1 /* 2 * Copyright © 2014 Red Hat 3 * 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. 13 * 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 20 * OF THIS SOFTWARE. 21 */ 22 23 #include <linux/kernel.h> 24 #include <linux/delay.h> 25 #include <linux/errno.h> 26 #include <linux/sched.h> 27 #include <linux/seq_file.h> 28 #include <linux/i2c.h> 29 #include <drm/drm_dp_mst_helper.h> 30 #include <drm/drmP.h> 31 32 #include <drm/drm_fixed.h> 33 34 /** 35 * DOC: dp mst helper 36 * 37 * These functions contain parts of the DisplayPort 1.2a MultiStream Transport 38 * protocol. The helpers contain a topology manager and bandwidth manager. 39 * The helpers encapsulate the sending and received of sideband msgs. 40 */ 41 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr, 42 char *buf); 43 static int test_calc_pbn_mode(void); 44 45 static void drm_dp_put_port(struct drm_dp_mst_port *port); 46 47 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr, 48 int id, 49 struct drm_dp_payload *payload); 50 51 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr, 52 struct drm_dp_mst_port *port, 53 int offset, int size, u8 *bytes); 54 55 static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr, 56 struct drm_dp_mst_branch *mstb); 57 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr, 58 struct drm_dp_mst_branch *mstb, 59 struct drm_dp_mst_port *port); 60 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr, 61 u8 *guid); 62 63 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux); 64 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux); 65 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr); 66 /* sideband msg handling */ 67 static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles) 68 { 69 u8 bitmask = 0x80; 70 u8 bitshift = 7; 71 u8 array_index = 0; 72 int number_of_bits = num_nibbles * 4; 73 u8 remainder = 0; 74 75 while (number_of_bits != 0) { 76 number_of_bits--; 77 remainder <<= 1; 78 remainder |= (data[array_index] & bitmask) >> bitshift; 79 bitmask >>= 1; 80 bitshift--; 81 if (bitmask == 0) { 82 bitmask = 0x80; 83 bitshift = 7; 84 array_index++; 85 } 86 if ((remainder & 0x10) == 0x10) 87 remainder ^= 0x13; 88 } 89 90 number_of_bits = 4; 91 while (number_of_bits != 0) { 92 number_of_bits--; 93 remainder <<= 1; 94 if ((remainder & 0x10) != 0) 95 remainder ^= 0x13; 96 } 97 98 return remainder; 99 } 100 101 static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes) 102 { 103 u8 bitmask = 0x80; 104 u8 bitshift = 7; 105 u8 array_index = 0; 106 int number_of_bits = number_of_bytes * 8; 107 u16 remainder = 0; 108 109 while (number_of_bits != 0) { 110 number_of_bits--; 111 remainder <<= 1; 112 remainder |= (data[array_index] & bitmask) >> bitshift; 113 bitmask >>= 1; 114 bitshift--; 115 if (bitmask == 0) { 116 bitmask = 0x80; 117 bitshift = 7; 118 array_index++; 119 } 120 if ((remainder & 0x100) == 0x100) 121 remainder ^= 0xd5; 122 } 123 124 number_of_bits = 8; 125 while (number_of_bits != 0) { 126 number_of_bits--; 127 remainder <<= 1; 128 if ((remainder & 0x100) != 0) 129 remainder ^= 0xd5; 130 } 131 132 return remainder & 0xff; 133 } 134 static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr) 135 { 136 u8 size = 3; 137 size += (hdr->lct / 2); 138 return size; 139 } 140 141 static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr, 142 u8 *buf, int *len) 143 { 144 int idx = 0; 145 int i; 146 u8 crc4; 147 buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf); 148 for (i = 0; i < (hdr->lct / 2); i++) 149 buf[idx++] = hdr->rad[i]; 150 buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) | 151 (hdr->msg_len & 0x3f); 152 buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4); 153 154 crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1); 155 buf[idx - 1] |= (crc4 & 0xf); 156 157 *len = idx; 158 } 159 160 static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr, 161 u8 *buf, int buflen, u8 *hdrlen) 162 { 163 u8 crc4; 164 u8 len; 165 int i; 166 u8 idx; 167 if (buf[0] == 0) 168 return false; 169 len = 3; 170 len += ((buf[0] & 0xf0) >> 4) / 2; 171 if (len > buflen) 172 return false; 173 crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1); 174 175 if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) { 176 DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]); 177 return false; 178 } 179 180 hdr->lct = (buf[0] & 0xf0) >> 4; 181 hdr->lcr = (buf[0] & 0xf); 182 idx = 1; 183 for (i = 0; i < (hdr->lct / 2); i++) 184 hdr->rad[i] = buf[idx++]; 185 hdr->broadcast = (buf[idx] >> 7) & 0x1; 186 hdr->path_msg = (buf[idx] >> 6) & 0x1; 187 hdr->msg_len = buf[idx] & 0x3f; 188 idx++; 189 hdr->somt = (buf[idx] >> 7) & 0x1; 190 hdr->eomt = (buf[idx] >> 6) & 0x1; 191 hdr->seqno = (buf[idx] >> 4) & 0x1; 192 idx++; 193 *hdrlen = idx; 194 return true; 195 } 196 197 static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req, 198 struct drm_dp_sideband_msg_tx *raw) 199 { 200 int idx = 0; 201 int i; 202 u8 *buf = raw->msg; 203 buf[idx++] = req->req_type & 0x7f; 204 205 switch (req->req_type) { 206 case DP_ENUM_PATH_RESOURCES: 207 buf[idx] = (req->u.port_num.port_number & 0xf) << 4; 208 idx++; 209 break; 210 case DP_ALLOCATE_PAYLOAD: 211 buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 | 212 (req->u.allocate_payload.number_sdp_streams & 0xf); 213 idx++; 214 buf[idx] = (req->u.allocate_payload.vcpi & 0x7f); 215 idx++; 216 buf[idx] = (req->u.allocate_payload.pbn >> 8); 217 idx++; 218 buf[idx] = (req->u.allocate_payload.pbn & 0xff); 219 idx++; 220 for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) { 221 buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) | 222 (req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf); 223 idx++; 224 } 225 if (req->u.allocate_payload.number_sdp_streams & 1) { 226 i = req->u.allocate_payload.number_sdp_streams - 1; 227 buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4; 228 idx++; 229 } 230 break; 231 case DP_QUERY_PAYLOAD: 232 buf[idx] = (req->u.query_payload.port_number & 0xf) << 4; 233 idx++; 234 buf[idx] = (req->u.query_payload.vcpi & 0x7f); 235 idx++; 236 break; 237 case DP_REMOTE_DPCD_READ: 238 buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4; 239 buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf; 240 idx++; 241 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8; 242 idx++; 243 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff); 244 idx++; 245 buf[idx] = (req->u.dpcd_read.num_bytes); 246 idx++; 247 break; 248 249 case DP_REMOTE_DPCD_WRITE: 250 buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4; 251 buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf; 252 idx++; 253 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8; 254 idx++; 255 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff); 256 idx++; 257 buf[idx] = (req->u.dpcd_write.num_bytes); 258 idx++; 259 memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes); 260 idx += req->u.dpcd_write.num_bytes; 261 break; 262 case DP_REMOTE_I2C_READ: 263 buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4; 264 buf[idx] |= (req->u.i2c_read.num_transactions & 0x3); 265 idx++; 266 for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) { 267 buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f; 268 idx++; 269 buf[idx] = req->u.i2c_read.transactions[i].num_bytes; 270 idx++; 271 memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes); 272 idx += req->u.i2c_read.transactions[i].num_bytes; 273 274 buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5; 275 buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf); 276 idx++; 277 } 278 buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f; 279 idx++; 280 buf[idx] = (req->u.i2c_read.num_bytes_read); 281 idx++; 282 break; 283 284 case DP_REMOTE_I2C_WRITE: 285 buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4; 286 idx++; 287 buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f; 288 idx++; 289 buf[idx] = (req->u.i2c_write.num_bytes); 290 idx++; 291 memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes); 292 idx += req->u.i2c_write.num_bytes; 293 break; 294 } 295 raw->cur_len = idx; 296 } 297 298 static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len) 299 { 300 u8 crc4; 301 crc4 = drm_dp_msg_data_crc4(msg, len); 302 msg[len] = crc4; 303 } 304 305 static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep, 306 struct drm_dp_sideband_msg_tx *raw) 307 { 308 int idx = 0; 309 u8 *buf = raw->msg; 310 311 buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f); 312 313 raw->cur_len = idx; 314 } 315 316 /* this adds a chunk of msg to the builder to get the final msg */ 317 static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg, 318 u8 *replybuf, u8 replybuflen, bool hdr) 319 { 320 int ret; 321 u8 crc4; 322 323 if (hdr) { 324 u8 hdrlen; 325 struct drm_dp_sideband_msg_hdr recv_hdr; 326 ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen); 327 if (ret == false) { 328 #if 0 329 print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false); 330 #endif 331 return false; 332 } 333 334 /* get length contained in this portion */ 335 msg->curchunk_len = recv_hdr.msg_len; 336 msg->curchunk_hdrlen = hdrlen; 337 338 /* we have already gotten an somt - don't bother parsing */ 339 if (recv_hdr.somt && msg->have_somt) 340 return false; 341 342 if (recv_hdr.somt) { 343 memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr)); 344 msg->have_somt = true; 345 } 346 if (recv_hdr.eomt) 347 msg->have_eomt = true; 348 349 /* copy the bytes for the remainder of this header chunk */ 350 msg->curchunk_idx = min(msg->curchunk_len, (u8)(replybuflen - hdrlen)); 351 memcpy(&msg->chunk[0], replybuf + hdrlen, msg->curchunk_idx); 352 } else { 353 memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen); 354 msg->curchunk_idx += replybuflen; 355 } 356 357 if (msg->curchunk_idx >= msg->curchunk_len) { 358 /* do CRC */ 359 crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1); 360 /* copy chunk into bigger msg */ 361 memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1); 362 msg->curlen += msg->curchunk_len - 1; 363 } 364 return true; 365 } 366 367 static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx *raw, 368 struct drm_dp_sideband_msg_reply_body *repmsg) 369 { 370 int idx = 1; 371 int i; 372 memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16); 373 idx += 16; 374 repmsg->u.link_addr.nports = raw->msg[idx] & 0xf; 375 idx++; 376 if (idx > raw->curlen) 377 goto fail_len; 378 for (i = 0; i < repmsg->u.link_addr.nports; i++) { 379 if (raw->msg[idx] & 0x80) 380 repmsg->u.link_addr.ports[i].input_port = 1; 381 382 repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7; 383 repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf); 384 385 idx++; 386 if (idx > raw->curlen) 387 goto fail_len; 388 repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1; 389 repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1; 390 if (repmsg->u.link_addr.ports[i].input_port == 0) 391 repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1; 392 idx++; 393 if (idx > raw->curlen) 394 goto fail_len; 395 if (repmsg->u.link_addr.ports[i].input_port == 0) { 396 repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]); 397 idx++; 398 if (idx > raw->curlen) 399 goto fail_len; 400 memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16); 401 idx += 16; 402 if (idx > raw->curlen) 403 goto fail_len; 404 repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf; 405 repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf); 406 idx++; 407 408 } 409 if (idx > raw->curlen) 410 goto fail_len; 411 } 412 413 return true; 414 fail_len: 415 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen); 416 return false; 417 } 418 419 static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw, 420 struct drm_dp_sideband_msg_reply_body *repmsg) 421 { 422 int idx = 1; 423 repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf; 424 idx++; 425 if (idx > raw->curlen) 426 goto fail_len; 427 repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx]; 428 if (idx > raw->curlen) 429 goto fail_len; 430 431 memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes); 432 return true; 433 fail_len: 434 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen); 435 return false; 436 } 437 438 static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw, 439 struct drm_dp_sideband_msg_reply_body *repmsg) 440 { 441 int idx = 1; 442 repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf; 443 idx++; 444 if (idx > raw->curlen) 445 goto fail_len; 446 return true; 447 fail_len: 448 DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen); 449 return false; 450 } 451 452 static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw, 453 struct drm_dp_sideband_msg_reply_body *repmsg) 454 { 455 int idx = 1; 456 457 repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf); 458 idx++; 459 if (idx > raw->curlen) 460 goto fail_len; 461 repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx]; 462 idx++; 463 /* TODO check */ 464 memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes); 465 return true; 466 fail_len: 467 DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen); 468 return false; 469 } 470 471 static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw, 472 struct drm_dp_sideband_msg_reply_body *repmsg) 473 { 474 int idx = 1; 475 repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf; 476 idx++; 477 if (idx > raw->curlen) 478 goto fail_len; 479 repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]); 480 idx += 2; 481 if (idx > raw->curlen) 482 goto fail_len; 483 repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]); 484 idx += 2; 485 if (idx > raw->curlen) 486 goto fail_len; 487 return true; 488 fail_len: 489 DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen); 490 return false; 491 } 492 493 static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw, 494 struct drm_dp_sideband_msg_reply_body *repmsg) 495 { 496 int idx = 1; 497 repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf; 498 idx++; 499 if (idx > raw->curlen) 500 goto fail_len; 501 repmsg->u.allocate_payload.vcpi = raw->msg[idx]; 502 idx++; 503 if (idx > raw->curlen) 504 goto fail_len; 505 repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]); 506 idx += 2; 507 if (idx > raw->curlen) 508 goto fail_len; 509 return true; 510 fail_len: 511 DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen); 512 return false; 513 } 514 515 static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw, 516 struct drm_dp_sideband_msg_reply_body *repmsg) 517 { 518 int idx = 1; 519 repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf; 520 idx++; 521 if (idx > raw->curlen) 522 goto fail_len; 523 repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]); 524 idx += 2; 525 if (idx > raw->curlen) 526 goto fail_len; 527 return true; 528 fail_len: 529 DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen); 530 return false; 531 } 532 533 static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw, 534 struct drm_dp_sideband_msg_reply_body *msg) 535 { 536 memset(msg, 0, sizeof(*msg)); 537 msg->reply_type = (raw->msg[0] & 0x80) >> 7; 538 msg->req_type = (raw->msg[0] & 0x7f); 539 540 if (msg->reply_type) { 541 memcpy(msg->u.nak.guid, &raw->msg[1], 16); 542 msg->u.nak.reason = raw->msg[17]; 543 msg->u.nak.nak_data = raw->msg[18]; 544 return false; 545 } 546 547 switch (msg->req_type) { 548 case DP_LINK_ADDRESS: 549 return drm_dp_sideband_parse_link_address(raw, msg); 550 case DP_QUERY_PAYLOAD: 551 return drm_dp_sideband_parse_query_payload_ack(raw, msg); 552 case DP_REMOTE_DPCD_READ: 553 return drm_dp_sideband_parse_remote_dpcd_read(raw, msg); 554 case DP_REMOTE_DPCD_WRITE: 555 return drm_dp_sideband_parse_remote_dpcd_write(raw, msg); 556 case DP_REMOTE_I2C_READ: 557 return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg); 558 case DP_ENUM_PATH_RESOURCES: 559 return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg); 560 case DP_ALLOCATE_PAYLOAD: 561 return drm_dp_sideband_parse_allocate_payload_ack(raw, msg); 562 default: 563 DRM_ERROR("Got unknown reply 0x%02x\n", msg->req_type); 564 return false; 565 } 566 } 567 568 static bool drm_dp_sideband_parse_connection_status_notify(struct drm_dp_sideband_msg_rx *raw, 569 struct drm_dp_sideband_msg_req_body *msg) 570 { 571 int idx = 1; 572 573 msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4; 574 idx++; 575 if (idx > raw->curlen) 576 goto fail_len; 577 578 memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16); 579 idx += 16; 580 if (idx > raw->curlen) 581 goto fail_len; 582 583 msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1; 584 msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1; 585 msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1; 586 msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1; 587 msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7); 588 idx++; 589 return true; 590 fail_len: 591 DRM_DEBUG_KMS("connection status reply parse length fail %d %d\n", idx, raw->curlen); 592 return false; 593 } 594 595 static bool drm_dp_sideband_parse_resource_status_notify(struct drm_dp_sideband_msg_rx *raw, 596 struct drm_dp_sideband_msg_req_body *msg) 597 { 598 int idx = 1; 599 600 msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4; 601 idx++; 602 if (idx > raw->curlen) 603 goto fail_len; 604 605 memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16); 606 idx += 16; 607 if (idx > raw->curlen) 608 goto fail_len; 609 610 msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]); 611 idx++; 612 return true; 613 fail_len: 614 DRM_DEBUG_KMS("resource status reply parse length fail %d %d\n", idx, raw->curlen); 615 return false; 616 } 617 618 static bool drm_dp_sideband_parse_req(struct drm_dp_sideband_msg_rx *raw, 619 struct drm_dp_sideband_msg_req_body *msg) 620 { 621 memset(msg, 0, sizeof(*msg)); 622 msg->req_type = (raw->msg[0] & 0x7f); 623 624 switch (msg->req_type) { 625 case DP_CONNECTION_STATUS_NOTIFY: 626 return drm_dp_sideband_parse_connection_status_notify(raw, msg); 627 case DP_RESOURCE_STATUS_NOTIFY: 628 return drm_dp_sideband_parse_resource_status_notify(raw, msg); 629 default: 630 DRM_ERROR("Got unknown request 0x%02x\n", msg->req_type); 631 return false; 632 } 633 } 634 635 static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes) 636 { 637 struct drm_dp_sideband_msg_req_body req; 638 639 req.req_type = DP_REMOTE_DPCD_WRITE; 640 req.u.dpcd_write.port_number = port_num; 641 req.u.dpcd_write.dpcd_address = offset; 642 req.u.dpcd_write.num_bytes = num_bytes; 643 req.u.dpcd_write.bytes = bytes; 644 drm_dp_encode_sideband_req(&req, msg); 645 646 return 0; 647 } 648 649 static int build_link_address(struct drm_dp_sideband_msg_tx *msg) 650 { 651 struct drm_dp_sideband_msg_req_body req; 652 653 req.req_type = DP_LINK_ADDRESS; 654 drm_dp_encode_sideband_req(&req, msg); 655 return 0; 656 } 657 658 static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num) 659 { 660 struct drm_dp_sideband_msg_req_body req; 661 662 req.req_type = DP_ENUM_PATH_RESOURCES; 663 req.u.port_num.port_number = port_num; 664 drm_dp_encode_sideband_req(&req, msg); 665 msg->path_msg = true; 666 return 0; 667 } 668 669 static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num, 670 u8 vcpi, uint16_t pbn, 671 u8 number_sdp_streams, 672 u8 *sdp_stream_sink) 673 { 674 struct drm_dp_sideband_msg_req_body req; 675 memset(&req, 0, sizeof(req)); 676 req.req_type = DP_ALLOCATE_PAYLOAD; 677 req.u.allocate_payload.port_number = port_num; 678 req.u.allocate_payload.vcpi = vcpi; 679 req.u.allocate_payload.pbn = pbn; 680 req.u.allocate_payload.number_sdp_streams = number_sdp_streams; 681 memcpy(req.u.allocate_payload.sdp_stream_sink, sdp_stream_sink, 682 number_sdp_streams); 683 drm_dp_encode_sideband_req(&req, msg); 684 msg->path_msg = true; 685 return 0; 686 } 687 688 static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr, 689 struct drm_dp_vcpi *vcpi) 690 { 691 int ret, vcpi_ret; 692 693 mutex_lock(&mgr->payload_lock); 694 ret = find_first_zero_bit(&mgr->payload_mask, mgr->max_payloads + 1); 695 if (ret > mgr->max_payloads) { 696 ret = -EINVAL; 697 DRM_DEBUG_KMS("out of payload ids %d\n", ret); 698 goto out_unlock; 699 } 700 701 vcpi_ret = find_first_zero_bit(&mgr->vcpi_mask, mgr->max_payloads + 1); 702 if (vcpi_ret > mgr->max_payloads) { 703 ret = -EINVAL; 704 DRM_DEBUG_KMS("out of vcpi ids %d\n", ret); 705 goto out_unlock; 706 } 707 708 set_bit(ret, &mgr->payload_mask); 709 set_bit(vcpi_ret, &mgr->vcpi_mask); 710 vcpi->vcpi = vcpi_ret + 1; 711 mgr->proposed_vcpis[ret - 1] = vcpi; 712 out_unlock: 713 mutex_unlock(&mgr->payload_lock); 714 return ret; 715 } 716 717 static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr, 718 int vcpi) 719 { 720 int i; 721 if (vcpi == 0) 722 return; 723 724 mutex_lock(&mgr->payload_lock); 725 DRM_DEBUG_KMS("putting payload %d\n", vcpi); 726 clear_bit(vcpi - 1, &mgr->vcpi_mask); 727 728 for (i = 0; i < mgr->max_payloads; i++) { 729 if (mgr->proposed_vcpis[i]) 730 if (mgr->proposed_vcpis[i]->vcpi == vcpi) { 731 mgr->proposed_vcpis[i] = NULL; 732 clear_bit(i + 1, &mgr->payload_mask); 733 } 734 } 735 mutex_unlock(&mgr->payload_lock); 736 } 737 738 static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr, 739 struct drm_dp_sideband_msg_tx *txmsg) 740 { 741 bool ret; 742 743 /* 744 * All updates to txmsg->state are protected by mgr->qlock, and the two 745 * cases we check here are terminal states. For those the barriers 746 * provided by the wake_up/wait_event pair are enough. 747 */ 748 ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX || 749 txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT); 750 return ret; 751 } 752 753 static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb, 754 struct drm_dp_sideband_msg_tx *txmsg) 755 { 756 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr; 757 int ret; 758 759 ret = wait_event_timeout(mgr->tx_waitq, 760 check_txmsg_state(mgr, txmsg), 761 (4 * HZ)); 762 mutex_lock(&mstb->mgr->qlock); 763 if (ret > 0) { 764 if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) { 765 ret = -EIO; 766 goto out; 767 } 768 } else { 769 DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno); 770 771 /* dump some state */ 772 ret = -EIO; 773 774 /* remove from q */ 775 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED || 776 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) { 777 list_del(&txmsg->next); 778 } 779 780 if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND || 781 txmsg->state == DRM_DP_SIDEBAND_TX_SENT) { 782 mstb->tx_slots[txmsg->seqno] = NULL; 783 } 784 } 785 out: 786 mutex_unlock(&mgr->qlock); 787 788 return ret; 789 } 790 791 static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad) 792 { 793 struct drm_dp_mst_branch *mstb; 794 795 mstb = kzalloc(sizeof(*mstb), GFP_KERNEL); 796 if (!mstb) 797 return NULL; 798 799 mstb->lct = lct; 800 if (lct > 1) 801 memcpy(mstb->rad, rad, lct / 2); 802 INIT_LIST_HEAD(&mstb->ports); 803 kref_init(&mstb->kref); 804 return mstb; 805 } 806 807 static void drm_dp_free_mst_port(struct kref *kref); 808 809 static void drm_dp_free_mst_branch_device(struct kref *kref) 810 { 811 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref); 812 if (mstb->port_parent) { 813 if (list_empty(&mstb->port_parent->next)) 814 kref_put(&mstb->port_parent->kref, drm_dp_free_mst_port); 815 } 816 kfree(mstb); 817 } 818 819 static void drm_dp_destroy_mst_branch_device(struct kref *kref) 820 { 821 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref); 822 struct drm_dp_mst_port *port, *tmp; 823 bool wake_tx = false; 824 825 /* 826 * init kref again to be used by ports to remove mst branch when it is 827 * not needed anymore 828 */ 829 kref_init(kref); 830 831 if (mstb->port_parent && list_empty(&mstb->port_parent->next)) 832 kref_get(&mstb->port_parent->kref); 833 834 /* 835 * destroy all ports - don't need lock 836 * as there are no more references to the mst branch 837 * device at this point. 838 */ 839 list_for_each_entry_safe(port, tmp, &mstb->ports, next) { 840 list_del(&port->next); 841 drm_dp_put_port(port); 842 } 843 844 /* drop any tx slots msg */ 845 mutex_lock(&mstb->mgr->qlock); 846 if (mstb->tx_slots[0]) { 847 mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT; 848 mstb->tx_slots[0] = NULL; 849 wake_tx = true; 850 } 851 if (mstb->tx_slots[1]) { 852 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT; 853 mstb->tx_slots[1] = NULL; 854 wake_tx = true; 855 } 856 mutex_unlock(&mstb->mgr->qlock); 857 858 if (wake_tx) 859 wake_up(&mstb->mgr->tx_waitq); 860 861 kref_put(kref, drm_dp_free_mst_branch_device); 862 } 863 864 static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb) 865 { 866 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device); 867 } 868 869 870 static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt) 871 { 872 struct drm_dp_mst_branch *mstb; 873 874 switch (old_pdt) { 875 case DP_PEER_DEVICE_DP_LEGACY_CONV: 876 case DP_PEER_DEVICE_SST_SINK: 877 /* remove i2c over sideband */ 878 drm_dp_mst_unregister_i2c_bus(&port->aux); 879 break; 880 case DP_PEER_DEVICE_MST_BRANCHING: 881 mstb = port->mstb; 882 port->mstb = NULL; 883 drm_dp_put_mst_branch_device(mstb); 884 break; 885 } 886 } 887 888 static void drm_dp_destroy_port(struct kref *kref) 889 { 890 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref); 891 struct drm_dp_mst_topology_mgr *mgr = port->mgr; 892 893 if (!port->input) { 894 port->vcpi.num_slots = 0; 895 896 kfree(port->cached_edid); 897 898 /* 899 * The only time we don't have a connector 900 * on an output port is if the connector init 901 * fails. 902 */ 903 if (port->connector) { 904 /* we can't destroy the connector here, as 905 * we might be holding the mode_config.mutex 906 * from an EDID retrieval */ 907 908 mutex_lock(&mgr->destroy_connector_lock); 909 kref_get(&port->parent->kref); 910 list_add(&port->next, &mgr->destroy_connector_list); 911 mutex_unlock(&mgr->destroy_connector_lock); 912 schedule_work(&mgr->destroy_connector_work); 913 return; 914 } 915 /* no need to clean up vcpi 916 * as if we have no connector we never setup a vcpi */ 917 drm_dp_port_teardown_pdt(port, port->pdt); 918 } 919 kfree(port); 920 } 921 922 static void drm_dp_put_port(struct drm_dp_mst_port *port) 923 { 924 kref_put(&port->kref, drm_dp_destroy_port); 925 } 926 927 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) 928 { 929 struct drm_dp_mst_port *port; 930 struct drm_dp_mst_branch *rmstb; 931 if (to_find == mstb) { 932 kref_get(&mstb->kref); 933 return mstb; 934 } 935 list_for_each_entry(port, &mstb->ports, next) { 936 if (port->mstb) { 937 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find); 938 if (rmstb) 939 return rmstb; 940 } 941 } 942 return NULL; 943 } 944 945 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) 946 { 947 struct drm_dp_mst_branch *rmstb = NULL; 948 mutex_lock(&mgr->lock); 949 if (mgr->mst_primary) 950 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb); 951 mutex_unlock(&mgr->lock); 952 return rmstb; 953 } 954 955 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) 956 { 957 struct drm_dp_mst_port *port, *mport; 958 959 list_for_each_entry(port, &mstb->ports, next) { 960 if (port == to_find) { 961 kref_get(&port->kref); 962 return port; 963 } 964 if (port->mstb) { 965 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find); 966 if (mport) 967 return mport; 968 } 969 } 970 return NULL; 971 } 972 973 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) 974 { 975 struct drm_dp_mst_port *rport = NULL; 976 mutex_lock(&mgr->lock); 977 if (mgr->mst_primary) 978 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port); 979 mutex_unlock(&mgr->lock); 980 return rport; 981 } 982 983 static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num) 984 { 985 struct drm_dp_mst_port *port; 986 987 list_for_each_entry(port, &mstb->ports, next) { 988 if (port->port_num == port_num) { 989 kref_get(&port->kref); 990 return port; 991 } 992 } 993 994 return NULL; 995 } 996 997 /* 998 * calculate a new RAD for this MST branch device 999 * if parent has an LCT of 2 then it has 1 nibble of RAD, 1000 * if parent has an LCT of 3 then it has 2 nibbles of RAD, 1001 */ 1002 static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port, 1003 u8 *rad) 1004 { 1005 int parent_lct = port->parent->lct; 1006 int shift = 4; 1007 int idx = (parent_lct - 1) / 2; 1008 if (parent_lct > 1) { 1009 memcpy(rad, port->parent->rad, idx + 1); 1010 shift = (parent_lct % 2) ? 4 : 0; 1011 } else 1012 rad[0] = 0; 1013 1014 rad[idx] |= port->port_num << shift; 1015 return parent_lct + 1; 1016 } 1017 1018 /* 1019 * return sends link address for new mstb 1020 */ 1021 static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port) 1022 { 1023 int ret; 1024 u8 rad[6], lct; 1025 bool send_link = false; 1026 switch (port->pdt) { 1027 case DP_PEER_DEVICE_DP_LEGACY_CONV: 1028 case DP_PEER_DEVICE_SST_SINK: 1029 /* add i2c over sideband */ 1030 ret = drm_dp_mst_register_i2c_bus(&port->aux); 1031 break; 1032 case DP_PEER_DEVICE_MST_BRANCHING: 1033 lct = drm_dp_calculate_rad(port, rad); 1034 1035 port->mstb = drm_dp_add_mst_branch_device(lct, rad); 1036 port->mstb->mgr = port->mgr; 1037 port->mstb->port_parent = port; 1038 1039 send_link = true; 1040 break; 1041 } 1042 return send_link; 1043 } 1044 1045 static void drm_dp_check_mstb_guid(struct drm_dp_mst_branch *mstb, u8 *guid) 1046 { 1047 int ret; 1048 1049 memcpy(mstb->guid, guid, 16); 1050 1051 if (!drm_dp_validate_guid(mstb->mgr, mstb->guid)) { 1052 if (mstb->port_parent) { 1053 ret = drm_dp_send_dpcd_write( 1054 mstb->mgr, 1055 mstb->port_parent, 1056 DP_GUID, 1057 16, 1058 mstb->guid); 1059 } else { 1060 1061 ret = drm_dp_dpcd_write( 1062 mstb->mgr->aux, 1063 DP_GUID, 1064 mstb->guid, 1065 16); 1066 } 1067 } 1068 } 1069 1070 static void build_mst_prop_path(const struct drm_dp_mst_branch *mstb, 1071 int pnum, 1072 char *proppath, 1073 size_t proppath_size) 1074 { 1075 int i; 1076 char temp[8]; 1077 ksnprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id); 1078 for (i = 0; i < (mstb->lct - 1); i++) { 1079 int shift = (i % 2) ? 0 : 4; 1080 int port_num = (mstb->rad[i / 2] >> shift) & 0xf; 1081 ksnprintf(temp, sizeof(temp), "-%d", port_num); 1082 strlcat(proppath, temp, proppath_size); 1083 } 1084 ksnprintf(temp, sizeof(temp), "-%d", pnum); 1085 strlcat(proppath, temp, proppath_size); 1086 } 1087 1088 static void drm_dp_add_port(struct drm_dp_mst_branch *mstb, 1089 struct device *dev, 1090 struct drm_dp_link_addr_reply_port *port_msg) 1091 { 1092 struct drm_dp_mst_port *port; 1093 bool ret; 1094 bool created = false; 1095 int old_pdt = 0; 1096 int old_ddps = 0; 1097 port = drm_dp_get_port(mstb, port_msg->port_number); 1098 if (!port) { 1099 port = kzalloc(sizeof(*port), GFP_KERNEL); 1100 if (!port) 1101 return; 1102 kref_init(&port->kref); 1103 port->parent = mstb; 1104 port->port_num = port_msg->port_number; 1105 port->mgr = mstb->mgr; 1106 port->aux.name = "DPMST"; 1107 port->aux.dev = dev; 1108 created = true; 1109 } else { 1110 old_pdt = port->pdt; 1111 old_ddps = port->ddps; 1112 } 1113 1114 port->pdt = port_msg->peer_device_type; 1115 port->input = port_msg->input_port; 1116 port->mcs = port_msg->mcs; 1117 port->ddps = port_msg->ddps; 1118 port->ldps = port_msg->legacy_device_plug_status; 1119 port->dpcd_rev = port_msg->dpcd_revision; 1120 port->num_sdp_streams = port_msg->num_sdp_streams; 1121 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks; 1122 1123 /* manage mstb port lists with mgr lock - take a reference 1124 for this list */ 1125 if (created) { 1126 mutex_lock(&mstb->mgr->lock); 1127 kref_get(&port->kref); 1128 list_add(&port->next, &mstb->ports); 1129 mutex_unlock(&mstb->mgr->lock); 1130 } 1131 1132 if (old_ddps != port->ddps) { 1133 if (port->ddps) { 1134 if (!port->input) 1135 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port); 1136 } else { 1137 port->available_pbn = 0; 1138 } 1139 } 1140 1141 if (old_pdt != port->pdt && !port->input) { 1142 drm_dp_port_teardown_pdt(port, old_pdt); 1143 1144 ret = drm_dp_port_setup_pdt(port); 1145 if (ret == true) 1146 drm_dp_send_link_address(mstb->mgr, port->mstb); 1147 } 1148 1149 if (created && !port->input) { 1150 char proppath[255]; 1151 1152 build_mst_prop_path(mstb, port->port_num, proppath, sizeof(proppath)); 1153 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath); 1154 if (!port->connector) { 1155 /* remove it from the port list */ 1156 mutex_lock(&mstb->mgr->lock); 1157 list_del(&port->next); 1158 mutex_unlock(&mstb->mgr->lock); 1159 /* drop port list reference */ 1160 drm_dp_put_port(port); 1161 goto out; 1162 } 1163 if (port->port_num >= DP_MST_LOGICAL_PORT_0) { 1164 port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc); 1165 drm_mode_connector_set_tile_property(port->connector); 1166 } 1167 (*mstb->mgr->cbs->register_connector)(port->connector); 1168 } 1169 1170 out: 1171 /* put reference to this port */ 1172 drm_dp_put_port(port); 1173 } 1174 1175 static void drm_dp_update_port(struct drm_dp_mst_branch *mstb, 1176 struct drm_dp_connection_status_notify *conn_stat) 1177 { 1178 struct drm_dp_mst_port *port; 1179 int old_pdt; 1180 int old_ddps; 1181 bool dowork = false; 1182 port = drm_dp_get_port(mstb, conn_stat->port_number); 1183 if (!port) 1184 return; 1185 1186 old_ddps = port->ddps; 1187 old_pdt = port->pdt; 1188 port->pdt = conn_stat->peer_device_type; 1189 port->mcs = conn_stat->message_capability_status; 1190 port->ldps = conn_stat->legacy_device_plug_status; 1191 port->ddps = conn_stat->displayport_device_plug_status; 1192 1193 if (old_ddps != port->ddps) { 1194 if (port->ddps) { 1195 dowork = true; 1196 } else { 1197 port->available_pbn = 0; 1198 } 1199 } 1200 if (old_pdt != port->pdt && !port->input) { 1201 drm_dp_port_teardown_pdt(port, old_pdt); 1202 1203 if (drm_dp_port_setup_pdt(port)) 1204 dowork = true; 1205 } 1206 1207 drm_dp_put_port(port); 1208 if (dowork) 1209 queue_work(system_long_wq, &mstb->mgr->work); 1210 1211 } 1212 1213 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr, 1214 u8 lct, u8 *rad) 1215 { 1216 struct drm_dp_mst_branch *mstb; 1217 struct drm_dp_mst_port *port; 1218 int i; 1219 /* find the port by iterating down */ 1220 1221 mutex_lock(&mgr->lock); 1222 mstb = mgr->mst_primary; 1223 1224 for (i = 0; i < lct - 1; i++) { 1225 int shift = (i % 2) ? 0 : 4; 1226 int port_num = (rad[i / 2] >> shift) & 0xf; 1227 1228 list_for_each_entry(port, &mstb->ports, next) { 1229 if (port->port_num == port_num) { 1230 mstb = port->mstb; 1231 if (!mstb) { 1232 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]); 1233 goto out; 1234 } 1235 1236 break; 1237 } 1238 } 1239 } 1240 kref_get(&mstb->kref); 1241 out: 1242 mutex_unlock(&mgr->lock); 1243 return mstb; 1244 } 1245 1246 static struct drm_dp_mst_branch *get_mst_branch_device_by_guid_helper( 1247 struct drm_dp_mst_branch *mstb, 1248 uint8_t *guid) 1249 { 1250 struct drm_dp_mst_branch *found_mstb; 1251 struct drm_dp_mst_port *port; 1252 1253 if (memcmp(mstb->guid, guid, 16) == 0) 1254 return mstb; 1255 1256 1257 list_for_each_entry(port, &mstb->ports, next) { 1258 if (!port->mstb) 1259 continue; 1260 1261 found_mstb = get_mst_branch_device_by_guid_helper(port->mstb, guid); 1262 1263 if (found_mstb) 1264 return found_mstb; 1265 } 1266 1267 return NULL; 1268 } 1269 1270 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device_by_guid( 1271 struct drm_dp_mst_topology_mgr *mgr, 1272 uint8_t *guid) 1273 { 1274 struct drm_dp_mst_branch *mstb; 1275 1276 /* find the port by iterating down */ 1277 mutex_lock(&mgr->lock); 1278 1279 mstb = get_mst_branch_device_by_guid_helper(mgr->mst_primary, guid); 1280 1281 if (mstb) 1282 kref_get(&mstb->kref); 1283 1284 mutex_unlock(&mgr->lock); 1285 return mstb; 1286 } 1287 1288 static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr, 1289 struct drm_dp_mst_branch *mstb) 1290 { 1291 struct drm_dp_mst_port *port; 1292 struct drm_dp_mst_branch *mstb_child; 1293 if (!mstb->link_address_sent) 1294 drm_dp_send_link_address(mgr, mstb); 1295 1296 list_for_each_entry(port, &mstb->ports, next) { 1297 if (port->input) 1298 continue; 1299 1300 if (!port->ddps) 1301 continue; 1302 1303 if (!port->available_pbn) 1304 drm_dp_send_enum_path_resources(mgr, mstb, port); 1305 1306 if (port->mstb) { 1307 mstb_child = drm_dp_get_validated_mstb_ref(mgr, port->mstb); 1308 if (mstb_child) { 1309 drm_dp_check_and_send_link_address(mgr, mstb_child); 1310 drm_dp_put_mst_branch_device(mstb_child); 1311 } 1312 } 1313 } 1314 } 1315 1316 static void drm_dp_mst_link_probe_work(struct work_struct *work) 1317 { 1318 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work); 1319 struct drm_dp_mst_branch *mstb; 1320 1321 mutex_lock(&mgr->lock); 1322 mstb = mgr->mst_primary; 1323 if (mstb) { 1324 kref_get(&mstb->kref); 1325 } 1326 mutex_unlock(&mgr->lock); 1327 if (mstb) { 1328 drm_dp_check_and_send_link_address(mgr, mstb); 1329 drm_dp_put_mst_branch_device(mstb); 1330 } 1331 } 1332 1333 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr, 1334 u8 *guid) 1335 { 1336 static u8 zero_guid[16]; 1337 1338 if (!memcmp(guid, zero_guid, 16)) { 1339 u64 salt = get_jiffies_64(); 1340 memcpy(&guid[0], &salt, sizeof(u64)); 1341 memcpy(&guid[8], &salt, sizeof(u64)); 1342 return false; 1343 } 1344 return true; 1345 } 1346 1347 #if 0 1348 static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes) 1349 { 1350 struct drm_dp_sideband_msg_req_body req; 1351 1352 req.req_type = DP_REMOTE_DPCD_READ; 1353 req.u.dpcd_read.port_number = port_num; 1354 req.u.dpcd_read.dpcd_address = offset; 1355 req.u.dpcd_read.num_bytes = num_bytes; 1356 drm_dp_encode_sideband_req(&req, msg); 1357 1358 return 0; 1359 } 1360 #endif 1361 1362 static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr, 1363 bool up, u8 *msg, int len) 1364 { 1365 int ret; 1366 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE; 1367 int tosend, total, offset; 1368 int retries = 0; 1369 1370 retry: 1371 total = len; 1372 offset = 0; 1373 do { 1374 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total); 1375 1376 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset, 1377 &msg[offset], 1378 tosend); 1379 if (ret != tosend) { 1380 if (ret == -EIO && retries < 5) { 1381 retries++; 1382 goto retry; 1383 } 1384 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret); 1385 1386 return -EIO; 1387 } 1388 offset += tosend; 1389 total -= tosend; 1390 } while (total > 0); 1391 return 0; 1392 } 1393 1394 static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr, 1395 struct drm_dp_sideband_msg_tx *txmsg) 1396 { 1397 struct drm_dp_mst_branch *mstb = txmsg->dst; 1398 u8 req_type; 1399 1400 /* both msg slots are full */ 1401 if (txmsg->seqno == -1) { 1402 if (mstb->tx_slots[0] && mstb->tx_slots[1]) { 1403 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__); 1404 return -EAGAIN; 1405 } 1406 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) { 1407 txmsg->seqno = mstb->last_seqno; 1408 mstb->last_seqno ^= 1; 1409 } else if (mstb->tx_slots[0] == NULL) 1410 txmsg->seqno = 0; 1411 else 1412 txmsg->seqno = 1; 1413 mstb->tx_slots[txmsg->seqno] = txmsg; 1414 } 1415 1416 req_type = txmsg->msg[0] & 0x7f; 1417 if (req_type == DP_CONNECTION_STATUS_NOTIFY || 1418 req_type == DP_RESOURCE_STATUS_NOTIFY) 1419 hdr->broadcast = 1; 1420 else 1421 hdr->broadcast = 0; 1422 hdr->path_msg = txmsg->path_msg; 1423 hdr->lct = mstb->lct; 1424 hdr->lcr = mstb->lct - 1; 1425 if (mstb->lct > 1) 1426 memcpy(hdr->rad, mstb->rad, mstb->lct / 2); 1427 hdr->seqno = txmsg->seqno; 1428 return 0; 1429 } 1430 /* 1431 * process a single block of the next message in the sideband queue 1432 */ 1433 static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr, 1434 struct drm_dp_sideband_msg_tx *txmsg, 1435 bool up) 1436 { 1437 u8 chunk[48]; 1438 struct drm_dp_sideband_msg_hdr hdr; 1439 int len, space, idx, tosend; 1440 int ret; 1441 1442 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr)); 1443 1444 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) { 1445 txmsg->seqno = -1; 1446 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND; 1447 } 1448 1449 /* make hdr from dst mst - for replies use seqno 1450 otherwise assign one */ 1451 ret = set_hdr_from_dst_qlock(&hdr, txmsg); 1452 if (ret < 0) 1453 return ret; 1454 1455 /* amount left to send in this message */ 1456 len = txmsg->cur_len - txmsg->cur_offset; 1457 1458 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */ 1459 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr); 1460 1461 tosend = min(len, space); 1462 if (len == txmsg->cur_len) 1463 hdr.somt = 1; 1464 if (space >= len) 1465 hdr.eomt = 1; 1466 1467 1468 hdr.msg_len = tosend + 1; 1469 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx); 1470 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend); 1471 /* add crc at end */ 1472 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend); 1473 idx += tosend + 1; 1474 1475 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx); 1476 if (ret) { 1477 DRM_DEBUG_KMS("sideband msg failed to send\n"); 1478 return ret; 1479 } 1480 1481 txmsg->cur_offset += tosend; 1482 if (txmsg->cur_offset == txmsg->cur_len) { 1483 txmsg->state = DRM_DP_SIDEBAND_TX_SENT; 1484 return 1; 1485 } 1486 return 0; 1487 } 1488 1489 static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr) 1490 { 1491 struct drm_dp_sideband_msg_tx *txmsg; 1492 int ret; 1493 1494 WARN_ON(!mutex_is_locked(&mgr->qlock)); 1495 1496 /* construct a chunk from the first msg in the tx_msg queue */ 1497 if (list_empty(&mgr->tx_msg_downq)) { 1498 mgr->tx_down_in_progress = false; 1499 return; 1500 } 1501 mgr->tx_down_in_progress = true; 1502 1503 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next); 1504 ret = process_single_tx_qlock(mgr, txmsg, false); 1505 if (ret == 1) { 1506 /* txmsg is sent it should be in the slots now */ 1507 list_del(&txmsg->next); 1508 } else if (ret) { 1509 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret); 1510 list_del(&txmsg->next); 1511 if (txmsg->seqno != -1) 1512 txmsg->dst->tx_slots[txmsg->seqno] = NULL; 1513 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT; 1514 wake_up(&mgr->tx_waitq); 1515 } 1516 if (list_empty(&mgr->tx_msg_downq)) { 1517 mgr->tx_down_in_progress = false; 1518 return; 1519 } 1520 } 1521 1522 /* called holding qlock */ 1523 static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr, 1524 struct drm_dp_sideband_msg_tx *txmsg) 1525 { 1526 int ret; 1527 1528 /* construct a chunk from the first msg in the tx_msg queue */ 1529 ret = process_single_tx_qlock(mgr, txmsg, true); 1530 1531 if (ret != 1) 1532 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret); 1533 1534 txmsg->dst->tx_slots[txmsg->seqno] = NULL; 1535 } 1536 1537 static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr, 1538 struct drm_dp_sideband_msg_tx *txmsg) 1539 { 1540 mutex_lock(&mgr->qlock); 1541 list_add_tail(&txmsg->next, &mgr->tx_msg_downq); 1542 if (!mgr->tx_down_in_progress) 1543 process_single_down_tx_qlock(mgr); 1544 mutex_unlock(&mgr->qlock); 1545 } 1546 1547 static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr, 1548 struct drm_dp_mst_branch *mstb) 1549 { 1550 int len; 1551 struct drm_dp_sideband_msg_tx *txmsg; 1552 int ret; 1553 1554 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1555 if (!txmsg) 1556 return; 1557 1558 txmsg->dst = mstb; 1559 len = build_link_address(txmsg); 1560 1561 mstb->link_address_sent = true; 1562 drm_dp_queue_down_tx(mgr, txmsg); 1563 1564 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1565 if (ret > 0) { 1566 int i; 1567 1568 if (txmsg->reply.reply_type == 1) 1569 DRM_DEBUG_KMS("link address nak received\n"); 1570 else { 1571 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports); 1572 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) { 1573 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, 1574 txmsg->reply.u.link_addr.ports[i].input_port, 1575 txmsg->reply.u.link_addr.ports[i].peer_device_type, 1576 txmsg->reply.u.link_addr.ports[i].port_number, 1577 txmsg->reply.u.link_addr.ports[i].dpcd_revision, 1578 txmsg->reply.u.link_addr.ports[i].mcs, 1579 txmsg->reply.u.link_addr.ports[i].ddps, 1580 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status, 1581 txmsg->reply.u.link_addr.ports[i].num_sdp_streams, 1582 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks); 1583 } 1584 1585 drm_dp_check_mstb_guid(mstb, txmsg->reply.u.link_addr.guid); 1586 1587 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) { 1588 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]); 1589 } 1590 (*mgr->cbs->hotplug)(mgr); 1591 } 1592 } else { 1593 mstb->link_address_sent = false; 1594 DRM_DEBUG_KMS("link address failed %d\n", ret); 1595 } 1596 1597 kfree(txmsg); 1598 } 1599 1600 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr, 1601 struct drm_dp_mst_branch *mstb, 1602 struct drm_dp_mst_port *port) 1603 { 1604 int len; 1605 struct drm_dp_sideband_msg_tx *txmsg; 1606 int ret; 1607 1608 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1609 if (!txmsg) 1610 return -ENOMEM; 1611 1612 txmsg->dst = mstb; 1613 len = build_enum_path_resources(txmsg, port->port_num); 1614 1615 drm_dp_queue_down_tx(mgr, txmsg); 1616 1617 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1618 if (ret > 0) { 1619 if (txmsg->reply.reply_type == 1) 1620 DRM_DEBUG_KMS("enum path resources nak received\n"); 1621 else { 1622 if (port->port_num != txmsg->reply.u.path_resources.port_number) 1623 DRM_ERROR("got incorrect port in response\n"); 1624 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, 1625 txmsg->reply.u.path_resources.avail_payload_bw_number); 1626 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number; 1627 } 1628 } 1629 1630 kfree(txmsg); 1631 return 0; 1632 } 1633 1634 static struct drm_dp_mst_port *drm_dp_get_last_connected_port_to_mstb(struct drm_dp_mst_branch *mstb) 1635 { 1636 if (!mstb->port_parent) 1637 return NULL; 1638 1639 if (mstb->port_parent->mstb != mstb) 1640 return mstb->port_parent; 1641 1642 return drm_dp_get_last_connected_port_to_mstb(mstb->port_parent->parent); 1643 } 1644 1645 static struct drm_dp_mst_branch *drm_dp_get_last_connected_port_and_mstb(struct drm_dp_mst_topology_mgr *mgr, 1646 struct drm_dp_mst_branch *mstb, 1647 int *port_num) 1648 { 1649 struct drm_dp_mst_branch *rmstb = NULL; 1650 struct drm_dp_mst_port *found_port; 1651 mutex_lock(&mgr->lock); 1652 if (mgr->mst_primary) { 1653 found_port = drm_dp_get_last_connected_port_to_mstb(mstb); 1654 1655 if (found_port) { 1656 rmstb = found_port->parent; 1657 kref_get(&rmstb->kref); 1658 *port_num = found_port->port_num; 1659 } 1660 } 1661 mutex_unlock(&mgr->lock); 1662 return rmstb; 1663 } 1664 1665 static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr, 1666 struct drm_dp_mst_port *port, 1667 int id, 1668 int pbn) 1669 { 1670 struct drm_dp_sideband_msg_tx *txmsg; 1671 struct drm_dp_mst_branch *mstb; 1672 int len, ret, port_num; 1673 u8 sinks[DRM_DP_MAX_SDP_STREAMS]; 1674 int i; 1675 1676 port = drm_dp_get_validated_port_ref(mgr, port); 1677 if (!port) 1678 return -EINVAL; 1679 1680 port_num = port->port_num; 1681 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent); 1682 if (!mstb) { 1683 mstb = drm_dp_get_last_connected_port_and_mstb(mgr, port->parent, &port_num); 1684 1685 if (!mstb) { 1686 drm_dp_put_port(port); 1687 return -EINVAL; 1688 } 1689 } 1690 1691 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1692 if (!txmsg) { 1693 ret = -ENOMEM; 1694 goto fail_put; 1695 } 1696 1697 for (i = 0; i < port->num_sdp_streams; i++) 1698 sinks[i] = i; 1699 1700 txmsg->dst = mstb; 1701 len = build_allocate_payload(txmsg, port_num, 1702 id, 1703 pbn, port->num_sdp_streams, sinks); 1704 1705 drm_dp_queue_down_tx(mgr, txmsg); 1706 1707 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1708 if (ret > 0) { 1709 if (txmsg->reply.reply_type == 1) { 1710 ret = -EINVAL; 1711 } else 1712 ret = 0; 1713 } 1714 kfree(txmsg); 1715 fail_put: 1716 drm_dp_put_mst_branch_device(mstb); 1717 drm_dp_put_port(port); 1718 return ret; 1719 } 1720 1721 static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr, 1722 int id, 1723 struct drm_dp_payload *payload) 1724 { 1725 int ret; 1726 1727 ret = drm_dp_dpcd_write_payload(mgr, id, payload); 1728 if (ret < 0) { 1729 payload->payload_state = 0; 1730 return ret; 1731 } 1732 payload->payload_state = DP_PAYLOAD_LOCAL; 1733 return 0; 1734 } 1735 1736 static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr, 1737 struct drm_dp_mst_port *port, 1738 int id, 1739 struct drm_dp_payload *payload) 1740 { 1741 int ret; 1742 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn); 1743 if (ret < 0) 1744 return ret; 1745 payload->payload_state = DP_PAYLOAD_REMOTE; 1746 return ret; 1747 } 1748 1749 static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr, 1750 struct drm_dp_mst_port *port, 1751 int id, 1752 struct drm_dp_payload *payload) 1753 { 1754 DRM_DEBUG_KMS("\n"); 1755 /* its okay for these to fail */ 1756 if (port) { 1757 drm_dp_payload_send_msg(mgr, port, id, 0); 1758 } 1759 1760 drm_dp_dpcd_write_payload(mgr, id, payload); 1761 payload->payload_state = DP_PAYLOAD_DELETE_LOCAL; 1762 return 0; 1763 } 1764 1765 static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr, 1766 int id, 1767 struct drm_dp_payload *payload) 1768 { 1769 payload->payload_state = 0; 1770 return 0; 1771 } 1772 1773 /** 1774 * drm_dp_update_payload_part1() - Execute payload update part 1 1775 * @mgr: manager to use. 1776 * 1777 * This iterates over all proposed virtual channels, and tries to 1778 * allocate space in the link for them. For 0->slots transitions, 1779 * this step just writes the VCPI to the MST device. For slots->0 1780 * transitions, this writes the updated VCPIs and removes the 1781 * remote VC payloads. 1782 * 1783 * after calling this the driver should generate ACT and payload 1784 * packets. 1785 */ 1786 int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr) 1787 { 1788 int i, j; 1789 int cur_slots = 1; 1790 struct drm_dp_payload req_payload; 1791 struct drm_dp_mst_port *port; 1792 1793 mutex_lock(&mgr->payload_lock); 1794 for (i = 0; i < mgr->max_payloads; i++) { 1795 /* solve the current payloads - compare to the hw ones 1796 - update the hw view */ 1797 req_payload.start_slot = cur_slots; 1798 if (mgr->proposed_vcpis[i]) { 1799 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi); 1800 port = drm_dp_get_validated_port_ref(mgr, port); 1801 if (!port) { 1802 mutex_unlock(&mgr->payload_lock); 1803 return -EINVAL; 1804 } 1805 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots; 1806 req_payload.vcpi = mgr->proposed_vcpis[i]->vcpi; 1807 } else { 1808 port = NULL; 1809 req_payload.num_slots = 0; 1810 } 1811 1812 if (mgr->payloads[i].start_slot != req_payload.start_slot) { 1813 mgr->payloads[i].start_slot = req_payload.start_slot; 1814 } 1815 /* work out what is required to happen with this payload */ 1816 if (mgr->payloads[i].num_slots != req_payload.num_slots) { 1817 1818 /* need to push an update for this payload */ 1819 if (req_payload.num_slots) { 1820 drm_dp_create_payload_step1(mgr, mgr->proposed_vcpis[i]->vcpi, &req_payload); 1821 mgr->payloads[i].num_slots = req_payload.num_slots; 1822 mgr->payloads[i].vcpi = req_payload.vcpi; 1823 } else if (mgr->payloads[i].num_slots) { 1824 mgr->payloads[i].num_slots = 0; 1825 drm_dp_destroy_payload_step1(mgr, port, port->vcpi.vcpi, &mgr->payloads[i]); 1826 req_payload.payload_state = mgr->payloads[i].payload_state; 1827 mgr->payloads[i].start_slot = 0; 1828 } 1829 mgr->payloads[i].payload_state = req_payload.payload_state; 1830 } 1831 cur_slots += req_payload.num_slots; 1832 1833 if (port) 1834 drm_dp_put_port(port); 1835 } 1836 1837 for (i = 0; i < mgr->max_payloads; i++) { 1838 if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) { 1839 DRM_DEBUG_KMS("removing payload %d\n", i); 1840 for (j = i; j < mgr->max_payloads - 1; j++) { 1841 memcpy(&mgr->payloads[j], &mgr->payloads[j + 1], sizeof(struct drm_dp_payload)); 1842 mgr->proposed_vcpis[j] = mgr->proposed_vcpis[j + 1]; 1843 if (mgr->proposed_vcpis[j] && mgr->proposed_vcpis[j]->num_slots) { 1844 set_bit(j + 1, &mgr->payload_mask); 1845 } else { 1846 clear_bit(j + 1, &mgr->payload_mask); 1847 } 1848 } 1849 memset(&mgr->payloads[mgr->max_payloads - 1], 0, sizeof(struct drm_dp_payload)); 1850 mgr->proposed_vcpis[mgr->max_payloads - 1] = NULL; 1851 clear_bit(mgr->max_payloads, &mgr->payload_mask); 1852 1853 } 1854 } 1855 mutex_unlock(&mgr->payload_lock); 1856 1857 return 0; 1858 } 1859 EXPORT_SYMBOL(drm_dp_update_payload_part1); 1860 1861 /** 1862 * drm_dp_update_payload_part2() - Execute payload update part 2 1863 * @mgr: manager to use. 1864 * 1865 * This iterates over all proposed virtual channels, and tries to 1866 * allocate space in the link for them. For 0->slots transitions, 1867 * this step writes the remote VC payload commands. For slots->0 1868 * this just resets some internal state. 1869 */ 1870 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr) 1871 { 1872 struct drm_dp_mst_port *port; 1873 int i; 1874 int ret = 0; 1875 mutex_lock(&mgr->payload_lock); 1876 for (i = 0; i < mgr->max_payloads; i++) { 1877 1878 if (!mgr->proposed_vcpis[i]) 1879 continue; 1880 1881 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi); 1882 1883 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state); 1884 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) { 1885 ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]); 1886 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) { 1887 ret = drm_dp_destroy_payload_step2(mgr, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]); 1888 } 1889 if (ret) { 1890 mutex_unlock(&mgr->payload_lock); 1891 return ret; 1892 } 1893 } 1894 mutex_unlock(&mgr->payload_lock); 1895 return 0; 1896 } 1897 EXPORT_SYMBOL(drm_dp_update_payload_part2); 1898 1899 #if 0 /* unused as of yet */ 1900 static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr, 1901 struct drm_dp_mst_port *port, 1902 int offset, int size) 1903 { 1904 int len; 1905 struct drm_dp_sideband_msg_tx *txmsg; 1906 1907 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1908 if (!txmsg) 1909 return -ENOMEM; 1910 1911 len = build_dpcd_read(txmsg, port->port_num, 0, 8); 1912 txmsg->dst = port->parent; 1913 1914 drm_dp_queue_down_tx(mgr, txmsg); 1915 1916 return 0; 1917 } 1918 #endif 1919 1920 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr, 1921 struct drm_dp_mst_port *port, 1922 int offset, int size, u8 *bytes) 1923 { 1924 int len; 1925 int ret; 1926 struct drm_dp_sideband_msg_tx *txmsg; 1927 struct drm_dp_mst_branch *mstb; 1928 1929 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent); 1930 if (!mstb) 1931 return -EINVAL; 1932 1933 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1934 if (!txmsg) { 1935 ret = -ENOMEM; 1936 goto fail_put; 1937 } 1938 1939 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes); 1940 txmsg->dst = mstb; 1941 1942 drm_dp_queue_down_tx(mgr, txmsg); 1943 1944 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1945 if (ret > 0) { 1946 if (txmsg->reply.reply_type == 1) { 1947 ret = -EINVAL; 1948 } else 1949 ret = 0; 1950 } 1951 kfree(txmsg); 1952 fail_put: 1953 drm_dp_put_mst_branch_device(mstb); 1954 return ret; 1955 } 1956 1957 static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type) 1958 { 1959 struct drm_dp_sideband_msg_reply_body reply; 1960 1961 reply.reply_type = 0; 1962 reply.req_type = req_type; 1963 drm_dp_encode_sideband_reply(&reply, msg); 1964 return 0; 1965 } 1966 1967 static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr, 1968 struct drm_dp_mst_branch *mstb, 1969 int req_type, int seqno, bool broadcast) 1970 { 1971 struct drm_dp_sideband_msg_tx *txmsg; 1972 1973 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1974 if (!txmsg) 1975 return -ENOMEM; 1976 1977 txmsg->dst = mstb; 1978 txmsg->seqno = seqno; 1979 drm_dp_encode_up_ack_reply(txmsg, req_type); 1980 1981 mutex_lock(&mgr->qlock); 1982 1983 process_single_up_tx_qlock(mgr, txmsg); 1984 1985 mutex_unlock(&mgr->qlock); 1986 1987 kfree(txmsg); 1988 return 0; 1989 } 1990 1991 static bool drm_dp_get_vc_payload_bw(int dp_link_bw, 1992 int dp_link_count, 1993 int *out) 1994 { 1995 switch (dp_link_bw) { 1996 default: 1997 DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n", 1998 dp_link_bw, dp_link_count); 1999 return false; 2000 2001 case DP_LINK_BW_1_62: 2002 *out = 3 * dp_link_count; 2003 break; 2004 case DP_LINK_BW_2_7: 2005 *out = 5 * dp_link_count; 2006 break; 2007 case DP_LINK_BW_5_4: 2008 *out = 10 * dp_link_count; 2009 break; 2010 } 2011 return true; 2012 } 2013 2014 /** 2015 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager 2016 * @mgr: manager to set state for 2017 * @mst_state: true to enable MST on this connector - false to disable. 2018 * 2019 * This is called by the driver when it detects an MST capable device plugged 2020 * into a DP MST capable port, or when a DP MST capable device is unplugged. 2021 */ 2022 int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state) 2023 { 2024 int ret = 0; 2025 struct drm_dp_mst_branch *mstb = NULL; 2026 2027 mutex_lock(&mgr->lock); 2028 if (mst_state == mgr->mst_state) 2029 goto out_unlock; 2030 2031 mgr->mst_state = mst_state; 2032 /* set the device into MST mode */ 2033 if (mst_state) { 2034 WARN_ON(mgr->mst_primary); 2035 2036 /* get dpcd info */ 2037 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE); 2038 if (ret != DP_RECEIVER_CAP_SIZE) { 2039 DRM_DEBUG_KMS("failed to read DPCD\n"); 2040 goto out_unlock; 2041 } 2042 2043 if (!drm_dp_get_vc_payload_bw(mgr->dpcd[1], 2044 mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK, 2045 &mgr->pbn_div)) { 2046 ret = -EINVAL; 2047 goto out_unlock; 2048 } 2049 2050 mgr->total_pbn = 2560; 2051 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div); 2052 mgr->avail_slots = mgr->total_slots; 2053 2054 /* add initial branch device at LCT 1 */ 2055 mstb = drm_dp_add_mst_branch_device(1, NULL); 2056 if (mstb == NULL) { 2057 ret = -ENOMEM; 2058 goto out_unlock; 2059 } 2060 mstb->mgr = mgr; 2061 2062 /* give this the main reference */ 2063 mgr->mst_primary = mstb; 2064 kref_get(&mgr->mst_primary->kref); 2065 2066 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 2067 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); 2068 if (ret < 0) { 2069 goto out_unlock; 2070 } 2071 2072 { 2073 struct drm_dp_payload reset_pay; 2074 reset_pay.start_slot = 0; 2075 reset_pay.num_slots = 0x3f; 2076 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay); 2077 } 2078 2079 queue_work(system_long_wq, &mgr->work); 2080 2081 ret = 0; 2082 } else { 2083 /* disable MST on the device */ 2084 mstb = mgr->mst_primary; 2085 mgr->mst_primary = NULL; 2086 /* this can fail if the device is gone */ 2087 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0); 2088 ret = 0; 2089 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload)); 2090 mgr->payload_mask = 0; 2091 set_bit(0, &mgr->payload_mask); 2092 mgr->vcpi_mask = 0; 2093 } 2094 2095 out_unlock: 2096 mutex_unlock(&mgr->lock); 2097 if (mstb) 2098 drm_dp_put_mst_branch_device(mstb); 2099 return ret; 2100 2101 } 2102 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst); 2103 2104 /** 2105 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager 2106 * @mgr: manager to suspend 2107 * 2108 * This function tells the MST device that we can't handle UP messages 2109 * anymore. This should stop it from sending any since we are suspended. 2110 */ 2111 void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr) 2112 { 2113 mutex_lock(&mgr->lock); 2114 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 2115 DP_MST_EN | DP_UPSTREAM_IS_SRC); 2116 mutex_unlock(&mgr->lock); 2117 flush_work(&mgr->work); 2118 flush_work(&mgr->destroy_connector_work); 2119 } 2120 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend); 2121 2122 /** 2123 * drm_dp_mst_topology_mgr_resume() - resume the MST manager 2124 * @mgr: manager to resume 2125 * 2126 * This will fetch DPCD and see if the device is still there, 2127 * if it is, it will rewrite the MSTM control bits, and return. 2128 * 2129 * if the device fails this returns -1, and the driver should do 2130 * a full MST reprobe, in case we were undocked. 2131 */ 2132 int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr) 2133 { 2134 int ret = 0; 2135 2136 mutex_lock(&mgr->lock); 2137 2138 if (mgr->mst_primary) { 2139 int sret; 2140 u8 guid[16]; 2141 2142 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE); 2143 if (sret != DP_RECEIVER_CAP_SIZE) { 2144 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n"); 2145 ret = -1; 2146 goto out_unlock; 2147 } 2148 2149 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 2150 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); 2151 if (ret < 0) { 2152 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n"); 2153 ret = -1; 2154 goto out_unlock; 2155 } 2156 2157 /* Some hubs forget their guids after they resume */ 2158 sret = drm_dp_dpcd_read(mgr->aux, DP_GUID, guid, 16); 2159 if (sret != 16) { 2160 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n"); 2161 ret = -1; 2162 goto out_unlock; 2163 } 2164 drm_dp_check_mstb_guid(mgr->mst_primary, guid); 2165 2166 ret = 0; 2167 } else 2168 ret = -1; 2169 2170 out_unlock: 2171 mutex_unlock(&mgr->lock); 2172 return ret; 2173 } 2174 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume); 2175 2176 static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up) 2177 { 2178 int len; 2179 u8 replyblock[32]; 2180 int replylen, origlen, curreply; 2181 int ret; 2182 struct drm_dp_sideband_msg_rx *msg; 2183 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE; 2184 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv; 2185 2186 len = min(mgr->max_dpcd_transaction_bytes, 16); 2187 ret = drm_dp_dpcd_read(mgr->aux, basereg, 2188 replyblock, len); 2189 if (ret != len) { 2190 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret); 2191 return; 2192 } 2193 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true); 2194 if (!ret) { 2195 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]); 2196 return; 2197 } 2198 replylen = msg->curchunk_len + msg->curchunk_hdrlen; 2199 2200 origlen = replylen; 2201 replylen -= len; 2202 curreply = len; 2203 while (replylen > 0) { 2204 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16); 2205 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply, 2206 replyblock, len); 2207 if (ret != len) { 2208 DRM_DEBUG_KMS("failed to read a chunk\n"); 2209 } 2210 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false); 2211 if (ret == false) 2212 DRM_DEBUG_KMS("failed to build sideband msg\n"); 2213 curreply += len; 2214 replylen -= len; 2215 } 2216 } 2217 2218 static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr) 2219 { 2220 int ret = 0; 2221 2222 drm_dp_get_one_sb_msg(mgr, false); 2223 2224 if (mgr->down_rep_recv.have_eomt) { 2225 struct drm_dp_sideband_msg_tx *txmsg; 2226 struct drm_dp_mst_branch *mstb; 2227 int slot = -1; 2228 mstb = drm_dp_get_mst_branch_device(mgr, 2229 mgr->down_rep_recv.initial_hdr.lct, 2230 mgr->down_rep_recv.initial_hdr.rad); 2231 2232 if (!mstb) { 2233 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct); 2234 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2235 return 0; 2236 } 2237 2238 /* find the message */ 2239 slot = mgr->down_rep_recv.initial_hdr.seqno; 2240 mutex_lock(&mgr->qlock); 2241 txmsg = mstb->tx_slots[slot]; 2242 /* remove from slots */ 2243 mutex_unlock(&mgr->qlock); 2244 2245 if (!txmsg) { 2246 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n", 2247 mstb, 2248 mgr->down_rep_recv.initial_hdr.seqno, 2249 mgr->down_rep_recv.initial_hdr.lct, 2250 mgr->down_rep_recv.initial_hdr.rad[0], 2251 mgr->down_rep_recv.msg[0]); 2252 drm_dp_put_mst_branch_device(mstb); 2253 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2254 return 0; 2255 } 2256 2257 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply); 2258 if (txmsg->reply.reply_type == 1) { 2259 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); 2260 } 2261 2262 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2263 drm_dp_put_mst_branch_device(mstb); 2264 2265 mutex_lock(&mgr->qlock); 2266 txmsg->state = DRM_DP_SIDEBAND_TX_RX; 2267 mstb->tx_slots[slot] = NULL; 2268 mutex_unlock(&mgr->qlock); 2269 2270 wake_up(&mgr->tx_waitq); 2271 } 2272 return ret; 2273 } 2274 2275 static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr) 2276 { 2277 int ret = 0; 2278 drm_dp_get_one_sb_msg(mgr, true); 2279 2280 if (mgr->up_req_recv.have_eomt) { 2281 struct drm_dp_sideband_msg_req_body msg; 2282 struct drm_dp_mst_branch *mstb = NULL; 2283 bool seqno; 2284 2285 if (!mgr->up_req_recv.initial_hdr.broadcast) { 2286 mstb = drm_dp_get_mst_branch_device(mgr, 2287 mgr->up_req_recv.initial_hdr.lct, 2288 mgr->up_req_recv.initial_hdr.rad); 2289 if (!mstb) { 2290 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct); 2291 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2292 return 0; 2293 } 2294 } 2295 2296 seqno = mgr->up_req_recv.initial_hdr.seqno; 2297 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg); 2298 2299 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) { 2300 drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false); 2301 2302 if (!mstb) 2303 mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.conn_stat.guid); 2304 2305 if (!mstb) { 2306 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct); 2307 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2308 return 0; 2309 } 2310 2311 drm_dp_update_port(mstb, &msg.u.conn_stat); 2312 2313 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); 2314 (*mgr->cbs->hotplug)(mgr); 2315 2316 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) { 2317 drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false); 2318 if (!mstb) 2319 mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.resource_stat.guid); 2320 2321 if (!mstb) { 2322 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct); 2323 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2324 return 0; 2325 } 2326 2327 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn); 2328 } 2329 2330 drm_dp_put_mst_branch_device(mstb); 2331 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2332 } 2333 return ret; 2334 } 2335 2336 /** 2337 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify 2338 * @mgr: manager to notify irq for. 2339 * @esi: 4 bytes from SINK_COUNT_ESI 2340 * @handled: whether the hpd interrupt was consumed or not 2341 * 2342 * This should be called from the driver when it detects a short IRQ, 2343 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The 2344 * topology manager will process the sideband messages received as a result 2345 * of this. 2346 */ 2347 int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled) 2348 { 2349 int ret = 0; 2350 int sc; 2351 *handled = false; 2352 sc = esi[0] & 0x3f; 2353 2354 if (sc != mgr->sink_count) { 2355 mgr->sink_count = sc; 2356 *handled = true; 2357 } 2358 2359 if (esi[1] & DP_DOWN_REP_MSG_RDY) { 2360 ret = drm_dp_mst_handle_down_rep(mgr); 2361 *handled = true; 2362 } 2363 2364 if (esi[1] & DP_UP_REQ_MSG_RDY) { 2365 ret |= drm_dp_mst_handle_up_req(mgr); 2366 *handled = true; 2367 } 2368 2369 drm_dp_mst_kick_tx(mgr); 2370 return ret; 2371 } 2372 EXPORT_SYMBOL(drm_dp_mst_hpd_irq); 2373 2374 /** 2375 * drm_dp_mst_detect_port() - get connection status for an MST port 2376 * @mgr: manager for this port 2377 * @port: unverified pointer to a port 2378 * 2379 * This returns the current connection state for a port. It validates the 2380 * port pointer still exists so the caller doesn't require a reference 2381 */ 2382 enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector, 2383 struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2384 { 2385 enum drm_connector_status status = connector_status_disconnected; 2386 2387 /* we need to search for the port in the mgr in case its gone */ 2388 port = drm_dp_get_validated_port_ref(mgr, port); 2389 if (!port) 2390 return connector_status_disconnected; 2391 2392 if (!port->ddps) 2393 goto out; 2394 2395 switch (port->pdt) { 2396 case DP_PEER_DEVICE_NONE: 2397 case DP_PEER_DEVICE_MST_BRANCHING: 2398 break; 2399 2400 case DP_PEER_DEVICE_SST_SINK: 2401 status = connector_status_connected; 2402 /* for logical ports - cache the EDID */ 2403 if (port->port_num >= 8 && !port->cached_edid) { 2404 port->cached_edid = drm_get_edid(connector, &port->aux.ddc); 2405 } 2406 break; 2407 case DP_PEER_DEVICE_DP_LEGACY_CONV: 2408 if (port->ldps) 2409 status = connector_status_connected; 2410 break; 2411 } 2412 out: 2413 drm_dp_put_port(port); 2414 return status; 2415 } 2416 EXPORT_SYMBOL(drm_dp_mst_detect_port); 2417 2418 /** 2419 * drm_dp_mst_port_has_audio() - Check whether port has audio capability or not 2420 * @mgr: manager for this port 2421 * @port: unverified pointer to a port. 2422 * 2423 * This returns whether the port supports audio or not. 2424 */ 2425 bool drm_dp_mst_port_has_audio(struct drm_dp_mst_topology_mgr *mgr, 2426 struct drm_dp_mst_port *port) 2427 { 2428 bool ret = false; 2429 2430 port = drm_dp_get_validated_port_ref(mgr, port); 2431 if (!port) 2432 return ret; 2433 ret = port->has_audio; 2434 drm_dp_put_port(port); 2435 return ret; 2436 } 2437 EXPORT_SYMBOL(drm_dp_mst_port_has_audio); 2438 2439 /** 2440 * drm_dp_mst_get_edid() - get EDID for an MST port 2441 * @connector: toplevel connector to get EDID for 2442 * @mgr: manager for this port 2443 * @port: unverified pointer to a port. 2444 * 2445 * This returns an EDID for the port connected to a connector, 2446 * It validates the pointer still exists so the caller doesn't require a 2447 * reference. 2448 */ 2449 struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2450 { 2451 struct edid *edid = NULL; 2452 2453 /* we need to search for the port in the mgr in case its gone */ 2454 port = drm_dp_get_validated_port_ref(mgr, port); 2455 if (!port) 2456 return NULL; 2457 2458 if (port->cached_edid) 2459 edid = drm_edid_duplicate(port->cached_edid); 2460 else { 2461 edid = drm_get_edid(connector, &port->aux.ddc); 2462 drm_mode_connector_set_tile_property(connector); 2463 } 2464 port->has_audio = drm_detect_monitor_audio(edid); 2465 drm_dp_put_port(port); 2466 return edid; 2467 } 2468 EXPORT_SYMBOL(drm_dp_mst_get_edid); 2469 2470 /** 2471 * drm_dp_find_vcpi_slots() - find slots for this PBN value 2472 * @mgr: manager to use 2473 * @pbn: payload bandwidth to convert into slots. 2474 */ 2475 int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, 2476 int pbn) 2477 { 2478 int num_slots; 2479 2480 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div); 2481 2482 if (num_slots > mgr->avail_slots) 2483 return -ENOSPC; 2484 return num_slots; 2485 } 2486 EXPORT_SYMBOL(drm_dp_find_vcpi_slots); 2487 2488 static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr, 2489 struct drm_dp_vcpi *vcpi, int pbn) 2490 { 2491 int num_slots; 2492 int ret; 2493 2494 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div); 2495 2496 if (num_slots > mgr->avail_slots) 2497 return -ENOSPC; 2498 2499 vcpi->pbn = pbn; 2500 vcpi->aligned_pbn = num_slots * mgr->pbn_div; 2501 vcpi->num_slots = num_slots; 2502 2503 ret = drm_dp_mst_assign_payload_id(mgr, vcpi); 2504 if (ret < 0) 2505 return ret; 2506 return 0; 2507 } 2508 2509 /** 2510 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel 2511 * @mgr: manager for this port 2512 * @port: port to allocate a virtual channel for. 2513 * @pbn: payload bandwidth number to request 2514 * @slots: returned number of slots for this PBN. 2515 */ 2516 bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots) 2517 { 2518 int ret; 2519 2520 port = drm_dp_get_validated_port_ref(mgr, port); 2521 if (!port) 2522 return false; 2523 2524 if (port->vcpi.vcpi > 0) { 2525 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn); 2526 if (pbn == port->vcpi.pbn) { 2527 *slots = port->vcpi.num_slots; 2528 drm_dp_put_port(port); 2529 return true; 2530 } 2531 } 2532 2533 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn); 2534 if (ret) { 2535 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret); 2536 goto out; 2537 } 2538 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots); 2539 *slots = port->vcpi.num_slots; 2540 2541 drm_dp_put_port(port); 2542 return true; 2543 out: 2544 return false; 2545 } 2546 EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi); 2547 2548 int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2549 { 2550 int slots = 0; 2551 port = drm_dp_get_validated_port_ref(mgr, port); 2552 if (!port) 2553 return slots; 2554 2555 slots = port->vcpi.num_slots; 2556 drm_dp_put_port(port); 2557 return slots; 2558 } 2559 EXPORT_SYMBOL(drm_dp_mst_get_vcpi_slots); 2560 2561 /** 2562 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI 2563 * @mgr: manager for this port 2564 * @port: unverified pointer to a port. 2565 * 2566 * This just resets the number of slots for the ports VCPI for later programming. 2567 */ 2568 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2569 { 2570 port = drm_dp_get_validated_port_ref(mgr, port); 2571 if (!port) 2572 return; 2573 port->vcpi.num_slots = 0; 2574 drm_dp_put_port(port); 2575 } 2576 EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots); 2577 2578 /** 2579 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI 2580 * @mgr: manager for this port 2581 * @port: unverified port to deallocate vcpi for 2582 */ 2583 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2584 { 2585 port = drm_dp_get_validated_port_ref(mgr, port); 2586 if (!port) 2587 return; 2588 2589 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi); 2590 port->vcpi.num_slots = 0; 2591 port->vcpi.pbn = 0; 2592 port->vcpi.aligned_pbn = 0; 2593 port->vcpi.vcpi = 0; 2594 drm_dp_put_port(port); 2595 } 2596 EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi); 2597 2598 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr, 2599 int id, struct drm_dp_payload *payload) 2600 { 2601 u8 payload_alloc[3], status; 2602 int ret; 2603 int retries = 0; 2604 2605 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, 2606 DP_PAYLOAD_TABLE_UPDATED); 2607 2608 payload_alloc[0] = id; 2609 payload_alloc[1] = payload->start_slot; 2610 payload_alloc[2] = payload->num_slots; 2611 2612 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3); 2613 if (ret != 3) { 2614 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret); 2615 goto fail; 2616 } 2617 2618 retry: 2619 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status); 2620 if (ret < 0) { 2621 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret); 2622 goto fail; 2623 } 2624 2625 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) { 2626 retries++; 2627 if (retries < 20) { 2628 usleep_range(10000, 20000); 2629 goto retry; 2630 } 2631 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status); 2632 ret = -EINVAL; 2633 goto fail; 2634 } 2635 ret = 0; 2636 fail: 2637 return ret; 2638 } 2639 2640 2641 /** 2642 * drm_dp_check_act_status() - Check ACT handled status. 2643 * @mgr: manager to use 2644 * 2645 * Check the payload status bits in the DPCD for ACT handled completion. 2646 */ 2647 int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr) 2648 { 2649 u8 status; 2650 int ret; 2651 int count = 0; 2652 2653 do { 2654 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status); 2655 2656 if (ret < 0) { 2657 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret); 2658 goto fail; 2659 } 2660 2661 if (status & DP_PAYLOAD_ACT_HANDLED) 2662 break; 2663 count++; 2664 udelay(100); 2665 2666 } while (count < 30); 2667 2668 if (!(status & DP_PAYLOAD_ACT_HANDLED)) { 2669 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count); 2670 ret = -EINVAL; 2671 goto fail; 2672 } 2673 return 0; 2674 fail: 2675 return ret; 2676 } 2677 EXPORT_SYMBOL(drm_dp_check_act_status); 2678 2679 /** 2680 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode. 2681 * @clock: dot clock for the mode 2682 * @bpp: bpp for the mode. 2683 * 2684 * This uses the formula in the spec to calculate the PBN value for a mode. 2685 */ 2686 int drm_dp_calc_pbn_mode(int clock, int bpp) 2687 { 2688 u64 kbps; 2689 s64 peak_kbps; 2690 u32 numerator; 2691 u32 denominator; 2692 2693 kbps = clock * bpp; 2694 2695 /* 2696 * margin 5300ppm + 300ppm ~ 0.6% as per spec, factor is 1.006 2697 * The unit of 54/64Mbytes/sec is an arbitrary unit chosen based on 2698 * common multiplier to render an integer PBN for all link rate/lane 2699 * counts combinations 2700 * calculate 2701 * peak_kbps *= (1006/1000) 2702 * peak_kbps *= (64/54) 2703 * peak_kbps *= 8 convert to bytes 2704 */ 2705 2706 numerator = 64 * 1006; 2707 denominator = 54 * 8 * 1000 * 1000; 2708 2709 kbps *= numerator; 2710 peak_kbps = drm_fixp_from_fraction(kbps, denominator); 2711 2712 return drm_fixp2int_ceil(peak_kbps); 2713 } 2714 EXPORT_SYMBOL(drm_dp_calc_pbn_mode); 2715 2716 static int test_calc_pbn_mode(void) 2717 { 2718 int ret; 2719 ret = drm_dp_calc_pbn_mode(154000, 30); 2720 if (ret != 689) { 2721 DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n", 2722 154000, 30, 689, ret); 2723 return -EINVAL; 2724 } 2725 ret = drm_dp_calc_pbn_mode(234000, 30); 2726 if (ret != 1047) { 2727 DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n", 2728 234000, 30, 1047, ret); 2729 return -EINVAL; 2730 } 2731 ret = drm_dp_calc_pbn_mode(297000, 24); 2732 if (ret != 1063) { 2733 DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n", 2734 297000, 24, 1063, ret); 2735 return -EINVAL; 2736 } 2737 return 0; 2738 } 2739 2740 /* we want to kick the TX after we've ack the up/down IRQs. */ 2741 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr) 2742 { 2743 queue_work(system_long_wq, &mgr->tx_work); 2744 } 2745 2746 static void drm_dp_mst_dump_mstb(struct seq_file *m, 2747 struct drm_dp_mst_branch *mstb) 2748 { 2749 struct drm_dp_mst_port *port; 2750 int tabs = mstb->lct; 2751 char prefix[10]; 2752 int i; 2753 2754 for (i = 0; i < tabs; i++) 2755 prefix[i] = '\t'; 2756 prefix[i] = '\0'; 2757 2758 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports); 2759 list_for_each_entry(port, &mstb->ports, next) { 2760 seq_printf(m, "%sport: %d: input: %d: pdt: %d, ddps: %d ldps: %d, sdp: %d/%d, %p, conn: %p\n", prefix, port->port_num, port->input, port->pdt, port->ddps, port->ldps, port->num_sdp_streams, port->num_sdp_stream_sinks, port, port->connector); 2761 if (port->mstb) 2762 drm_dp_mst_dump_mstb(m, port->mstb); 2763 } 2764 } 2765 2766 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr, 2767 char *buf) 2768 { 2769 int ret; 2770 int i; 2771 for (i = 0; i < 4; i++) { 2772 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16); 2773 if (ret != 16) 2774 break; 2775 } 2776 if (i == 4) 2777 return true; 2778 return false; 2779 } 2780 2781 static void fetch_monitor_name(struct drm_dp_mst_topology_mgr *mgr, 2782 struct drm_dp_mst_port *port, char *name, 2783 int namelen) 2784 { 2785 struct edid *mst_edid; 2786 2787 mst_edid = drm_dp_mst_get_edid(port->connector, mgr, port); 2788 drm_edid_get_monitor_name(mst_edid, name, namelen); 2789 } 2790 2791 /** 2792 * drm_dp_mst_dump_topology(): dump topology to seq file. 2793 * @m: seq_file to dump output to 2794 * @mgr: manager to dump current topology for. 2795 * 2796 * helper to dump MST topology to a seq file for debugfs. 2797 */ 2798 void drm_dp_mst_dump_topology(struct seq_file *m, 2799 struct drm_dp_mst_topology_mgr *mgr) 2800 { 2801 int i; 2802 struct drm_dp_mst_port *port; 2803 2804 mutex_lock(&mgr->lock); 2805 if (mgr->mst_primary) 2806 drm_dp_mst_dump_mstb(m, mgr->mst_primary); 2807 2808 /* dump VCPIs */ 2809 mutex_unlock(&mgr->lock); 2810 2811 mutex_lock(&mgr->payload_lock); 2812 seq_printf(m, "vcpi: %lx %lx %d\n", mgr->payload_mask, mgr->vcpi_mask, 2813 mgr->max_payloads); 2814 2815 for (i = 0; i < mgr->max_payloads; i++) { 2816 if (mgr->proposed_vcpis[i]) { 2817 char name[14]; 2818 2819 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi); 2820 fetch_monitor_name(mgr, port, name, sizeof(name)); 2821 seq_printf(m, "vcpi %d: %d %d %d sink name: %s\n", i, 2822 port->port_num, port->vcpi.vcpi, 2823 port->vcpi.num_slots, 2824 (*name != 0) ? name : "Unknown"); 2825 } else 2826 seq_printf(m, "vcpi %d:unused\n", i); 2827 } 2828 for (i = 0; i < mgr->max_payloads; i++) { 2829 seq_printf(m, "payload %d: %d, %d, %d\n", 2830 i, 2831 mgr->payloads[i].payload_state, 2832 mgr->payloads[i].start_slot, 2833 mgr->payloads[i].num_slots); 2834 2835 2836 } 2837 mutex_unlock(&mgr->payload_lock); 2838 2839 mutex_lock(&mgr->lock); 2840 if (mgr->mst_primary) { 2841 u8 buf[64]; 2842 bool bret; 2843 int ret; 2844 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE); 2845 seq_printf(m, "dpcd: "); 2846 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++) 2847 seq_printf(m, "%02x ", buf[i]); 2848 seq_printf(m, "\n"); 2849 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2); 2850 seq_printf(m, "faux/mst: "); 2851 for (i = 0; i < 2; i++) 2852 seq_printf(m, "%02x ", buf[i]); 2853 seq_printf(m, "\n"); 2854 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1); 2855 seq_printf(m, "mst ctrl: "); 2856 for (i = 0; i < 1; i++) 2857 seq_printf(m, "%02x ", buf[i]); 2858 seq_printf(m, "\n"); 2859 2860 /* dump the standard OUI branch header */ 2861 ret = drm_dp_dpcd_read(mgr->aux, DP_BRANCH_OUI, buf, DP_BRANCH_OUI_HEADER_SIZE); 2862 seq_printf(m, "branch oui: "); 2863 for (i = 0; i < 0x3; i++) 2864 seq_printf(m, "%02x", buf[i]); 2865 seq_printf(m, " devid: "); 2866 for (i = 0x3; i < 0x8 && buf[i]; i++) 2867 seq_printf(m, "%c", buf[i]); 2868 2869 seq_printf(m, " revision: hw: %x.%x sw: %x.%x", buf[0x9] >> 4, buf[0x9] & 0xf, buf[0xa], buf[0xb]); 2870 seq_printf(m, "\n"); 2871 bret = dump_dp_payload_table(mgr, buf); 2872 if (bret == true) { 2873 seq_printf(m, "payload table: "); 2874 for (i = 0; i < 63; i++) 2875 seq_printf(m, "%02x ", buf[i]); 2876 seq_printf(m, "\n"); 2877 } 2878 2879 } 2880 2881 mutex_unlock(&mgr->lock); 2882 2883 } 2884 EXPORT_SYMBOL(drm_dp_mst_dump_topology); 2885 2886 static void drm_dp_tx_work(struct work_struct *work) 2887 { 2888 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work); 2889 2890 mutex_lock(&mgr->qlock); 2891 if (mgr->tx_down_in_progress) 2892 process_single_down_tx_qlock(mgr); 2893 mutex_unlock(&mgr->qlock); 2894 } 2895 2896 static void drm_dp_free_mst_port(struct kref *kref) 2897 { 2898 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref); 2899 kref_put(&port->parent->kref, drm_dp_free_mst_branch_device); 2900 kfree(port); 2901 } 2902 2903 static void drm_dp_destroy_connector_work(struct work_struct *work) 2904 { 2905 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, destroy_connector_work); 2906 struct drm_dp_mst_port *port; 2907 bool send_hotplug = false; 2908 /* 2909 * Not a regular list traverse as we have to drop the destroy 2910 * connector lock before destroying the connector, to avoid AB->BA 2911 * ordering between this lock and the config mutex. 2912 */ 2913 for (;;) { 2914 mutex_lock(&mgr->destroy_connector_lock); 2915 port = list_first_entry_or_null(&mgr->destroy_connector_list, struct drm_dp_mst_port, next); 2916 if (!port) { 2917 mutex_unlock(&mgr->destroy_connector_lock); 2918 break; 2919 } 2920 list_del(&port->next); 2921 mutex_unlock(&mgr->destroy_connector_lock); 2922 2923 kref_init(&port->kref); 2924 INIT_LIST_HEAD(&port->next); 2925 2926 mgr->cbs->destroy_connector(mgr, port->connector); 2927 2928 drm_dp_port_teardown_pdt(port, port->pdt); 2929 2930 if (!port->input && port->vcpi.vcpi > 0) { 2931 drm_dp_mst_reset_vcpi_slots(mgr, port); 2932 drm_dp_update_payload_part1(mgr); 2933 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi); 2934 } 2935 2936 kref_put(&port->kref, drm_dp_free_mst_port); 2937 send_hotplug = true; 2938 } 2939 if (send_hotplug) 2940 (*mgr->cbs->hotplug)(mgr); 2941 } 2942 2943 /** 2944 * drm_dp_mst_topology_mgr_init - initialise a topology manager 2945 * @mgr: manager struct to initialise 2946 * @dev: device providing this structure - for i2c addition. 2947 * @aux: DP helper aux channel to talk to this device 2948 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit 2949 * @max_payloads: maximum number of payloads this GPU can source 2950 * @conn_base_id: the connector object ID the MST device is connected to. 2951 * 2952 * Return 0 for success, or negative error code on failure 2953 */ 2954 int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, 2955 struct device *dev, struct drm_dp_aux *aux, 2956 int max_dpcd_transaction_bytes, 2957 int max_payloads, int conn_base_id) 2958 { 2959 lockinit(&mgr->lock, "drmml", 0, LK_CANRECURSE); 2960 lockinit(&mgr->qlock, "drmmql", 0, LK_CANRECURSE); 2961 lockinit(&mgr->payload_lock, "drmmpl", 0, LK_CANRECURSE); 2962 lockinit(&mgr->destroy_connector_lock, "drmmdcl", 0, LK_CANRECURSE); 2963 INIT_LIST_HEAD(&mgr->tx_msg_downq); 2964 INIT_LIST_HEAD(&mgr->destroy_connector_list); 2965 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work); 2966 INIT_WORK(&mgr->tx_work, drm_dp_tx_work); 2967 INIT_WORK(&mgr->destroy_connector_work, drm_dp_destroy_connector_work); 2968 init_waitqueue_head(&mgr->tx_waitq); 2969 mgr->dev = dev; 2970 mgr->aux = aux; 2971 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes; 2972 mgr->max_payloads = max_payloads; 2973 mgr->conn_base_id = conn_base_id; 2974 if (max_payloads + 1 > sizeof(mgr->payload_mask) * 8 || 2975 max_payloads + 1 > sizeof(mgr->vcpi_mask) * 8) 2976 return -EINVAL; 2977 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL); 2978 if (!mgr->payloads) 2979 return -ENOMEM; 2980 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL); 2981 if (!mgr->proposed_vcpis) 2982 return -ENOMEM; 2983 set_bit(0, &mgr->payload_mask); 2984 if (test_calc_pbn_mode() < 0) 2985 DRM_ERROR("MST PBN self-test failed\n"); 2986 2987 return 0; 2988 } 2989 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init); 2990 2991 /** 2992 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager. 2993 * @mgr: manager to destroy 2994 */ 2995 void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr) 2996 { 2997 flush_work(&mgr->work); 2998 flush_work(&mgr->destroy_connector_work); 2999 mutex_lock(&mgr->payload_lock); 3000 kfree(mgr->payloads); 3001 mgr->payloads = NULL; 3002 kfree(mgr->proposed_vcpis); 3003 mgr->proposed_vcpis = NULL; 3004 mutex_unlock(&mgr->payload_lock); 3005 mgr->dev = NULL; 3006 mgr->aux = NULL; 3007 } 3008 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy); 3009 3010 /* I2C device */ 3011 static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, 3012 int num) 3013 { 3014 struct drm_dp_aux *aux = adapter->algo_data; 3015 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux); 3016 struct drm_dp_mst_branch *mstb; 3017 struct drm_dp_mst_topology_mgr *mgr = port->mgr; 3018 unsigned int i; 3019 bool reading = false; 3020 struct drm_dp_sideband_msg_req_body msg; 3021 struct drm_dp_sideband_msg_tx *txmsg = NULL; 3022 int ret; 3023 3024 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent); 3025 if (!mstb) 3026 return -EREMOTEIO; 3027 3028 /* construct i2c msg */ 3029 /* see if last msg is a read */ 3030 if (msgs[num - 1].flags & I2C_M_RD) 3031 reading = true; 3032 3033 if (!reading || (num - 1 > DP_REMOTE_I2C_READ_MAX_TRANSACTIONS)) { 3034 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n"); 3035 ret = -EIO; 3036 goto out; 3037 } 3038 3039 memset(&msg, 0, sizeof(msg)); 3040 msg.req_type = DP_REMOTE_I2C_READ; 3041 msg.u.i2c_read.num_transactions = num - 1; 3042 msg.u.i2c_read.port_number = port->port_num; 3043 for (i = 0; i < num - 1; i++) { 3044 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr; 3045 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len; 3046 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf; 3047 } 3048 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr; 3049 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len; 3050 3051 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 3052 if (!txmsg) { 3053 ret = -ENOMEM; 3054 goto out; 3055 } 3056 3057 txmsg->dst = mstb; 3058 drm_dp_encode_sideband_req(&msg, txmsg); 3059 3060 drm_dp_queue_down_tx(mgr, txmsg); 3061 3062 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 3063 if (ret > 0) { 3064 3065 if (txmsg->reply.reply_type == 1) { /* got a NAK back */ 3066 ret = -EREMOTEIO; 3067 goto out; 3068 } 3069 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) { 3070 ret = -EIO; 3071 goto out; 3072 } 3073 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len); 3074 ret = num; 3075 } 3076 out: 3077 kfree(txmsg); 3078 drm_dp_put_mst_branch_device(mstb); 3079 return ret; 3080 } 3081 3082 static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter) 3083 { 3084 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | 3085 I2C_FUNC_SMBUS_READ_BLOCK_DATA | 3086 I2C_FUNC_SMBUS_BLOCK_PROC_CALL | 3087 I2C_FUNC_10BIT_ADDR; 3088 } 3089 3090 static const struct i2c_algorithm drm_dp_mst_i2c_algo = { 3091 .functionality = drm_dp_mst_i2c_functionality, 3092 .master_xfer = drm_dp_mst_i2c_xfer, 3093 }; 3094 3095 /** 3096 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX 3097 * @aux: DisplayPort AUX channel 3098 * 3099 * Returns 0 on success or a negative error code on failure. 3100 */ 3101 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux) 3102 { 3103 aux->ddc.algo = &drm_dp_mst_i2c_algo; 3104 aux->ddc.algo_data = aux; 3105 aux->ddc.retries = 3; 3106 3107 #if 0 3108 aux->ddc.class = I2C_CLASS_DDC; 3109 aux->ddc.owner = THIS_MODULE; 3110 #endif 3111 aux->ddc.dev.parent = aux->dev; 3112 #if 0 3113 aux->ddc.dev.of_node = aux->dev->of_node; 3114 #endif 3115 3116 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev), 3117 sizeof(aux->ddc.name)); 3118 3119 return i2c_add_adapter(&aux->ddc); 3120 } 3121 3122 /** 3123 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter 3124 * @aux: DisplayPort AUX channel 3125 */ 3126 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux) 3127 { 3128 i2c_del_adapter(&aux->ddc); 3129 } 3130