1 /* 2 * Chromium OS cros_ec driver 3 * 4 * Copyright (c) 2012 The Chromium OS Authors. 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9 #ifndef _CROS_EC_H 10 #define _CROS_EC_H 11 12 #include <linux/compiler.h> 13 #include <ec_commands.h> 14 #include <fdtdec.h> 15 #include <cros_ec_message.h> 16 17 /* Which interface is the device on? */ 18 enum cros_ec_interface_t { 19 CROS_EC_IF_NONE, 20 CROS_EC_IF_SPI, 21 CROS_EC_IF_I2C, 22 CROS_EC_IF_LPC, /* Intel Low Pin Count interface */ 23 CROS_EC_IF_SANDBOX, 24 }; 25 26 /* Our configuration information */ 27 struct cros_ec_dev { 28 enum cros_ec_interface_t interface; 29 struct spi_slave *spi; /* Our SPI slave, if using SPI */ 30 int node; /* Our node */ 31 int parent_node; /* Our parent node (interface) */ 32 unsigned int cs; /* Our chip select */ 33 unsigned int addr; /* Device address (for I2C) */ 34 unsigned int bus_num; /* Bus number (for I2C) */ 35 unsigned int max_frequency; /* Maximum interface frequency */ 36 struct fdt_gpio_state ec_int; /* GPIO used as EC interrupt line */ 37 int protocol_version; /* Protocol version to use */ 38 int optimise_flash_write; /* Don't write erased flash blocks */ 39 40 /* 41 * These two buffers will always be dword-aligned and include enough 42 * space for up to 7 word-alignment bytes also, so we can ensure that 43 * the body of the message is always dword-aligned (64-bit). 44 * 45 * We use this alignment to keep ARM and x86 happy. Probably word 46 * alignment would be OK, there might be a small performance advantage 47 * to using dword. 48 */ 49 uint8_t din[ALIGN(MSG_BYTES + sizeof(int64_t), sizeof(int64_t))] 50 __aligned(sizeof(int64_t)); 51 uint8_t dout[ALIGN(MSG_BYTES + sizeof(int64_t), sizeof(int64_t))] 52 __aligned(sizeof(int64_t)); 53 }; 54 55 /* 56 * Hard-code the number of columns we happen to know we have right now. It 57 * would be more correct to call cros_ec_info() at startup and determine the 58 * actual number of keyboard cols from there. 59 */ 60 #define CROS_EC_KEYSCAN_COLS 13 61 62 /* Information returned by a key scan */ 63 struct mbkp_keyscan { 64 uint8_t data[CROS_EC_KEYSCAN_COLS]; 65 }; 66 67 /* Holds information about the Chrome EC */ 68 struct fdt_cros_ec { 69 struct fmap_entry flash; /* Address and size of EC flash */ 70 /* 71 * Byte value of erased flash, or -1 if not known. It is normally 72 * 0xff but some flash devices use 0 (e.g. STM32Lxxx) 73 */ 74 int flash_erase_value; 75 struct fmap_entry region[EC_FLASH_REGION_COUNT]; 76 }; 77 78 /** 79 * Read the ID of the CROS-EC device 80 * 81 * The ID is a string identifying the CROS-EC device. 82 * 83 * @param dev CROS-EC device 84 * @param id Place to put the ID 85 * @param maxlen Maximum length of the ID field 86 * @return 0 if ok, -1 on error 87 */ 88 int cros_ec_read_id(struct cros_ec_dev *dev, char *id, int maxlen); 89 90 /** 91 * Read a keyboard scan from the CROS-EC device 92 * 93 * Send a message requesting a keyboard scan and return the result 94 * 95 * @param dev CROS-EC device 96 * @param scan Place to put the scan results 97 * @return 0 if ok, -1 on error 98 */ 99 int cros_ec_scan_keyboard(struct cros_ec_dev *dev, struct mbkp_keyscan *scan); 100 101 /** 102 * Read which image is currently running on the CROS-EC device. 103 * 104 * @param dev CROS-EC device 105 * @param image Destination for image identifier 106 * @return 0 if ok, <0 on error 107 */ 108 int cros_ec_read_current_image(struct cros_ec_dev *dev, 109 enum ec_current_image *image); 110 111 /** 112 * Read the hash of the CROS-EC device firmware. 113 * 114 * @param dev CROS-EC device 115 * @param hash Destination for hash information 116 * @return 0 if ok, <0 on error 117 */ 118 int cros_ec_read_hash(struct cros_ec_dev *dev, 119 struct ec_response_vboot_hash *hash); 120 121 /** 122 * Send a reboot command to the CROS-EC device. 123 * 124 * Note that some reboot commands (such as EC_REBOOT_COLD) also reboot the AP. 125 * 126 * @param dev CROS-EC device 127 * @param cmd Reboot command 128 * @param flags Flags for reboot command (EC_REBOOT_FLAG_*) 129 * @return 0 if ok, <0 on error 130 */ 131 int cros_ec_reboot(struct cros_ec_dev *dev, enum ec_reboot_cmd cmd, 132 uint8_t flags); 133 134 /** 135 * Check if the CROS-EC device has an interrupt pending. 136 * 137 * Read the status of the external interrupt connected to the CROS-EC device. 138 * If no external interrupt is configured, this always returns 1. 139 * 140 * @param dev CROS-EC device 141 * @return 0 if no interrupt is pending 142 */ 143 int cros_ec_interrupt_pending(struct cros_ec_dev *dev); 144 145 enum { 146 CROS_EC_OK, 147 CROS_EC_ERR = 1, 148 CROS_EC_ERR_FDT_DECODE, 149 CROS_EC_ERR_CHECK_VERSION, 150 CROS_EC_ERR_READ_ID, 151 CROS_EC_ERR_DEV_INIT, 152 }; 153 154 /** 155 * Initialise the Chromium OS EC driver 156 * 157 * @param blob Device tree blob containing setup information 158 * @param cros_ecp Returns pointer to the cros_ec device, or NULL if none 159 * @return 0 if we got an cros_ec device and all is well (or no cros_ec is 160 * expected), -ve if we should have an cros_ec device but failed to find 161 * one, or init failed (-CROS_EC_ERR_...). 162 */ 163 int cros_ec_init(const void *blob, struct cros_ec_dev **cros_ecp); 164 165 /** 166 * Read information about the keyboard matrix 167 * 168 * @param dev CROS-EC device 169 * @param info Place to put the info structure 170 */ 171 int cros_ec_info(struct cros_ec_dev *dev, 172 struct ec_response_mkbp_info *info); 173 174 /** 175 * Read the host event flags 176 * 177 * @param dev CROS-EC device 178 * @param events_ptr Destination for event flags. Not changed on error. 179 * @return 0 if ok, <0 on error 180 */ 181 int cros_ec_get_host_events(struct cros_ec_dev *dev, uint32_t *events_ptr); 182 183 /** 184 * Clear the specified host event flags 185 * 186 * @param dev CROS-EC device 187 * @param events Event flags to clear 188 * @return 0 if ok, <0 on error 189 */ 190 int cros_ec_clear_host_events(struct cros_ec_dev *dev, uint32_t events); 191 192 /** 193 * Get/set flash protection 194 * 195 * @param dev CROS-EC device 196 * @param set_mask Mask of flags to set; if 0, just retrieves existing 197 * protection state without changing it. 198 * @param set_flags New flag values; only bits in set_mask are applied; 199 * ignored if set_mask=0. 200 * @param prot Destination for updated protection state from EC. 201 * @return 0 if ok, <0 on error 202 */ 203 int cros_ec_flash_protect(struct cros_ec_dev *dev, 204 uint32_t set_mask, uint32_t set_flags, 205 struct ec_response_flash_protect *resp); 206 207 208 /** 209 * Run internal tests on the cros_ec interface. 210 * 211 * @param dev CROS-EC device 212 * @return 0 if ok, <0 if the test failed 213 */ 214 int cros_ec_test(struct cros_ec_dev *dev); 215 216 /** 217 * Update the EC RW copy. 218 * 219 * @param dev CROS-EC device 220 * @param image the content to write 221 * @param imafge_size content length 222 * @return 0 if ok, <0 if the test failed 223 */ 224 int cros_ec_flash_update_rw(struct cros_ec_dev *dev, 225 const uint8_t *image, int image_size); 226 227 /** 228 * Return a pointer to the board's CROS-EC device 229 * 230 * This should be implemented by board files. 231 * 232 * @return pointer to CROS-EC device, or NULL if none is available 233 */ 234 struct cros_ec_dev *board_get_cros_ec_dev(void); 235 236 237 /* Internal interfaces */ 238 int cros_ec_i2c_init(struct cros_ec_dev *dev, const void *blob); 239 int cros_ec_spi_init(struct cros_ec_dev *dev, const void *blob); 240 int cros_ec_lpc_init(struct cros_ec_dev *dev, const void *blob); 241 int cros_ec_sandbox_init(struct cros_ec_dev *dev, const void *blob); 242 243 /** 244 * Read information from the fdt for the i2c cros_ec interface 245 * 246 * @param dev CROS-EC device 247 * @param blob Device tree blob 248 * @return 0 if ok, -1 if we failed to read all required information 249 */ 250 int cros_ec_i2c_decode_fdt(struct cros_ec_dev *dev, const void *blob); 251 252 /** 253 * Read information from the fdt for the spi cros_ec interface 254 * 255 * @param dev CROS-EC device 256 * @param blob Device tree blob 257 * @return 0 if ok, -1 if we failed to read all required information 258 */ 259 int cros_ec_spi_decode_fdt(struct cros_ec_dev *dev, const void *blob); 260 261 /** 262 * Read information from the fdt for the sandbox cros_ec interface 263 * 264 * @param dev CROS-EC device 265 * @param blob Device tree blob 266 * @return 0 if ok, -1 if we failed to read all required information 267 */ 268 int cros_ec_sandbox_decode_fdt(struct cros_ec_dev *dev, const void *blob); 269 270 /** 271 * Check whether the LPC interface supports new-style commands. 272 * 273 * LPC has its own way of doing this, which involves checking LPC values 274 * visible to the host. Do this, and update dev->protocol_version accordingly. 275 * 276 * @param dev CROS-EC device to check 277 */ 278 int cros_ec_lpc_check_version(struct cros_ec_dev *dev); 279 280 /** 281 * Send a command to an I2C CROS-EC device and return the reply. 282 * 283 * This rather complicated function deals with sending both old-style and 284 * new-style commands. The old ones have just a command byte and arguments. 285 * The new ones have version, command, arg-len, [args], chksum so are 3 bytes 286 * longer. 287 * 288 * The device's internal input/output buffers are used. 289 * 290 * @param dev CROS-EC device 291 * @param cmd Command to send (EC_CMD_...) 292 * @param cmd_version Version of command to send (EC_VER_...) 293 * @param dout Output data (may be NULL If dout_len=0) 294 * @param dout_len Size of output data in bytes 295 * @param dinp Returns pointer to response data 296 * @param din_len Maximum size of response in bytes 297 * @return number of bytes in response, or -1 on error 298 */ 299 int cros_ec_i2c_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version, 300 const uint8_t *dout, int dout_len, 301 uint8_t **dinp, int din_len); 302 303 /** 304 * Send a command to a LPC CROS-EC device and return the reply. 305 * 306 * The device's internal input/output buffers are used. 307 * 308 * @param dev CROS-EC device 309 * @param cmd Command to send (EC_CMD_...) 310 * @param cmd_version Version of command to send (EC_VER_...) 311 * @param dout Output data (may be NULL If dout_len=0) 312 * @param dout_len Size of output data in bytes 313 * @param dinp Returns pointer to response data 314 * @param din_len Maximum size of response in bytes 315 * @return number of bytes in response, or -1 on error 316 */ 317 int cros_ec_lpc_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version, 318 const uint8_t *dout, int dout_len, 319 uint8_t **dinp, int din_len); 320 321 int cros_ec_spi_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version, 322 const uint8_t *dout, int dout_len, 323 uint8_t **dinp, int din_len); 324 325 /** 326 * Send a packet to a CROS-EC device and return the response packet. 327 * 328 * Expects the request packet to be stored in dev->dout. Stores the response 329 * packet in dev->din. 330 * 331 * @param dev CROS-EC device 332 * @param out_bytes Size of request packet to output 333 * @param in_bytes Maximum size of response packet to receive 334 * @return number of bytes in response packet, or <0 on error 335 */ 336 int cros_ec_spi_packet(struct cros_ec_dev *dev, int out_bytes, int in_bytes); 337 int cros_ec_sandbox_packet(struct cros_ec_dev *dev, int out_bytes, 338 int in_bytes); 339 340 /** 341 * Dump a block of data for a command. 342 * 343 * @param name Name for data (e.g. 'in', 'out') 344 * @param cmd Command number associated with data, or -1 for none 345 * @param data Data block to dump 346 * @param len Length of data block to dump 347 */ 348 void cros_ec_dump_data(const char *name, int cmd, const uint8_t *data, int len); 349 350 /** 351 * Calculate a simple 8-bit checksum of a data block 352 * 353 * @param data Data block to checksum 354 * @param size Size of data block in bytes 355 * @return checksum value (0 to 255) 356 */ 357 int cros_ec_calc_checksum(const uint8_t *data, int size); 358 359 /** 360 * Decode a flash region parameter 361 * 362 * @param argc Number of params remaining 363 * @param argv List of remaining parameters 364 * @return flash region (EC_FLASH_REGION_...) or -1 on error 365 */ 366 int cros_ec_decode_region(int argc, char * const argv[]); 367 368 int cros_ec_flash_erase(struct cros_ec_dev *dev, uint32_t offset, 369 uint32_t size); 370 371 /** 372 * Read data from the flash 373 * 374 * Read an arbitrary amount of data from the EC flash, by repeatedly reading 375 * small blocks. 376 * 377 * The offset starts at 0. You can obtain the region information from 378 * cros_ec_flash_offset() to find out where to read for a particular region. 379 * 380 * @param dev CROS-EC device 381 * @param data Pointer to data buffer to read into 382 * @param offset Offset within flash to read from 383 * @param size Number of bytes to read 384 * @return 0 if ok, -1 on error 385 */ 386 int cros_ec_flash_read(struct cros_ec_dev *dev, uint8_t *data, uint32_t offset, 387 uint32_t size); 388 389 /** 390 * Write data to the flash 391 * 392 * Write an arbitrary amount of data to the EC flash, by repeatedly writing 393 * small blocks. 394 * 395 * The offset starts at 0. You can obtain the region information from 396 * cros_ec_flash_offset() to find out where to write for a particular region. 397 * 398 * Attempting to write to the region where the EC is currently running from 399 * will result in an error. 400 * 401 * @param dev CROS-EC device 402 * @param data Pointer to data buffer to write 403 * @param offset Offset within flash to write to. 404 * @param size Number of bytes to write 405 * @return 0 if ok, -1 on error 406 */ 407 int cros_ec_flash_write(struct cros_ec_dev *dev, const uint8_t *data, 408 uint32_t offset, uint32_t size); 409 410 /** 411 * Obtain position and size of a flash region 412 * 413 * @param dev CROS-EC device 414 * @param region Flash region to query 415 * @param offset Returns offset of flash region in EC flash 416 * @param size Returns size of flash region 417 * @return 0 if ok, -1 on error 418 */ 419 int cros_ec_flash_offset(struct cros_ec_dev *dev, enum ec_flash_region region, 420 uint32_t *offset, uint32_t *size); 421 422 /** 423 * Read/write VbNvContext from/to a CROS-EC device. 424 * 425 * @param dev CROS-EC device 426 * @param block Buffer of VbNvContext to be read/write 427 * @return 0 if ok, -1 on error 428 */ 429 int cros_ec_read_vbnvcontext(struct cros_ec_dev *dev, uint8_t *block); 430 int cros_ec_write_vbnvcontext(struct cros_ec_dev *dev, const uint8_t *block); 431 432 /** 433 * Read the version information for the EC images 434 * 435 * @param dev CROS-EC device 436 * @param versionp This is set to point to the version information 437 * @return 0 if ok, -1 on error 438 */ 439 int cros_ec_read_version(struct cros_ec_dev *dev, 440 struct ec_response_get_version **versionp); 441 442 /** 443 * Read the build information for the EC 444 * 445 * @param dev CROS-EC device 446 * @param versionp This is set to point to the build string 447 * @return 0 if ok, -1 on error 448 */ 449 int cros_ec_read_build_info(struct cros_ec_dev *dev, char **strp); 450 451 /** 452 * Switch on/off a LDO / FET. 453 * 454 * @param dev CROS-EC device 455 * @param index index of the LDO/FET to switch 456 * @param state new state of the LDO/FET : EC_LDO_STATE_ON|OFF 457 * @return 0 if ok, -1 on error 458 */ 459 int cros_ec_set_ldo(struct cros_ec_dev *dev, uint8_t index, uint8_t state); 460 461 /** 462 * Read back a LDO / FET current state. 463 * 464 * @param dev CROS-EC device 465 * @param index index of the LDO/FET to switch 466 * @param state current state of the LDO/FET : EC_LDO_STATE_ON|OFF 467 * @return 0 if ok, -1 on error 468 */ 469 int cros_ec_get_ldo(struct cros_ec_dev *dev, uint8_t index, uint8_t *state); 470 471 /** 472 * Initialize the Chrome OS EC at board initialization time. 473 * 474 * @return 0 if ok, -ve on error 475 */ 476 int cros_ec_board_init(void); 477 478 /** 479 * Get access to the error reported when cros_ec_board_init() was called 480 * 481 * This permits delayed reporting of the EC error if it failed during 482 * early init. 483 * 484 * @return error (0 if there was no error, -ve if there was an error) 485 */ 486 int cros_ec_get_error(void); 487 488 /** 489 * Returns information from the FDT about the Chrome EC flash 490 * 491 * @param blob FDT blob to use 492 * @param config Structure to use to return information 493 */ 494 int cros_ec_decode_ec_flash(const void *blob, struct fdt_cros_ec *config); 495 496 /** 497 * Check the current keyboard state, in case recovery mode is requested. 498 * This function is for sandbox only. 499 * 500 * @param ec CROS-EC device 501 */ 502 void cros_ec_check_keyboard(struct cros_ec_dev *dev); 503 504 /* 505 * Tunnel an I2C transfer to the EC 506 * 507 * @param dev CROS-EC device 508 * @param chip Chip address (7-bit I2C address) 509 * @param addr Register address to read/write 510 * @param alen Length of register address in bytes 511 * @param buffer Buffer containing data to read/write 512 * @param len Length of buffer 513 * @param is_read 1 if this is a read, 0 if this is a write 514 */ 515 int cros_ec_i2c_xfer(struct cros_ec_dev *dev, uchar chip, uint addr, 516 int alen, uchar *buffer, int len, int is_read); 517 518 #endif 519