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 void 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,
670 u8 number_sdp_streams,
673 struct drm_dp_sideband_msg_req_body req;
674 memset(&req, 0, sizeof(req));
675 req.req_type = DP_ALLOCATE_PAYLOAD;
676 req.u.allocate_payload.port_number = port_num;
677 req.u.allocate_payload.vcpi = vcpi;
678 req.u.allocate_payload.pbn = pbn;
679 req.u.allocate_payload.number_sdp_streams = number_sdp_streams;
680 memcpy(req.u.allocate_payload.sdp_stream_sink, sdp_stream_sink,
682 drm_dp_encode_sideband_req(&req, msg);
683 msg->path_msg = true;
687 static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr,
688 struct drm_dp_vcpi *vcpi)
692 mutex_lock(&mgr->payload_lock);
693 ret = find_first_zero_bit(&mgr->payload_mask, mgr->max_payloads + 1);
694 if (ret > mgr->max_payloads) {
696 DRM_DEBUG_KMS("out of payload ids %d\n", ret);
700 vcpi_ret = find_first_zero_bit(&mgr->vcpi_mask, mgr->max_payloads + 1);
701 if (vcpi_ret > mgr->max_payloads) {
703 DRM_DEBUG_KMS("out of vcpi ids %d\n", ret);
707 set_bit(ret, &mgr->payload_mask);
708 set_bit(vcpi_ret, &mgr->vcpi_mask);
709 vcpi->vcpi = vcpi_ret + 1;
710 mgr->proposed_vcpis[ret - 1] = vcpi;
712 mutex_unlock(&mgr->payload_lock);
716 static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr,
723 mutex_lock(&mgr->payload_lock);
724 DRM_DEBUG_KMS("putting payload %d\n", vcpi);
725 clear_bit(vcpi - 1, &mgr->vcpi_mask);
727 for (i = 0; i < mgr->max_payloads; i++) {
728 if (mgr->proposed_vcpis[i])
729 if (mgr->proposed_vcpis[i]->vcpi == vcpi) {
730 mgr->proposed_vcpis[i] = NULL;
731 clear_bit(i + 1, &mgr->payload_mask);
734 mutex_unlock(&mgr->payload_lock);
737 static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
738 struct drm_dp_sideband_msg_tx *txmsg)
743 * All updates to txmsg->state are protected by mgr->qlock, and the two
744 * cases we check here are terminal states. For those the barriers
745 * provided by the wake_up/wait_event pair are enough.
747 ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX ||
748 txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT);
752 static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
753 struct drm_dp_sideband_msg_tx *txmsg)
755 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
758 ret = wait_event_timeout(mgr->tx_waitq,
759 check_txmsg_state(mgr, txmsg),
761 mutex_lock(&mstb->mgr->qlock);
763 if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) {
768 DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno);
770 /* dump some state */
774 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED ||
775 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) {
776 list_del(&txmsg->next);
779 if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND ||
780 txmsg->state == DRM_DP_SIDEBAND_TX_SENT) {
781 mstb->tx_slots[txmsg->seqno] = NULL;
785 mutex_unlock(&mgr->qlock);
790 static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad)
792 struct drm_dp_mst_branch *mstb;
794 mstb = kzalloc(sizeof(*mstb), GFP_KERNEL);
800 memcpy(mstb->rad, rad, lct / 2);
801 INIT_LIST_HEAD(&mstb->ports);
802 kref_init(&mstb->kref);
806 static void drm_dp_destroy_mst_branch_device(struct kref *kref)
808 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
809 struct drm_dp_mst_port *port, *tmp;
810 bool wake_tx = false;
813 * destroy all ports - don't need lock
814 * as there are no more references to the mst branch
815 * device at this point.
817 list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
818 list_del(&port->next);
819 drm_dp_put_port(port);
822 /* drop any tx slots msg */
823 mutex_lock(&mstb->mgr->qlock);
824 if (mstb->tx_slots[0]) {
825 mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
826 mstb->tx_slots[0] = NULL;
829 if (mstb->tx_slots[1]) {
830 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
831 mstb->tx_slots[1] = NULL;
834 mutex_unlock(&mstb->mgr->qlock);
837 wake_up(&mstb->mgr->tx_waitq);
841 static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb)
843 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device);
847 static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt)
849 struct drm_dp_mst_branch *mstb;
852 case DP_PEER_DEVICE_DP_LEGACY_CONV:
853 case DP_PEER_DEVICE_SST_SINK:
854 /* remove i2c over sideband */
855 drm_dp_mst_unregister_i2c_bus(&port->aux);
857 case DP_PEER_DEVICE_MST_BRANCHING:
860 drm_dp_put_mst_branch_device(mstb);
865 static void drm_dp_destroy_port(struct kref *kref)
867 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
868 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
871 port->vcpi.num_slots = 0;
873 kfree(port->cached_edid);
876 * The only time we don't have a connector
877 * on an output port is if the connector init
880 if (port->connector) {
881 /* we can't destroy the connector here, as
882 * we might be holding the mode_config.mutex
883 * from an EDID retrieval */
885 mutex_lock(&mgr->destroy_connector_lock);
886 list_add(&port->next, &mgr->destroy_connector_list);
887 mutex_unlock(&mgr->destroy_connector_lock);
888 schedule_work(&mgr->destroy_connector_work);
891 /* no need to clean up vcpi
892 * as if we have no connector we never setup a vcpi */
893 drm_dp_port_teardown_pdt(port, port->pdt);
898 static void drm_dp_put_port(struct drm_dp_mst_port *port)
900 kref_put(&port->kref, drm_dp_destroy_port);
903 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)
905 struct drm_dp_mst_port *port;
906 struct drm_dp_mst_branch *rmstb;
907 if (to_find == mstb) {
908 kref_get(&mstb->kref);
911 list_for_each_entry(port, &mstb->ports, next) {
913 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find);
921 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)
923 struct drm_dp_mst_branch *rmstb = NULL;
924 mutex_lock(&mgr->lock);
925 if (mgr->mst_primary)
926 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb);
927 mutex_unlock(&mgr->lock);
931 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)
933 struct drm_dp_mst_port *port, *mport;
935 list_for_each_entry(port, &mstb->ports, next) {
936 if (port == to_find) {
937 kref_get(&port->kref);
941 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find);
949 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)
951 struct drm_dp_mst_port *rport = NULL;
952 mutex_lock(&mgr->lock);
953 if (mgr->mst_primary)
954 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port);
955 mutex_unlock(&mgr->lock);
959 static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num)
961 struct drm_dp_mst_port *port;
963 list_for_each_entry(port, &mstb->ports, next) {
964 if (port->port_num == port_num) {
965 kref_get(&port->kref);
974 * calculate a new RAD for this MST branch device
975 * if parent has an LCT of 2 then it has 1 nibble of RAD,
976 * if parent has an LCT of 3 then it has 2 nibbles of RAD,
978 static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
981 int parent_lct = port->parent->lct;
983 int idx = (parent_lct - 1) / 2;
984 if (parent_lct > 1) {
985 memcpy(rad, port->parent->rad, idx + 1);
986 shift = (parent_lct % 2) ? 4 : 0;
990 rad[idx] |= port->port_num << shift;
991 return parent_lct + 1;
995 * return sends link address for new mstb
997 static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port)
1001 bool send_link = false;
1002 switch (port->pdt) {
1003 case DP_PEER_DEVICE_DP_LEGACY_CONV:
1004 case DP_PEER_DEVICE_SST_SINK:
1005 /* add i2c over sideband */
1006 ret = drm_dp_mst_register_i2c_bus(&port->aux);
1008 case DP_PEER_DEVICE_MST_BRANCHING:
1009 lct = drm_dp_calculate_rad(port, rad);
1011 port->mstb = drm_dp_add_mst_branch_device(lct, rad);
1012 port->mstb->mgr = port->mgr;
1013 port->mstb->port_parent = port;
1021 static void drm_dp_check_port_guid(struct drm_dp_mst_branch *mstb,
1022 struct drm_dp_mst_port *port)
1025 if (port->dpcd_rev >= 0x12) {
1026 port->guid_valid = drm_dp_validate_guid(mstb->mgr, port->guid);
1027 if (!port->guid_valid) {
1028 ret = drm_dp_send_dpcd_write(mstb->mgr,
1032 port->guid_valid = true;
1037 static void build_mst_prop_path(const struct drm_dp_mst_branch *mstb,
1040 size_t proppath_size)
1044 snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id);
1045 for (i = 0; i < (mstb->lct - 1); i++) {
1046 int shift = (i % 2) ? 0 : 4;
1047 int port_num = (mstb->rad[i / 2] >> shift) & 0xf;
1048 snprintf(temp, sizeof(temp), "-%d", port_num);
1049 strlcat(proppath, temp, proppath_size);
1051 snprintf(temp, sizeof(temp), "-%d", pnum);
1052 strlcat(proppath, temp, proppath_size);
1055 static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
1057 struct drm_dp_link_addr_reply_port *port_msg)
1059 struct drm_dp_mst_port *port;
1061 bool created = false;
1064 port = drm_dp_get_port(mstb, port_msg->port_number);
1066 port = kzalloc(sizeof(*port), GFP_KERNEL);
1069 kref_init(&port->kref);
1070 port->parent = mstb;
1071 port->port_num = port_msg->port_number;
1072 port->mgr = mstb->mgr;
1073 port->aux.name = "DPMST";
1074 port->aux.dev = dev;
1077 old_pdt = port->pdt;
1078 old_ddps = port->ddps;
1081 port->pdt = port_msg->peer_device_type;
1082 port->input = port_msg->input_port;
1083 port->mcs = port_msg->mcs;
1084 port->ddps = port_msg->ddps;
1085 port->ldps = port_msg->legacy_device_plug_status;
1086 port->dpcd_rev = port_msg->dpcd_revision;
1087 port->num_sdp_streams = port_msg->num_sdp_streams;
1088 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
1089 memcpy(port->guid, port_msg->peer_guid, 16);
1091 /* manage mstb port lists with mgr lock - take a reference
1094 mutex_lock(&mstb->mgr->lock);
1095 kref_get(&port->kref);
1096 list_add(&port->next, &mstb->ports);
1097 mutex_unlock(&mstb->mgr->lock);
1100 if (old_ddps != port->ddps) {
1102 drm_dp_check_port_guid(mstb, port);
1104 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port);
1106 port->guid_valid = false;
1107 port->available_pbn = 0;
1111 if (old_pdt != port->pdt && !port->input) {
1112 drm_dp_port_teardown_pdt(port, old_pdt);
1114 ret = drm_dp_port_setup_pdt(port);
1116 drm_dp_send_link_address(mstb->mgr, port->mstb);
1119 if (created && !port->input) {
1122 build_mst_prop_path(mstb, port->port_num, proppath, sizeof(proppath));
1123 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath);
1124 if (!port->connector) {
1125 /* remove it from the port list */
1126 mutex_lock(&mstb->mgr->lock);
1127 list_del(&port->next);
1128 mutex_unlock(&mstb->mgr->lock);
1129 /* drop port list reference */
1130 drm_dp_put_port(port);
1133 if (port->port_num >= DP_MST_LOGICAL_PORT_0) {
1134 port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc);
1135 drm_mode_connector_set_tile_property(port->connector);
1137 (*mstb->mgr->cbs->register_connector)(port->connector);
1141 /* put reference to this port */
1142 drm_dp_put_port(port);
1145 static void drm_dp_update_port(struct drm_dp_mst_branch *mstb,
1146 struct drm_dp_connection_status_notify *conn_stat)
1148 struct drm_dp_mst_port *port;
1151 bool dowork = false;
1152 port = drm_dp_get_port(mstb, conn_stat->port_number);
1156 old_ddps = port->ddps;
1157 old_pdt = port->pdt;
1158 port->pdt = conn_stat->peer_device_type;
1159 port->mcs = conn_stat->message_capability_status;
1160 port->ldps = conn_stat->legacy_device_plug_status;
1161 port->ddps = conn_stat->displayport_device_plug_status;
1163 if (old_ddps != port->ddps) {
1165 drm_dp_check_port_guid(mstb, port);
1168 port->guid_valid = false;
1169 port->available_pbn = 0;
1172 if (old_pdt != port->pdt && !port->input) {
1173 drm_dp_port_teardown_pdt(port, old_pdt);
1175 if (drm_dp_port_setup_pdt(port))
1179 drm_dp_put_port(port);
1181 queue_work(system_long_wq, &mstb->mgr->work);
1185 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
1188 struct drm_dp_mst_branch *mstb;
1189 struct drm_dp_mst_port *port;
1191 /* find the port by iterating down */
1193 mutex_lock(&mgr->lock);
1194 mstb = mgr->mst_primary;
1196 for (i = 0; i < lct - 1; i++) {
1197 int shift = (i % 2) ? 0 : 4;
1198 int port_num = (rad[i / 2] >> shift) & 0xf;
1200 list_for_each_entry(port, &mstb->ports, next) {
1201 if (port->port_num == port_num) {
1204 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
1212 kref_get(&mstb->kref);
1214 mutex_unlock(&mgr->lock);
1218 static struct drm_dp_mst_branch *get_mst_branch_device_by_guid_helper(
1219 struct drm_dp_mst_branch *mstb,
1222 struct drm_dp_mst_branch *found_mstb;
1223 struct drm_dp_mst_port *port;
1225 list_for_each_entry(port, &mstb->ports, next) {
1229 if (port->guid_valid && memcmp(port->guid, guid, 16) == 0)
1232 found_mstb = get_mst_branch_device_by_guid_helper(port->mstb, guid);
1241 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device_by_guid(
1242 struct drm_dp_mst_topology_mgr *mgr,
1245 struct drm_dp_mst_branch *mstb;
1247 /* find the port by iterating down */
1248 mutex_lock(&mgr->lock);
1250 if (mgr->guid_valid && memcmp(mgr->guid, guid, 16) == 0)
1251 mstb = mgr->mst_primary;
1253 mstb = get_mst_branch_device_by_guid_helper(mgr->mst_primary, guid);
1256 kref_get(&mstb->kref);
1258 mutex_unlock(&mgr->lock);
1262 static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1263 struct drm_dp_mst_branch *mstb)
1265 struct drm_dp_mst_port *port;
1266 struct drm_dp_mst_branch *mstb_child;
1267 if (!mstb->link_address_sent)
1268 drm_dp_send_link_address(mgr, mstb);
1270 list_for_each_entry(port, &mstb->ports, next) {
1277 if (!port->available_pbn)
1278 drm_dp_send_enum_path_resources(mgr, mstb, port);
1281 mstb_child = drm_dp_get_validated_mstb_ref(mgr, port->mstb);
1283 drm_dp_check_and_send_link_address(mgr, mstb_child);
1284 drm_dp_put_mst_branch_device(mstb_child);
1290 static void drm_dp_mst_link_probe_work(struct work_struct *work)
1292 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
1293 struct drm_dp_mst_branch *mstb;
1295 mutex_lock(&mgr->lock);
1296 mstb = mgr->mst_primary;
1298 kref_get(&mstb->kref);
1300 mutex_unlock(&mgr->lock);
1302 drm_dp_check_and_send_link_address(mgr, mstb);
1303 drm_dp_put_mst_branch_device(mstb);
1307 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
1310 static u8 zero_guid[16];
1312 if (!memcmp(guid, zero_guid, 16)) {
1313 u64 salt = get_jiffies_64();
1314 memcpy(&guid[0], &salt, sizeof(u64));
1315 memcpy(&guid[8], &salt, sizeof(u64));
1322 static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
1324 struct drm_dp_sideband_msg_req_body req;
1326 req.req_type = DP_REMOTE_DPCD_READ;
1327 req.u.dpcd_read.port_number = port_num;
1328 req.u.dpcd_read.dpcd_address = offset;
1329 req.u.dpcd_read.num_bytes = num_bytes;
1330 drm_dp_encode_sideband_req(&req, msg);
1336 static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
1337 bool up, u8 *msg, int len)
1340 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
1341 int tosend, total, offset;
1348 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
1350 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
1353 if (ret != tosend) {
1354 if (ret == -EIO && retries < 5) {
1358 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
1364 } while (total > 0);
1368 static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
1369 struct drm_dp_sideband_msg_tx *txmsg)
1371 struct drm_dp_mst_branch *mstb = txmsg->dst;
1374 /* both msg slots are full */
1375 if (txmsg->seqno == -1) {
1376 if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
1377 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
1380 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
1381 txmsg->seqno = mstb->last_seqno;
1382 mstb->last_seqno ^= 1;
1383 } else if (mstb->tx_slots[0] == NULL)
1387 mstb->tx_slots[txmsg->seqno] = txmsg;
1390 req_type = txmsg->msg[0] & 0x7f;
1391 if (req_type == DP_CONNECTION_STATUS_NOTIFY ||
1392 req_type == DP_RESOURCE_STATUS_NOTIFY)
1396 hdr->path_msg = txmsg->path_msg;
1397 hdr->lct = mstb->lct;
1398 hdr->lcr = mstb->lct - 1;
1400 memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
1401 hdr->seqno = txmsg->seqno;
1405 * process a single block of the next message in the sideband queue
1407 static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1408 struct drm_dp_sideband_msg_tx *txmsg,
1412 struct drm_dp_sideband_msg_hdr hdr;
1413 int len, space, idx, tosend;
1416 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
1418 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
1420 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
1423 /* make hdr from dst mst - for replies use seqno
1424 otherwise assign one */
1425 ret = set_hdr_from_dst_qlock(&hdr, txmsg);
1429 /* amount left to send in this message */
1430 len = txmsg->cur_len - txmsg->cur_offset;
1432 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
1433 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
1435 tosend = min(len, space);
1436 if (len == txmsg->cur_len)
1442 hdr.msg_len = tosend + 1;
1443 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
1444 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
1445 /* add crc at end */
1446 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
1449 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
1451 DRM_DEBUG_KMS("sideband msg failed to send\n");
1455 txmsg->cur_offset += tosend;
1456 if (txmsg->cur_offset == txmsg->cur_len) {
1457 txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
1463 static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1465 struct drm_dp_sideband_msg_tx *txmsg;
1468 WARN_ON(!mutex_is_locked(&mgr->qlock));
1470 /* construct a chunk from the first msg in the tx_msg queue */
1471 if (list_empty(&mgr->tx_msg_downq)) {
1472 mgr->tx_down_in_progress = false;
1475 mgr->tx_down_in_progress = true;
1477 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
1478 ret = process_single_tx_qlock(mgr, txmsg, false);
1480 /* txmsg is sent it should be in the slots now */
1481 list_del(&txmsg->next);
1483 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1484 list_del(&txmsg->next);
1485 if (txmsg->seqno != -1)
1486 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1487 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
1488 wake_up(&mgr->tx_waitq);
1490 if (list_empty(&mgr->tx_msg_downq)) {
1491 mgr->tx_down_in_progress = false;
1496 /* called holding qlock */
1497 static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1498 struct drm_dp_sideband_msg_tx *txmsg)
1502 /* construct a chunk from the first msg in the tx_msg queue */
1503 ret = process_single_tx_qlock(mgr, txmsg, true);
1506 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1508 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1511 static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
1512 struct drm_dp_sideband_msg_tx *txmsg)
1514 mutex_lock(&mgr->qlock);
1515 list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
1516 if (!mgr->tx_down_in_progress)
1517 process_single_down_tx_qlock(mgr);
1518 mutex_unlock(&mgr->qlock);
1521 static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1522 struct drm_dp_mst_branch *mstb)
1525 struct drm_dp_sideband_msg_tx *txmsg;
1528 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1533 len = build_link_address(txmsg);
1535 mstb->link_address_sent = true;
1536 drm_dp_queue_down_tx(mgr, txmsg);
1538 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1542 if (txmsg->reply.reply_type == 1)
1543 DRM_DEBUG_KMS("link address nak received\n");
1545 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
1546 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1547 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,
1548 txmsg->reply.u.link_addr.ports[i].input_port,
1549 txmsg->reply.u.link_addr.ports[i].peer_device_type,
1550 txmsg->reply.u.link_addr.ports[i].port_number,
1551 txmsg->reply.u.link_addr.ports[i].dpcd_revision,
1552 txmsg->reply.u.link_addr.ports[i].mcs,
1553 txmsg->reply.u.link_addr.ports[i].ddps,
1554 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status,
1555 txmsg->reply.u.link_addr.ports[i].num_sdp_streams,
1556 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks);
1558 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1559 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
1561 (*mgr->cbs->hotplug)(mgr);
1564 mstb->link_address_sent = false;
1565 DRM_DEBUG_KMS("link address failed %d\n", ret);
1571 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
1572 struct drm_dp_mst_branch *mstb,
1573 struct drm_dp_mst_port *port)
1576 struct drm_dp_sideband_msg_tx *txmsg;
1579 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1584 len = build_enum_path_resources(txmsg, port->port_num);
1586 drm_dp_queue_down_tx(mgr, txmsg);
1588 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1590 if (txmsg->reply.reply_type == 1)
1591 DRM_DEBUG_KMS("enum path resources nak received\n");
1593 if (port->port_num != txmsg->reply.u.path_resources.port_number)
1594 DRM_ERROR("got incorrect port in response\n");
1595 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,
1596 txmsg->reply.u.path_resources.avail_payload_bw_number);
1597 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number;
1605 static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
1606 struct drm_dp_mst_port *port,
1610 struct drm_dp_sideband_msg_tx *txmsg;
1611 struct drm_dp_mst_branch *mstb;
1613 u8 sinks[DRM_DP_MAX_SDP_STREAMS];
1616 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1620 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1626 for (i = 0; i < port->num_sdp_streams; i++)
1630 len = build_allocate_payload(txmsg, port->port_num,
1632 pbn, port->num_sdp_streams, sinks);
1634 drm_dp_queue_down_tx(mgr, txmsg);
1636 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1638 if (txmsg->reply.reply_type == 1) {
1645 drm_dp_put_mst_branch_device(mstb);
1649 static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1651 struct drm_dp_payload *payload)
1655 ret = drm_dp_dpcd_write_payload(mgr, id, payload);
1657 payload->payload_state = 0;
1660 payload->payload_state = DP_PAYLOAD_LOCAL;
1664 static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1665 struct drm_dp_mst_port *port,
1667 struct drm_dp_payload *payload)
1670 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn);
1673 payload->payload_state = DP_PAYLOAD_REMOTE;
1677 static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1678 struct drm_dp_mst_port *port,
1680 struct drm_dp_payload *payload)
1682 DRM_DEBUG_KMS("\n");
1683 /* its okay for these to fail */
1685 drm_dp_payload_send_msg(mgr, port, id, 0);
1688 drm_dp_dpcd_write_payload(mgr, id, payload);
1689 payload->payload_state = DP_PAYLOAD_DELETE_LOCAL;
1693 static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1695 struct drm_dp_payload *payload)
1697 payload->payload_state = 0;
1702 * drm_dp_update_payload_part1() - Execute payload update part 1
1703 * @mgr: manager to use.
1705 * This iterates over all proposed virtual channels, and tries to
1706 * allocate space in the link for them. For 0->slots transitions,
1707 * this step just writes the VCPI to the MST device. For slots->0
1708 * transitions, this writes the updated VCPIs and removes the
1709 * remote VC payloads.
1711 * after calling this the driver should generate ACT and payload
1714 int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
1718 struct drm_dp_payload req_payload;
1719 struct drm_dp_mst_port *port;
1721 mutex_lock(&mgr->payload_lock);
1722 for (i = 0; i < mgr->max_payloads; i++) {
1723 /* solve the current payloads - compare to the hw ones
1724 - update the hw view */
1725 req_payload.start_slot = cur_slots;
1726 if (mgr->proposed_vcpis[i]) {
1727 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1728 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots;
1729 req_payload.vcpi = mgr->proposed_vcpis[i]->vcpi;
1732 req_payload.num_slots = 0;
1735 if (mgr->payloads[i].start_slot != req_payload.start_slot) {
1736 mgr->payloads[i].start_slot = req_payload.start_slot;
1738 /* work out what is required to happen with this payload */
1739 if (mgr->payloads[i].num_slots != req_payload.num_slots) {
1741 /* need to push an update for this payload */
1742 if (req_payload.num_slots) {
1743 drm_dp_create_payload_step1(mgr, mgr->proposed_vcpis[i]->vcpi, &req_payload);
1744 mgr->payloads[i].num_slots = req_payload.num_slots;
1745 mgr->payloads[i].vcpi = req_payload.vcpi;
1746 } else if (mgr->payloads[i].num_slots) {
1747 mgr->payloads[i].num_slots = 0;
1748 drm_dp_destroy_payload_step1(mgr, port, port->vcpi.vcpi, &mgr->payloads[i]);
1749 req_payload.payload_state = mgr->payloads[i].payload_state;
1750 mgr->payloads[i].start_slot = 0;
1752 mgr->payloads[i].payload_state = req_payload.payload_state;
1754 cur_slots += req_payload.num_slots;
1757 for (i = 0; i < mgr->max_payloads; i++) {
1758 if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1759 DRM_DEBUG_KMS("removing payload %d\n", i);
1760 for (j = i; j < mgr->max_payloads - 1; j++) {
1761 memcpy(&mgr->payloads[j], &mgr->payloads[j + 1], sizeof(struct drm_dp_payload));
1762 mgr->proposed_vcpis[j] = mgr->proposed_vcpis[j + 1];
1763 if (mgr->proposed_vcpis[j] && mgr->proposed_vcpis[j]->num_slots) {
1764 set_bit(j + 1, &mgr->payload_mask);
1766 clear_bit(j + 1, &mgr->payload_mask);
1769 memset(&mgr->payloads[mgr->max_payloads - 1], 0, sizeof(struct drm_dp_payload));
1770 mgr->proposed_vcpis[mgr->max_payloads - 1] = NULL;
1771 clear_bit(mgr->max_payloads, &mgr->payload_mask);
1775 mutex_unlock(&mgr->payload_lock);
1779 EXPORT_SYMBOL(drm_dp_update_payload_part1);
1782 * drm_dp_update_payload_part2() - Execute payload update part 2
1783 * @mgr: manager to use.
1785 * This iterates over all proposed virtual channels, and tries to
1786 * allocate space in the link for them. For 0->slots transitions,
1787 * this step writes the remote VC payload commands. For slots->0
1788 * this just resets some internal state.
1790 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
1792 struct drm_dp_mst_port *port;
1795 mutex_lock(&mgr->payload_lock);
1796 for (i = 0; i < mgr->max_payloads; i++) {
1798 if (!mgr->proposed_vcpis[i])
1801 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1803 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state);
1804 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
1805 ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
1806 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1807 ret = drm_dp_destroy_payload_step2(mgr, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
1810 mutex_unlock(&mgr->payload_lock);
1814 mutex_unlock(&mgr->payload_lock);
1817 EXPORT_SYMBOL(drm_dp_update_payload_part2);
1819 #if 0 /* unused as of yet */
1820 static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
1821 struct drm_dp_mst_port *port,
1822 int offset, int size)
1825 struct drm_dp_sideband_msg_tx *txmsg;
1827 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1831 len = build_dpcd_read(txmsg, port->port_num, 0, 8);
1832 txmsg->dst = port->parent;
1834 drm_dp_queue_down_tx(mgr, txmsg);
1840 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
1841 struct drm_dp_mst_port *port,
1842 int offset, int size, u8 *bytes)
1846 struct drm_dp_sideband_msg_tx *txmsg;
1847 struct drm_dp_mst_branch *mstb;
1849 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1853 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1859 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
1862 drm_dp_queue_down_tx(mgr, txmsg);
1864 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1866 if (txmsg->reply.reply_type == 1) {
1873 drm_dp_put_mst_branch_device(mstb);
1877 static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
1879 struct drm_dp_sideband_msg_reply_body reply;
1881 reply.reply_type = 0;
1882 reply.req_type = req_type;
1883 drm_dp_encode_sideband_reply(&reply, msg);
1887 static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
1888 struct drm_dp_mst_branch *mstb,
1889 int req_type, int seqno, bool broadcast)
1891 struct drm_dp_sideband_msg_tx *txmsg;
1893 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1898 txmsg->seqno = seqno;
1899 drm_dp_encode_up_ack_reply(txmsg, req_type);
1901 mutex_lock(&mgr->qlock);
1903 process_single_up_tx_qlock(mgr, txmsg);
1905 mutex_unlock(&mgr->qlock);
1911 static bool drm_dp_get_vc_payload_bw(int dp_link_bw,
1915 switch (dp_link_bw) {
1917 DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n",
1918 dp_link_bw, dp_link_count);
1921 case DP_LINK_BW_1_62:
1922 *out = 3 * dp_link_count;
1924 case DP_LINK_BW_2_7:
1925 *out = 5 * dp_link_count;
1927 case DP_LINK_BW_5_4:
1928 *out = 10 * dp_link_count;
1935 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
1936 * @mgr: manager to set state for
1937 * @mst_state: true to enable MST on this connector - false to disable.
1939 * This is called by the driver when it detects an MST capable device plugged
1940 * into a DP MST capable port, or when a DP MST capable device is unplugged.
1942 int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
1945 struct drm_dp_mst_branch *mstb = NULL;
1947 mutex_lock(&mgr->lock);
1948 if (mst_state == mgr->mst_state)
1951 mgr->mst_state = mst_state;
1952 /* set the device into MST mode */
1954 WARN_ON(mgr->mst_primary);
1957 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1958 if (ret != DP_RECEIVER_CAP_SIZE) {
1959 DRM_DEBUG_KMS("failed to read DPCD\n");
1963 if (!drm_dp_get_vc_payload_bw(mgr->dpcd[1],
1964 mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK,
1970 mgr->total_pbn = 2560;
1971 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div);
1972 mgr->avail_slots = mgr->total_slots;
1974 /* add initial branch device at LCT 1 */
1975 mstb = drm_dp_add_mst_branch_device(1, NULL);
1982 /* give this the main reference */
1983 mgr->mst_primary = mstb;
1984 kref_get(&mgr->mst_primary->kref);
1987 struct drm_dp_payload reset_pay;
1988 reset_pay.start_slot = 0;
1989 reset_pay.num_slots = 0x3f;
1990 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay);
1993 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1994 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
2001 ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, mgr->guid, 16);
2003 DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret);
2007 mgr->guid_valid = drm_dp_validate_guid(mgr, mgr->guid);
2008 if (!mgr->guid_valid) {
2009 ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, mgr->guid, 16);
2010 mgr->guid_valid = true;
2013 queue_work(system_long_wq, &mgr->work);
2017 /* disable MST on the device */
2018 mstb = mgr->mst_primary;
2019 mgr->mst_primary = NULL;
2020 /* this can fail if the device is gone */
2021 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
2023 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
2024 mgr->payload_mask = 0;
2025 set_bit(0, &mgr->payload_mask);
2030 mutex_unlock(&mgr->lock);
2032 drm_dp_put_mst_branch_device(mstb);
2036 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
2039 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
2040 * @mgr: manager to suspend
2042 * This function tells the MST device that we can't handle UP messages
2043 * anymore. This should stop it from sending any since we are suspended.
2045 void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
2047 mutex_lock(&mgr->lock);
2048 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
2049 DP_MST_EN | DP_UPSTREAM_IS_SRC);
2050 mutex_unlock(&mgr->lock);
2051 flush_work(&mgr->work);
2052 flush_work(&mgr->destroy_connector_work);
2054 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
2057 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
2058 * @mgr: manager to resume
2060 * This will fetch DPCD and see if the device is still there,
2061 * if it is, it will rewrite the MSTM control bits, and return.
2063 * if the device fails this returns -1, and the driver should do
2064 * a full MST reprobe, in case we were undocked.
2066 int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
2070 mutex_lock(&mgr->lock);
2072 if (mgr->mst_primary) {
2074 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
2075 if (sret != DP_RECEIVER_CAP_SIZE) {
2076 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
2081 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
2082 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
2084 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
2093 mutex_unlock(&mgr->lock);
2096 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
2098 static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
2102 int replylen, origlen, curreply;
2104 struct drm_dp_sideband_msg_rx *msg;
2105 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
2106 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv;
2108 len = min(mgr->max_dpcd_transaction_bytes, 16);
2109 ret = drm_dp_dpcd_read(mgr->aux, basereg,
2112 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret);
2115 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true);
2117 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]);
2120 replylen = msg->curchunk_len + msg->curchunk_hdrlen;
2125 while (replylen > 0) {
2126 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
2127 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
2130 DRM_DEBUG_KMS("failed to read a chunk\n");
2132 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false);
2134 DRM_DEBUG_KMS("failed to build sideband msg\n");
2140 static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
2144 drm_dp_get_one_sb_msg(mgr, false);
2146 if (mgr->down_rep_recv.have_eomt) {
2147 struct drm_dp_sideband_msg_tx *txmsg;
2148 struct drm_dp_mst_branch *mstb;
2150 mstb = drm_dp_get_mst_branch_device(mgr,
2151 mgr->down_rep_recv.initial_hdr.lct,
2152 mgr->down_rep_recv.initial_hdr.rad);
2155 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct);
2156 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2160 /* find the message */
2161 slot = mgr->down_rep_recv.initial_hdr.seqno;
2162 mutex_lock(&mgr->qlock);
2163 txmsg = mstb->tx_slots[slot];
2164 /* remove from slots */
2165 mutex_unlock(&mgr->qlock);
2168 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
2170 mgr->down_rep_recv.initial_hdr.seqno,
2171 mgr->down_rep_recv.initial_hdr.lct,
2172 mgr->down_rep_recv.initial_hdr.rad[0],
2173 mgr->down_rep_recv.msg[0]);
2174 drm_dp_put_mst_branch_device(mstb);
2175 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2179 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply);
2180 if (txmsg->reply.reply_type == 1) {
2181 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);
2184 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2185 drm_dp_put_mst_branch_device(mstb);
2187 mutex_lock(&mgr->qlock);
2188 txmsg->state = DRM_DP_SIDEBAND_TX_RX;
2189 mstb->tx_slots[slot] = NULL;
2190 mutex_unlock(&mgr->qlock);
2192 wake_up(&mgr->tx_waitq);
2197 static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
2200 drm_dp_get_one_sb_msg(mgr, true);
2202 if (mgr->up_req_recv.have_eomt) {
2203 struct drm_dp_sideband_msg_req_body msg;
2204 struct drm_dp_mst_branch *mstb = NULL;
2207 if (!mgr->up_req_recv.initial_hdr.broadcast) {
2208 mstb = drm_dp_get_mst_branch_device(mgr,
2209 mgr->up_req_recv.initial_hdr.lct,
2210 mgr->up_req_recv.initial_hdr.rad);
2212 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2213 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2218 seqno = mgr->up_req_recv.initial_hdr.seqno;
2219 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);
2221 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
2222 drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false);
2225 mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.conn_stat.guid);
2228 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2229 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2233 drm_dp_update_port(mstb, &msg.u.conn_stat);
2234 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);
2235 (*mgr->cbs->hotplug)(mgr);
2237 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
2238 drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false);
2240 mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.resource_stat.guid);
2243 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2244 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2248 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
2251 drm_dp_put_mst_branch_device(mstb);
2252 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2258 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
2259 * @mgr: manager to notify irq for.
2260 * @esi: 4 bytes from SINK_COUNT_ESI
2261 * @handled: whether the hpd interrupt was consumed or not
2263 * This should be called from the driver when it detects a short IRQ,
2264 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
2265 * topology manager will process the sideband messages received as a result
2268 int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled)
2275 if (sc != mgr->sink_count) {
2276 mgr->sink_count = sc;
2280 if (esi[1] & DP_DOWN_REP_MSG_RDY) {
2281 ret = drm_dp_mst_handle_down_rep(mgr);
2285 if (esi[1] & DP_UP_REQ_MSG_RDY) {
2286 ret |= drm_dp_mst_handle_up_req(mgr);
2290 drm_dp_mst_kick_tx(mgr);
2293 EXPORT_SYMBOL(drm_dp_mst_hpd_irq);
2296 * drm_dp_mst_detect_port() - get connection status for an MST port
2297 * @mgr: manager for this port
2298 * @port: unverified pointer to a port
2300 * This returns the current connection state for a port. It validates the
2301 * port pointer still exists so the caller doesn't require a reference
2303 enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector,
2304 struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2306 enum drm_connector_status status = connector_status_disconnected;
2308 /* we need to search for the port in the mgr in case its gone */
2309 port = drm_dp_get_validated_port_ref(mgr, port);
2311 return connector_status_disconnected;
2316 switch (port->pdt) {
2317 case DP_PEER_DEVICE_NONE:
2318 case DP_PEER_DEVICE_MST_BRANCHING:
2321 case DP_PEER_DEVICE_SST_SINK:
2322 status = connector_status_connected;
2323 /* for logical ports - cache the EDID */
2324 if (port->port_num >= 8 && !port->cached_edid) {
2325 port->cached_edid = drm_get_edid(connector, &port->aux.ddc);
2328 case DP_PEER_DEVICE_DP_LEGACY_CONV:
2330 status = connector_status_connected;
2334 drm_dp_put_port(port);
2337 EXPORT_SYMBOL(drm_dp_mst_detect_port);
2340 * drm_dp_mst_port_has_audio() - Check whether port has audio capability or not
2341 * @mgr: manager for this port
2342 * @port: unverified pointer to a port.
2344 * This returns whether the port supports audio or not.
2346 bool drm_dp_mst_port_has_audio(struct drm_dp_mst_topology_mgr *mgr,
2347 struct drm_dp_mst_port *port)
2351 port = drm_dp_get_validated_port_ref(mgr, port);
2354 ret = port->has_audio;
2355 drm_dp_put_port(port);
2358 EXPORT_SYMBOL(drm_dp_mst_port_has_audio);
2361 * drm_dp_mst_get_edid() - get EDID for an MST port
2362 * @connector: toplevel connector to get EDID for
2363 * @mgr: manager for this port
2364 * @port: unverified pointer to a port.
2366 * This returns an EDID for the port connected to a connector,
2367 * It validates the pointer still exists so the caller doesn't require a
2370 struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2372 struct edid *edid = NULL;
2374 /* we need to search for the port in the mgr in case its gone */
2375 port = drm_dp_get_validated_port_ref(mgr, port);
2379 if (port->cached_edid)
2380 edid = drm_edid_duplicate(port->cached_edid);
2382 edid = drm_get_edid(connector, &port->aux.ddc);
2383 drm_mode_connector_set_tile_property(connector);
2385 port->has_audio = drm_detect_monitor_audio(edid);
2386 drm_dp_put_port(port);
2389 EXPORT_SYMBOL(drm_dp_mst_get_edid);
2392 * drm_dp_find_vcpi_slots() - find slots for this PBN value
2393 * @mgr: manager to use
2394 * @pbn: payload bandwidth to convert into slots.
2396 int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
2401 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2403 if (num_slots > mgr->avail_slots)
2407 EXPORT_SYMBOL(drm_dp_find_vcpi_slots);
2409 static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
2410 struct drm_dp_vcpi *vcpi, int pbn)
2415 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2417 if (num_slots > mgr->avail_slots)
2421 vcpi->aligned_pbn = num_slots * mgr->pbn_div;
2422 vcpi->num_slots = num_slots;
2424 ret = drm_dp_mst_assign_payload_id(mgr, vcpi);
2431 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
2432 * @mgr: manager for this port
2433 * @port: port to allocate a virtual channel for.
2434 * @pbn: payload bandwidth number to request
2435 * @slots: returned number of slots for this PBN.
2437 bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots)
2441 port = drm_dp_get_validated_port_ref(mgr, port);
2445 if (port->vcpi.vcpi > 0) {
2446 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn);
2447 if (pbn == port->vcpi.pbn) {
2448 *slots = port->vcpi.num_slots;
2453 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn);
2455 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret);
2458 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots);
2459 *slots = port->vcpi.num_slots;
2461 drm_dp_put_port(port);
2466 EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi);
2468 int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2471 port = drm_dp_get_validated_port_ref(mgr, port);
2475 slots = port->vcpi.num_slots;
2476 drm_dp_put_port(port);
2479 EXPORT_SYMBOL(drm_dp_mst_get_vcpi_slots);
2482 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
2483 * @mgr: manager for this port
2484 * @port: unverified pointer to a port.
2486 * This just resets the number of slots for the ports VCPI for later programming.
2488 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2490 port = drm_dp_get_validated_port_ref(mgr, port);
2493 port->vcpi.num_slots = 0;
2494 drm_dp_put_port(port);
2496 EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
2499 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
2500 * @mgr: manager for this port
2501 * @port: unverified port to deallocate vcpi for
2503 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2505 port = drm_dp_get_validated_port_ref(mgr, port);
2509 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2510 port->vcpi.num_slots = 0;
2512 port->vcpi.aligned_pbn = 0;
2513 port->vcpi.vcpi = 0;
2514 drm_dp_put_port(port);
2516 EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi);
2518 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
2519 int id, struct drm_dp_payload *payload)
2521 u8 payload_alloc[3], status;
2525 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
2526 DP_PAYLOAD_TABLE_UPDATED);
2528 payload_alloc[0] = id;
2529 payload_alloc[1] = payload->start_slot;
2530 payload_alloc[2] = payload->num_slots;
2532 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
2534 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret);
2539 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2541 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2545 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
2548 usleep_range(10000, 20000);
2551 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status);
2562 * drm_dp_check_act_status() - Check ACT handled status.
2563 * @mgr: manager to use
2565 * Check the payload status bits in the DPCD for ACT handled completion.
2567 int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
2574 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2577 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2581 if (status & DP_PAYLOAD_ACT_HANDLED)
2586 } while (count < 30);
2588 if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
2589 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count);
2597 EXPORT_SYMBOL(drm_dp_check_act_status);
2600 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
2601 * @clock: dot clock for the mode
2602 * @bpp: bpp for the mode.
2604 * This uses the formula in the spec to calculate the PBN value for a mode.
2606 int drm_dp_calc_pbn_mode(int clock, int bpp)
2611 fixed20_12 margin, tmp;
2614 pix_bw.full = dfixed_const(clock);
2615 fbpp.full = dfixed_const(bpp);
2616 tmp.full = dfixed_const(8);
2617 fbpp.full = dfixed_div(fbpp, tmp);
2619 result.full = dfixed_mul(pix_bw, fbpp);
2620 margin.full = dfixed_const(54);
2621 tmp.full = dfixed_const(64);
2622 margin.full = dfixed_div(margin, tmp);
2623 result.full = dfixed_div(result, margin);
2625 margin.full = dfixed_const(1006);
2626 tmp.full = dfixed_const(1000);
2627 margin.full = dfixed_div(margin, tmp);
2628 result.full = dfixed_mul(result, margin);
2630 result.full = dfixed_div(result, tmp);
2631 result.full = dfixed_ceil(result);
2632 res = dfixed_trunc(result);
2635 EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
2637 static int test_calc_pbn_mode(void)
2640 ret = drm_dp_calc_pbn_mode(154000, 30);
2643 ret = drm_dp_calc_pbn_mode(234000, 30);
2649 /* we want to kick the TX after we've ack the up/down IRQs. */
2650 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
2652 queue_work(system_long_wq, &mgr->tx_work);
2655 static void drm_dp_mst_dump_mstb(struct seq_file *m,
2656 struct drm_dp_mst_branch *mstb)
2658 struct drm_dp_mst_port *port;
2659 int tabs = mstb->lct;
2663 for (i = 0; i < tabs; i++)
2667 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports);
2668 list_for_each_entry(port, &mstb->ports, next) {
2669 seq_printf(m, "%sport: %d: ddps: %d ldps: %d, sdp: %d/%d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port->num_sdp_streams, port->num_sdp_stream_sinks, port, port->connector);
2671 drm_dp_mst_dump_mstb(m, port->mstb);
2675 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
2680 for (i = 0; i < 4; i++) {
2681 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16);
2691 * drm_dp_mst_dump_topology(): dump topology to seq file.
2692 * @m: seq_file to dump output to
2693 * @mgr: manager to dump current topology for.
2695 * helper to dump MST topology to a seq file for debugfs.
2697 void drm_dp_mst_dump_topology(struct seq_file *m,
2698 struct drm_dp_mst_topology_mgr *mgr)
2701 struct drm_dp_mst_port *port;
2702 mutex_lock(&mgr->lock);
2703 if (mgr->mst_primary)
2704 drm_dp_mst_dump_mstb(m, mgr->mst_primary);
2707 mutex_unlock(&mgr->lock);
2709 mutex_lock(&mgr->payload_lock);
2710 seq_printf(m, "vcpi: %lx %lx\n", mgr->payload_mask, mgr->vcpi_mask);
2712 for (i = 0; i < mgr->max_payloads; i++) {
2713 if (mgr->proposed_vcpis[i]) {
2714 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
2715 seq_printf(m, "vcpi %d: %d %d %d\n", i, port->port_num, port->vcpi.vcpi, port->vcpi.num_slots);
2717 seq_printf(m, "vcpi %d:unsed\n", i);
2719 for (i = 0; i < mgr->max_payloads; i++) {
2720 seq_printf(m, "payload %d: %d, %d, %d\n",
2722 mgr->payloads[i].payload_state,
2723 mgr->payloads[i].start_slot,
2724 mgr->payloads[i].num_slots);
2728 mutex_unlock(&mgr->payload_lock);
2730 mutex_lock(&mgr->lock);
2731 if (mgr->mst_primary) {
2735 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
2736 seq_printf(m, "dpcd: ");
2737 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++)
2738 seq_printf(m, "%02x ", buf[i]);
2739 seq_printf(m, "\n");
2740 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
2741 seq_printf(m, "faux/mst: ");
2742 for (i = 0; i < 2; i++)
2743 seq_printf(m, "%02x ", buf[i]);
2744 seq_printf(m, "\n");
2745 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
2746 seq_printf(m, "mst ctrl: ");
2747 for (i = 0; i < 1; i++)
2748 seq_printf(m, "%02x ", buf[i]);
2749 seq_printf(m, "\n");
2751 /* dump the standard OUI branch header */
2752 ret = drm_dp_dpcd_read(mgr->aux, DP_BRANCH_OUI, buf, DP_BRANCH_OUI_HEADER_SIZE);
2753 seq_printf(m, "branch oui: ");
2754 for (i = 0; i < 0x3; i++)
2755 seq_printf(m, "%02x", buf[i]);
2756 seq_printf(m, " devid: ");
2757 for (i = 0x3; i < 0x8; i++)
2758 seq_printf(m, "%c", buf[i]);
2759 seq_printf(m, " revision: hw: %x.%x sw: %x.%x", buf[0x9] >> 4, buf[0x9] & 0xf, buf[0xa], buf[0xb]);
2760 seq_printf(m, "\n");
2761 bret = dump_dp_payload_table(mgr, buf);
2763 seq_printf(m, "payload table: ");
2764 for (i = 0; i < 63; i++)
2765 seq_printf(m, "%02x ", buf[i]);
2766 seq_printf(m, "\n");
2771 mutex_unlock(&mgr->lock);
2774 EXPORT_SYMBOL(drm_dp_mst_dump_topology);
2776 static void drm_dp_tx_work(struct work_struct *work)
2778 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
2780 mutex_lock(&mgr->qlock);
2781 if (mgr->tx_down_in_progress)
2782 process_single_down_tx_qlock(mgr);
2783 mutex_unlock(&mgr->qlock);
2786 static void drm_dp_destroy_connector_work(struct work_struct *work)
2788 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, destroy_connector_work);
2789 struct drm_dp_mst_port *port;
2790 bool send_hotplug = false;
2792 * Not a regular list traverse as we have to drop the destroy
2793 * connector lock before destroying the connector, to avoid AB->BA
2794 * ordering between this lock and the config mutex.
2797 mutex_lock(&mgr->destroy_connector_lock);
2798 port = list_first_entry_or_null(&mgr->destroy_connector_list, struct drm_dp_mst_port, next);
2800 mutex_unlock(&mgr->destroy_connector_lock);
2803 list_del(&port->next);
2804 mutex_unlock(&mgr->destroy_connector_lock);
2806 mgr->cbs->destroy_connector(mgr, port->connector);
2808 drm_dp_port_teardown_pdt(port, port->pdt);
2810 if (!port->input && port->vcpi.vcpi > 0)
2811 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2813 send_hotplug = true;
2816 (*mgr->cbs->hotplug)(mgr);
2820 * drm_dp_mst_topology_mgr_init - initialise a topology manager
2821 * @mgr: manager struct to initialise
2822 * @dev: device providing this structure - for i2c addition.
2823 * @aux: DP helper aux channel to talk to this device
2824 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
2825 * @max_payloads: maximum number of payloads this GPU can source
2826 * @conn_base_id: the connector object ID the MST device is connected to.
2828 * Return 0 for success, or negative error code on failure
2830 int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
2831 struct device *dev, struct drm_dp_aux *aux,
2832 int max_dpcd_transaction_bytes,
2833 int max_payloads, int conn_base_id)
2835 mutex_init(&mgr->lock);
2836 mutex_init(&mgr->qlock);
2837 mutex_init(&mgr->payload_lock);
2838 mutex_init(&mgr->destroy_connector_lock);
2839 INIT_LIST_HEAD(&mgr->tx_msg_downq);
2840 INIT_LIST_HEAD(&mgr->destroy_connector_list);
2841 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
2842 INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
2843 INIT_WORK(&mgr->destroy_connector_work, drm_dp_destroy_connector_work);
2844 init_waitqueue_head(&mgr->tx_waitq);
2847 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
2848 mgr->max_payloads = max_payloads;
2849 mgr->conn_base_id = conn_base_id;
2850 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL);
2853 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL);
2854 if (!mgr->proposed_vcpis)
2856 set_bit(0, &mgr->payload_mask);
2857 test_calc_pbn_mode();
2860 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
2863 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
2864 * @mgr: manager to destroy
2866 void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
2868 flush_work(&mgr->work);
2869 flush_work(&mgr->destroy_connector_work);
2870 mutex_lock(&mgr->payload_lock);
2871 kfree(mgr->payloads);
2872 mgr->payloads = NULL;
2873 kfree(mgr->proposed_vcpis);
2874 mgr->proposed_vcpis = NULL;
2875 mutex_unlock(&mgr->payload_lock);
2879 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
2882 static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
2885 struct drm_dp_aux *aux = adapter->algo_data;
2886 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux);
2887 struct drm_dp_mst_branch *mstb;
2888 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
2890 bool reading = false;
2891 struct drm_dp_sideband_msg_req_body msg;
2892 struct drm_dp_sideband_msg_tx *txmsg = NULL;
2895 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
2899 /* construct i2c msg */
2900 /* see if last msg is a read */
2901 if (msgs[num - 1].flags & I2C_M_RD)
2904 if (!reading || (num - 1 > DP_REMOTE_I2C_READ_MAX_TRANSACTIONS)) {
2905 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
2910 memset(&msg, 0, sizeof(msg));
2911 msg.req_type = DP_REMOTE_I2C_READ;
2912 msg.u.i2c_read.num_transactions = num - 1;
2913 msg.u.i2c_read.port_number = port->port_num;
2914 for (i = 0; i < num - 1; i++) {
2915 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
2916 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
2917 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
2919 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
2920 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
2922 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
2929 drm_dp_encode_sideband_req(&msg, txmsg);
2931 drm_dp_queue_down_tx(mgr, txmsg);
2933 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
2936 if (txmsg->reply.reply_type == 1) { /* got a NAK back */
2940 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
2944 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
2949 drm_dp_put_mst_branch_device(mstb);
2953 static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
2955 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
2956 I2C_FUNC_SMBUS_READ_BLOCK_DATA |
2957 I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
2958 I2C_FUNC_10BIT_ADDR;
2961 static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
2962 .functionality = drm_dp_mst_i2c_functionality,
2963 .master_xfer = drm_dp_mst_i2c_xfer,
2967 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
2968 * @aux: DisplayPort AUX channel
2970 * Returns 0 on success or a negative error code on failure.
2972 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux)
2974 aux->ddc.algo = &drm_dp_mst_i2c_algo;
2975 aux->ddc.algo_data = aux;
2976 aux->ddc.retries = 3;
2978 aux->ddc.class = I2C_CLASS_DDC;
2979 aux->ddc.owner = THIS_MODULE;
2980 aux->ddc.dev.parent = aux->dev;
2981 aux->ddc.dev.of_node = aux->dev->of_node;
2983 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev),
2984 sizeof(aux->ddc.name));
2986 return i2c_add_adapter(&aux->ddc);
2990 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
2991 * @aux: DisplayPort AUX channel
2993 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux)
2995 i2c_del_adapter(&aux->ddc);