1 // SPDX-License-Identifier: GPL-2.0-only 2 #include <linux/component.h> 3 #include <linux/export.h> 4 #include <linux/list.h> 5 #include <linux/media-bus-format.h> 6 #include <linux/of.h> 7 #include <linux/of_graph.h> 8 9 #include <drm/drm_bridge.h> 10 #include <drm/drm_connector.h> 11 #include <drm/drm_crtc.h> 12 #include <drm/drm_device.h> 13 #include <drm/drm_encoder.h> 14 #include <drm/drm_mipi_dsi.h> 15 #include <drm/drm_of.h> 16 #include <drm/drm_panel.h> 17 18 /** 19 * DOC: overview 20 * 21 * A set of helper functions to aid DRM drivers in parsing standard DT 22 * properties. 23 */ 24 25 /** 26 * drm_of_crtc_port_mask - find the mask of a registered CRTC by port OF node 27 * @dev: DRM device 28 * @port: port OF node 29 * 30 * Given a port OF node, return the possible mask of the corresponding 31 * CRTC within a device's list of CRTCs. Returns zero if not found. 32 */ 33 uint32_t drm_of_crtc_port_mask(struct drm_device *dev, 34 struct device_node *port) 35 { 36 unsigned int index = 0; 37 struct drm_crtc *tmp; 38 39 drm_for_each_crtc(tmp, dev) { 40 if (tmp->port == port) 41 return 1 << index; 42 43 index++; 44 } 45 46 return 0; 47 } 48 EXPORT_SYMBOL(drm_of_crtc_port_mask); 49 50 /** 51 * drm_of_find_possible_crtcs - find the possible CRTCs for an encoder port 52 * @dev: DRM device 53 * @port: encoder port to scan for endpoints 54 * 55 * Scan all endpoints attached to a port, locate their attached CRTCs, 56 * and generate the DRM mask of CRTCs which may be attached to this 57 * encoder. 58 * 59 * See https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/graph.yaml 60 * for the bindings. 61 */ 62 uint32_t drm_of_find_possible_crtcs(struct drm_device *dev, 63 struct device_node *port) 64 { 65 struct device_node *remote_port, *ep; 66 uint32_t possible_crtcs = 0; 67 68 for_each_endpoint_of_node(port, ep) { 69 remote_port = of_graph_get_remote_port(ep); 70 if (!remote_port) { 71 of_node_put(ep); 72 return 0; 73 } 74 75 possible_crtcs |= drm_of_crtc_port_mask(dev, remote_port); 76 77 of_node_put(remote_port); 78 } 79 80 return possible_crtcs; 81 } 82 EXPORT_SYMBOL(drm_of_find_possible_crtcs); 83 84 /** 85 * drm_of_component_match_add - Add a component helper OF node match rule 86 * @master: master device 87 * @matchptr: component match pointer 88 * @compare: compare function used for matching component 89 * @node: of_node 90 */ 91 void drm_of_component_match_add(struct device *master, 92 struct component_match **matchptr, 93 int (*compare)(struct device *, void *), 94 struct device_node *node) 95 { 96 of_node_get(node); 97 component_match_add_release(master, matchptr, component_release_of, 98 compare, node); 99 } 100 EXPORT_SYMBOL_GPL(drm_of_component_match_add); 101 102 /** 103 * drm_of_component_probe - Generic probe function for a component based master 104 * @dev: master device containing the OF node 105 * @compare_of: compare function used for matching components 106 * @m_ops: component master ops to be used 107 * 108 * Parse the platform device OF node and bind all the components associated 109 * with the master. Interface ports are added before the encoders in order to 110 * satisfy their .bind requirements 111 * 112 * See https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/graph.yaml 113 * for the bindings. 114 * 115 * Returns zero if successful, or one of the standard error codes if it fails. 116 */ 117 int drm_of_component_probe(struct device *dev, 118 int (*compare_of)(struct device *, void *), 119 const struct component_master_ops *m_ops) 120 { 121 struct device_node *ep, *port, *remote; 122 struct component_match *match = NULL; 123 int i; 124 125 if (!dev->of_node) 126 return -EINVAL; 127 128 /* 129 * Bind the crtc's ports first, so that drm_of_find_possible_crtcs() 130 * called from encoder's .bind callbacks works as expected 131 */ 132 for (i = 0; ; i++) { 133 port = of_parse_phandle(dev->of_node, "ports", i); 134 if (!port) 135 break; 136 137 if (of_device_is_available(port->parent)) 138 drm_of_component_match_add(dev, &match, compare_of, 139 port); 140 141 of_node_put(port); 142 } 143 144 if (i == 0) { 145 dev_err(dev, "missing 'ports' property\n"); 146 return -ENODEV; 147 } 148 149 if (!match) { 150 dev_err(dev, "no available port\n"); 151 return -ENODEV; 152 } 153 154 /* 155 * For bound crtcs, bind the encoders attached to their remote endpoint 156 */ 157 for (i = 0; ; i++) { 158 port = of_parse_phandle(dev->of_node, "ports", i); 159 if (!port) 160 break; 161 162 if (!of_device_is_available(port->parent)) { 163 of_node_put(port); 164 continue; 165 } 166 167 for_each_child_of_node(port, ep) { 168 remote = of_graph_get_remote_port_parent(ep); 169 if (!remote || !of_device_is_available(remote)) { 170 of_node_put(remote); 171 continue; 172 } else if (!of_device_is_available(remote->parent)) { 173 dev_warn(dev, "parent device of %pOF is not available\n", 174 remote); 175 of_node_put(remote); 176 continue; 177 } 178 179 drm_of_component_match_add(dev, &match, compare_of, 180 remote); 181 of_node_put(remote); 182 } 183 of_node_put(port); 184 } 185 186 return component_master_add_with_match(dev, m_ops, match); 187 } 188 EXPORT_SYMBOL(drm_of_component_probe); 189 190 /* 191 * drm_of_encoder_active_endpoint - return the active encoder endpoint 192 * @node: device tree node containing encoder input ports 193 * @encoder: drm_encoder 194 * 195 * Given an encoder device node and a drm_encoder with a connected crtc, 196 * parse the encoder endpoint connecting to the crtc port. 197 */ 198 int drm_of_encoder_active_endpoint(struct device_node *node, 199 struct drm_encoder *encoder, 200 struct of_endpoint *endpoint) 201 { 202 struct device_node *ep; 203 struct drm_crtc *crtc = encoder->crtc; 204 struct device_node *port; 205 int ret; 206 207 if (!node || !crtc) 208 return -EINVAL; 209 210 for_each_endpoint_of_node(node, ep) { 211 port = of_graph_get_remote_port(ep); 212 of_node_put(port); 213 if (port == crtc->port) { 214 ret = of_graph_parse_endpoint(ep, endpoint); 215 of_node_put(ep); 216 return ret; 217 } 218 } 219 220 return -EINVAL; 221 } 222 EXPORT_SYMBOL_GPL(drm_of_encoder_active_endpoint); 223 224 /** 225 * drm_of_get_panel_orientation - look up the orientation of the panel through 226 * the "rotation" binding from a device tree node 227 * @np: device tree node of the panel 228 * @orientation: orientation enum to be filled in 229 * 230 * Looks up the rotation of a panel in the device tree. The orientation of the 231 * panel is expressed as a property name "rotation" in the device tree. The 232 * rotation in the device tree is counter clockwise. 233 * 234 * Return: 0 when a valid rotation value (0, 90, 180, or 270) is read or the 235 * rotation property doesn't exist. Return a negative error code on failure. 236 */ 237 int drm_of_get_panel_orientation(const struct device_node *np, 238 enum drm_panel_orientation *orientation) 239 { 240 int rotation, ret; 241 242 ret = of_property_read_u32(np, "rotation", &rotation); 243 if (ret == -EINVAL) { 244 /* Don't return an error if there's no rotation property. */ 245 *orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN; 246 return 0; 247 } 248 249 if (ret < 0) 250 return ret; 251 252 if (rotation == 0) 253 *orientation = DRM_MODE_PANEL_ORIENTATION_NORMAL; 254 else if (rotation == 90) 255 *orientation = DRM_MODE_PANEL_ORIENTATION_RIGHT_UP; 256 else if (rotation == 180) 257 *orientation = DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP; 258 else if (rotation == 270) 259 *orientation = DRM_MODE_PANEL_ORIENTATION_LEFT_UP; 260 else 261 return -EINVAL; 262 263 return 0; 264 } 265 EXPORT_SYMBOL_GPL(drm_of_get_panel_orientation); 266 267 enum drm_of_lvds_pixels { 268 DRM_OF_LVDS_EVEN = BIT(0), 269 DRM_OF_LVDS_ODD = BIT(1), 270 }; 271 272 static int drm_of_lvds_get_port_pixels_type(struct device_node *port_node) 273 { 274 bool even_pixels = 275 of_property_read_bool(port_node, "dual-lvds-even-pixels"); 276 bool odd_pixels = 277 of_property_read_bool(port_node, "dual-lvds-odd-pixels"); 278 279 return (even_pixels ? DRM_OF_LVDS_EVEN : 0) | 280 (odd_pixels ? DRM_OF_LVDS_ODD : 0); 281 } 282 283 static int drm_of_lvds_get_remote_pixels_type( 284 const struct device_node *port_node) 285 { 286 struct device_node *endpoint = NULL; 287 int pixels_type = -EPIPE; 288 289 for_each_child_of_node(port_node, endpoint) { 290 struct device_node *remote_port; 291 int current_pt; 292 293 if (!of_node_name_eq(endpoint, "endpoint")) 294 continue; 295 296 remote_port = of_graph_get_remote_port(endpoint); 297 if (!remote_port) { 298 of_node_put(endpoint); 299 return -EPIPE; 300 } 301 302 current_pt = drm_of_lvds_get_port_pixels_type(remote_port); 303 of_node_put(remote_port); 304 if (pixels_type < 0) 305 pixels_type = current_pt; 306 307 /* 308 * Sanity check, ensure that all remote endpoints have the same 309 * pixel type. We may lift this restriction later if we need to 310 * support multiple sinks with different dual-link 311 * configurations by passing the endpoints explicitly to 312 * drm_of_lvds_get_dual_link_pixel_order(). 313 */ 314 if (!current_pt || pixels_type != current_pt) { 315 of_node_put(endpoint); 316 return -EINVAL; 317 } 318 } 319 320 return pixels_type; 321 } 322 323 static int __drm_of_lvds_get_dual_link_pixel_order(int p1_pt, int p2_pt) 324 { 325 /* 326 * A valid dual-lVDS bus is found when one port is marked with 327 * "dual-lvds-even-pixels", and the other port is marked with 328 * "dual-lvds-odd-pixels", bail out if the markers are not right. 329 */ 330 if (p1_pt + p2_pt != DRM_OF_LVDS_EVEN + DRM_OF_LVDS_ODD) 331 return -EINVAL; 332 333 return p1_pt == DRM_OF_LVDS_EVEN ? 334 DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS : 335 DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS; 336 } 337 338 /** 339 * drm_of_lvds_get_dual_link_pixel_order - Get LVDS dual-link source pixel order 340 * @port1: First DT port node of the Dual-link LVDS source 341 * @port2: Second DT port node of the Dual-link LVDS source 342 * 343 * An LVDS dual-link connection is made of two links, with even pixels 344 * transitting on one link, and odd pixels on the other link. This function 345 * returns, for two ports of an LVDS dual-link source, which port shall transmit 346 * the even and odd pixels, based on the requirements of the connected sink. 347 * 348 * The pixel order is determined from the dual-lvds-even-pixels and 349 * dual-lvds-odd-pixels properties in the sink's DT port nodes. If those 350 * properties are not present, or if their usage is not valid, this function 351 * returns -EINVAL. 352 * 353 * If either port is not connected, this function returns -EPIPE. 354 * 355 * @port1 and @port2 are typically DT sibling nodes, but may have different 356 * parents when, for instance, two separate LVDS encoders carry the even and odd 357 * pixels. 358 * 359 * Return: 360 * * DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS - @port1 carries even pixels and @port2 361 * carries odd pixels 362 * * DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS - @port1 carries odd pixels and @port2 363 * carries even pixels 364 * * -EINVAL - @port1 and @port2 are not connected to a dual-link LVDS sink, or 365 * the sink configuration is invalid 366 * * -EPIPE - when @port1 or @port2 are not connected 367 */ 368 int drm_of_lvds_get_dual_link_pixel_order(const struct device_node *port1, 369 const struct device_node *port2) 370 { 371 int remote_p1_pt, remote_p2_pt; 372 373 if (!port1 || !port2) 374 return -EINVAL; 375 376 remote_p1_pt = drm_of_lvds_get_remote_pixels_type(port1); 377 if (remote_p1_pt < 0) 378 return remote_p1_pt; 379 380 remote_p2_pt = drm_of_lvds_get_remote_pixels_type(port2); 381 if (remote_p2_pt < 0) 382 return remote_p2_pt; 383 384 return __drm_of_lvds_get_dual_link_pixel_order(remote_p1_pt, remote_p2_pt); 385 } 386 EXPORT_SYMBOL_GPL(drm_of_lvds_get_dual_link_pixel_order); 387 388 /** 389 * drm_of_lvds_get_dual_link_pixel_order_sink - Get LVDS dual-link sink pixel order 390 * @port1: First DT port node of the Dual-link LVDS sink 391 * @port2: Second DT port node of the Dual-link LVDS sink 392 * 393 * An LVDS dual-link connection is made of two links, with even pixels 394 * transitting on one link, and odd pixels on the other link. This function 395 * returns, for two ports of an LVDS dual-link sink, which port shall transmit 396 * the even and odd pixels, based on the requirements of the sink. 397 * 398 * The pixel order is determined from the dual-lvds-even-pixels and 399 * dual-lvds-odd-pixels properties in the sink's DT port nodes. If those 400 * properties are not present, or if their usage is not valid, this function 401 * returns -EINVAL. 402 * 403 * If either port is not connected, this function returns -EPIPE. 404 * 405 * @port1 and @port2 are typically DT sibling nodes, but may have different 406 * parents when, for instance, two separate LVDS decoders receive the even and 407 * odd pixels. 408 * 409 * Return: 410 * * DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS - @port1 receives even pixels and @port2 411 * receives odd pixels 412 * * DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS - @port1 receives odd pixels and @port2 413 * receives even pixels 414 * * -EINVAL - @port1 or @port2 are NULL 415 * * -EPIPE - when @port1 or @port2 are not connected 416 */ 417 int drm_of_lvds_get_dual_link_pixel_order_sink(struct device_node *port1, 418 struct device_node *port2) 419 { 420 int sink_p1_pt, sink_p2_pt; 421 422 if (!port1 || !port2) 423 return -EINVAL; 424 425 sink_p1_pt = drm_of_lvds_get_port_pixels_type(port1); 426 if (!sink_p1_pt) 427 return -EPIPE; 428 429 sink_p2_pt = drm_of_lvds_get_port_pixels_type(port2); 430 if (!sink_p2_pt) 431 return -EPIPE; 432 433 return __drm_of_lvds_get_dual_link_pixel_order(sink_p1_pt, sink_p2_pt); 434 } 435 EXPORT_SYMBOL_GPL(drm_of_lvds_get_dual_link_pixel_order_sink); 436 437 /** 438 * drm_of_lvds_get_data_mapping - Get LVDS data mapping 439 * @port: DT port node of the LVDS source or sink 440 * 441 * Convert DT "data-mapping" property string value into media bus format value. 442 * 443 * Return: 444 * * MEDIA_BUS_FMT_RGB666_1X7X3_SPWG - data-mapping is "jeida-18" 445 * * MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA - data-mapping is "jeida-24" 446 * * MEDIA_BUS_FMT_RGB101010_1X7X5_JEIDA - data-mapping is "jeida-30" 447 * * MEDIA_BUS_FMT_RGB888_1X7X4_SPWG - data-mapping is "vesa-24" 448 * * MEDIA_BUS_FMT_RGB101010_1X7X5_SPWG - data-mapping is "vesa-30" 449 * * -EINVAL - the "data-mapping" property is unsupported 450 * * -ENODEV - the "data-mapping" property is missing 451 */ 452 int drm_of_lvds_get_data_mapping(const struct device_node *port) 453 { 454 const char *mapping; 455 int ret; 456 457 ret = of_property_read_string(port, "data-mapping", &mapping); 458 if (ret < 0) 459 return -ENODEV; 460 461 if (!strcmp(mapping, "jeida-18")) 462 return MEDIA_BUS_FMT_RGB666_1X7X3_SPWG; 463 if (!strcmp(mapping, "jeida-24")) 464 return MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA; 465 if (!strcmp(mapping, "jeida-30")) 466 return MEDIA_BUS_FMT_RGB101010_1X7X5_JEIDA; 467 if (!strcmp(mapping, "vesa-24")) 468 return MEDIA_BUS_FMT_RGB888_1X7X4_SPWG; 469 if (!strcmp(mapping, "vesa-30")) 470 return MEDIA_BUS_FMT_RGB101010_1X7X5_SPWG; 471 472 return -EINVAL; 473 } 474 EXPORT_SYMBOL_GPL(drm_of_lvds_get_data_mapping); 475 476 /** 477 * drm_of_get_data_lanes_count - Get DSI/(e)DP data lane count 478 * @endpoint: DT endpoint node of the DSI/(e)DP source or sink 479 * @min: minimum supported number of data lanes 480 * @max: maximum supported number of data lanes 481 * 482 * Count DT "data-lanes" property elements and check for validity. 483 * 484 * Return: 485 * * min..max - positive integer count of "data-lanes" elements 486 * * -ENODATA - the property does not have a value. 487 * * -EINVAL - the "data-lanes" property is missing or invalid 488 */ 489 int drm_of_get_data_lanes_count(const struct device_node *endpoint, 490 const unsigned int min, const unsigned int max) 491 { 492 int ret; 493 494 ret = of_property_count_u32_elems(endpoint, "data-lanes"); 495 if (ret < 0) 496 return ret; 497 498 if (ret < min || ret > max) 499 return -EINVAL; 500 501 return ret; 502 } 503 EXPORT_SYMBOL_GPL(drm_of_get_data_lanes_count); 504 505 /** 506 * drm_of_get_data_lanes_count_ep - Get DSI/(e)DP data lane count by endpoint 507 * @port: DT port node of the DSI/(e)DP source or sink 508 * @port_reg: identifier (value of reg property) of the parent port node 509 * @reg: identifier (value of reg property) of the endpoint node 510 * @min: minimum supported number of data lanes 511 * @max: maximum supported number of data lanes 512 * 513 * Count DT "data-lanes" property elements and check for validity. 514 * This variant uses endpoint specifier. 515 * 516 * Return: 517 * * min..max - positive integer count of "data-lanes" elements 518 * * -ENODATA - the property does not have a value. 519 * * -EINVAL - the "data-lanes" property is missing or invalid 520 */ 521 int drm_of_get_data_lanes_count_ep(const struct device_node *port, 522 int port_reg, int reg, 523 const unsigned int min, 524 const unsigned int max) 525 { 526 struct device_node *endpoint; 527 int ret; 528 529 endpoint = of_graph_get_endpoint_by_regs(port, port_reg, reg); 530 ret = drm_of_get_data_lanes_count(endpoint, min, max); 531 of_node_put(endpoint); 532 533 return ret; 534 } 535 EXPORT_SYMBOL_GPL(drm_of_get_data_lanes_count_ep); 536 537 /** 538 * drm_of_get_data_lanes_count_remote - Get DSI/(e)DP data lane count by endpoint 539 * @port: DT port node of the DSI/(e)DP source or sink 540 * @port_reg: identifier (value of reg property) of the parent port node 541 * @reg: identifier (value of reg property) of the endpoint node 542 * @min: minimum supported number of data lanes 543 * @max: maximum supported number of data lanes 544 * 545 * Count DT "data-lanes" property elements in the remote endpoint and check for 546 * validity. This variant uses endpoint specifier. 547 * 548 * Return: 549 * * min..max - positive integer count of "data-lanes" elements 550 * * -EINVAL - the "data-lanes" property is unsupported 551 * * -ENODEV - the "data-lanes" property is missing 552 */ 553 int drm_of_get_data_lanes_count_remote(const struct device_node *port, 554 int port_reg, int reg, 555 const unsigned int min, 556 const unsigned int max) 557 { 558 struct device_node *endpoint, *remote; 559 int ret; 560 561 endpoint = of_graph_get_endpoint_by_regs(port, port_reg, reg); 562 remote = of_graph_get_remote_endpoint(endpoint); 563 of_node_put(endpoint); 564 ret = drm_of_get_data_lanes_count(remote, min, max); 565 of_node_put(remote); 566 567 return ret; 568 } 569 EXPORT_SYMBOL_GPL(drm_of_get_data_lanes_count_remote); 570 571 #if IS_ENABLED(CONFIG_DRM_MIPI_DSI) 572 573 /** 574 * drm_of_get_dsi_bus - find the DSI bus for a given device 575 * @dev: parent device of display (SPI, I2C) 576 * 577 * Gets parent DSI bus for a DSI device controlled through a bus other 578 * than MIPI-DCS (SPI, I2C, etc.) using the Device Tree. 579 * 580 * This function assumes that the device's port@0 is the DSI input. 581 * 582 * Returns pointer to mipi_dsi_host if successful, -EINVAL if the 583 * request is unsupported, -EPROBE_DEFER if the DSI host is found but 584 * not available, or -ENODEV otherwise. 585 */ 586 struct mipi_dsi_host *drm_of_get_dsi_bus(struct device *dev) 587 { 588 struct mipi_dsi_host *dsi_host; 589 struct device_node *endpoint, *dsi_host_node; 590 591 /* 592 * Get first endpoint child from device. 593 */ 594 endpoint = of_graph_get_endpoint_by_regs(dev->of_node, 0, -1); 595 if (!endpoint) 596 return ERR_PTR(-ENODEV); 597 598 /* 599 * Follow the first endpoint to get the DSI host node and then 600 * release the endpoint since we no longer need it. 601 */ 602 dsi_host_node = of_graph_get_remote_port_parent(endpoint); 603 of_node_put(endpoint); 604 if (!dsi_host_node) 605 return ERR_PTR(-ENODEV); 606 607 /* 608 * Get the DSI host from the DSI host node. If we get an error 609 * or the return is null assume we're not ready to probe just 610 * yet. Release the DSI host node since we're done with it. 611 */ 612 dsi_host = of_find_mipi_dsi_host_by_node(dsi_host_node); 613 of_node_put(dsi_host_node); 614 if (IS_ERR_OR_NULL(dsi_host)) 615 return ERR_PTR(-EPROBE_DEFER); 616 617 return dsi_host; 618 } 619 EXPORT_SYMBOL_GPL(drm_of_get_dsi_bus); 620 621 #endif /* CONFIG_DRM_MIPI_DSI */ 622