261 idx
+= req
->u
.dpcd_write
.num_bytes
;
263 case DP_REMOTE_I2C_READ
:
264 buf
[idx
] = (req
->u
.i2c_read
.port_number
& 0xf) << 4;
265 buf
[idx
] |= (req
->u
.i2c_read
.num_transactions
& 0x3);
267 for (i
= 0; i
< (req
->u
.i2c_read
.num_transactions
& 0x3); i
++) {
268 buf
[idx
] = req
->u
.i2c_read
.transactions
[i
].i2c_dev_id
& 0x7f;
270 buf
[idx
] = req
->u
.i2c_read
.transactions
[i
].num_bytes
;
272 memcpy(&buf
[idx
], req
->u
.i2c_read
.transactions
[i
].bytes
, req
->u
.i2c_read
.transactions
[i
].num_bytes
);
273 idx
+= req
->u
.i2c_read
.transactions
[i
].num_bytes
;
275 buf
[idx
] = (req
->u
.i2c_read
.transactions
[i
].no_stop_bit
& 0x1) << 5;
276 buf
[idx
] |= (req
->u
.i2c_read
.transactions
[i
].i2c_transaction_delay
& 0xf);
279 buf
[idx
] = (req
->u
.i2c_read
.read_i2c_device_id
) & 0x7f;
281 buf
[idx
] = (req
->u
.i2c_read
.num_bytes_read
);
285 case DP_REMOTE_I2C_WRITE
:
286 buf
[idx
] = (req
->u
.i2c_write
.port_number
& 0xf) << 4;
288 buf
[idx
] = (req
->u
.i2c_write
.write_i2c_device_id
) & 0x7f;
290 buf
[idx
] = (req
->u
.i2c_write
.num_bytes
);
292 memcpy(&buf
[idx
], req
->u
.i2c_write
.bytes
, req
->u
.i2c_write
.num_bytes
);
293 idx
+= req
->u
.i2c_write
.num_bytes
;
299 static void drm_dp_crc_sideband_chunk_req(u8
*msg
, u8 len
)
302 crc4
= drm_dp_msg_data_crc4(msg
, len
);
306 static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body
*rep
,
307 struct drm_dp_sideband_msg_tx
*raw
)
312 buf
[idx
++] = (rep
->reply_type
& 0x1) << 7 | (rep
->req_type
& 0x7f);
317 /* this adds a chunk of msg to the builder to get the final msg */
318 static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx
*msg
,
319 u8
*replybuf
, u8 replybuflen
, bool hdr
)
326 struct drm_dp_sideband_msg_hdr recv_hdr
;
327 ret
= drm_dp_decode_sideband_msg_hdr(&recv_hdr
, replybuf
, replybuflen
, &hdrlen
);
329 print_hex_dump(KERN_DEBUG
, "failed hdr", DUMP_PREFIX_NONE
, 16, 1, replybuf
, replybuflen
, false);
333 /* get length contained in this portion */
334 msg
->curchunk_len
= recv_hdr
.msg_len
;
335 msg
->curchunk_hdrlen
= hdrlen
;
337 /* we have already gotten an somt - don't bother parsing */
338 if (recv_hdr
.somt
&& msg
->have_somt
)
342 memcpy(&msg
->initial_hdr
, &recv_hdr
, sizeof(struct drm_dp_sideband_msg_hdr
));
343 msg
->have_somt
= true;
346 msg
->have_eomt
= true;
348 /* copy the bytes for the remainder of this header chunk */
349 msg
->curchunk_idx
= min(msg
->curchunk_len
, (u8
)(replybuflen
- hdrlen
));
350 memcpy(&msg
->chunk
[0], replybuf
+ hdrlen
, msg
->curchunk_idx
);
352 memcpy(&msg
->chunk
[msg
->curchunk_idx
], replybuf
, replybuflen
);
353 msg
->curchunk_idx
+= replybuflen
;
356 if (msg
->curchunk_idx
>= msg
->curchunk_len
) {
358 crc4
= drm_dp_msg_data_crc4(msg
->chunk
, msg
->curchunk_len
- 1);
359 /* copy chunk into bigger msg */
360 memcpy(&msg
->msg
[msg
->curlen
], msg
->chunk
, msg
->curchunk_len
- 1);
361 msg
->curlen
+= msg
->curchunk_len
- 1;
366 static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx
*raw
,
367 struct drm_dp_sideband_msg_reply_body
*repmsg
)
371 memcpy(repmsg
->u
.link_addr
.guid
, &raw
->msg
[idx
], 16);
373 repmsg
->u
.link_addr
.nports
= raw
->msg
[idx
] & 0xf;
375 if (idx
> raw
->curlen
)
377 for (i
= 0; i
< repmsg
->u
.link_addr
.nports
; i
++) {
378 if (raw
->msg
[idx
] & 0x80)
379 repmsg
->u
.link_addr
.ports
[i
].input_port
= 1;
381 repmsg
->u
.link_addr
.ports
[i
].peer_device_type
= (raw
->msg
[idx
] >> 4) & 0x7;
382 repmsg
->u
.link_addr
.ports
[i
].port_number
= (raw
->msg
[idx
] & 0xf);
385 if (idx
> raw
->curlen
)
387 repmsg
->u
.link_addr
.ports
[i
].mcs
= (raw
->msg
[idx
] >> 7) & 0x1;
388 repmsg
->u
.link_addr
.ports
[i
].ddps
= (raw
->msg
[idx
] >> 6) & 0x1;
389 if (repmsg
->u
.link_addr
.ports
[i
].input_port
== 0)
390 repmsg
->u
.link_addr
.ports
[i
].legacy_device_plug_status
= (raw
->msg
[idx
] >> 5) & 0x1;
392 if (idx
> raw
->curlen
)
394 if (repmsg
->u
.link_addr
.ports
[i
].input_port
== 0) {
395 repmsg
->u
.link_addr
.ports
[i
].dpcd_revision
= (raw
->msg
[idx
]);
397 if (idx
> raw
->curlen
)
399 memcpy(repmsg
->u
.link_addr
.ports
[i
].peer_guid
, &raw
->msg
[idx
], 16);
401 if (idx
> raw
->curlen
)
403 repmsg
->u
.link_addr
.ports
[i
].num_sdp_streams
= (raw
->msg
[idx
] >> 4) & 0xf;
404 repmsg
->u
.link_addr
.ports
[i
].num_sdp_stream_sinks
= (raw
->msg
[idx
] & 0xf);
408 if (idx
> raw
->curlen
)
414 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx
, raw
->curlen
);
418 static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx
*raw
,
419 struct drm_dp_sideband_msg_reply_body
*repmsg
)
422 repmsg
->u
.remote_dpcd_read_ack
.port_number
= raw
->msg
[idx
] & 0xf;
424 if (idx
> raw
->curlen
)
426 repmsg
->u
.remote_dpcd_read_ack
.num_bytes
= raw
->msg
[idx
];
427 if (idx
> raw
->curlen
)
430 memcpy(repmsg
->u
.remote_dpcd_read_ack
.bytes
, &raw
->msg
[idx
], repmsg
->u
.remote_dpcd_read_ack
.num_bytes
);
433 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx
, raw
->curlen
);
437 static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx
*raw
,
438 struct drm_dp_sideband_msg_reply_body
*repmsg
)
441 repmsg
->u
.remote_dpcd_write_ack
.port_number
= raw
->msg
[idx
] & 0xf;
443 if (idx
> raw
->curlen
)
447 DRM_DEBUG_KMS("parse length fail %d %d\n", idx
, raw
->curlen
);
451 static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx
*raw
,
452 struct drm_dp_sideband_msg_reply_body
*repmsg
)
456 repmsg
->u
.remote_i2c_read_ack
.port_number
= (raw
->msg
[idx
] & 0xf);
458 if (idx
> raw
->curlen
)
460 repmsg
->u
.remote_i2c_read_ack
.num_bytes
= raw
->msg
[idx
];
463 memcpy(repmsg
->u
.remote_i2c_read_ack
.bytes
, &raw
->msg
[idx
], repmsg
->u
.remote_i2c_read_ack
.num_bytes
);
466 DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx
, raw
->curlen
);
470 static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx
*raw
,
471 struct drm_dp_sideband_msg_reply_body
*repmsg
)
474 repmsg
->u
.path_resources
.port_number
= (raw
->msg
[idx
] >> 4) & 0xf;
476 if (idx
> raw
->curlen
)
478 repmsg
->u
.path_resources
.full_payload_bw_number
= (raw
->msg
[idx
] << 8) | (raw
->msg
[idx
+1]);
480 if (idx
> raw
->curlen
)
482 repmsg
->u
.path_resources
.avail_payload_bw_number
= (raw
->msg
[idx
] << 8) | (raw
->msg
[idx
+1]);
484 if (idx
> raw
->curlen
)
488 DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx
, raw
->curlen
);
492 static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx
*raw
,
493 struct drm_dp_sideband_msg_reply_body
*repmsg
)
496 repmsg
->u
.allocate_payload
.port_number
= (raw
->msg
[idx
] >> 4) & 0xf;
498 if (idx
> raw
->curlen
)
500 repmsg
->u
.allocate_payload
.vcpi
= raw
->msg
[idx
];
502 if (idx
> raw
->curlen
)
504 repmsg
->u
.allocate_payload
.allocated_pbn
= (raw
->msg
[idx
] << 8) | (raw
->msg
[idx
+1]);
506 if (idx
> raw
->curlen
)
510 DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx
, raw
->curlen
);
514 static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx
*raw
,
515 struct drm_dp_sideband_msg_reply_body
*repmsg
)
518 repmsg
->u
.query_payload
.port_number
= (raw
->msg
[idx
] >> 4) & 0xf;
520 if (idx
> raw
->curlen
)
522 repmsg
->u
.query_payload
.allocated_pbn
= (raw
->msg
[idx
] << 8) | (raw
->msg
[idx
+ 1]);
524 if (idx
> raw
->curlen
)
528 DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx
, raw
->curlen
);
532 static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx
*raw
,
533 struct drm_dp_sideband_msg_reply_body
*msg
)
535 memset(msg
, 0, sizeof(*msg
));
536 msg
->reply_type
= (raw
->msg
[0] & 0x80) >> 7;
537 msg
->req_type
= (raw
->msg
[0] & 0x7f);
539 if (msg
->reply_type
) {
540 memcpy(msg
->u
.nak
.guid
, &raw
->msg
[1], 16);
541 msg
->u
.nak
.reason
= raw
->msg
[17];
542 msg
->u
.nak
.nak_data
= raw
->msg
[18];
546 switch (msg
->req_type
) {
547 case DP_LINK_ADDRESS
:
548 return drm_dp_sideband_parse_link_address(raw
, msg
);
549 case DP_QUERY_PAYLOAD
:
550 return drm_dp_sideband_parse_query_payload_ack(raw
, msg
);
551 case DP_REMOTE_DPCD_READ
:
552 return drm_dp_sideband_parse_remote_dpcd_read(raw
, msg
);
553 case DP_REMOTE_DPCD_WRITE
:
554 return drm_dp_sideband_parse_remote_dpcd_write(raw
, msg
);
555 case DP_REMOTE_I2C_READ
:
556 return drm_dp_sideband_parse_remote_i2c_read_ack(raw
, msg
);
557 case DP_ENUM_PATH_RESOURCES
:
558 return drm_dp_sideband_parse_enum_path_resources_ack(raw
, msg
);
559 case DP_ALLOCATE_PAYLOAD
:
560 return drm_dp_sideband_parse_allocate_payload_ack(raw
, msg
);
562 DRM_ERROR("Got unknown reply 0x%02x\n", msg
->req_type
);
567 static bool drm_dp_sideband_parse_connection_status_notify(struct drm_dp_sideband_msg_rx
*raw
,
568 struct drm_dp_sideband_msg_req_body
*msg
)
572 msg
->u
.conn_stat
.port_number
= (raw
->msg
[idx
] & 0xf0) >> 4;
574 if (idx
> raw
->curlen
)
577 memcpy(msg
->u
.conn_stat
.guid
, &raw
->msg
[idx
], 16);
579 if (idx
> raw
->curlen
)
582 msg
->u
.conn_stat
.legacy_device_plug_status
= (raw
->msg
[idx
] >> 6) & 0x1;
583 msg
->u
.conn_stat
.displayport_device_plug_status
= (raw
->msg
[idx
] >> 5) & 0x1;
584 msg
->u
.conn_stat
.message_capability_status
= (raw
->msg
[idx
] >> 4) & 0x1;
585 msg
->u
.conn_stat
.input_port
= (raw
->msg
[idx
] >> 3) & 0x1;
586 msg
->u
.conn_stat
.peer_device_type
= (raw
->msg
[idx
] & 0x7);
590 DRM_DEBUG_KMS("connection status reply parse length fail %d %d\n", idx
, raw
->curlen
);
594 static bool drm_dp_sideband_parse_resource_status_notify(struct drm_dp_sideband_msg_rx
*raw
,
595 struct drm_dp_sideband_msg_req_body
*msg
)
599 msg
->u
.resource_stat
.port_number
= (raw
->msg
[idx
] & 0xf0) >> 4;
601 if (idx
> raw
->curlen
)
604 memcpy(msg
->u
.resource_stat
.guid
, &raw
->msg
[idx
], 16);
606 if (idx
> raw
->curlen
)
609 msg
->u
.resource_stat
.available_pbn
= (raw
->msg
[idx
] << 8) | (raw
->msg
[idx
+ 1]);
613 DRM_DEBUG_KMS("resource status reply parse length fail %d %d\n", idx
, raw
->curlen
);
617 static bool drm_dp_sideband_parse_req(struct drm_dp_sideband_msg_rx
*raw
,
618 struct drm_dp_sideband_msg_req_body
*msg
)
620 memset(msg
, 0, sizeof(*msg
));
621 msg
->req_type
= (raw
->msg
[0] & 0x7f);
623 switch (msg
->req_type
) {
624 case DP_CONNECTION_STATUS_NOTIFY
:
625 return drm_dp_sideband_parse_connection_status_notify(raw
, msg
);
626 case DP_RESOURCE_STATUS_NOTIFY
:
627 return drm_dp_sideband_parse_resource_status_notify(raw
, msg
);
629 DRM_ERROR("Got unknown request 0x%02x\n", msg
->req_type
);
634 static int build_dpcd_write(struct drm_dp_sideband_msg_tx
*msg
, u8 port_num
, u32 offset
, u8 num_bytes
, u8
*bytes
)
636 struct drm_dp_sideband_msg_req_body req
;
638 req
.req_type
= DP_REMOTE_DPCD_WRITE
;
639 req
.u
.dpcd_write
.port_number
= port_num
;
640 req
.u
.dpcd_write
.dpcd_address
= offset
;
641 req
.u
.dpcd_write
.num_bytes
= num_bytes
;
642 req
.u
.dpcd_write
.bytes
= bytes
;
643 drm_dp_encode_sideband_req(&req
, msg
);
648 static int build_link_address(struct drm_dp_sideband_msg_tx
*msg
)
650 struct drm_dp_sideband_msg_req_body req
;
652 req
.req_type
= DP_LINK_ADDRESS
;
653 drm_dp_encode_sideband_req(&req
, msg
);
657 static int build_enum_path_resources(struct drm_dp_sideband_msg_tx
*msg
, int port_num
)
659 struct drm_dp_sideband_msg_req_body req
;
661 req
.req_type
= DP_ENUM_PATH_RESOURCES
;
662 req
.u
.port_num
.port_number
= port_num
;
663 drm_dp_encode_sideband_req(&req
, msg
);
664 msg
->path_msg
= true;
668 static int build_allocate_payload(struct drm_dp_sideband_msg_tx
*msg
, int port_num
,
669 u8 vcpi
, uint16_t pbn
)
671 struct drm_dp_sideband_msg_req_body req
;
672 memset(&req
, 0, sizeof(req
));
673 req
.req_type
= DP_ALLOCATE_PAYLOAD
;
674 req
.u
.allocate_payload
.port_number
= port_num
;
675 req
.u
.allocate_payload
.vcpi
= vcpi
;
676 req
.u
.allocate_payload
.pbn
= pbn
;
677 drm_dp_encode_sideband_req(&req
, msg
);
678 msg
->path_msg
= true;
682 static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr
*mgr
,
683 struct drm_dp_vcpi
*vcpi
)
687 mutex_lock(&mgr
->payload_lock
);
688 ret
= find_first_zero_bit(&mgr
->payload_mask
, mgr
->max_payloads
+ 1);
689 if (ret
> mgr
->max_payloads
) {
691 DRM_DEBUG_KMS("out of payload ids %d\n", ret
);
695 vcpi_ret
= find_first_zero_bit(&mgr
->vcpi_mask
, mgr
->max_payloads
+ 1);
696 if (vcpi_ret
> mgr
->max_payloads
) {
698 DRM_DEBUG_KMS("out of vcpi ids %d\n", ret
);
702 set_bit(ret
, &mgr
->payload_mask
);
703 set_bit(vcpi_ret
, &mgr
->vcpi_mask
);
704 vcpi
->vcpi
= vcpi_ret
+ 1;
705 mgr
->proposed_vcpis
[ret
- 1] = vcpi
;
707 mutex_unlock(&mgr
->payload_lock
);
711 static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr
*mgr
,
718 mutex_lock(&mgr
->payload_lock
);
719 DRM_DEBUG_KMS("putting payload %d\n", vcpi
);
720 clear_bit(vcpi
- 1, &mgr
->vcpi_mask
);
722 for (i
= 0; i
< mgr
->max_payloads
; i
++) {
723 if (mgr
->proposed_vcpis
[i
])
724 if (mgr
->proposed_vcpis
[i
]->vcpi
== vcpi
) {
725 mgr
->proposed_vcpis
[i
] = NULL
;
726 clear_bit(i
+ 1, &mgr
->payload_mask
);
729 mutex_unlock(&mgr
->payload_lock
);
732 static bool check_txmsg_state(struct drm_dp_mst_topology_mgr
*mgr
,
733 struct drm_dp_sideband_msg_tx
*txmsg
)
736 mutex_lock(&mgr
->qlock
);
737 ret
= (txmsg
->state
== DRM_DP_SIDEBAND_TX_RX
||
738 txmsg
->state
== DRM_DP_SIDEBAND_TX_TIMEOUT
);
739 mutex_unlock(&mgr
->qlock
);
743 static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch
*mstb
,
744 struct drm_dp_sideband_msg_tx
*txmsg
)
746 struct drm_dp_mst_topology_mgr
*mgr
= mstb
->mgr
;
749 ret
= wait_event_timeout(mgr
->tx_waitq
,
750 check_txmsg_state(mgr
, txmsg
),
752 mutex_lock(&mstb
->mgr
->qlock
);
754 if (txmsg
->state
== DRM_DP_SIDEBAND_TX_TIMEOUT
) {
759 DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg
, txmsg
->state
, txmsg
->seqno
);
761 /* dump some state */
765 if (txmsg
->state
== DRM_DP_SIDEBAND_TX_QUEUED
||
766 txmsg
->state
== DRM_DP_SIDEBAND_TX_START_SEND
) {
767 list_del(&txmsg
->next
);
770 if (txmsg
->state
== DRM_DP_SIDEBAND_TX_START_SEND
||
771 txmsg
->state
== DRM_DP_SIDEBAND_TX_SENT
) {
772 mstb
->tx_slots
[txmsg
->seqno
] = NULL
;
776 mutex_unlock(&mgr
->qlock
);
781 static struct drm_dp_mst_branch
*drm_dp_add_mst_branch_device(u8 lct
, u8
*rad
)
783 struct drm_dp_mst_branch
*mstb
;
785 mstb
= kzalloc(sizeof(*mstb
), GFP_KERNEL
);
791 memcpy(mstb
->rad
, rad
, lct
/ 2);
792 INIT_LIST_HEAD(&mstb
->ports
);
793 kref_init(&mstb
->kref
);
797 static void drm_dp_destroy_mst_branch_device(struct kref
*kref
)
799 struct drm_dp_mst_branch
*mstb
= container_of(kref
, struct drm_dp_mst_branch
, kref
);
800 struct drm_dp_mst_port
*port
, *tmp
;
801 bool wake_tx
= false;
803 cancel_work_sync(&mstb
->mgr
->work
);
806 * destroy all ports - don't need lock
807 * as there are no more references to the mst branch
808 * device at this point.
810 list_for_each_entry_safe(port
, tmp
, &mstb
->ports
, next
) {
811 list_del(&port
->next
);
812 drm_dp_put_port(port
);
815 /* drop any tx slots msg */
816 mutex_lock(&mstb
->mgr
->qlock
);
817 if (mstb
->tx_slots
[0]) {
818 mstb
->tx_slots
[0]->state
= DRM_DP_SIDEBAND_TX_TIMEOUT
;
819 mstb
->tx_slots
[0] = NULL
;
822 if (mstb
->tx_slots
[1]) {
823 mstb
->tx_slots
[1]->state
= DRM_DP_SIDEBAND_TX_TIMEOUT
;
824 mstb
->tx_slots
[1] = NULL
;
827 mutex_unlock(&mstb
->mgr
->qlock
);
830 wake_up(&mstb
->mgr
->tx_waitq
);
834 static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch
*mstb
)
836 kref_put(&mstb
->kref
, drm_dp_destroy_mst_branch_device
);
840 static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port
*port
, int old_pdt
)
842 struct drm_dp_mst_branch
*mstb
;
845 case DP_PEER_DEVICE_DP_LEGACY_CONV
:
846 case DP_PEER_DEVICE_SST_SINK
:
847 /* remove i2c over sideband */
848 drm_dp_mst_unregister_i2c_bus(&port
->aux
);
850 case DP_PEER_DEVICE_MST_BRANCHING
:
853 drm_dp_put_mst_branch_device(mstb
);
858 static void drm_dp_destroy_port(struct kref
*kref
)
860 struct drm_dp_mst_port
*port
= container_of(kref
, struct drm_dp_mst_port
, kref
);
861 struct drm_dp_mst_topology_mgr
*mgr
= port
->mgr
;
863 port
->vcpi
.num_slots
= 0;
865 kfree(port
->cached_edid
);
867 (*port
->mgr
->cbs
->destroy_connector
)(mgr
, port
->connector
);
868 drm_dp_port_teardown_pdt(port
, port
->pdt
);
870 if (!port
->input
&& port
->vcpi
.vcpi
> 0)
871 drm_dp_mst_put_payload_id(mgr
, port
->vcpi
.vcpi
);
875 (*mgr
->cbs
->hotplug
)(mgr
);
878 static void drm_dp_put_port(struct drm_dp_mst_port
*port
)
880 kref_put(&port
->kref
, drm_dp_destroy_port
);
883 static struct drm_dp_mst_branch
*drm_dp_mst_get_validated_mstb_ref_locked(struct drm_dp_mst_branch
*mstb
, struct drm_dp_mst_branch
*to_find
)
885 struct drm_dp_mst_port
*port
;
886 struct drm_dp_mst_branch
*rmstb
;
887 if (to_find
== mstb
) {
888 kref_get(&mstb
->kref
);
891 list_for_each_entry(port
, &mstb
->ports
, next
) {
893 rmstb
= drm_dp_mst_get_validated_mstb_ref_locked(port
->mstb
, to_find
);
901 static struct drm_dp_mst_branch
*drm_dp_get_validated_mstb_ref(struct drm_dp_mst_topology_mgr
*mgr
, struct drm_dp_mst_branch
*mstb
)
903 struct drm_dp_mst_branch
*rmstb
= NULL
;
904 mutex_lock(&mgr
->lock
);
905 if (mgr
->mst_primary
)
906 rmstb
= drm_dp_mst_get_validated_mstb_ref_locked(mgr
->mst_primary
, mstb
);
907 mutex_unlock(&mgr
->lock
);
911 static struct drm_dp_mst_port
*drm_dp_mst_get_port_ref_locked(struct drm_dp_mst_branch
*mstb
, struct drm_dp_mst_port
*to_find
)
913 struct drm_dp_mst_port
*port
, *mport
;
915 list_for_each_entry(port
, &mstb
->ports
, next
) {
916 if (port
== to_find
) {
917 kref_get(&port
->kref
);
921 mport
= drm_dp_mst_get_port_ref_locked(port
->mstb
, to_find
);
929 static struct drm_dp_mst_port
*drm_dp_get_validated_port_ref(struct drm_dp_mst_topology_mgr
*mgr
, struct drm_dp_mst_port
*port
)
931 struct drm_dp_mst_port
*rport
= NULL
;
932 mutex_lock(&mgr
->lock
);
933 if (mgr
->mst_primary
)
934 rport
= drm_dp_mst_get_port_ref_locked(mgr
->mst_primary
, port
);
935 mutex_unlock(&mgr
->lock
);
939 static struct drm_dp_mst_port
*drm_dp_get_port(struct drm_dp_mst_branch
*mstb
, u8 port_num
)
941 struct drm_dp_mst_port
*port
;
943 list_for_each_entry(port
, &mstb
->ports
, next
) {
944 if (port
->port_num
== port_num
) {
945 kref_get(&port
->kref
);
954 * calculate a new RAD for this MST branch device
955 * if parent has an LCT of 2 then it has 1 nibble of RAD,
956 * if parent has an LCT of 3 then it has 2 nibbles of RAD,
958 static u8
drm_dp_calculate_rad(struct drm_dp_mst_port
*port
,
961 int lct
= port
->parent
->lct
;
965 memcpy(rad
, port
->parent
->rad
, idx
);
966 shift
= (lct
% 2) ? 4 : 0;
970 rad
[idx
] |= port
->port_num
<< shift
;
975 * return sends link address for new mstb
977 static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port
*port
)
981 bool send_link
= false;
983 case DP_PEER_DEVICE_DP_LEGACY_CONV
:
984 case DP_PEER_DEVICE_SST_SINK
:
985 /* add i2c over sideband */
986 ret
= drm_dp_mst_register_i2c_bus(&port
->aux
);
988 case DP_PEER_DEVICE_MST_BRANCHING
:
989 lct
= drm_dp_calculate_rad(port
, rad
);
991 port
->mstb
= drm_dp_add_mst_branch_device(lct
, rad
);
992 port
->mstb
->mgr
= port
->mgr
;
993 port
->mstb
->port_parent
= port
;
1001 static void drm_dp_check_port_guid(struct drm_dp_mst_branch
*mstb
,
1002 struct drm_dp_mst_port
*port
)
1005 if (port
->dpcd_rev
>= 0x12) {
1006 port
->guid_valid
= drm_dp_validate_guid(mstb
->mgr
, port
->guid
);
1007 if (!port
->guid_valid
) {
1008 ret
= drm_dp_send_dpcd_write(mstb
->mgr
,
1012 port
->guid_valid
= true;
1017 static void build_mst_prop_path(struct drm_dp_mst_port
*port
,
1018 struct drm_dp_mst_branch
*mstb
,
1020 size_t proppath_size
)
1024 snprintf(proppath
, proppath_size
, "mst:%d", mstb
->mgr
->conn_base_id
);
1025 for (i
= 0; i
< (mstb
->lct
- 1); i
++) {
1026 int shift
= (i
% 2) ? 0 : 4;
1027 int port_num
= mstb
->rad
[i
/ 2] >> shift
;
1028 snprintf(temp
, sizeof(temp
), "-%d", port_num
);
1029 strlcat(proppath
, temp
, proppath_size
);
1031 snprintf(temp
, sizeof(temp
), "-%d", port
->port_num
);
1032 strlcat(proppath
, temp
, proppath_size
);
1035 static void drm_dp_add_port(struct drm_dp_mst_branch
*mstb
,
1037 struct drm_dp_link_addr_reply_port
*port_msg
)
1039 struct drm_dp_mst_port
*port
;
1041 bool created
= false;
1044 port
= drm_dp_get_port(mstb
, port_msg
->port_number
);
1046 port
= kzalloc(sizeof(*port
), GFP_KERNEL
);
1049 kref_init(&port
->kref
);
1050 port
->parent
= mstb
;
1051 port
->port_num
= port_msg
->port_number
;
1052 port
->mgr
= mstb
->mgr
;
1053 port
->aux
.name
= "DPMST";
1054 port
->aux
.dev
= dev
;
1057 old_pdt
= port
->pdt
;
1058 old_ddps
= port
->ddps
;
1061 port
->pdt
= port_msg
->peer_device_type
;
1062 port
->input
= port_msg
->input_port
;
1063 port
->mcs
= port_msg
->mcs
;
1064 port
->ddps
= port_msg
->ddps
;
1065 port
->ldps
= port_msg
->legacy_device_plug_status
;
1066 port
->dpcd_rev
= port_msg
->dpcd_revision
;
1067 port
->num_sdp_streams
= port_msg
->num_sdp_streams
;
1068 port
->num_sdp_stream_sinks
= port_msg
->num_sdp_stream_sinks
;
1069 memcpy(port
->guid
, port_msg
->peer_guid
, 16);
1071 /* manage mstb port lists with mgr lock - take a reference
1074 mutex_lock(&mstb
->mgr
->lock
);
1075 kref_get(&port
->kref
);
1076 list_add(&port
->next
, &mstb
->ports
);
1077 mutex_unlock(&mstb
->mgr
->lock
);
1080 if (old_ddps
!= port
->ddps
) {
1082 drm_dp_check_port_guid(mstb
, port
);
1084 drm_dp_send_enum_path_resources(mstb
->mgr
, mstb
, port
);
1086 port
->guid_valid
= false;
1087 port
->available_pbn
= 0;
1091 if (old_pdt
!= port
->pdt
&& !port
->input
) {
1092 drm_dp_port_teardown_pdt(port
, old_pdt
);
1094 ret
= drm_dp_port_setup_pdt(port
);
1096 drm_dp_send_link_address(mstb
->mgr
, port
->mstb
);
1097 port
->mstb
->link_address_sent
= true;
1101 if (created
&& !port
->input
) {
1103 build_mst_prop_path(port
, mstb
, proppath
, sizeof(proppath
));
1104 port
->connector
= (*mstb
->mgr
->cbs
->add_connector
)(mstb
->mgr
, port
, proppath
);
1106 if (port
->port_num
>= 8) {
1107 port
->cached_edid
= drm_get_edid(port
->connector
, &port
->aux
.ddc
);
1111 /* put reference to this port */
1112 drm_dp_put_port(port
);
1115 static void drm_dp_update_port(struct drm_dp_mst_branch
*mstb
,
1116 struct drm_dp_connection_status_notify
*conn_stat
)
1118 struct drm_dp_mst_port
*port
;
1121 bool dowork
= false;
1122 port
= drm_dp_get_port(mstb
, conn_stat
->port_number
);
1126 old_ddps
= port
->ddps
;
1127 old_pdt
= port
->pdt
;
1128 port
->pdt
= conn_stat
->peer_device_type
;
1129 port
->mcs
= conn_stat
->message_capability_status
;
1130 port
->ldps
= conn_stat
->legacy_device_plug_status
;
1131 port
->ddps
= conn_stat
->displayport_device_plug_status
;
1133 if (old_ddps
!= port
->ddps
) {
1135 drm_dp_check_port_guid(mstb
, port
);
1138 port
->guid_valid
= false;
1139 port
->available_pbn
= 0;
1142 if (old_pdt
!= port
->pdt
&& !port
->input
) {
1143 drm_dp_port_teardown_pdt(port
, old_pdt
);
1145 if (drm_dp_port_setup_pdt(port
))
1149 drm_dp_put_port(port
);
1151 queue_work(system_long_wq
, &mstb
->mgr
->work
);
1155 static struct drm_dp_mst_branch
*drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr
*mgr
,
1158 struct drm_dp_mst_branch
*mstb
;
1159 struct drm_dp_mst_port
*port
;
1161 /* find the port by iterating down */
1162 mstb
= mgr
->mst_primary
;
1164 for (i
= 0; i
< lct
- 1; i
++) {
1165 int shift
= (i
% 2) ? 0 : 4;
1166 int port_num
= rad
[i
/ 2] >> shift
;
1168 list_for_each_entry(port
, &mstb
->ports
, next
) {
1169 if (port
->port_num
== port_num
) {
1171 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct
, rad
[0]);
1180 kref_get(&mstb
->kref
);
1184 static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr
*mgr
,
1185 struct drm_dp_mst_branch
*mstb
)
1187 struct drm_dp_mst_port
*port
;
1189 if (!mstb
->link_address_sent
) {
1190 drm_dp_send_link_address(mgr
, mstb
);
1191 mstb
->link_address_sent
= true;
1193 list_for_each_entry(port
, &mstb
->ports
, next
) {
1200 if (!port
->available_pbn
)
1201 drm_dp_send_enum_path_resources(mgr
, mstb
, port
);
1204 drm_dp_check_and_send_link_address(mgr
, port
->mstb
);
1208 static void drm_dp_mst_link_probe_work(struct work_struct
*work
)
1210 struct drm_dp_mst_topology_mgr
*mgr
= container_of(work
, struct drm_dp_mst_topology_mgr
, work
);
1212 drm_dp_check_and_send_link_address(mgr
, mgr
->mst_primary
);
1216 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr
*mgr
,
1219 static u8 zero_guid
[16];
1221 if (!memcmp(guid
, zero_guid
, 16)) {
1222 u64 salt
= get_jiffies_64();
1223 memcpy(&guid
[0], &salt
, sizeof(u64
));
1224 memcpy(&guid
[8], &salt
, sizeof(u64
));
1231 static int build_dpcd_read(struct drm_dp_sideband_msg_tx
*msg
, u8 port_num
, u32 offset
, u8 num_bytes
)
1233 struct drm_dp_sideband_msg_req_body req
;
1235 req
.req_type
= DP_REMOTE_DPCD_READ
;
1236 req
.u
.dpcd_read
.port_number
= port_num
;
1237 req
.u
.dpcd_read
.dpcd_address
= offset
;
1238 req
.u
.dpcd_read
.num_bytes
= num_bytes
;
1239 drm_dp_encode_sideband_req(&req
, msg
);
1245 static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr
*mgr
,
1246 bool up
, u8
*msg
, int len
)
1249 int regbase
= up
? DP_SIDEBAND_MSG_UP_REP_BASE
: DP_SIDEBAND_MSG_DOWN_REQ_BASE
;
1250 int tosend
, total
, offset
;
1257 tosend
= min3(mgr
->max_dpcd_transaction_bytes
, 16, total
);
1259 ret
= drm_dp_dpcd_write(mgr
->aux
, regbase
+ offset
,
1262 if (ret
!= tosend
) {
1263 if (ret
== -EIO
&& retries
< 5) {
1267 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend
, ret
);
1274 } while (total
> 0);
1278 static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr
*hdr
,
1279 struct drm_dp_sideband_msg_tx
*txmsg
)
1281 struct drm_dp_mst_branch
*mstb
= txmsg
->dst
;
1283 /* both msg slots are full */
1284 if (txmsg
->seqno
== -1) {
1285 if (mstb
->tx_slots
[0] && mstb
->tx_slots
[1]) {
1286 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__
);
1289 if (mstb
->tx_slots
[0] == NULL
&& mstb
->tx_slots
[1] == NULL
) {
1290 txmsg
->seqno
= mstb
->last_seqno
;
1291 mstb
->last_seqno
^= 1;
1292 } else if (mstb
->tx_slots
[0] == NULL
)
1296 mstb
->tx_slots
[txmsg
->seqno
] = txmsg
;
1299 hdr
->path_msg
= txmsg
->path_msg
;
1300 hdr
->lct
= mstb
->lct
;
1301 hdr
->lcr
= mstb
->lct
- 1;
1303 memcpy(hdr
->rad
, mstb
->rad
, mstb
->lct
/ 2);
1304 hdr
->seqno
= txmsg
->seqno
;
1308 * process a single block of the next message in the sideband queue
1310 static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr
*mgr
,
1311 struct drm_dp_sideband_msg_tx
*txmsg
,
1315 struct drm_dp_sideband_msg_hdr hdr
;
1316 int len
, space
, idx
, tosend
;
1319 memset(&hdr
, 0, sizeof(struct drm_dp_sideband_msg_hdr
));
1321 if (txmsg
->state
== DRM_DP_SIDEBAND_TX_QUEUED
) {
1323 txmsg
->state
= DRM_DP_SIDEBAND_TX_START_SEND
;
1326 /* make hdr from dst mst - for replies use seqno
1327 otherwise assign one */
1328 ret
= set_hdr_from_dst_qlock(&hdr
, txmsg
);
1332 /* amount left to send in this message */
1333 len
= txmsg
->cur_len
- txmsg
->cur_offset
;
1335 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
1336 space
= 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr
);
1338 tosend
= min(len
, space
);
1339 if (len
== txmsg
->cur_len
)
1345 hdr
.msg_len
= tosend
+ 1;
1346 drm_dp_encode_sideband_msg_hdr(&hdr
, chunk
, &idx
);
1347 memcpy(&chunk
[idx
], &txmsg
->msg
[txmsg
->cur_offset
], tosend
);
1348 /* add crc at end */
1349 drm_dp_crc_sideband_chunk_req(&chunk
[idx
], tosend
);
1352 ret
= drm_dp_send_sideband_msg(mgr
, up
, chunk
, idx
);
1354 DRM_DEBUG_KMS("sideband msg failed to send\n");
1358 txmsg
->cur_offset
+= tosend
;
1359 if (txmsg
->cur_offset
== txmsg
->cur_len
) {
1360 txmsg
->state
= DRM_DP_SIDEBAND_TX_SENT
;
1366 /* must be called holding qlock */
1367 static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr
*mgr
)
1369 struct drm_dp_sideband_msg_tx
*txmsg
;
1372 /* construct a chunk from the first msg in the tx_msg queue */
1373 if (list_empty(&mgr
->tx_msg_downq
)) {
1374 mgr
->tx_down_in_progress
= false;
1377 mgr
->tx_down_in_progress
= true;
1379 txmsg
= list_first_entry(&mgr
->tx_msg_downq
, struct drm_dp_sideband_msg_tx
, next
);
1380 ret
= process_single_tx_qlock(mgr
, txmsg
, false);
1382 /* txmsg is sent it should be in the slots now */
1383 list_del(&txmsg
->next
);
1385 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret
);
1386 list_del(&txmsg
->next
);
1387 if (txmsg
->seqno
!= -1)
1388 txmsg
->dst
->tx_slots
[txmsg
->seqno
] = NULL
;
1389 txmsg
->state
= DRM_DP_SIDEBAND_TX_TIMEOUT
;
1390 wake_up(&mgr
->tx_waitq
);
1392 if (list_empty(&mgr
->tx_msg_downq
)) {
1393 mgr
->tx_down_in_progress
= false;
1398 /* called holding qlock */
1399 static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr
*mgr
)
1401 struct drm_dp_sideband_msg_tx
*txmsg
;
1404 /* construct a chunk from the first msg in the tx_msg queue */
1405 if (list_empty(&mgr
->tx_msg_upq
)) {
1406 mgr
->tx_up_in_progress
= false;
1410 txmsg
= list_first_entry(&mgr
->tx_msg_upq
, struct drm_dp_sideband_msg_tx
, next
);
1411 ret
= process_single_tx_qlock(mgr
, txmsg
, true);
1413 /* up txmsgs aren't put in slots - so free after we send it */
1414 list_del(&txmsg
->next
);
1417 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret
);
1418 mgr
->tx_up_in_progress
= true;
1421 static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr
*mgr
,
1422 struct drm_dp_sideband_msg_tx
*txmsg
)
1424 mutex_lock(&mgr
->qlock
);
1425 list_add_tail(&txmsg
->next
, &mgr
->tx_msg_downq
);
1426 if (!mgr
->tx_down_in_progress
)
1427 process_single_down_tx_qlock(mgr
);
1428 mutex_unlock(&mgr
->qlock
);
1431 static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr
*mgr
,
1432 struct drm_dp_mst_branch
*mstb
)
1435 struct drm_dp_sideband_msg_tx
*txmsg
;
1438 txmsg
= kzalloc(sizeof(*txmsg
), GFP_KERNEL
);
1443 len
= build_link_address(txmsg
);
1445 drm_dp_queue_down_tx(mgr
, txmsg
);
1447 ret
= drm_dp_mst_wait_tx_reply(mstb
, txmsg
);
1451 if (txmsg
->reply
.reply_type
== 1)
1452 DRM_DEBUG_KMS("link address nak received\n");
1454 DRM_DEBUG_KMS("link address reply: %d\n", txmsg
->reply
.u
.link_addr
.nports
);
1455 for (i
= 0; i
< txmsg
->reply
.u
.link_addr
.nports
; i
++) {
1456 DRM_DEBUG_KMS("port %d: input %d, pdt: %d, pn: %d, dpcd_rev: %02x, mcs: %d, ddps: %d, ldps %d, sdp %d/%d\n", i
,
1457 txmsg
->reply
.u
.link_addr
.ports
[i
].input_port
,
1458 txmsg
->reply
.u
.link_addr
.ports
[i
].peer_device_type
,
1459 txmsg
->reply
.u
.link_addr
.ports
[i
].port_number
,
1460 txmsg
->reply
.u
.link_addr
.ports
[i
].dpcd_revision
,
1461 txmsg
->reply
.u
.link_addr
.ports
[i
].mcs
,
1462 txmsg
->reply
.u
.link_addr
.ports
[i
].ddps
,
1463 txmsg
->reply
.u
.link_addr
.ports
[i
].legacy_device_plug_status
,
1464 txmsg
->reply
.u
.link_addr
.ports
[i
].num_sdp_streams
,
1465 txmsg
->reply
.u
.link_addr
.ports
[i
].num_sdp_stream_sinks
);
1467 for (i
= 0; i
< txmsg
->reply
.u
.link_addr
.nports
; i
++) {
1468 drm_dp_add_port(mstb
, mgr
->dev
, &txmsg
->reply
.u
.link_addr
.ports
[i
]);
1470 (*mgr
->cbs
->hotplug
)(mgr
);
1473 DRM_DEBUG_KMS("link address failed %d\n", ret
);
1479 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr
*mgr
,
1480 struct drm_dp_mst_branch
*mstb
,
1481 struct drm_dp_mst_port
*port
)
1484 struct drm_dp_sideband_msg_tx
*txmsg
;
1487 txmsg
= kzalloc(sizeof(*txmsg
), GFP_KERNEL
);
1492 len
= build_enum_path_resources(txmsg
, port
->port_num
);
1494 drm_dp_queue_down_tx(mgr
, txmsg
);
1496 ret
= drm_dp_mst_wait_tx_reply(mstb
, txmsg
);
1498 if (txmsg
->reply
.reply_type
== 1)
1499 DRM_DEBUG_KMS("enum path resources nak received\n");
1501 if (port
->port_num
!= txmsg
->reply
.u
.path_resources
.port_number
)
1502 DRM_ERROR("got incorrect port in response\n");
1503 DRM_DEBUG_KMS("enum path resources %d: %d %d\n", txmsg
->reply
.u
.path_resources
.port_number
, txmsg
->reply
.u
.path_resources
.full_payload_bw_number
,
1504 txmsg
->reply
.u
.path_resources
.avail_payload_bw_number
);
1505 port
->available_pbn
= txmsg
->reply
.u
.path_resources
.avail_payload_bw_number
;
1513 static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr
*mgr
,
1514 struct drm_dp_mst_port
*port
,
1518 struct drm_dp_sideband_msg_tx
*txmsg
;
1519 struct drm_dp_mst_branch
*mstb
;
1522 mstb
= drm_dp_get_validated_mstb_ref(mgr
, port
->parent
);
1526 txmsg
= kzalloc(sizeof(*txmsg
), GFP_KERNEL
);
1533 len
= build_allocate_payload(txmsg
, port
->port_num
,
1537 drm_dp_queue_down_tx(mgr
, txmsg
);
1539 ret
= drm_dp_mst_wait_tx_reply(mstb
, txmsg
);
1541 if (txmsg
->reply
.reply_type
== 1) {
1548 drm_dp_put_mst_branch_device(mstb
);
1552 static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr
*mgr
,
1554 struct drm_dp_payload
*payload
)
1558 ret
= drm_dp_dpcd_write_payload(mgr
, id
, payload
);
1560 payload
->payload_state
= 0;
1563 payload
->payload_state
= DP_PAYLOAD_LOCAL
;
1567 static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr
*mgr
,
1568 struct drm_dp_mst_port
*port
,
1570 struct drm_dp_payload
*payload
)
1573 ret
= drm_dp_payload_send_msg(mgr
, port
, id
, port
->vcpi
.pbn
);
1576 payload
->payload_state
= DP_PAYLOAD_REMOTE
;
1580 static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr
*mgr
,
1581 struct drm_dp_mst_port
*port
,
1583 struct drm_dp_payload
*payload
)
1585 DRM_DEBUG_KMS("\n");
1586 /* its okay for these to fail */
1588 drm_dp_payload_send_msg(mgr
, port
, id
, 0);
1591 drm_dp_dpcd_write_payload(mgr
, id
, payload
);
1592 payload
->payload_state
= DP_PAYLOAD_DELETE_LOCAL
;
1596 static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr
*mgr
,
1598 struct drm_dp_payload
*payload
)
1600 payload
->payload_state
= 0;
1605 * drm_dp_update_payload_part1() - Execute payload update part 1
1606 * @mgr: manager to use.
1608 * This iterates over all proposed virtual channels, and tries to
1609 * allocate space in the link for them. For 0->slots transitions,
1610 * this step just writes the VCPI to the MST device. For slots->0
1611 * transitions, this writes the updated VCPIs and removes the
1612 * remote VC payloads.
1614 * after calling this the driver should generate ACT and payload
1617 int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr
*mgr
)
1621 struct drm_dp_payload req_payload
;
1622 struct drm_dp_mst_port
*port
;
1624 mutex_lock(&mgr
->payload_lock
);
1625 for (i
= 0; i
< mgr
->max_payloads
; i
++) {
1626 /* solve the current payloads - compare to the hw ones
1627 - update the hw view */
1628 req_payload
.start_slot
= cur_slots
;
1629 if (mgr
->proposed_vcpis
[i
]) {
1630 port
= container_of(mgr
->proposed_vcpis
[i
], struct drm_dp_mst_port
, vcpi
);
1631 req_payload
.num_slots
= mgr
->proposed_vcpis
[i
]->num_slots
;
1634 req_payload
.num_slots
= 0;
1637 if (mgr
->payloads
[i
].start_slot
!= req_payload
.start_slot
) {
1638 mgr
->payloads
[i
].start_slot
= req_payload
.start_slot
;
1640 /* work out what is required to happen with this payload */
1641 if (mgr
->payloads
[i
].num_slots
!= req_payload
.num_slots
) {
1643 /* need to push an update for this payload */
1644 if (req_payload
.num_slots
) {
1645 drm_dp_create_payload_step1(mgr
, mgr
->proposed_vcpis
[i
]->vcpi
, &req_payload
);
1646 mgr
->payloads
[i
].num_slots
= req_payload
.num_slots
;
1647 } else if (mgr
->payloads
[i
].num_slots
) {
1648 mgr
->payloads
[i
].num_slots
= 0;
1649 drm_dp_destroy_payload_step1(mgr
, port
, port
->vcpi
.vcpi
, &mgr
->payloads
[i
]);
1650 req_payload
.payload_state
= mgr
->payloads
[i
].payload_state
;
1651 mgr
->payloads
[i
].start_slot
= 0;
1653 mgr
->payloads
[i
].payload_state
= req_payload
.payload_state
;
1655 cur_slots
+= req_payload
.num_slots
;
1658 for (i
= 0; i
< mgr
->max_payloads
; i
++) {
1659 if (mgr
->payloads
[i
].payload_state
== DP_PAYLOAD_DELETE_LOCAL
) {
1660 DRM_DEBUG_KMS("removing payload %d\n", i
);
1661 for (j
= i
; j
< mgr
->max_payloads
- 1; j
++) {
1662 memcpy(&mgr
->payloads
[j
], &mgr
->payloads
[j
+ 1], sizeof(struct drm_dp_payload
));
1663 mgr
->proposed_vcpis
[j
] = mgr
->proposed_vcpis
[j
+ 1];
1664 if (mgr
->proposed_vcpis
[j
] && mgr
->proposed_vcpis
[j
]->num_slots
) {
1665 set_bit(j
+ 1, &mgr
->payload_mask
);
1667 clear_bit(j
+ 1, &mgr
->payload_mask
);
1670 memset(&mgr
->payloads
[mgr
->max_payloads
- 1], 0, sizeof(struct drm_dp_payload
));
1671 mgr
->proposed_vcpis
[mgr
->max_payloads
- 1] = NULL
;
1672 clear_bit(mgr
->max_payloads
, &mgr
->payload_mask
);
1676 mutex_unlock(&mgr
->payload_lock
);
1680 EXPORT_SYMBOL(drm_dp_update_payload_part1
);
1683 * drm_dp_update_payload_part2() - Execute payload update part 2
1684 * @mgr: manager to use.
1686 * This iterates over all proposed virtual channels, and tries to
1687 * allocate space in the link for them. For 0->slots transitions,
1688 * this step writes the remote VC payload commands. For slots->0
1689 * this just resets some internal state.
1691 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr
*mgr
)
1693 struct drm_dp_mst_port
*port
;
1696 mutex_lock(&mgr
->payload_lock
);
1697 for (i
= 0; i
< mgr
->max_payloads
; i
++) {
1699 if (!mgr
->proposed_vcpis
[i
])
1702 port
= container_of(mgr
->proposed_vcpis
[i
], struct drm_dp_mst_port
, vcpi
);
1704 DRM_DEBUG_KMS("payload %d %d\n", i
, mgr
->payloads
[i
].payload_state
);
1705 if (mgr
->payloads
[i
].payload_state
== DP_PAYLOAD_LOCAL
) {
1706 ret
= drm_dp_create_payload_step2(mgr
, port
, mgr
->proposed_vcpis
[i
]->vcpi
, &mgr
->payloads
[i
]);
1707 } else if (mgr
->payloads
[i
].payload_state
== DP_PAYLOAD_DELETE_LOCAL
) {
1708 ret
= drm_dp_destroy_payload_step2(mgr
, mgr
->proposed_vcpis
[i
]->vcpi
, &mgr
->payloads
[i
]);
1711 mutex_unlock(&mgr
->payload_lock
);
1715 mutex_unlock(&mgr
->payload_lock
);
1718 EXPORT_SYMBOL(drm_dp_update_payload_part2
);
1720 #if 0 /* unused as of yet */
1721 static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr
*mgr
,
1722 struct drm_dp_mst_port
*port
,
1723 int offset
, int size
)
1726 struct drm_dp_sideband_msg_tx
*txmsg
;
1728 txmsg
= kzalloc(sizeof(*txmsg
), GFP_KERNEL
);
1732 len
= build_dpcd_read(txmsg
, port
->port_num
, 0, 8);
1733 txmsg
->dst
= port
->parent
;
1735 drm_dp_queue_down_tx(mgr
, txmsg
);
1741 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr
*mgr
,
1742 struct drm_dp_mst_port
*port
,
1743 int offset
, int size
, u8
*bytes
)
1747 struct drm_dp_sideband_msg_tx
*txmsg
;
1748 struct drm_dp_mst_branch
*mstb
;
1750 mstb
= drm_dp_get_validated_mstb_ref(mgr
, port
->parent
);
1754 txmsg
= kzalloc(sizeof(*txmsg
), GFP_KERNEL
);
1760 len
= build_dpcd_write(txmsg
, port
->port_num
, offset
, size
, bytes
);
1763 drm_dp_queue_down_tx(mgr
, txmsg
);
1765 ret
= drm_dp_mst_wait_tx_reply(mstb
, txmsg
);
1767 if (txmsg
->reply
.reply_type
== 1) {
1774 drm_dp_put_mst_branch_device(mstb
);
1778 static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx
*msg
, u8 req_type
)
1780 struct drm_dp_sideband_msg_reply_body reply
;
1782 reply
.reply_type
= 1;
1783 reply
.req_type
= req_type
;
1784 drm_dp_encode_sideband_reply(&reply
, msg
);
1788 static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr
*mgr
,
1789 struct drm_dp_mst_branch
*mstb
,
1790 int req_type
, int seqno
, bool broadcast
)
1792 struct drm_dp_sideband_msg_tx
*txmsg
;
1794 txmsg
= kzalloc(sizeof(*txmsg
), GFP_KERNEL
);
1799 txmsg
->seqno
= seqno
;
1800 drm_dp_encode_up_ack_reply(txmsg
, req_type
);
1802 mutex_lock(&mgr
->qlock
);
1803 list_add_tail(&txmsg
->next
, &mgr
->tx_msg_upq
);
1804 if (!mgr
->tx_up_in_progress
) {
1805 process_single_up_tx_qlock(mgr
);
1807 mutex_unlock(&mgr
->qlock
);
1811 static bool drm_dp_get_vc_payload_bw(int dp_link_bw
,
1815 switch (dp_link_bw
) {
1817 DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n",
1818 dp_link_bw
, dp_link_count
);
1821 case DP_LINK_BW_1_62
:
1822 *out
= 3 * dp_link_count
;
1824 case DP_LINK_BW_2_7
:
1825 *out
= 5 * dp_link_count
;
1827 case DP_LINK_BW_5_4
:
1828 *out
= 10 * dp_link_count
;
1835 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
1836 * @mgr: manager to set state for
1837 * @mst_state: true to enable MST on this connector - false to disable.
1839 * This is called by the driver when it detects an MST capable device plugged
1840 * into a DP MST capable port, or when a DP MST capable device is unplugged.
1842 int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr
*mgr
, bool mst_state
)
1845 struct drm_dp_mst_branch
*mstb
= NULL
;
1847 mutex_lock(&mgr
->lock
);
1848 if (mst_state
== mgr
->mst_state
)
1851 mgr
->mst_state
= mst_state
;
1852 /* set the device into MST mode */
1854 WARN_ON(mgr
->mst_primary
);
1857 ret
= drm_dp_dpcd_read(mgr
->aux
, DP_DPCD_REV
, mgr
->dpcd
, DP_RECEIVER_CAP_SIZE
);
1858 if (ret
!= DP_RECEIVER_CAP_SIZE
) {
1859 DRM_DEBUG_KMS("failed to read DPCD\n");
1863 if (!drm_dp_get_vc_payload_bw(mgr
->dpcd
[1],
1864 mgr
->dpcd
[2] & DP_MAX_LANE_COUNT_MASK
,
1870 mgr
->total_pbn
= 2560;
1871 mgr
->total_slots
= DIV_ROUND_UP(mgr
->total_pbn
, mgr
->pbn_div
);
1872 mgr
->avail_slots
= mgr
->total_slots
;
1874 /* add initial branch device at LCT 1 */
1875 mstb
= drm_dp_add_mst_branch_device(1, NULL
);
1882 /* give this the main reference */
1883 mgr
->mst_primary
= mstb
;
1884 kref_get(&mgr
->mst_primary
->kref
);
1887 struct drm_dp_payload reset_pay
;
1888 reset_pay
.start_slot
= 0;
1889 reset_pay
.num_slots
= 0x3f;
1890 drm_dp_dpcd_write_payload(mgr
, 0, &reset_pay
);
1893 ret
= drm_dp_dpcd_writeb(mgr
->aux
, DP_MSTM_CTRL
,
1894 DP_MST_EN
| DP_UP_REQ_EN
| DP_UPSTREAM_IS_SRC
);
1901 ret
= drm_dp_dpcd_read(mgr
->aux
, DP_GUID
, mgr
->guid
, 16);
1903 DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret
);
1907 mgr
->guid_valid
= drm_dp_validate_guid(mgr
, mgr
->guid
);
1908 if (!mgr
->guid_valid
) {
1909 ret
= drm_dp_dpcd_write(mgr
->aux
, DP_GUID
, mgr
->guid
, 16);
1910 mgr
->guid_valid
= true;
1913 queue_work(system_long_wq
, &mgr
->work
);
1917 /* disable MST on the device */
1918 mstb
= mgr
->mst_primary
;
1919 mgr
->mst_primary
= NULL
;
1920 /* this can fail if the device is gone */
1921 drm_dp_dpcd_writeb(mgr
->aux
, DP_MSTM_CTRL
, 0);
1923 memset(mgr
->payloads
, 0, mgr
->max_payloads
* sizeof(struct drm_dp_payload
));
1924 mgr
->payload_mask
= 0;
1925 set_bit(0, &mgr
->payload_mask
);
1930 mutex_unlock(&mgr
->lock
);
1932 drm_dp_put_mst_branch_device(mstb
);
1936 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst
);
1939 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
1940 * @mgr: manager to suspend
1942 * This function tells the MST device that we can't handle UP messages
1943 * anymore. This should stop it from sending any since we are suspended.
1945 void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr
*mgr
)
1947 mutex_lock(&mgr
->lock
);
1948 drm_dp_dpcd_writeb(mgr
->aux
, DP_MSTM_CTRL
,
1949 DP_MST_EN
| DP_UPSTREAM_IS_SRC
);
1950 mutex_unlock(&mgr
->lock
);
1952 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend
);
1955 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
1956 * @mgr: manager to resume
1958 * This will fetch DPCD and see if the device is still there,
1959 * if it is, it will rewrite the MSTM control bits, and return.
1961 * if the device fails this returns -1, and the driver should do
1962 * a full MST reprobe, in case we were undocked.
1964 int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr
*mgr
)
1968 mutex_lock(&mgr
->lock
);
1970 if (mgr
->mst_primary
) {
1972 sret
= drm_dp_dpcd_read(mgr
->aux
, DP_DPCD_REV
, mgr
->dpcd
, DP_RECEIVER_CAP_SIZE
);
1973 if (sret
!= DP_RECEIVER_CAP_SIZE
) {
1974 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
1979 ret
= drm_dp_dpcd_writeb(mgr
->aux
, DP_MSTM_CTRL
,
1980 DP_MST_EN
| DP_UP_REQ_EN
| DP_UPSTREAM_IS_SRC
);
1982 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
1991 mutex_unlock(&mgr
->lock
);
1994 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume
);
1996 static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr
*mgr
, bool up
)
2000 int replylen
, origlen
, curreply
;
2002 struct drm_dp_sideband_msg_rx
*msg
;
2003 int basereg
= up
? DP_SIDEBAND_MSG_UP_REQ_BASE
: DP_SIDEBAND_MSG_DOWN_REP_BASE
;
2004 msg
= up
? &mgr
->up_req_recv
: &mgr
->down_rep_recv
;
2006 len
= min(mgr
->max_dpcd_transaction_bytes
, 16);
2007 ret
= drm_dp_dpcd_read(mgr
->aux
, basereg
,
2010 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len
, ret
);
2013 ret
= drm_dp_sideband_msg_build(msg
, replyblock
, len
, true);
2015 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock
[0]);
2018 replylen
= msg
->curchunk_len
+ msg
->curchunk_hdrlen
;
2023 while (replylen
> 0) {
2024 len
= min3(replylen
, mgr
->max_dpcd_transaction_bytes
, 16);
2025 ret
= drm_dp_dpcd_read(mgr
->aux
, basereg
+ curreply
,
2028 DRM_DEBUG_KMS("failed to read a chunk\n");
2030 ret
= drm_dp_sideband_msg_build(msg
, replyblock
, len
, false);
2032 DRM_DEBUG_KMS("failed to build sideband msg\n");
2038 static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr
*mgr
)
2042 drm_dp_get_one_sb_msg(mgr
, false);
2044 if (mgr
->down_rep_recv
.have_eomt
) {
2045 struct drm_dp_sideband_msg_tx
*txmsg
;
2046 struct drm_dp_mst_branch
*mstb
;
2048 mstb
= drm_dp_get_mst_branch_device(mgr
,
2049 mgr
->down_rep_recv
.initial_hdr
.lct
,
2050 mgr
->down_rep_recv
.initial_hdr
.rad
);
2053 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr
->down_rep_recv
.initial_hdr
.lct
);
2054 memset(&mgr
->down_rep_recv
, 0, sizeof(struct drm_dp_sideband_msg_rx
));
2058 /* find the message */
2059 slot
= mgr
->down_rep_recv
.initial_hdr
.seqno
;
2060 mutex_lock(&mgr
->qlock
);
2061 txmsg
= mstb
->tx_slots
[slot
];
2062 /* remove from slots */
2063 mutex_unlock(&mgr
->qlock
);
2066 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
2068 mgr
->down_rep_recv
.initial_hdr
.seqno
,
2069 mgr
->down_rep_recv
.initial_hdr
.lct
,
2070 mgr
->down_rep_recv
.initial_hdr
.rad
[0],
2071 mgr
->down_rep_recv
.msg
[0]);
2072 drm_dp_put_mst_branch_device(mstb
);
2073 memset(&mgr
->down_rep_recv
, 0, sizeof(struct drm_dp_sideband_msg_rx
));
2077 drm_dp_sideband_parse_reply(&mgr
->down_rep_recv
, &txmsg
->reply
);
2078 if (txmsg
->reply
.reply_type
== 1) {
2079 DRM_DEBUG_KMS("Got NAK reply: req 0x%02x, reason 0x%02x, nak data 0x%02x\n", txmsg
->reply
.req_type
, txmsg
->reply
.u
.nak
.reason
, txmsg
->reply
.u
.nak
.nak_data
);
2082 memset(&mgr
->down_rep_recv
, 0, sizeof(struct drm_dp_sideband_msg_rx
));
2083 drm_dp_put_mst_branch_device(mstb
);
2085 mutex_lock(&mgr
->qlock
);
2086 txmsg
->state
= DRM_DP_SIDEBAND_TX_RX
;
2087 mstb
->tx_slots
[slot
] = NULL
;
2088 mutex_unlock(&mgr
->qlock
);
2090 wake_up(&mgr
->tx_waitq
);
2095 static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr
*mgr
)
2098 drm_dp_get_one_sb_msg(mgr
, true);
2100 if (mgr
->up_req_recv
.have_eomt
) {
2101 struct drm_dp_sideband_msg_req_body msg
;
2102 struct drm_dp_mst_branch
*mstb
;
2104 mstb
= drm_dp_get_mst_branch_device(mgr
,
2105 mgr
->up_req_recv
.initial_hdr
.lct
,
2106 mgr
->up_req_recv
.initial_hdr
.rad
);
2108 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr
->up_req_recv
.initial_hdr
.lct
);
2109 memset(&mgr
->up_req_recv
, 0, sizeof(struct drm_dp_sideband_msg_rx
));
2113 seqno
= mgr
->up_req_recv
.initial_hdr
.seqno
;
2114 drm_dp_sideband_parse_req(&mgr
->up_req_recv
, &msg
);
2116 if (msg
.req_type
== DP_CONNECTION_STATUS_NOTIFY
) {
2117 drm_dp_send_up_ack_reply(mgr
, mstb
, msg
.req_type
, seqno
, false);
2118 drm_dp_update_port(mstb
, &msg
.u
.conn_stat
);
2119 DRM_DEBUG_KMS("Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n", msg
.u
.conn_stat
.port_number
, msg
.u
.conn_stat
.legacy_device_plug_status
, msg
.u
.conn_stat
.displayport_device_plug_status
, msg
.u
.conn_stat
.message_capability_status
, msg
.u
.conn_stat
.input_port
, msg
.u
.conn_stat
.peer_device_type
);
2120 (*mgr
->cbs
->hotplug
)(mgr
);
2122 } else if (msg
.req_type
== DP_RESOURCE_STATUS_NOTIFY
) {
2123 drm_dp_send_up_ack_reply(mgr
, mstb
, msg
.req_type
, seqno
, false);
2124 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg
.u
.resource_stat
.port_number
, msg
.u
.resource_stat
.available_pbn
);
2127 drm_dp_put_mst_branch_device(mstb
);
2128 memset(&mgr
->up_req_recv
, 0, sizeof(struct drm_dp_sideband_msg_rx
));
2134 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
2135 * @mgr: manager to notify irq for.
2136 * @esi: 4 bytes from SINK_COUNT_ESI
2137 * @handled: whether the hpd interrupt was consumed or not
2139 * This should be called from the driver when it detects a short IRQ,
2140 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
2141 * topology manager will process the sideband messages received as a result
2144 int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr
*mgr
, u8
*esi
, bool *handled
)
2151 if (sc
!= mgr
->sink_count
) {
2152 mgr
->sink_count
= sc
;
2156 if (esi
[1] & DP_DOWN_REP_MSG_RDY
) {
2157 ret
= drm_dp_mst_handle_down_rep(mgr
);
2161 if (esi
[1] & DP_UP_REQ_MSG_RDY
) {
2162 ret
|= drm_dp_mst_handle_up_req(mgr
);
2166 drm_dp_mst_kick_tx(mgr
);
2169 EXPORT_SYMBOL(drm_dp_mst_hpd_irq
);
2172 * drm_dp_mst_detect_port() - get connection status for an MST port
2173 * @mgr: manager for this port
2174 * @port: unverified pointer to a port
2176 * This returns the current connection state for a port. It validates the
2177 * port pointer still exists so the caller doesn't require a reference
2179 enum drm_connector_status
drm_dp_mst_detect_port(struct drm_connector
*connector
,
2180 struct drm_dp_mst_topology_mgr
*mgr
, struct drm_dp_mst_port
*port
)
2182 enum drm_connector_status status
= connector_status_disconnected
;
2184 /* we need to search for the port in the mgr in case its gone */
2185 port
= drm_dp_get_validated_port_ref(mgr
, port
);
2187 return connector_status_disconnected
;
2192 switch (port
->pdt
) {
2193 case DP_PEER_DEVICE_NONE
:
2194 case DP_PEER_DEVICE_MST_BRANCHING
:
2197 case DP_PEER_DEVICE_SST_SINK
:
2198 status
= connector_status_connected
;
2199 /* for logical ports - cache the EDID */
2200 if (port
->port_num
>= 8 && !port
->cached_edid
) {
2201 port
->cached_edid
= drm_get_edid(connector
, &port
->aux
.ddc
);
2204 case DP_PEER_DEVICE_DP_LEGACY_CONV
:
2206 status
= connector_status_connected
;
2210 drm_dp_put_port(port
);
2213 EXPORT_SYMBOL(drm_dp_mst_detect_port
);
2216 * drm_dp_mst_get_edid() - get EDID for an MST port
2217 * @connector: toplevel connector to get EDID for
2218 * @mgr: manager for this port
2219 * @port: unverified pointer to a port.
2221 * This returns an EDID for the port connected to a connector,
2222 * It validates the pointer still exists so the caller doesn't require a
2225 struct edid
*drm_dp_mst_get_edid(struct drm_connector
*connector
, struct drm_dp_mst_topology_mgr
*mgr
, struct drm_dp_mst_port
*port
)
2227 struct edid
*edid
= NULL
;
2229 /* we need to search for the port in the mgr in case its gone */
2230 port
= drm_dp_get_validated_port_ref(mgr
, port
);
2234 if (port
->cached_edid
)
2235 edid
= drm_edid_duplicate(port
->cached_edid
);
2237 edid
= drm_get_edid(connector
, &port
->aux
.ddc
);
2239 drm_mode_connector_set_tile_property(connector
);
2240 drm_dp_put_port(port
);
2243 EXPORT_SYMBOL(drm_dp_mst_get_edid
);
2246 * drm_dp_find_vcpi_slots() - find slots for this PBN value
2247 * @mgr: manager to use
2248 * @pbn: payload bandwidth to convert into slots.
2250 int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr
*mgr
,
2255 num_slots
= DIV_ROUND_UP(pbn
, mgr
->pbn_div
);
2257 if (num_slots
> mgr
->avail_slots
)
2261 EXPORT_SYMBOL(drm_dp_find_vcpi_slots
);
2263 static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr
*mgr
,
2264 struct drm_dp_vcpi
*vcpi
, int pbn
)
2269 num_slots
= DIV_ROUND_UP(pbn
, mgr
->pbn_div
);
2271 if (num_slots
> mgr
->avail_slots
)
2275 vcpi
->aligned_pbn
= num_slots
* mgr
->pbn_div
;
2276 vcpi
->num_slots
= num_slots
;
2278 ret
= drm_dp_mst_assign_payload_id(mgr
, vcpi
);
2285 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
2286 * @mgr: manager for this port
2287 * @port: port to allocate a virtual channel for.
2288 * @pbn: payload bandwidth number to request
2289 * @slots: returned number of slots for this PBN.
2291 bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr
*mgr
, struct drm_dp_mst_port
*port
, int pbn
, int *slots
)
2295 port
= drm_dp_get_validated_port_ref(mgr
, port
);
2299 if (port
->vcpi
.vcpi
> 0) {
2300 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port
->vcpi
.vcpi
, port
->vcpi
.pbn
, pbn
);
2301 if (pbn
== port
->vcpi
.pbn
) {
2302 *slots
= port
->vcpi
.num_slots
;
2307 ret
= drm_dp_init_vcpi(mgr
, &port
->vcpi
, pbn
);
2309 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn
, mgr
->pbn_div
), mgr
->avail_slots
, ret
);
2312 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn
, port
->vcpi
.num_slots
);
2313 *slots
= port
->vcpi
.num_slots
;
2315 drm_dp_put_port(port
);
2320 EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi
);
2323 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
2324 * @mgr: manager for this port
2325 * @port: unverified pointer to a port.
2327 * This just resets the number of slots for the ports VCPI for later programming.
2329 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr
*mgr
, struct drm_dp_mst_port
*port
)
2331 port
= drm_dp_get_validated_port_ref(mgr
, port
);
2334 port
->vcpi
.num_slots
= 0;
2335 drm_dp_put_port(port
);
2337 EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots
);
2340 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
2341 * @mgr: manager for this port
2342 * @port: unverified port to deallocate vcpi for
2344 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr
*mgr
, struct drm_dp_mst_port
*port
)
2346 port
= drm_dp_get_validated_port_ref(mgr
, port
);
2350 drm_dp_mst_put_payload_id(mgr
, port
->vcpi
.vcpi
);
2351 port
->vcpi
.num_slots
= 0;
2353 port
->vcpi
.aligned_pbn
= 0;
2354 port
->vcpi
.vcpi
= 0;
2355 drm_dp_put_port(port
);
2357 EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi
);
2359 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr
*mgr
,
2360 int id
, struct drm_dp_payload
*payload
)
2362 u8 payload_alloc
[3], status
;
2366 drm_dp_dpcd_writeb(mgr
->aux
, DP_PAYLOAD_TABLE_UPDATE_STATUS
,
2367 DP_PAYLOAD_TABLE_UPDATED
);
2369 payload_alloc
[0] = id
;
2370 payload_alloc
[1] = payload
->start_slot
;
2371 payload_alloc
[2] = payload
->num_slots
;
2373 ret
= drm_dp_dpcd_write(mgr
->aux
, DP_PAYLOAD_ALLOCATE_SET
, payload_alloc
, 3);
2375 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret
);
2380 ret
= drm_dp_dpcd_readb(mgr
->aux
, DP_PAYLOAD_TABLE_UPDATE_STATUS
, &status
);
2382 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret
);
2386 if (!(status
& DP_PAYLOAD_TABLE_UPDATED
)) {
2389 usleep_range(10000, 20000);
2392 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status
);
2403 * drm_dp_check_act_status() - Check ACT handled status.
2404 * @mgr: manager to use
2406 * Check the payload status bits in the DPCD for ACT handled completion.
2408 int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr
*mgr
)
2415 ret
= drm_dp_dpcd_readb(mgr
->aux
, DP_PAYLOAD_TABLE_UPDATE_STATUS
, &status
);
2418 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret
);
2422 if (status
& DP_PAYLOAD_ACT_HANDLED
)
2427 } while (count
< 30);
2429 if (!(status
& DP_PAYLOAD_ACT_HANDLED
)) {
2430 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status
, count
);
2438 EXPORT_SYMBOL(drm_dp_check_act_status
);
2441 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
2442 * @clock: dot clock for the mode
2443 * @bpp: bpp for the mode.
2445 * This uses the formula in the spec to calculate the PBN value for a mode.
2447 int drm_dp_calc_pbn_mode(int clock
, int bpp
)
2452 fixed20_12 margin
, tmp
;
2455 pix_bw
.full
= dfixed_const(clock
);
2456 fbpp
.full
= dfixed_const(bpp
);
2457 tmp
.full
= dfixed_const(8);
2458 fbpp
.full
= dfixed_div(fbpp
, tmp
);
2460 result
.full
= dfixed_mul(pix_bw
, fbpp
);
2461 margin
.full
= dfixed_const(54);
2462 tmp
.full
= dfixed_const(64);
2463 margin
.full
= dfixed_div(margin
, tmp
);
2464 result
.full
= dfixed_div(result
, margin
);
2466 margin
.full
= dfixed_const(1006);
2467 tmp
.full
= dfixed_const(1000);
2468 margin
.full
= dfixed_div(margin
, tmp
);
2469 result
.full
= dfixed_mul(result
, margin
);
2471 result
.full
= dfixed_div(result
, tmp
);
2472 result
.full
= dfixed_ceil(result
);
2473 res
= dfixed_trunc(result
);
2476 EXPORT_SYMBOL(drm_dp_calc_pbn_mode
);
2478 static int test_calc_pbn_mode(void)
2481 ret
= drm_dp_calc_pbn_mode(154000, 30);
2484 ret
= drm_dp_calc_pbn_mode(234000, 30);
2490 /* we want to kick the TX after we've ack the up/down IRQs. */
2491 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr
*mgr
)
2493 queue_work(system_long_wq
, &mgr
->tx_work
);
2496 static void drm_dp_mst_dump_mstb(struct seq_file
*m
,
2497 struct drm_dp_mst_branch
*mstb
)
2499 struct drm_dp_mst_port
*port
;
2500 int tabs
= mstb
->lct
;
2504 for (i
= 0; i
< tabs
; i
++)
2508 seq_printf(m
, "%smst: %p, %d\n", prefix
, mstb
, mstb
->num_ports
);
2509 list_for_each_entry(port
, &mstb
->ports
, next
) {
2510 seq_printf(m
, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix
, port
->port_num
, port
->ddps
, port
->ldps
, port
, port
->connector
);
2512 drm_dp_mst_dump_mstb(m
, port
->mstb
);
2516 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr
*mgr
,
2521 for (i
= 0; i
< 4; i
++) {
2522 ret
= drm_dp_dpcd_read(mgr
->aux
, DP_PAYLOAD_TABLE_UPDATE_STATUS
+ (i
* 16), &buf
[i
* 16], 16);
2532 * drm_dp_mst_dump_topology(): dump topology to seq file.
2533 * @m: seq_file to dump output to
2534 * @mgr: manager to dump current topology for.
2536 * helper to dump MST topology to a seq file for debugfs.
2538 void drm_dp_mst_dump_topology(struct seq_file
*m
,
2539 struct drm_dp_mst_topology_mgr
*mgr
)
2542 struct drm_dp_mst_port
*port
;
2543 mutex_lock(&mgr
->lock
);
2544 if (mgr
->mst_primary
)
2545 drm_dp_mst_dump_mstb(m
, mgr
->mst_primary
);
2548 mutex_unlock(&mgr
->lock
);
2550 mutex_lock(&mgr
->payload_lock
);
2551 seq_printf(m
, "vcpi: %lx %lx\n", mgr
->payload_mask
, mgr
->vcpi_mask
);
2553 for (i
= 0; i
< mgr
->max_payloads
; i
++) {
2554 if (mgr
->proposed_vcpis
[i
]) {
2555 port
= container_of(mgr
->proposed_vcpis
[i
], struct drm_dp_mst_port
, vcpi
);
2556 seq_printf(m
, "vcpi %d: %d %d %d\n", i
, port
->port_num
, port
->vcpi
.vcpi
, port
->vcpi
.num_slots
);
2558 seq_printf(m
, "vcpi %d:unsed\n", i
);
2560 for (i
= 0; i
< mgr
->max_payloads
; i
++) {
2561 seq_printf(m
, "payload %d: %d, %d, %d\n",
2563 mgr
->payloads
[i
].payload_state
,
2564 mgr
->payloads
[i
].start_slot
,
2565 mgr
->payloads
[i
].num_slots
);
2569 mutex_unlock(&mgr
->payload_lock
);
2571 mutex_lock(&mgr
->lock
);
2572 if (mgr
->mst_primary
) {
2576 ret
= drm_dp_dpcd_read(mgr
->aux
, DP_DPCD_REV
, buf
, DP_RECEIVER_CAP_SIZE
);
2577 seq_printf(m
, "dpcd: ");
2578 for (i
= 0; i
< DP_RECEIVER_CAP_SIZE
; i
++)
2579 seq_printf(m
, "%02x ", buf
[i
]);
2580 seq_printf(m
, "\n");
2581 ret
= drm_dp_dpcd_read(mgr
->aux
, DP_FAUX_CAP
, buf
, 2);
2582 seq_printf(m
, "faux/mst: ");
2583 for (i
= 0; i
< 2; i
++)
2584 seq_printf(m
, "%02x ", buf
[i
]);
2585 seq_printf(m
, "\n");
2586 ret
= drm_dp_dpcd_read(mgr
->aux
, DP_MSTM_CTRL
, buf
, 1);
2587 seq_printf(m
, "mst ctrl: ");
2588 for (i
= 0; i
< 1; i
++)
2589 seq_printf(m
, "%02x ", buf
[i
]);
2590 seq_printf(m
, "\n");
2592 bret
= dump_dp_payload_table(mgr
, buf
);
2594 seq_printf(m
, "payload table: ");
2595 for (i
= 0; i
< 63; i
++)
2596 seq_printf(m
, "%02x ", buf
[i
]);
2597 seq_printf(m
, "\n");
2602 mutex_unlock(&mgr
->lock
);
2605 EXPORT_SYMBOL(drm_dp_mst_dump_topology
);
2607 static void drm_dp_tx_work(struct work_struct
*work
)
2609 struct drm_dp_mst_topology_mgr
*mgr
= container_of(work
, struct drm_dp_mst_topology_mgr
, tx_work
);
2611 mutex_lock(&mgr
->qlock
);
2612 if (mgr
->tx_down_in_progress
)
2613 process_single_down_tx_qlock(mgr
);
2614 mutex_unlock(&mgr
->qlock
);
2618 * drm_dp_mst_topology_mgr_init - initialise a topology manager
2619 * @mgr: manager struct to initialise
2620 * @dev: device providing this structure - for i2c addition.
2621 * @aux: DP helper aux channel to talk to this device
2622 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
2623 * @max_payloads: maximum number of payloads this GPU can source
2624 * @conn_base_id: the connector object ID the MST device is connected to.
2626 * Return 0 for success, or negative error code on failure
2628 int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr
*mgr
,
2629 struct device
*dev
, struct drm_dp_aux
*aux
,
2630 int max_dpcd_transaction_bytes
,
2631 int max_payloads
, int conn_base_id
)
2633 mutex_init(&mgr
->lock
);
2634 mutex_init(&mgr
->qlock
);
2635 mutex_init(&mgr
->payload_lock
);
2636 INIT_LIST_HEAD(&mgr
->tx_msg_upq
);
2637 INIT_LIST_HEAD(&mgr
->tx_msg_downq
);
2638 INIT_WORK(&mgr
->work
, drm_dp_mst_link_probe_work
);
2639 INIT_WORK(&mgr
->tx_work
, drm_dp_tx_work
);
2640 init_waitqueue_head(&mgr
->tx_waitq
);
2643 mgr
->max_dpcd_transaction_bytes
= max_dpcd_transaction_bytes
;
2644 mgr
->max_payloads
= max_payloads
;
2645 mgr
->conn_base_id
= conn_base_id
;
2646 mgr
->payloads
= kcalloc(max_payloads
, sizeof(struct drm_dp_payload
), GFP_KERNEL
);
2649 mgr
->proposed_vcpis
= kcalloc(max_payloads
, sizeof(struct drm_dp_vcpi
*), GFP_KERNEL
);
2650 if (!mgr
->proposed_vcpis
)
2652 set_bit(0, &mgr
->payload_mask
);
2653 test_calc_pbn_mode();
2656 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init
);
2659 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
2660 * @mgr: manager to destroy
2662 void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr
*mgr
)
2664 mutex_lock(&mgr
->payload_lock
);
2665 kfree(mgr
->payloads
);
2666 mgr
->payloads
= NULL
;
2667 kfree(mgr
->proposed_vcpis
);
2668 mgr
->proposed_vcpis
= NULL
;
2669 mutex_unlock(&mgr
->payload_lock
);
2673 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy
);
2676 static int drm_dp_mst_i2c_xfer(struct i2c_adapter
*adapter
, struct i2c_msg
*msgs
,
2679 struct drm_dp_aux
*aux
= adapter
->algo_data
;
2680 struct drm_dp_mst_port
*port
= container_of(aux
, struct drm_dp_mst_port
, aux
);
2681 struct drm_dp_mst_branch
*mstb
;
2682 struct drm_dp_mst_topology_mgr
*mgr
= port
->mgr
;
2684 bool reading
= false;
2685 struct drm_dp_sideband_msg_req_body msg
;
2686 struct drm_dp_sideband_msg_tx
*txmsg
= NULL
;
2689 mstb
= drm_dp_get_validated_mstb_ref(mgr
, port
->parent
);
2693 /* construct i2c msg */
2694 /* see if last msg is a read */
2695 if (msgs
[num
- 1].flags
& I2C_M_RD
)
2699 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
2704 msg
.req_type
= DP_REMOTE_I2C_READ
;
2705 msg
.u
.i2c_read
.num_transactions
= num
- 1;
2706 msg
.u
.i2c_read
.port_number
= port
->port_num
;
2707 for (i
= 0; i
< num
- 1; i
++) {
2708 msg
.u
.i2c_read
.transactions
[i
].i2c_dev_id
= msgs
[i
].addr
;
2709 msg
.u
.i2c_read
.transactions
[i
].num_bytes
= msgs
[i
].len
;
2710 msg
.u
.i2c_read
.transactions
[i
].bytes
= msgs
[i
].buf
;
2712 msg
.u
.i2c_read
.read_i2c_device_id
= msgs
[num
- 1].addr
;
2713 msg
.u
.i2c_read
.num_bytes_read
= msgs
[num
- 1].len
;
2715 txmsg
= kzalloc(sizeof(*txmsg
), GFP_KERNEL
);
2722 drm_dp_encode_sideband_req(&msg
, txmsg
);
2724 drm_dp_queue_down_tx(mgr
, txmsg
);
2726 ret
= drm_dp_mst_wait_tx_reply(mstb
, txmsg
);
2729 if (txmsg
->reply
.reply_type
== 1) { /* got a NAK back */
2733 if (txmsg
->reply
.u
.remote_i2c_read_ack
.num_bytes
!= msgs
[num
- 1].len
) {
2737 memcpy(msgs
[num
- 1].buf
, txmsg
->reply
.u
.remote_i2c_read_ack
.bytes
, msgs
[num
- 1].len
);
2742 drm_dp_put_mst_branch_device(mstb
);
2746 static u32
drm_dp_mst_i2c_functionality(struct i2c_adapter
*adapter
)
2748 return I2C_FUNC_I2C
| I2C_FUNC_SMBUS_EMUL
|
2749 I2C_FUNC_SMBUS_READ_BLOCK_DATA
|
2750 I2C_FUNC_SMBUS_BLOCK_PROC_CALL
|
2751 I2C_FUNC_10BIT_ADDR
;
2754 static const struct i2c_algorithm drm_dp_mst_i2c_algo
= {
2755 .functionality
= drm_dp_mst_i2c_functionality
,
2756 .master_xfer
= drm_dp_mst_i2c_xfer
,
2760 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
2761 * @aux: DisplayPort AUX channel
2763 * Returns 0 on success or a negative error code on failure.
2765 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux
*aux
)
2767 aux
->ddc
.algo
= &drm_dp_mst_i2c_algo
;
2768 aux
->ddc
.algo_data
= aux
;
2769 aux
->ddc
.retries
= 3;
2771 aux
->ddc
.class = I2C_CLASS_DDC
;
2772 aux
->ddc
.owner
= THIS_MODULE
;
2773 aux
->ddc
.dev
.parent
= aux
->dev
;
2774 aux
->ddc
.dev
.of_node
= aux
->dev
->of_node
;
2776 strlcpy(aux
->ddc
.name
, aux
->name
? aux
->name
: dev_name(aux
->dev
),
2777 sizeof(aux
->ddc
.name
));
2779 return i2c_add_adapter(&aux
->ddc
);
2783 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
2784 * @aux: DisplayPort AUX channel
2786 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux
*aux
)
2788 i2c_del_adapter(&aux
->ddc
);