include/cros_ec.h

   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