1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Chromium OS cros_ec driver
4  *
5  * Copyright (c) 2012 The Chromium OS Authors.
6  */
7 
8 #ifndef _CROS_EC_H
9 #define _CROS_EC_H
10 
11 #include <linux/compiler.h>
12 #include <ec_commands.h>
13 #include <cros_ec_message.h>
14 #include <asm/gpio.h>
15 #include <dm/of_extra.h>
16 
17 /* Our configuration information */
18 struct cros_ec_dev {
19 	struct udevice *dev;		/* Transport device */
20 	struct gpio_desc ec_int;	/* GPIO used as EC interrupt line */
21 	int protocol_version;           /* Protocol version to use */
22 	int optimise_flash_write;	/* Don't write erased flash blocks */
23 
24 	/*
25 	 * These two buffers will always be dword-aligned and include enough
26 	 * space for up to 7 word-alignment bytes also, so we can ensure that
27 	 * the body of the message is always dword-aligned (64-bit).
28 	 *
29 	 * We use this alignment to keep ARM and x86 happy. Probably word
30 	 * alignment would be OK, there might be a small performance advantage
31 	 * to using dword.
32 	 */
33 	uint8_t din[ALIGN(MSG_BYTES + sizeof(int64_t), sizeof(int64_t))]
34 		__aligned(sizeof(int64_t));
35 	uint8_t dout[ALIGN(MSG_BYTES + sizeof(int64_t), sizeof(int64_t))]
36 		__aligned(sizeof(int64_t));
37 };
38 
39 /*
40  * Hard-code the number of columns we happen to know we have right now.  It
41  * would be more correct to call cros_ec_info() at startup and determine the
42  * actual number of keyboard cols from there.
43  */
44 #define CROS_EC_KEYSCAN_COLS 13
45 
46 /* Information returned by a key scan */
47 struct mbkp_keyscan {
48 	uint8_t data[CROS_EC_KEYSCAN_COLS];
49 };
50 
51 /* Holds information about the Chrome EC */
52 struct fdt_cros_ec {
53 	struct fmap_entry flash;	/* Address and size of EC flash */
54 	/*
55 	 * Byte value of erased flash, or -1 if not known. It is normally
56 	 * 0xff but some flash devices use 0 (e.g. STM32Lxxx)
57 	 */
58 	int flash_erase_value;
59 	struct fmap_entry region[EC_FLASH_REGION_COUNT];
60 };
61 
62 /**
63  * Read the ID of the CROS-EC device
64  *
65  * The ID is a string identifying the CROS-EC device.
66  *
67  * @param dev		CROS-EC device
68  * @param id		Place to put the ID
69  * @param maxlen	Maximum length of the ID field
70  * @return 0 if ok, -1 on error
71  */
72 int cros_ec_read_id(struct udevice *dev, char *id, int maxlen);
73 
74 /**
75  * Read a keyboard scan from the CROS-EC device
76  *
77  * Send a message requesting a keyboard scan and return the result
78  *
79  * @param dev		CROS-EC device
80  * @param scan		Place to put the scan results
81  * @return 0 if ok, -1 on error
82  */
83 int cros_ec_scan_keyboard(struct udevice *dev, struct mbkp_keyscan *scan);
84 
85 /**
86  * Get the next pending MKBP event from the ChromeOS EC device.
87  *
88  * Send a message requesting the next event and return the result.
89  *
90  * @param event		Place to put the event.
91  * @return 0 if ok, <0 on error.
92  */
93 int cros_ec_get_next_event(struct udevice *dev,
94 			   struct ec_response_get_next_event *event);
95 
96 /**
97  * Read which image is currently running on the CROS-EC device.
98  *
99  * @param dev		CROS-EC device
100  * @param image		Destination for image identifier
101  * @return 0 if ok, <0 on error
102  */
103 int cros_ec_read_current_image(struct udevice *dev,
104 			       enum ec_current_image *image);
105 
106 /**
107  * Read the hash of the CROS-EC device firmware.
108  *
109  * @param dev		CROS-EC device
110  * @param hash_offset	Offset in flash to read from
111  * @param hash		Destination for hash information
112  * @return 0 if ok, <0 on error
113  */
114 int cros_ec_read_hash(struct udevice *dev, uint hash_offset,
115 		      struct ec_response_vboot_hash *hash);
116 
117 /**
118  * Send a reboot command to the CROS-EC device.
119  *
120  * Note that some reboot commands (such as EC_REBOOT_COLD) also reboot the AP.
121  *
122  * @param dev		CROS-EC device
123  * @param cmd		Reboot command
124  * @param flags         Flags for reboot command (EC_REBOOT_FLAG_*)
125  * @return 0 if ok, <0 on error
126  */
127 int cros_ec_reboot(struct udevice *dev, enum ec_reboot_cmd cmd, uint8_t flags);
128 
129 /**
130  * Check if the CROS-EC device has an interrupt pending.
131  *
132  * Read the status of the external interrupt connected to the CROS-EC device.
133  * If no external interrupt is configured, this always returns 1.
134  *
135  * @param dev		CROS-EC device
136  * @return 0 if no interrupt is pending
137  */
138 int cros_ec_interrupt_pending(struct udevice *dev);
139 
140 enum {
141 	CROS_EC_OK,
142 	CROS_EC_ERR = 1,
143 	CROS_EC_ERR_FDT_DECODE,
144 	CROS_EC_ERR_CHECK_VERSION,
145 	CROS_EC_ERR_READ_ID,
146 	CROS_EC_ERR_DEV_INIT,
147 };
148 
149 /**
150  * Initialise the Chromium OS EC driver
151  *
152  * @param blob		Device tree blob containing setup information
153  * @param cros_ecp        Returns pointer to the cros_ec device, or NULL if none
154  * @return 0 if we got an cros_ec device and all is well (or no cros_ec is
155  *	expected), -ve if we should have an cros_ec device but failed to find
156  *	one, or init failed (-CROS_EC_ERR_...).
157  */
158 int cros_ec_init(const void *blob, struct udevice**cros_ecp);
159 
160 /**
161  * Read information about the keyboard matrix
162  *
163  * @param dev		CROS-EC device
164  * @param info		Place to put the info structure
165  */
166 int cros_ec_info(struct udevice *dev, struct ec_response_mkbp_info *info);
167 
168 /**
169  * Read the host event flags
170  *
171  * @param dev		CROS-EC device
172  * @param events_ptr	Destination for event flags.  Not changed on error.
173  * @return 0 if ok, <0 on error
174  */
175 int cros_ec_get_host_events(struct udevice *dev, uint32_t *events_ptr);
176 
177 /**
178  * Clear the specified host event flags
179  *
180  * @param dev		CROS-EC device
181  * @param events	Event flags to clear
182  * @return 0 if ok, <0 on error
183  */
184 int cros_ec_clear_host_events(struct udevice *dev, uint32_t events);
185 
186 /**
187  * Get/set flash protection
188  *
189  * @param dev		CROS-EC device
190  * @param set_mask	Mask of flags to set; if 0, just retrieves existing
191  *                      protection state without changing it.
192  * @param set_flags	New flag values; only bits in set_mask are applied;
193  *                      ignored if set_mask=0.
194  * @param prot          Destination for updated protection state from EC.
195  * @return 0 if ok, <0 on error
196  */
197 int cros_ec_flash_protect(struct udevice *dev, uint32_t set_mask,
198 			  uint32_t set_flags,
199 			  struct ec_response_flash_protect *resp);
200 
201 /**
202  * Notify EC of current boot mode
203  *
204  * @param dev		CROS-EC device
205  * @param vboot_mode    Verified boot mode
206  * @return 0 if ok, <0 on error
207  */
208 int cros_ec_entering_mode(struct udevice *dev, int mode);
209 
210 /**
211  * Run internal tests on the cros_ec interface.
212  *
213  * @param dev		CROS-EC device
214  * @return 0 if ok, <0 if the test failed
215  */
216 int cros_ec_test(struct udevice *dev);
217 
218 /**
219  * Update the EC RW copy.
220  *
221  * @param dev		CROS-EC device
222  * @param image		the content to write
223  * @param imafge_size	content length
224  * @return 0 if ok, <0 if the test failed
225  */
226 int cros_ec_flash_update_rw(struct udevice *dev, const uint8_t  *image,
227 			    int image_size);
228 
229 /**
230  * Return a pointer to the board's CROS-EC device
231  *
232  * @return pointer to CROS-EC device, or NULL if none is available
233  */
234 struct udevice *board_get_cros_ec_dev(void);
235 
236 struct dm_cros_ec_ops {
237 	/**
238 	 * check_version() - Check the protocol version being used (optional)
239 	 *
240 	 * If provided, this function should check that the EC can be supported
241 	 * by the driver. If not provided, HELLO messages will be sent to try
242 	 * to determine the protocol version.
243 	 *
244 	 * @dev: Device to check
245 	 * @return 0 if the protocol is valid, -ve if not supported
246 	 */
247 	int (*check_version)(struct udevice *dev);
248 
249 	/**
250 	 * command() - Old-style command interface
251 	 *
252 	 * This sends a command and receives a response (deprecated, use
253 	 * packet())
254 	 *
255 	 * @dev: Device to use
256 	 * @cmd: Command to send (only supports 0-0xff)
257 	 * @cmd_version: Version of command to send (often 0)
258 	 * @dout: Output data (may be NULL If dout_len=0)
259 	 * @dout_len: Length of output data excluding 4-byte header
260 	 * @dinp: On input, set to point to input data, often struct
261 	 *	cros_ec_dev->din - typically this is left alone but may be
262 	 *	updated by the driver
263 	 * @din_len: Maximum length of response
264 	 * @return number of bytes in response, or -ve on error
265 	 */
266 	int (*command)(struct udevice *dev, uint8_t cmd, int cmd_version,
267 		       const uint8_t *dout, int dout_len,
268 		       uint8_t **dinp, int din_len);
269 
270 	/**
271 	 * packet() - New-style command interface
272 	 *
273 	 * This interface is preferred over command(), since it is typically
274 	 * easier to implement.
275 	 *
276 	 * @dev: Device to use
277 	 * @out_bytes: Number of bytes to send (from struct cros_ec_dev->dout)
278 	 * @in_bytes: Maximum number of bytes to expect in response
279 	 * @return number of bytes in response, or -ve on error
280 	 */
281 	int (*packet)(struct udevice *dev, int out_bytes, int in_bytes);
282 
283 	/**
284 	 * get_switches() - Get value of EC switches
285 	 *
286 	 * This is currently supported on the LPC EC.
287 	 *
288 	 * @dev: Device to use
289 	 * @return current switches value, or -ENOSYS if not supported
290 	 */
291 	int (*get_switches)(struct udevice *dev);
292 };
293 
294 #define dm_cros_ec_get_ops(dev) \
295 		((struct dm_cros_ec_ops *)(dev)->driver->ops)
296 
297 int cros_ec_register(struct udevice *dev);
298 
299 /**
300  * Dump a block of data for a command.
301  *
302  * @param name	Name for data (e.g. 'in', 'out')
303  * @param cmd	Command number associated with data, or -1 for none
304  * @param data	Data block to dump
305  * @param len	Length of data block to dump
306  */
307 void cros_ec_dump_data(const char *name, int cmd, const uint8_t *data, int len);
308 
309 /**
310  * Calculate a simple 8-bit checksum of a data block
311  *
312  * @param data	Data block to checksum
313  * @param size	Size of data block in bytes
314  * @return checksum value (0 to 255)
315  */
316 int cros_ec_calc_checksum(const uint8_t *data, int size);
317 
318 int cros_ec_flash_erase(struct udevice *dev, uint32_t offset, uint32_t size);
319 
320 /**
321  * Read data from the flash
322  *
323  * Read an arbitrary amount of data from the EC flash, by repeatedly reading
324  * small blocks.
325  *
326  * The offset starts at 0. You can obtain the region information from
327  * cros_ec_flash_offset() to find out where to read for a particular region.
328  *
329  * @param dev		CROS-EC device
330  * @param data		Pointer to data buffer to read into
331  * @param offset	Offset within flash to read from
332  * @param size		Number of bytes to read
333  * @return 0 if ok, -1 on error
334  */
335 int cros_ec_flash_read(struct udevice *dev, uint8_t *data, uint32_t offset,
336 		       uint32_t size);
337 
338 /**
339  * Read back flash parameters
340  *
341  * This function reads back parameters of the flash as reported by the EC
342  *
343  * @param dev  Pointer to device
344  * @param info Pointer to output flash info struct
345  */
346 int cros_ec_read_flashinfo(struct udevice *dev,
347 			   struct ec_response_flash_info *info);
348 
349 /**
350  * Write data to the flash
351  *
352  * Write an arbitrary amount of data to the EC flash, by repeatedly writing
353  * small blocks.
354  *
355  * The offset starts at 0. You can obtain the region information from
356  * cros_ec_flash_offset() to find out where to write for a particular region.
357  *
358  * Attempting to write to the region where the EC is currently running from
359  * will result in an error.
360  *
361  * @param dev		CROS-EC device
362  * @param data		Pointer to data buffer to write
363  * @param offset	Offset within flash to write to.
364  * @param size		Number of bytes to write
365  * @return 0 if ok, -1 on error
366  */
367 int cros_ec_flash_write(struct udevice *dev, const uint8_t *data,
368 			uint32_t offset, uint32_t size);
369 
370 /**
371  * Obtain position and size of a flash region
372  *
373  * @param dev		CROS-EC device
374  * @param region	Flash region to query
375  * @param offset	Returns offset of flash region in EC flash
376  * @param size		Returns size of flash region
377  * @return 0 if ok, -1 on error
378  */
379 int cros_ec_flash_offset(struct udevice *dev, enum ec_flash_region region,
380 			 uint32_t *offset, uint32_t *size);
381 
382 /**
383  * cros_ec_get_sku_id() - Read the SKU ID
384  *
385  * @dev: CROS-EC device
386  * return SKU ID, or -ve on error
387  */
388 int cros_ec_get_sku_id(struct udevice *dev);
389 
390 /**
391  * Read/write non-volatile data from/to a CROS-EC device.
392  *
393  * @param dev		CROS-EC device
394  * @param block		Buffer of VbNvContext to be read/write
395  * @return 0 if ok, -1 on error
396  */
397 int cros_ec_read_nvdata(struct udevice *dev, uint8_t *block, int size);
398 int cros_ec_write_nvdata(struct udevice *dev, const uint8_t *block, int size);
399 
400 /**
401  * Read the version information for the EC images
402  *
403  * @param dev		CROS-EC device
404  * @param versionp	This is set to point to the version information
405  * @return 0 if ok, -1 on error
406  */
407 int cros_ec_read_version(struct udevice *dev,
408 			 struct ec_response_get_version **versionp);
409 
410 /**
411  * Read the build information for the EC
412  *
413  * @param dev		CROS-EC device
414  * @param versionp	This is set to point to the build string
415  * @return 0 if ok, -1 on error
416  */
417 int cros_ec_read_build_info(struct udevice *dev, char **strp);
418 
419 /**
420  * Switch on/off a LDO / FET.
421  *
422  * @param dev		CROS-EC device
423  * @param index		index of the LDO/FET to switch
424  * @param state		new state of the LDO/FET : EC_LDO_STATE_ON|OFF
425  * @return 0 if ok, -1 on error
426  */
427 int cros_ec_set_ldo(struct udevice *dev, uint8_t index, uint8_t state);
428 
429 /**
430  * Read back a LDO / FET current state.
431  *
432  * @param dev		CROS-EC device
433  * @param index		index of the LDO/FET to switch
434  * @param state		current state of the LDO/FET : EC_LDO_STATE_ON|OFF
435  * @return 0 if ok, -1 on error
436  */
437 int cros_ec_get_ldo(struct udevice *dev, uint8_t index, uint8_t *state);
438 
439 /**
440  * Get access to the error reported when cros_ec_board_init() was called
441  *
442  * This permits delayed reporting of the EC error if it failed during
443  * early init.
444  *
445  * @return error (0 if there was no error, -ve if there was an error)
446  */
447 int cros_ec_get_error(void);
448 
449 /**
450  * Returns information from the FDT about the Chrome EC flash
451  *
452  * @param dev		Device to read from
453  * @param config	Structure to use to return information
454  */
455 int cros_ec_decode_ec_flash(struct udevice *dev, struct fdt_cros_ec *config);
456 
457 /**
458  * Check the current keyboard state, in case recovery mode is requested.
459  * This function is for sandbox only.
460  *
461  * @param ec		CROS-EC device
462  */
463 void cros_ec_check_keyboard(struct udevice *dev);
464 
465 struct i2c_msg;
466 /*
467  * Tunnel an I2C transfer to the EC
468  *
469  * @param dev		CROS-EC device
470  * @param port		The remote port on EC to use
471  * @param msg		List of messages to transfer
472  * @param nmsgs		Number of messages to transfer
473  */
474 int cros_ec_i2c_tunnel(struct udevice *dev, int port, struct i2c_msg *msg,
475 		       int nmsgs);
476 
477 /**
478  * cros_ec_get_events_b() - Get event mask B
479  *
480  * @return value of event mask, default value of 0 if it could not be read
481  */
482 uint64_t cros_ec_get_events_b(struct udevice *dev);
483 
484 /**
485  * cros_ec_clear_events_b() - Clear even mask B
486  *
487  * Any pending events in the B range are cleared
488  *
489  * @return 0 if OK, -ve on error
490  */
491 int cros_ec_clear_events_b(struct udevice *dev, uint64_t mask);
492 
493 /**
494  * cros_ec_efs_verify() - tell the EC to verify one of its images
495  *
496  * @param dev		CROS-EC device
497  * @param region	Flash region to query
498  * @return 0 if OK, -ve on error
499  */
500 int cros_ec_efs_verify(struct udevice *dev, enum ec_flash_region region);
501 
502 /**
503  * cros_ec_battery_cutoff() - Request that the battery be cut off
504  *
505  * This tells the battery to stop supplying power. This is used before shipping
506  * a device to ensure that the battery remains charged while the device is
507  * shipped or sitting on the shelf waiting to be purchased.
508  *
509  * @param dev		CROS-EC device
510  * @param flags		Flags to use (EC_BATTERY_CUTOFF_FLAG_...)
511  * @return 0 if OK, -ve on error
512  */
513 int cros_ec_battery_cutoff(struct udevice *dev, uint8_t flags);
514 
515 /**
516  * cros_ec_read_limit_power() - Check if power is limited by batter/charger
517  *
518  * Sometimes the battery is low and / or the device is connected to a charger
519  * that cannot supply much power.
520  *
521  * @param dev		CROS-EC device
522  * @param limit_powerp	Returns whether power is limited (0 or 1)
523  * @return 0 if OK, -ENOSYS if the EC does not support this comment, -EINVAL
524  *		if the EC returned an invalid response
525  */
526 int cros_ec_read_limit_power(struct udevice *dev, int *limit_powerp);
527 
528 /**
529  * cros_ec_config_powerbtn() - Configure the behaviour of the power button
530  *
531  * @param dev		CROS-EC device
532  * @param flags		Flags to use (EC_POWER_BUTTON_...)
533  * @return 0 if OK, -ve on error
534  */
535 int cros_ec_config_powerbtn(struct udevice *dev, uint32_t flags);
536 
537 /**
538  * cros_ec_get_lid_shutdown_mask() - Set the lid shutdown mask
539  *
540  * Determines whether a lid close event is reported
541  *
542  * @param dev		CROS-EC device
543  * @return shufdown mas if OK, -ve on error
544  */
545 int cros_ec_get_lid_shutdown_mask(struct udevice *dev);
546 
547 /**
548  * cros_ec_set_lid_shutdown_mask() - Set the lid shutdown mask
549  *
550  * Set whether a lid close event is reported
551  *
552  * @param dev		CROS-EC device
553  * @param enable	true to enable reporting, false to disable
554  * @return shufdown mas if OK, -ve on error
555  */
556 int cros_ec_set_lid_shutdown_mask(struct udevice *dev, int enable);
557 
558 /**
559  * cros_ec_hello() - Send a hello message
560  *
561  * Sends a message with a fixed input value and checks that the expected output
562  * value is received
563  *
564  * @dev: CROS-EC device
565  * @handshakep: If non-NULL, returns received handshake value on error
566  * @return 0 if OK, -ve on error
567  */
568 int cros_ec_hello(struct udevice *dev, uint *handshakep);
569 
570 /**
571  * cros_ec_get_features() - Get the set of features provided by the EC
572  *
573  * See enum ec_feature_code for the list of available features
574  *
575  * @dev: CROS-EC device
576  * @featuresp: Returns a bitmask of supported features
577  * @return 0 if OK, -ve on error
578  */
579 int cros_ec_get_features(struct udevice *dev, u64 *featuresp);
580 
581 /**
582  * cros_ec_check_feature() - Check if a feature is supported
583  *
584  * @dev: CROS-EC device
585  * @feature: Feature number to check (enum ec_feature_code)
586  * @return true if supported, false if not, -ve on error
587  */
588 int cros_ec_check_feature(struct udevice *dev, uint feature);
589 
590 /**
591  * cros_ec_get_switches() - Get switches value
592  *
593  * @dev: CROS-EC device
594  * @return switches value, or -ENOSYS if not supported, or other -ve value on
595  *	other error
596  */
597 int cros_ec_get_switches(struct udevice *dev);
598 
599 /**
600  * cros_ec_vstore_supported() - Check if vstore is supported
601  *
602  * @dev: CROS-EC device
603  * @return false if not supported, true if supported, -ve on error
604  */
605 int cros_ec_vstore_supported(struct udevice *dev);
606 
607 /**
608  * cros_ec_vstore_info() - Get vstore information
609  *
610  * @dev: CROS-EC device
611  * @lockedp: mask of locked slots
612  * @return number of vstore slots supported by the EC,, -ve on error
613  */
614 int cros_ec_vstore_info(struct udevice *dev, u32 *lockedp);
615 
616 /**
617  * cros_ec_vstore_read() - Read data from EC vstore slot
618  *
619  * @dev: CROS-EC device
620  * @slot: vstore slot to read from
621  * @data: buffer to store read data, must be EC_VSTORE_SLOT_SIZE bytes
622  * @return 0 if OK, -ve on error
623  */
624 int cros_ec_vstore_read(struct udevice *dev, int slot, uint8_t *data);
625 
626 /**
627  * cros_ec_vstore_write() - Save data into EC vstore slot
628  *
629  * The maximum size of data is EC_VSTORE_SLOT_SIZE.  It is the caller's
630  * responsibility to check the number of implemented slots by querying the
631  * vstore info.
632  *
633  * @dev: CROS-EC device
634  * @slot: vstore slot to write into
635  * @data: data to write
636  * @size: size of data in bytes
637  * @return 0 if OK, -ve on error
638  */
639 int cros_ec_vstore_write(struct udevice *dev, int slot, const uint8_t *data,
640 			 size_t size);
641 
642 #endif
643