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