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 /** 67 * Read the ID of the CROS-EC device 68 * 69 * The ID is a string identifying the CROS-EC device. 70 * 71 * @param dev CROS-EC device 72 * @param id Place to put the ID 73 * @param maxlen Maximum length of the ID field 74 * @return 0 if ok, -1 on error 75 */ 76 int cros_ec_read_id(struct cros_ec_dev *dev, char *id, int maxlen); 77 78 /** 79 * Read a keyboard scan from the CROS-EC device 80 * 81 * Send a message requesting a keyboard scan and return the result 82 * 83 * @param dev CROS-EC device 84 * @param scan Place to put the scan results 85 * @return 0 if ok, -1 on error 86 */ 87 int cros_ec_scan_keyboard(struct cros_ec_dev *dev, struct mbkp_keyscan *scan); 88 89 /** 90 * Read which image is currently running on the CROS-EC device. 91 * 92 * @param dev CROS-EC device 93 * @param image Destination for image identifier 94 * @return 0 if ok, <0 on error 95 */ 96 int cros_ec_read_current_image(struct cros_ec_dev *dev, 97 enum ec_current_image *image); 98 99 /** 100 * Read the hash of the CROS-EC device firmware. 101 * 102 * @param dev CROS-EC device 103 * @param hash Destination for hash information 104 * @return 0 if ok, <0 on error 105 */ 106 int cros_ec_read_hash(struct cros_ec_dev *dev, 107 struct ec_response_vboot_hash *hash); 108 109 /** 110 * Send a reboot command to the CROS-EC device. 111 * 112 * Note that some reboot commands (such as EC_REBOOT_COLD) also reboot the AP. 113 * 114 * @param dev CROS-EC device 115 * @param cmd Reboot command 116 * @param flags Flags for reboot command (EC_REBOOT_FLAG_*) 117 * @return 0 if ok, <0 on error 118 */ 119 int cros_ec_reboot(struct cros_ec_dev *dev, enum ec_reboot_cmd cmd, 120 uint8_t flags); 121 122 /** 123 * Check if the CROS-EC device has an interrupt pending. 124 * 125 * Read the status of the external interrupt connected to the CROS-EC device. 126 * If no external interrupt is configured, this always returns 1. 127 * 128 * @param dev CROS-EC device 129 * @return 0 if no interrupt is pending 130 */ 131 int cros_ec_interrupt_pending(struct cros_ec_dev *dev); 132 133 enum { 134 CROS_EC_OK, 135 CROS_EC_ERR = 1, 136 CROS_EC_ERR_FDT_DECODE, 137 CROS_EC_ERR_CHECK_VERSION, 138 CROS_EC_ERR_READ_ID, 139 CROS_EC_ERR_DEV_INIT, 140 }; 141 142 /** 143 * Set up the Chromium OS matrix keyboard protocol 144 * 145 * @param blob Device tree blob containing setup information 146 * @param cros_ecp Returns pointer to the cros_ec device, or NULL if none 147 * @return 0 if we got an cros_ec device and all is well (or no cros_ec is 148 * expected), -ve if we should have an cros_ec device but failed to find 149 * one, or init failed (-CROS_EC_ERR_...). 150 */ 151 int cros_ec_init(const void *blob, struct cros_ec_dev **cros_ecp); 152 153 /** 154 * Read information about the keyboard matrix 155 * 156 * @param dev CROS-EC device 157 * @param info Place to put the info structure 158 */ 159 int cros_ec_info(struct cros_ec_dev *dev, 160 struct ec_response_cros_ec_info *info); 161 162 /** 163 * Read the host event flags 164 * 165 * @param dev CROS-EC device 166 * @param events_ptr Destination for event flags. Not changed on error. 167 * @return 0 if ok, <0 on error 168 */ 169 int cros_ec_get_host_events(struct cros_ec_dev *dev, uint32_t *events_ptr); 170 171 /** 172 * Clear the specified host event flags 173 * 174 * @param dev CROS-EC device 175 * @param events Event flags to clear 176 * @return 0 if ok, <0 on error 177 */ 178 int cros_ec_clear_host_events(struct cros_ec_dev *dev, uint32_t events); 179 180 /** 181 * Get/set flash protection 182 * 183 * @param dev CROS-EC device 184 * @param set_mask Mask of flags to set; if 0, just retrieves existing 185 * protection state without changing it. 186 * @param set_flags New flag values; only bits in set_mask are applied; 187 * ignored if set_mask=0. 188 * @param prot Destination for updated protection state from EC. 189 * @return 0 if ok, <0 on error 190 */ 191 int cros_ec_flash_protect(struct cros_ec_dev *dev, 192 uint32_t set_mask, uint32_t set_flags, 193 struct ec_response_flash_protect *resp); 194 195 196 /** 197 * Run internal tests on the cros_ec interface. 198 * 199 * @param dev CROS-EC device 200 * @return 0 if ok, <0 if the test failed 201 */ 202 int cros_ec_test(struct cros_ec_dev *dev); 203 204 /** 205 * Update the EC RW copy. 206 * 207 * @param dev CROS-EC device 208 * @param image the content to write 209 * @param imafge_size content length 210 * @return 0 if ok, <0 if the test failed 211 */ 212 int cros_ec_flash_update_rw(struct cros_ec_dev *dev, 213 const uint8_t *image, int image_size); 214 215 /** 216 * Return a pointer to the board's CROS-EC device 217 * 218 * This should be implemented by board files. 219 * 220 * @return pointer to CROS-EC device, or NULL if none is available 221 */ 222 struct cros_ec_dev *board_get_cros_ec_dev(void); 223 224 225 /* Internal interfaces */ 226 int cros_ec_i2c_init(struct cros_ec_dev *dev, const void *blob); 227 int cros_ec_spi_init(struct cros_ec_dev *dev, const void *blob); 228 int cros_ec_lpc_init(struct cros_ec_dev *dev, const void *blob); 229 230 /** 231 * Read information from the fdt for the i2c cros_ec interface 232 * 233 * @param dev CROS-EC device 234 * @param blob Device tree blob 235 * @return 0 if ok, -1 if we failed to read all required information 236 */ 237 int cros_ec_i2c_decode_fdt(struct cros_ec_dev *dev, const void *blob); 238 239 /** 240 * Read information from the fdt for the spi cros_ec interface 241 * 242 * @param dev CROS-EC device 243 * @param blob Device tree blob 244 * @return 0 if ok, -1 if we failed to read all required information 245 */ 246 int cros_ec_spi_decode_fdt(struct cros_ec_dev *dev, const void *blob); 247 248 /** 249 * Check whether the LPC interface supports new-style commands. 250 * 251 * LPC has its own way of doing this, which involves checking LPC values 252 * visible to the host. Do this, and update dev->cmd_version_is_supported 253 * accordingly. 254 * 255 * @param dev CROS-EC device to check 256 */ 257 int cros_ec_lpc_check_version(struct cros_ec_dev *dev); 258 259 /** 260 * Send a command to an I2C CROS-EC device and return the reply. 261 * 262 * This rather complicated function deals with sending both old-style and 263 * new-style commands. The old ones have just a command byte and arguments. 264 * The new ones have version, command, arg-len, [args], chksum so are 3 bytes 265 * longer. 266 * 267 * The device's internal input/output buffers are used. 268 * 269 * @param dev CROS-EC device 270 * @param cmd Command to send (EC_CMD_...) 271 * @param cmd_version Version of command to send (EC_VER_...) 272 * @param dout Output data (may be NULL If dout_len=0) 273 * @param dout_len Size of output data in bytes 274 * @param dinp Returns pointer to response data 275 * @param din_len Maximum size of response in bytes 276 * @return number of bytes in response, or -1 on error 277 */ 278 int cros_ec_i2c_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version, 279 const uint8_t *dout, int dout_len, 280 uint8_t **dinp, int din_len); 281 282 /** 283 * Send a command to a LPC CROS-EC device and return the reply. 284 * 285 * The device's internal input/output buffers are used. 286 * 287 * @param dev CROS-EC device 288 * @param cmd Command to send (EC_CMD_...) 289 * @param cmd_version Version of command to send (EC_VER_...) 290 * @param dout Output data (may be NULL If dout_len=0) 291 * @param dout_len Size of output data in bytes 292 * @param dinp Returns pointer to response data 293 * @param din_len Maximum size of response in bytes 294 * @return number of bytes in response, or -1 on error 295 */ 296 int cros_ec_lpc_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version, 297 const uint8_t *dout, int dout_len, 298 uint8_t **dinp, int din_len); 299 300 int cros_ec_spi_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version, 301 const uint8_t *dout, int dout_len, 302 uint8_t **dinp, int din_len); 303 304 /** 305 * Dump a block of data for a command. 306 * 307 * @param name Name for data (e.g. 'in', 'out') 308 * @param cmd Command number associated with data, or -1 for none 309 * @param data Data block to dump 310 * @param len Length of data block to dump 311 */ 312 void cros_ec_dump_data(const char *name, int cmd, const uint8_t *data, int len); 313 314 /** 315 * Calculate a simple 8-bit checksum of a data block 316 * 317 * @param data Data block to checksum 318 * @param size Size of data block in bytes 319 * @return checksum value (0 to 255) 320 */ 321 int cros_ec_calc_checksum(const uint8_t *data, int size); 322 323 /** 324 * Decode a flash region parameter 325 * 326 * @param argc Number of params remaining 327 * @param argv List of remaining parameters 328 * @return flash region (EC_FLASH_REGION_...) or -1 on error 329 */ 330 int cros_ec_decode_region(int argc, char * const argv[]); 331 332 int cros_ec_flash_erase(struct cros_ec_dev *dev, uint32_t offset, 333 uint32_t size); 334 335 /** 336 * Read data from the flash 337 * 338 * Read an arbitrary amount of data from the EC flash, by repeatedly reading 339 * small blocks. 340 * 341 * The offset starts at 0. You can obtain the region information from 342 * cros_ec_flash_offset() to find out where to read for a particular region. 343 * 344 * @param dev CROS-EC device 345 * @param data Pointer to data buffer to read into 346 * @param offset Offset within flash to read from 347 * @param size Number of bytes to read 348 * @return 0 if ok, -1 on error 349 */ 350 int cros_ec_flash_read(struct cros_ec_dev *dev, uint8_t *data, uint32_t offset, 351 uint32_t size); 352 353 /** 354 * Write data to the flash 355 * 356 * Write an arbitrary amount of data to the EC flash, by repeatedly writing 357 * small blocks. 358 * 359 * The offset starts at 0. You can obtain the region information from 360 * cros_ec_flash_offset() to find out where to write for a particular region. 361 * 362 * Attempting to write to the region where the EC is currently running from 363 * will result in an error. 364 * 365 * @param dev CROS-EC device 366 * @param data Pointer to data buffer to write 367 * @param offset Offset within flash to write to. 368 * @param size Number of bytes to write 369 * @return 0 if ok, -1 on error 370 */ 371 int cros_ec_flash_write(struct cros_ec_dev *dev, const uint8_t *data, 372 uint32_t offset, uint32_t size); 373 374 /** 375 * Obtain position and size of a flash region 376 * 377 * @param dev CROS-EC device 378 * @param region Flash region to query 379 * @param offset Returns offset of flash region in EC flash 380 * @param size Returns size of flash region 381 * @return 0 if ok, -1 on error 382 */ 383 int cros_ec_flash_offset(struct cros_ec_dev *dev, enum ec_flash_region region, 384 uint32_t *offset, uint32_t *size); 385 386 /** 387 * Read/write VbNvContext from/to a CROS-EC device. 388 * 389 * @param dev CROS-EC device 390 * @param block Buffer of VbNvContext to be read/write 391 * @return 0 if ok, -1 on error 392 */ 393 int cros_ec_read_vbnvcontext(struct cros_ec_dev *dev, uint8_t *block); 394 int cros_ec_write_vbnvcontext(struct cros_ec_dev *dev, const uint8_t *block); 395 396 /** 397 * Read the version information for the EC images 398 * 399 * @param dev CROS-EC device 400 * @param versionp This is set to point to the version information 401 * @return 0 if ok, -1 on error 402 */ 403 int cros_ec_read_version(struct cros_ec_dev *dev, 404 struct ec_response_get_version **versionp); 405 406 /** 407 * Read the build information for the EC 408 * 409 * @param dev CROS-EC device 410 * @param versionp This is set to point to the build string 411 * @return 0 if ok, -1 on error 412 */ 413 int cros_ec_read_build_info(struct cros_ec_dev *dev, char **strp); 414 415 /** 416 * Switch on/off a LDO / FET. 417 * 418 * @param dev CROS-EC device 419 * @param index index of the LDO/FET to switch 420 * @param state new state of the LDO/FET : EC_LDO_STATE_ON|OFF 421 * @return 0 if ok, -1 on error 422 */ 423 int cros_ec_set_ldo(struct cros_ec_dev *dev, uint8_t index, uint8_t state); 424 425 /** 426 * Read back a LDO / FET current state. 427 * 428 * @param dev CROS-EC device 429 * @param index index of the LDO/FET to switch 430 * @param state current state of the LDO/FET : EC_LDO_STATE_ON|OFF 431 * @return 0 if ok, -1 on error 432 */ 433 int cros_ec_get_ldo(struct cros_ec_dev *dev, uint8_t index, uint8_t *state); 434 #endif 435