include/cros_ec.h

   1 /*
   2  * Chromium OS cros_ec driver
   3  *
   4  * Copyright (c) 2012 The Chromium OS Authors.
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 #ifndef _CROS_EC_H
  25 #define _CROS_EC_H
  26
  27 #include <linux/compiler.h>
  28 #include <ec_commands.h>
  29 #include <fdtdec.h>
  30 #include <cros_ec_message.h>
  31
  32 /* Which interface is the device on? */
  33 enum cros_ec_interface_t {
  34         CROS_EC_IF_NONE,
  35         CROS_EC_IF_SPI,
  36         CROS_EC_IF_I2C,
  37         CROS_EC_IF_LPC, /* Intel Low Pin Count interface */
  38 };
  39
  40 /* Our configuration information */
  41 struct cros_ec_dev {
  42         enum cros_ec_interface_t interface;
  43         struct spi_slave *spi;          /* Our SPI slave, if using SPI */
  44         int node;                       /* Our node */
  45         int parent_node;                /* Our parent node (interface) */
  46         unsigned int cs;                /* Our chip select */
  47         unsigned int addr;              /* Device address (for I2C) */
  48         unsigned int bus_num;           /* Bus number (for I2C) */
  49         unsigned int max_frequency;     /* Maximum interface frequency */
  50         struct fdt_gpio_state ec_int;   /* GPIO used as EC interrupt line */
  51         int cmd_version_is_supported;   /* Device supports command versions */
  52         int optimise_flash_write;       /* Don't write erased flash blocks */
  53
  54         /*
  55          * These two buffers will always be dword-aligned and include enough
  56          * space for up to 7 word-alignment bytes also, so we can ensure that
  57          * the body of the message is always dword-aligned (64-bit).
  58          *
  59          * We use this alignment to keep ARM and x86 happy. Probably word
  60          * alignment would be OK, there might be a small performance advantage
  61          * to using dword.
  62          */
  63         uint8_t din[ALIGN(MSG_BYTES + sizeof(int64_t), sizeof(int64_t))]
  64                 __aligned(sizeof(int64_t));
  65         uint8_t dout[ALIGN(MSG_BYTES + sizeof(int64_t), sizeof(int64_t))]
  66                 __aligned(sizeof(int64_t));
  67 };
  68
  69 /*
  70  * Hard-code the number of columns we happen to know we have right now.  It
  71  * would be more correct to call cros_ec_info() at startup and determine the
  72  * actual number of keyboard cols from there.
  73  */
  74 #define CROS_EC_KEYSCAN_COLS 13
  75
  76 /* Information returned by a key scan */
  77 struct mbkp_keyscan {
  78         uint8_t data[CROS_EC_KEYSCAN_COLS];
  79 };
  80
  81 /**
  82  * Read the ID of the CROS-EC device
  83  *
  84  * The ID is a string identifying the CROS-EC device.
  85  *
  86  * @param dev           CROS-EC device
  87  * @param id            Place to put the ID
  88  * @param maxlen        Maximum length of the ID field
  89  * @return 0 if ok, -1 on error
  90  */
  91 int cros_ec_read_id(struct cros_ec_dev *dev, char *id, int maxlen);
  92
  93 /**
  94  * Read a keyboard scan from the CROS-EC device
  95  *
  96  * Send a message requesting a keyboard scan and return the result
  97  *
  98  * @param dev           CROS-EC device
  99  * @param scan          Place to put the scan results
 100  * @return 0 if ok, -1 on error
 101  */
 102 int cros_ec_scan_keyboard(struct cros_ec_dev *dev, struct mbkp_keyscan *scan);
 103
 104 /**
 105  * Read which image is currently running on the CROS-EC device.
 106  *
 107  * @param dev           CROS-EC device
 108  * @param image         Destination for image identifier
 109  * @return 0 if ok, <0 on error
 110  */
 111 int cros_ec_read_current_image(struct cros_ec_dev *dev,
 112                 enum ec_current_image *image);
 113
 114 /**
 115  * Read the hash of the CROS-EC device firmware.
 116  *
 117  * @param dev           CROS-EC device
 118  * @param hash          Destination for hash information
 119  * @return 0 if ok, <0 on error
 120  */
 121 int cros_ec_read_hash(struct cros_ec_dev *dev,
 122                 struct ec_response_vboot_hash *hash);
 123
 124 /**
 125  * Send a reboot command to the CROS-EC device.
 126  *
 127  * Note that some reboot commands (such as EC_REBOOT_COLD) also reboot the AP.
 128  *
 129  * @param dev           CROS-EC device
 130  * @param cmd           Reboot command
 131  * @param flags         Flags for reboot command (EC_REBOOT_FLAG_*)
 132  * @return 0 if ok, <0 on error
 133  */
 134 int cros_ec_reboot(struct cros_ec_dev *dev, enum ec_reboot_cmd cmd,
 135                 uint8_t flags);
 136
 137 /**
 138  * Check if the CROS-EC device has an interrupt pending.
 139  *
 140  * Read the status of the external interrupt connected to the CROS-EC device.
 141  * If no external interrupt is configured, this always returns 1.
 142  *
 143  * @param dev           CROS-EC device
 144  * @return 0 if no interrupt is pending
 145  */
 146 int cros_ec_interrupt_pending(struct cros_ec_dev *dev);
 147
 148 enum {
 149         CROS_EC_OK,
 150         CROS_EC_ERR = 1,
 151         CROS_EC_ERR_FDT_DECODE,
 152         CROS_EC_ERR_CHECK_VERSION,
 153         CROS_EC_ERR_READ_ID,
 154         CROS_EC_ERR_DEV_INIT,
 155 };
 156
 157 /**
 158  * Set up the Chromium OS matrix keyboard protocol
 159  *
 160  * @param blob          Device tree blob containing setup information
 161  * @param cros_ecp        Returns pointer to the cros_ec device, or NULL if none
 162  * @return 0 if we got an cros_ec device and all is well (or no cros_ec is
 163  *      expected), -ve if we should have an cros_ec device but failed to find
 164  *      one, or init failed (-CROS_EC_ERR_...).
 165  */
 166 int cros_ec_init(const void *blob, struct cros_ec_dev **cros_ecp);
 167
 168 /**
 169  * Read information about the keyboard matrix
 170  *
 171  * @param dev           CROS-EC device
 172  * @param info          Place to put the info structure
 173  */
 174 int cros_ec_info(struct cros_ec_dev *dev,
 175                 struct ec_response_cros_ec_info *info);
 176
 177 /**
 178  * Read the host event flags
 179  *
 180  * @param dev           CROS-EC device
 181  * @param events_ptr    Destination for event flags.  Not changed on error.
 182  * @return 0 if ok, <0 on error
 183  */
 184 int cros_ec_get_host_events(struct cros_ec_dev *dev, uint32_t *events_ptr);
 185
 186 /**
 187  * Clear the specified host event flags
 188  *
 189  * @param dev           CROS-EC device
 190  * @param events        Event flags to clear
 191  * @return 0 if ok, <0 on error
 192  */
 193 int cros_ec_clear_host_events(struct cros_ec_dev *dev, uint32_t events);
 194
 195 /**
 196  * Get/set flash protection
 197  *
 198  * @param dev           CROS-EC device
 199  * @param set_mask      Mask of flags to set; if 0, just retrieves existing
 200  *                      protection state without changing it.
 201  * @param set_flags     New flag values; only bits in set_mask are applied;
 202  *                      ignored if set_mask=0.
 203  * @param prot          Destination for updated protection state from EC.
 204  * @return 0 if ok, <0 on error
 205  */
 206 int cros_ec_flash_protect(struct cros_ec_dev *dev,
 207                        uint32_t set_mask, uint32_t set_flags,
 208                        struct ec_response_flash_protect *resp);
 209
 210
 211 /**
 212  * Run internal tests on the cros_ec interface.
 213  *
 214  * @param dev           CROS-EC device
 215  * @return 0 if ok, <0 if the test failed
 216  */
 217 int cros_ec_test(struct cros_ec_dev *dev);
 218
 219 /**
 220  * Update the EC RW copy.
 221  *
 222  * @param dev           CROS-EC device
 223  * @param image         the content to write
 224  * @param imafge_size   content length
 225  * @return 0 if ok, <0 if the test failed
 226  */
 227 int cros_ec_flash_update_rw(struct cros_ec_dev *dev,
 228                          const uint8_t  *image, int image_size);
 229
 230 /**
 231  * Return a pointer to the board's CROS-EC device
 232  *
 233  * This should be implemented by board files.
 234  *
 235  * @return pointer to CROS-EC device, or NULL if none is available
 236  */
 237 struct cros_ec_dev *board_get_cros_ec_dev(void);
 238
 239
 240 /* Internal interfaces */
 241 int cros_ec_i2c_init(struct cros_ec_dev *dev, const void *blob);
 242 int cros_ec_spi_init(struct cros_ec_dev *dev, const void *blob);
 243 int cros_ec_lpc_init(struct cros_ec_dev *dev, const void *blob);
 244
 245 /**
 246  * Read information from the fdt for the i2c cros_ec interface
 247  *
 248  * @param dev           CROS-EC device
 249  * @param blob          Device tree blob
 250  * @return 0 if ok, -1 if we failed to read all required information
 251  */
 252 int cros_ec_i2c_decode_fdt(struct cros_ec_dev *dev, const void *blob);
 253
 254 /**
 255  * Read information from the fdt for the spi cros_ec interface
 256  *
 257  * @param dev           CROS-EC device
 258  * @param blob          Device tree blob
 259  * @return 0 if ok, -1 if we failed to read all required information
 260  */
 261 int cros_ec_spi_decode_fdt(struct cros_ec_dev *dev, const void *blob);
 262
 263 /**
 264  * Check whether the LPC interface supports new-style commands.
 265  *
 266  * LPC has its own way of doing this, which involves checking LPC values
 267  * visible to the host. Do this, and update dev->cmd_version_is_supported
 268  * accordingly.
 269  *
 270  * @param dev           CROS-EC device to check
 271  */
 272 int cros_ec_lpc_check_version(struct cros_ec_dev *dev);
 273
 274 /**
 275  * Send a command to an I2C CROS-EC device and return the reply.
 276  *
 277  * This rather complicated function deals with sending both old-style and
 278  * new-style commands. The old ones have just a command byte and arguments.
 279  * The new ones have version, command, arg-len, [args], chksum so are 3 bytes
 280  * longer.
 281  *
 282  * The device's internal input/output buffers are used.
 283  *
 284  * @param dev           CROS-EC device
 285  * @param cmd           Command to send (EC_CMD_...)
 286  * @param cmd_version   Version of command to send (EC_VER_...)
 287  * @param dout          Output data (may be NULL If dout_len=0)
 288  * @param dout_len      Size of output data in bytes
 289  * @param dinp          Returns pointer to response data
 290  * @param din_len       Maximum size of response in bytes
 291  * @return number of bytes in response, or -1 on error
 292  */
 293 int cros_ec_i2c_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version,
 294                      const uint8_t *dout, int dout_len,
 295                      uint8_t **dinp, int din_len);
 296
 297 /**
 298  * Send a command to a LPC CROS-EC device and return the reply.
 299  *
 300  * The device's internal input/output buffers are used.
 301  *
 302  * @param dev           CROS-EC device
 303  * @param cmd           Command to send (EC_CMD_...)
 304  * @param cmd_version   Version of command to send (EC_VER_...)
 305  * @param dout          Output data (may be NULL If dout_len=0)
 306  * @param dout_len      Size of output data in bytes
 307  * @param dinp          Returns pointer to response data
 308  * @param din_len       Maximum size of response in bytes
 309  * @return number of bytes in response, or -1 on error
 310  */
 311 int cros_ec_lpc_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 int cros_ec_spi_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version,
 316                      const uint8_t *dout, int dout_len,
 317                      uint8_t **dinp, int din_len);
 318
 319 /**
 320  * Dump a block of data for a command.
 321  *
 322  * @param name  Name for data (e.g. 'in', 'out')
 323  * @param cmd   Command number associated with data, or -1 for none
 324  * @param data  Data block to dump
 325  * @param len   Length of data block to dump
 326  */
 327 void cros_ec_dump_data(const char *name, int cmd, const uint8_t *data, int len);
 328
 329 /**
 330  * Calculate a simple 8-bit checksum of a data block
 331  *
 332  * @param data  Data block to checksum
 333  * @param size  Size of data block in bytes
 334  * @return checksum value (0 to 255)
 335  */
 336 int cros_ec_calc_checksum(const uint8_t *data, int size);
 337
 338 /**
 339  * Decode a flash region parameter
 340  *
 341  * @param argc  Number of params remaining
 342  * @param argv  List of remaining parameters
 343  * @return flash region (EC_FLASH_REGION_...) or -1 on error
 344  */
 345 int cros_ec_decode_region(int argc, char * const argv[]);
 346
 347 int cros_ec_flash_erase(struct cros_ec_dev *dev, uint32_t offset,
 348                 uint32_t size);
 349
 350 /**
 351  * Read data from the flash
 352  *
 353  * Read an arbitrary amount of data from the EC flash, by repeatedly reading
 354  * small blocks.
 355  *
 356  * The offset starts at 0. You can obtain the region information from
 357  * cros_ec_flash_offset() to find out where to read for a particular region.
 358  *
 359  * @param dev           CROS-EC device
 360  * @param data          Pointer to data buffer to read into
 361  * @param offset        Offset within flash to read from
 362  * @param size          Number of bytes to read
 363  * @return 0 if ok, -1 on error
 364  */
 365 int cros_ec_flash_read(struct cros_ec_dev *dev, uint8_t *data, uint32_t offset,
 366                     uint32_t size);
 367
 368 /**
 369  * Write data to the flash
 370  *
 371  * Write an arbitrary amount of data to the EC flash, by repeatedly writing
 372  * small blocks.
 373  *
 374  * The offset starts at 0. You can obtain the region information from
 375  * cros_ec_flash_offset() to find out where to write for a particular region.
 376  *
 377  * Attempting to write to the region where the EC is currently running from
 378  * will result in an error.
 379  *
 380  * @param dev           CROS-EC device
 381  * @param data          Pointer to data buffer to write
 382  * @param offset        Offset within flash to write to.
 383  * @param size          Number of bytes to write
 384  * @return 0 if ok, -1 on error
 385  */
 386 int cros_ec_flash_write(struct cros_ec_dev *dev, const uint8_t *data,
 387                      uint32_t offset, uint32_t size);
 388
 389 /**
 390  * Obtain position and size of a flash region
 391  *
 392  * @param dev           CROS-EC device
 393  * @param region        Flash region to query
 394  * @param offset        Returns offset of flash region in EC flash
 395  * @param size          Returns size of flash region
 396  * @return 0 if ok, -1 on error
 397  */
 398 int cros_ec_flash_offset(struct cros_ec_dev *dev, enum ec_flash_region region,
 399                       uint32_t *offset, uint32_t *size);
 400
 401 /**
 402  * Read/write VbNvContext from/to a CROS-EC device.
 403  *
 404  * @param dev           CROS-EC device
 405  * @param block         Buffer of VbNvContext to be read/write
 406  * @return 0 if ok, -1 on error
 407  */
 408 int cros_ec_read_vbnvcontext(struct cros_ec_dev *dev, uint8_t *block);
 409 int cros_ec_write_vbnvcontext(struct cros_ec_dev *dev, const uint8_t *block);
 410
 411 /**
 412  * Read the version information for the EC images
 413  *
 414  * @param dev           CROS-EC device
 415  * @param versionp      This is set to point to the version information
 416  * @return 0 if ok, -1 on error
 417  */
 418 int cros_ec_read_version(struct cros_ec_dev *dev,
 419                        struct ec_response_get_version **versionp);
 420
 421 /**
 422  * Read the build information for the EC
 423  *
 424  * @param dev           CROS-EC device
 425  * @param versionp      This is set to point to the build string
 426  * @return 0 if ok, -1 on error
 427  */
 428 int cros_ec_read_build_info(struct cros_ec_dev *dev, char **strp);
 429
 430 /**
 431  * Switch on/off a LDO / FET.
 432  *
 433  * @param dev           CROS-EC device
 434  * @param index         index of the LDO/FET to switch
 435  * @param state         new state of the LDO/FET : EC_LDO_STATE_ON|OFF
 436  * @return 0 if ok, -1 on error
 437  */
 438 int cros_ec_set_ldo(struct cros_ec_dev *dev, uint8_t index, uint8_t state);
 439
 440 /**
 441  * Read back a LDO / FET current state.
 442  *
 443  * @param dev           CROS-EC device
 444  * @param index         index of the LDO/FET to switch
 445  * @param state         current state of the LDO/FET : EC_LDO_STATE_ON|OFF
 446  * @return 0 if ok, -1 on error
 447  */
 448 int cros_ec_get_ldo(struct cros_ec_dev *dev, uint8_t index, uint8_t *state);
 449 #endif