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