1 /* 2 * Copyright © 2008 Keith Packard 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 #ifndef _DRM_DP_HELPER_H_ 24 #define _DRM_DP_HELPER_H_ 25 26 #include <linux/types.h> 27 #include <linux/i2c.h> 28 #include <linux/delay.h> 29 30 /* 31 * Unless otherwise noted, all values are from the DP 1.1a spec. Note that 32 * DP and DPCD versions are independent. Differences from 1.0 are not noted, 33 * 1.0 devices basically don't exist in the wild. 34 * 35 * Abbreviations, in chronological order: 36 * 37 * eDP: Embedded DisplayPort version 1 38 * DPI: DisplayPort Interoperability Guideline v1.1a 39 * 1.2: DisplayPort 1.2 40 * 41 * 1.2 formally includes both eDP and DPI definitions. 42 */ 43 44 #define DP_AUX_I2C_WRITE 0x0 45 #define DP_AUX_I2C_READ 0x1 46 #define DP_AUX_I2C_STATUS 0x2 47 #define DP_AUX_I2C_MOT 0x4 48 #define DP_AUX_NATIVE_WRITE 0x8 49 #define DP_AUX_NATIVE_READ 0x9 50 51 #define DP_AUX_NATIVE_REPLY_ACK (0x0 << 0) 52 #define DP_AUX_NATIVE_REPLY_NACK (0x1 << 0) 53 #define DP_AUX_NATIVE_REPLY_DEFER (0x2 << 0) 54 #define DP_AUX_NATIVE_REPLY_MASK (0x3 << 0) 55 56 #define DP_AUX_I2C_REPLY_ACK (0x0 << 2) 57 #define DP_AUX_I2C_REPLY_NACK (0x1 << 2) 58 #define DP_AUX_I2C_REPLY_DEFER (0x2 << 2) 59 #define DP_AUX_I2C_REPLY_MASK (0x3 << 2) 60 61 /* AUX CH addresses */ 62 /* DPCD */ 63 #define DP_DPCD_REV 0x000 64 65 #define DP_MAX_LINK_RATE 0x001 66 67 #define DP_MAX_LANE_COUNT 0x002 68 # define DP_MAX_LANE_COUNT_MASK 0x1f 69 # define DP_TPS3_SUPPORTED (1 << 6) /* 1.2 */ 70 # define DP_ENHANCED_FRAME_CAP (1 << 7) 71 72 #define DP_MAX_DOWNSPREAD 0x003 73 # define DP_NO_AUX_HANDSHAKE_LINK_TRAINING (1 << 6) 74 75 #define DP_NORP 0x004 76 77 #define DP_DOWNSTREAMPORT_PRESENT 0x005 78 # define DP_DWN_STRM_PORT_PRESENT (1 << 0) 79 # define DP_DWN_STRM_PORT_TYPE_MASK 0x06 80 # define DP_DWN_STRM_PORT_TYPE_DP (0 << 1) 81 # define DP_DWN_STRM_PORT_TYPE_ANALOG (1 << 1) 82 # define DP_DWN_STRM_PORT_TYPE_TMDS (2 << 1) 83 # define DP_DWN_STRM_PORT_TYPE_OTHER (3 << 1) 84 # define DP_FORMAT_CONVERSION (1 << 3) 85 # define DP_DETAILED_CAP_INFO_AVAILABLE (1 << 4) /* DPI */ 86 87 #define DP_MAIN_LINK_CHANNEL_CODING 0x006 88 89 #define DP_DOWN_STREAM_PORT_COUNT 0x007 90 # define DP_PORT_COUNT_MASK 0x0f 91 # define DP_MSA_TIMING_PAR_IGNORED (1 << 6) /* eDP */ 92 # define DP_OUI_SUPPORT (1 << 7) 93 94 #define DP_I2C_SPEED_CAP 0x00c /* DPI */ 95 # define DP_I2C_SPEED_1K 0x01 96 # define DP_I2C_SPEED_5K 0x02 97 # define DP_I2C_SPEED_10K 0x04 98 # define DP_I2C_SPEED_100K 0x08 99 # define DP_I2C_SPEED_400K 0x10 100 # define DP_I2C_SPEED_1M 0x20 101 102 #define DP_EDP_CONFIGURATION_CAP 0x00d /* XXX 1.2? */ 103 #define DP_TRAINING_AUX_RD_INTERVAL 0x00e /* XXX 1.2? */ 104 105 /* Multiple stream transport */ 106 #define DP_MSTM_CAP 0x021 /* 1.2 */ 107 # define DP_MST_CAP (1 << 0) 108 109 #define DP_PSR_SUPPORT 0x070 /* XXX 1.2? */ 110 # define DP_PSR_IS_SUPPORTED 1 111 #define DP_PSR_CAPS 0x071 /* XXX 1.2? */ 112 # define DP_PSR_NO_TRAIN_ON_EXIT 1 113 # define DP_PSR_SETUP_TIME_330 (0 << 1) 114 # define DP_PSR_SETUP_TIME_275 (1 << 1) 115 # define DP_PSR_SETUP_TIME_220 (2 << 1) 116 # define DP_PSR_SETUP_TIME_165 (3 << 1) 117 # define DP_PSR_SETUP_TIME_110 (4 << 1) 118 # define DP_PSR_SETUP_TIME_55 (5 << 1) 119 # define DP_PSR_SETUP_TIME_0 (6 << 1) 120 # define DP_PSR_SETUP_TIME_MASK (7 << 1) 121 # define DP_PSR_SETUP_TIME_SHIFT 1 122 123 /* 124 * 0x80-0x8f describe downstream port capabilities, but there are two layouts 125 * based on whether DP_DETAILED_CAP_INFO_AVAILABLE was set. If it was not, 126 * each port's descriptor is one byte wide. If it was set, each port's is 127 * four bytes wide, starting with the one byte from the base info. As of 128 * DP interop v1.1a only VGA defines additional detail. 129 */ 130 131 /* offset 0 */ 132 #define DP_DOWNSTREAM_PORT_0 0x80 133 # define DP_DS_PORT_TYPE_MASK (7 << 0) 134 # define DP_DS_PORT_TYPE_DP 0 135 # define DP_DS_PORT_TYPE_VGA 1 136 # define DP_DS_PORT_TYPE_DVI 2 137 # define DP_DS_PORT_TYPE_HDMI 3 138 # define DP_DS_PORT_TYPE_NON_EDID 4 139 # define DP_DS_PORT_HPD (1 << 3) 140 /* offset 1 for VGA is maximum megapixels per second / 8 */ 141 /* offset 2 */ 142 # define DP_DS_VGA_MAX_BPC_MASK (3 << 0) 143 # define DP_DS_VGA_8BPC 0 144 # define DP_DS_VGA_10BPC 1 145 # define DP_DS_VGA_12BPC 2 146 # define DP_DS_VGA_16BPC 3 147 148 /* link configuration */ 149 #define DP_LINK_BW_SET 0x100 150 # define DP_LINK_BW_1_62 0x06 151 # define DP_LINK_BW_2_7 0x0a 152 # define DP_LINK_BW_5_4 0x14 /* 1.2 */ 153 154 #define DP_LANE_COUNT_SET 0x101 155 # define DP_LANE_COUNT_MASK 0x0f 156 # define DP_LANE_COUNT_ENHANCED_FRAME_EN (1 << 7) 157 158 #define DP_TRAINING_PATTERN_SET 0x102 159 # define DP_TRAINING_PATTERN_DISABLE 0 160 # define DP_TRAINING_PATTERN_1 1 161 # define DP_TRAINING_PATTERN_2 2 162 # define DP_TRAINING_PATTERN_3 3 /* 1.2 */ 163 # define DP_TRAINING_PATTERN_MASK 0x3 164 165 # define DP_LINK_QUAL_PATTERN_DISABLE (0 << 2) 166 # define DP_LINK_QUAL_PATTERN_D10_2 (1 << 2) 167 # define DP_LINK_QUAL_PATTERN_ERROR_RATE (2 << 2) 168 # define DP_LINK_QUAL_PATTERN_PRBS7 (3 << 2) 169 # define DP_LINK_QUAL_PATTERN_MASK (3 << 2) 170 171 # define DP_RECOVERED_CLOCK_OUT_EN (1 << 4) 172 # define DP_LINK_SCRAMBLING_DISABLE (1 << 5) 173 174 # define DP_SYMBOL_ERROR_COUNT_BOTH (0 << 6) 175 # define DP_SYMBOL_ERROR_COUNT_DISPARITY (1 << 6) 176 # define DP_SYMBOL_ERROR_COUNT_SYMBOL (2 << 6) 177 # define DP_SYMBOL_ERROR_COUNT_MASK (3 << 6) 178 179 #define DP_TRAINING_LANE0_SET 0x103 180 #define DP_TRAINING_LANE1_SET 0x104 181 #define DP_TRAINING_LANE2_SET 0x105 182 #define DP_TRAINING_LANE3_SET 0x106 183 184 # define DP_TRAIN_VOLTAGE_SWING_MASK 0x3 185 # define DP_TRAIN_VOLTAGE_SWING_SHIFT 0 186 # define DP_TRAIN_MAX_SWING_REACHED (1 << 2) 187 # define DP_TRAIN_VOLTAGE_SWING_400 (0 << 0) 188 # define DP_TRAIN_VOLTAGE_SWING_600 (1 << 0) 189 # define DP_TRAIN_VOLTAGE_SWING_800 (2 << 0) 190 # define DP_TRAIN_VOLTAGE_SWING_1200 (3 << 0) 191 192 # define DP_TRAIN_PRE_EMPHASIS_MASK (3 << 3) 193 # define DP_TRAIN_PRE_EMPHASIS_0 (0 << 3) 194 # define DP_TRAIN_PRE_EMPHASIS_3_5 (1 << 3) 195 # define DP_TRAIN_PRE_EMPHASIS_6 (2 << 3) 196 # define DP_TRAIN_PRE_EMPHASIS_9_5 (3 << 3) 197 198 # define DP_TRAIN_PRE_EMPHASIS_SHIFT 3 199 # define DP_TRAIN_MAX_PRE_EMPHASIS_REACHED (1 << 5) 200 201 #define DP_DOWNSPREAD_CTRL 0x107 202 # define DP_SPREAD_AMP_0_5 (1 << 4) 203 # define DP_MSA_TIMING_PAR_IGNORE_EN (1 << 7) /* eDP */ 204 205 #define DP_MAIN_LINK_CHANNEL_CODING_SET 0x108 206 # define DP_SET_ANSI_8B10B (1 << 0) 207 208 #define DP_I2C_SPEED_CONTROL_STATUS 0x109 /* DPI */ 209 /* bitmask as for DP_I2C_SPEED_CAP */ 210 211 #define DP_EDP_CONFIGURATION_SET 0x10a /* XXX 1.2? */ 212 213 #define DP_MSTM_CTRL 0x111 /* 1.2 */ 214 # define DP_MST_EN (1 << 0) 215 # define DP_UP_REQ_EN (1 << 1) 216 # define DP_UPSTREAM_IS_SRC (1 << 2) 217 218 #define DP_PSR_EN_CFG 0x170 /* XXX 1.2? */ 219 # define DP_PSR_ENABLE (1 << 0) 220 # define DP_PSR_MAIN_LINK_ACTIVE (1 << 1) 221 # define DP_PSR_CRC_VERIFICATION (1 << 2) 222 # define DP_PSR_FRAME_CAPTURE (1 << 3) 223 224 #define DP_SINK_COUNT 0x200 225 /* prior to 1.2 bit 7 was reserved mbz */ 226 # define DP_GET_SINK_COUNT(x) ((((x) & 0x80) >> 1) | ((x) & 0x3f)) 227 # define DP_SINK_CP_READY (1 << 6) 228 229 #define DP_DEVICE_SERVICE_IRQ_VECTOR 0x201 230 # define DP_REMOTE_CONTROL_COMMAND_PENDING (1 << 0) 231 # define DP_AUTOMATED_TEST_REQUEST (1 << 1) 232 # define DP_CP_IRQ (1 << 2) 233 # define DP_SINK_SPECIFIC_IRQ (1 << 6) 234 235 #define DP_LANE0_1_STATUS 0x202 236 #define DP_LANE2_3_STATUS 0x203 237 # define DP_LANE_CR_DONE (1 << 0) 238 # define DP_LANE_CHANNEL_EQ_DONE (1 << 1) 239 # define DP_LANE_SYMBOL_LOCKED (1 << 2) 240 241 #define DP_CHANNEL_EQ_BITS (DP_LANE_CR_DONE | \ 242 DP_LANE_CHANNEL_EQ_DONE | \ 243 DP_LANE_SYMBOL_LOCKED) 244 245 #define DP_LANE_ALIGN_STATUS_UPDATED 0x204 246 247 #define DP_INTERLANE_ALIGN_DONE (1 << 0) 248 #define DP_DOWNSTREAM_PORT_STATUS_CHANGED (1 << 6) 249 #define DP_LINK_STATUS_UPDATED (1 << 7) 250 251 #define DP_SINK_STATUS 0x205 252 253 #define DP_RECEIVE_PORT_0_STATUS (1 << 0) 254 #define DP_RECEIVE_PORT_1_STATUS (1 << 1) 255 256 #define DP_ADJUST_REQUEST_LANE0_1 0x206 257 #define DP_ADJUST_REQUEST_LANE2_3 0x207 258 # define DP_ADJUST_VOLTAGE_SWING_LANE0_MASK 0x03 259 # define DP_ADJUST_VOLTAGE_SWING_LANE0_SHIFT 0 260 # define DP_ADJUST_PRE_EMPHASIS_LANE0_MASK 0x0c 261 # define DP_ADJUST_PRE_EMPHASIS_LANE0_SHIFT 2 262 # define DP_ADJUST_VOLTAGE_SWING_LANE1_MASK 0x30 263 # define DP_ADJUST_VOLTAGE_SWING_LANE1_SHIFT 4 264 # define DP_ADJUST_PRE_EMPHASIS_LANE1_MASK 0xc0 265 # define DP_ADJUST_PRE_EMPHASIS_LANE1_SHIFT 6 266 267 #define DP_TEST_REQUEST 0x218 268 # define DP_TEST_LINK_TRAINING (1 << 0) 269 # define DP_TEST_LINK_VIDEO_PATTERN (1 << 1) 270 # define DP_TEST_LINK_EDID_READ (1 << 2) 271 # define DP_TEST_LINK_PHY_TEST_PATTERN (1 << 3) /* DPCD >= 1.1 */ 272 # define DP_TEST_LINK_FAUX_PATTERN (1 << 4) /* DPCD >= 1.2 */ 273 274 #define DP_TEST_LINK_RATE 0x219 275 # define DP_LINK_RATE_162 (0x6) 276 # define DP_LINK_RATE_27 (0xa) 277 278 #define DP_TEST_LANE_COUNT 0x220 279 280 #define DP_TEST_PATTERN 0x221 281 282 #define DP_TEST_CRC_R_CR 0x240 283 #define DP_TEST_CRC_G_Y 0x242 284 #define DP_TEST_CRC_B_CB 0x244 285 286 #define DP_TEST_SINK_MISC 0x246 287 #define DP_TEST_CRC_SUPPORTED (1 << 5) 288 289 #define DP_TEST_RESPONSE 0x260 290 # define DP_TEST_ACK (1 << 0) 291 # define DP_TEST_NAK (1 << 1) 292 # define DP_TEST_EDID_CHECKSUM_WRITE (1 << 2) 293 294 #define DP_TEST_SINK 0x270 295 #define DP_TEST_SINK_START (1 << 0) 296 297 #define DP_SOURCE_OUI 0x300 298 #define DP_SINK_OUI 0x400 299 #define DP_BRANCH_OUI 0x500 300 301 #define DP_SET_POWER 0x600 302 # define DP_SET_POWER_D0 0x1 303 # define DP_SET_POWER_D3 0x2 304 # define DP_SET_POWER_MASK 0x3 305 306 #define DP_PSR_ERROR_STATUS 0x2006 /* XXX 1.2? */ 307 # define DP_PSR_LINK_CRC_ERROR (1 << 0) 308 # define DP_PSR_RFB_STORAGE_ERROR (1 << 1) 309 310 #define DP_PSR_ESI 0x2007 /* XXX 1.2? */ 311 # define DP_PSR_CAPS_CHANGE (1 << 0) 312 313 #define DP_PSR_STATUS 0x2008 /* XXX 1.2? */ 314 # define DP_PSR_SINK_INACTIVE 0 315 # define DP_PSR_SINK_ACTIVE_SRC_SYNCED 1 316 # define DP_PSR_SINK_ACTIVE_RFB 2 317 # define DP_PSR_SINK_ACTIVE_SINK_SYNCED 3 318 # define DP_PSR_SINK_ACTIVE_RESYNC 4 319 # define DP_PSR_SINK_INTERNAL_ERROR 7 320 # define DP_PSR_SINK_STATE_MASK 0x07 321 322 #define MODE_I2C_START 1 323 #define MODE_I2C_WRITE 2 324 #define MODE_I2C_READ 4 325 #define MODE_I2C_STOP 8 326 327 /** 328 * struct i2c_algo_dp_aux_data - driver interface structure for i2c over dp 329 * aux algorithm 330 * @running: set by the algo indicating whether an i2c is ongoing or whether 331 * the i2c bus is quiescent 332 * @address: i2c target address for the currently ongoing transfer 333 * @aux_ch: driver callback to transfer a single byte of the i2c payload 334 */ 335 struct i2c_algo_dp_aux_data { 336 bool running; 337 u16 address; 338 int (*aux_ch) (struct i2c_adapter *adapter, 339 int mode, uint8_t write_byte, 340 uint8_t *read_byte); 341 }; 342 343 int 344 i2c_dp_aux_add_bus(struct i2c_adapter *adapter); 345 346 347 #define DP_LINK_STATUS_SIZE 6 348 bool drm_dp_channel_eq_ok(const u8 link_status[DP_LINK_STATUS_SIZE], 349 int lane_count); 350 bool drm_dp_clock_recovery_ok(const u8 link_status[DP_LINK_STATUS_SIZE], 351 int lane_count); 352 u8 drm_dp_get_adjust_request_voltage(const u8 link_status[DP_LINK_STATUS_SIZE], 353 int lane); 354 u8 drm_dp_get_adjust_request_pre_emphasis(const u8 link_status[DP_LINK_STATUS_SIZE], 355 int lane); 356 357 #define DP_RECEIVER_CAP_SIZE 0xf 358 #define EDP_PSR_RECEIVER_CAP_SIZE 2 359 360 void drm_dp_link_train_clock_recovery_delay(const u8 dpcd[DP_RECEIVER_CAP_SIZE]); 361 void drm_dp_link_train_channel_eq_delay(const u8 dpcd[DP_RECEIVER_CAP_SIZE]); 362 363 u8 drm_dp_link_rate_to_bw_code(int link_rate); 364 int drm_dp_bw_code_to_link_rate(u8 link_bw); 365 366 struct edp_sdp_header { 367 u8 HB0; /* Secondary Data Packet ID */ 368 u8 HB1; /* Secondary Data Packet Type */ 369 u8 HB2; /* 7:5 reserved, 4:0 revision number */ 370 u8 HB3; /* 7:5 reserved, 4:0 number of valid data bytes */ 371 } __packed; 372 373 #define EDP_SDP_HEADER_REVISION_MASK 0x1F 374 #define EDP_SDP_HEADER_VALID_PAYLOAD_BYTES 0x1F 375 376 struct edp_vsc_psr { 377 struct edp_sdp_header sdp_header; 378 u8 DB0; /* Stereo Interface */ 379 u8 DB1; /* 0 - PSR State; 1 - Update RFB; 2 - CRC Valid */ 380 u8 DB2; /* CRC value bits 7:0 of the R or Cr component */ 381 u8 DB3; /* CRC value bits 15:8 of the R or Cr component */ 382 u8 DB4; /* CRC value bits 7:0 of the G or Y component */ 383 u8 DB5; /* CRC value bits 15:8 of the G or Y component */ 384 u8 DB6; /* CRC value bits 7:0 of the B or Cb component */ 385 u8 DB7; /* CRC value bits 15:8 of the B or Cb component */ 386 u8 DB8_31[24]; /* Reserved */ 387 } __packed; 388 389 #define EDP_VSC_PSR_STATE_ACTIVE (1<<0) 390 #define EDP_VSC_PSR_UPDATE_RFB (1<<1) 391 #define EDP_VSC_PSR_CRC_VALUES_VALID (1<<2) 392 393 static inline int 394 drm_dp_max_link_rate(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) 395 { 396 return drm_dp_bw_code_to_link_rate(dpcd[DP_MAX_LINK_RATE]); 397 } 398 399 static inline u8 400 drm_dp_max_lane_count(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) 401 { 402 return dpcd[DP_MAX_LANE_COUNT] & DP_MAX_LANE_COUNT_MASK; 403 } 404 405 static inline bool 406 drm_dp_enhanced_frame_cap(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) 407 { 408 return dpcd[DP_DPCD_REV] >= 0x11 && 409 (dpcd[DP_MAX_LANE_COUNT] & DP_ENHANCED_FRAME_CAP); 410 } 411 412 /* 413 * DisplayPort AUX channel 414 */ 415 416 /** 417 * struct drm_dp_aux_msg - DisplayPort AUX channel transaction 418 * @address: address of the (first) register to access 419 * @request: contains the type of transaction (see DP_AUX_* macros) 420 * @reply: upon completion, contains the reply type of the transaction 421 * @buffer: pointer to a transmission or reception buffer 422 * @size: size of @buffer 423 */ 424 struct drm_dp_aux_msg { 425 unsigned int address; 426 u8 request; 427 u8 reply; 428 void *buffer; 429 size_t size; 430 }; 431 432 /** 433 * struct drm_dp_aux - DisplayPort AUX channel 434 * @ddc: I2C adapter that can be used for I2C-over-AUX communication 435 * @dev: pointer to struct device that is the parent for this AUX channel 436 * @transfer: transfers a message representing a single AUX transaction 437 * 438 * The .dev field should be set to a pointer to the device that implements 439 * the AUX channel. 440 * 441 * The .name field may be used to specify the name of the I2C adapter. If set to 442 * NULL, dev_name() of .dev will be used. 443 * 444 * Drivers provide a hardware-specific implementation of how transactions 445 * are executed via the .transfer() function. A pointer to a drm_dp_aux_msg 446 * structure describing the transaction is passed into this function. Upon 447 * success, the implementation should return the number of payload bytes 448 * that were transferred, or a negative error-code on failure. Helpers 449 * propagate errors from the .transfer() function, with the exception of 450 * the -EBUSY error, which causes a transaction to be retried. On a short, 451 * helpers will return -EPROTO to make it simpler to check for failure. 452 * 453 * An AUX channel can also be used to transport I2C messages to a sink. A 454 * typical application of that is to access an EDID that's present in the 455 * sink device. The .transfer() function can also be used to execute such 456 * transactions. The drm_dp_aux_register_i2c_bus() function registers an 457 * I2C adapter that can be passed to drm_probe_ddc(). Upon removal, drivers 458 * should call drm_dp_aux_unregister_i2c_bus() to remove the I2C adapter. 459 * 460 * Note that the aux helper code assumes that the .transfer() function 461 * only modifies the reply field of the drm_dp_aux_msg structure. The 462 * retry logic and i2c helpers assume this is the case. 463 */ 464 struct drm_dp_aux { 465 const char *name; 466 struct i2c_adapter ddc; 467 struct device *dev; 468 469 ssize_t (*transfer)(struct drm_dp_aux *aux, 470 struct drm_dp_aux_msg *msg); 471 }; 472 473 ssize_t drm_dp_dpcd_read(struct drm_dp_aux *aux, unsigned int offset, 474 void *buffer, size_t size); 475 ssize_t drm_dp_dpcd_write(struct drm_dp_aux *aux, unsigned int offset, 476 void *buffer, size_t size); 477 478 /** 479 * drm_dp_dpcd_readb() - read a single byte from the DPCD 480 * @aux: DisplayPort AUX channel 481 * @offset: address of the register to read 482 * @valuep: location where the value of the register will be stored 483 * 484 * Returns the number of bytes transferred (1) on success, or a negative 485 * error code on failure. 486 */ 487 static inline ssize_t drm_dp_dpcd_readb(struct drm_dp_aux *aux, 488 unsigned int offset, u8 *valuep) 489 { 490 return drm_dp_dpcd_read(aux, offset, valuep, 1); 491 } 492 493 /** 494 * drm_dp_dpcd_writeb() - write a single byte to the DPCD 495 * @aux: DisplayPort AUX channel 496 * @offset: address of the register to write 497 * @value: value to write to the register 498 * 499 * Returns the number of bytes transferred (1) on success, or a negative 500 * error code on failure. 501 */ 502 static inline ssize_t drm_dp_dpcd_writeb(struct drm_dp_aux *aux, 503 unsigned int offset, u8 value) 504 { 505 return drm_dp_dpcd_write(aux, offset, &value, 1); 506 } 507 508 int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux, 509 u8 status[DP_LINK_STATUS_SIZE]); 510 511 /* 512 * DisplayPort link 513 */ 514 #define DP_LINK_CAP_ENHANCED_FRAMING (1 << 0) 515 516 struct drm_dp_link { 517 unsigned char revision; 518 unsigned int rate; 519 unsigned int num_lanes; 520 unsigned long capabilities; 521 }; 522 523 int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link); 524 int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link); 525 int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link); 526 527 int drm_dp_aux_register_i2c_bus(struct drm_dp_aux *aux); 528 void drm_dp_aux_unregister_i2c_bus(struct drm_dp_aux *aux); 529 530 #endif /* _DRM_DP_HELPER_H_ */ 531