xref: /linux/drivers/input/keyboard/cros_ec_keyb.c (revision 7ec462100ef9142344ddbf86f2c3008b97acddbe)
1 // SPDX-License-Identifier: GPL-2.0
2 // ChromeOS EC keyboard driver
3 //
4 // Copyright (C) 2012 Google, Inc.
5 //
6 // This driver uses the ChromeOS EC byte-level message-based protocol for
7 // communicating the keyboard state (which keys are pressed) from a keyboard EC
8 // to the AP over some bus (such as i2c, lpc, spi).  The EC does debouncing,
9 // but everything else (including deghosting) is done here.  The main
10 // motivation for this is to keep the EC firmware as simple as possible, since
11 // it cannot be easily upgraded and EC flash/IRAM space is relatively
12 // expensive.
13 
14 #include <linux/module.h>
15 #include <linux/acpi.h>
16 #include <linux/bitops.h>
17 #include <linux/i2c.h>
18 #include <linux/input.h>
19 #include <linux/input/vivaldi-fmap.h>
20 #include <linux/interrupt.h>
21 #include <linux/kernel.h>
22 #include <linux/notifier.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include <linux/sysrq.h>
26 #include <linux/input/matrix_keypad.h>
27 #include <linux/platform_data/cros_ec_commands.h>
28 #include <linux/platform_data/cros_ec_proto.h>
29 
30 #include <linux/unaligned.h>
31 
32 /**
33  * struct cros_ec_keyb - Structure representing EC keyboard device
34  *
35  * @rows: Number of rows in the keypad
36  * @cols: Number of columns in the keypad
37  * @row_shift: log2 or number of rows, rounded up
38  * @ghost_filter: true to enable the matrix key-ghosting filter
39  * @valid_keys: bitmap of existing keys for each matrix column
40  * @old_kb_state: bitmap of keys pressed last scan
41  * @dev: Device pointer
42  * @ec: Top level ChromeOS device to use to talk to EC
43  * @idev: The input device for the matrix keys.
44  * @bs_idev: The input device for non-matrix buttons and switches (or NULL).
45  * @notifier: interrupt event notifier for transport devices
46  * @vdata: vivaldi function row data
47  */
48 struct cros_ec_keyb {
49 	unsigned int rows;
50 	unsigned int cols;
51 	int row_shift;
52 	bool ghost_filter;
53 	uint8_t *valid_keys;
54 	uint8_t *old_kb_state;
55 
56 	struct device *dev;
57 	struct cros_ec_device *ec;
58 
59 	struct input_dev *idev;
60 	struct input_dev *bs_idev;
61 	struct notifier_block notifier;
62 
63 	struct vivaldi_data vdata;
64 };
65 
66 /**
67  * struct cros_ec_bs_map - Mapping between Linux keycodes and EC button/switch
68  *	bitmap #defines
69  *
70  * @ev_type: The type of the input event to generate (e.g., EV_KEY).
71  * @code: A linux keycode
72  * @bit: A #define like EC_MKBP_POWER_BUTTON or EC_MKBP_LID_OPEN
73  * @inverted: If the #define and EV_SW have opposite meanings, this is true.
74  *            Only applicable to switches.
75  */
76 struct cros_ec_bs_map {
77 	unsigned int ev_type;
78 	unsigned int code;
79 	u8 bit;
80 	bool inverted;
81 };
82 
83 /* cros_ec_keyb_bs - Map EC button/switch #defines into kernel ones */
84 static const struct cros_ec_bs_map cros_ec_keyb_bs[] = {
85 	/* Buttons */
86 	{
87 		.ev_type	= EV_KEY,
88 		.code		= KEY_POWER,
89 		.bit		= EC_MKBP_POWER_BUTTON,
90 	},
91 	{
92 		.ev_type	= EV_KEY,
93 		.code		= KEY_VOLUMEUP,
94 		.bit		= EC_MKBP_VOL_UP,
95 	},
96 	{
97 		.ev_type	= EV_KEY,
98 		.code		= KEY_VOLUMEDOWN,
99 		.bit		= EC_MKBP_VOL_DOWN,
100 	},
101 	{
102 		.ev_type        = EV_KEY,
103 		.code           = KEY_BRIGHTNESSUP,
104 		.bit            = EC_MKBP_BRI_UP,
105 	},
106 	{
107 		.ev_type        = EV_KEY,
108 		.code           = KEY_BRIGHTNESSDOWN,
109 		.bit            = EC_MKBP_BRI_DOWN,
110 	},
111 	{
112 		.ev_type        = EV_KEY,
113 		.code           = KEY_SCREENLOCK,
114 		.bit            = EC_MKBP_SCREEN_LOCK,
115 	},
116 
117 	/* Switches */
118 	{
119 		.ev_type	= EV_SW,
120 		.code		= SW_LID,
121 		.bit		= EC_MKBP_LID_OPEN,
122 		.inverted	= true,
123 	},
124 	{
125 		.ev_type	= EV_SW,
126 		.code		= SW_TABLET_MODE,
127 		.bit		= EC_MKBP_TABLET_MODE,
128 	},
129 };
130 
131 /*
132  * Returns true when there is at least one combination of pressed keys that
133  * results in ghosting.
134  */
cros_ec_keyb_has_ghosting(struct cros_ec_keyb * ckdev,uint8_t * buf)135 static bool cros_ec_keyb_has_ghosting(struct cros_ec_keyb *ckdev, uint8_t *buf)
136 {
137 	int col1, col2, buf1, buf2;
138 	struct device *dev = ckdev->dev;
139 	uint8_t *valid_keys = ckdev->valid_keys;
140 
141 	/*
142 	 * Ghosting happens if for any pressed key X there are other keys
143 	 * pressed both in the same row and column of X as, for instance,
144 	 * in the following diagram:
145 	 *
146 	 * . . Y . g .
147 	 * . . . . . .
148 	 * . . . . . .
149 	 * . . X . Z .
150 	 *
151 	 * In this case only X, Y, and Z are pressed, but g appears to be
152 	 * pressed too (see Wikipedia).
153 	 */
154 	for (col1 = 0; col1 < ckdev->cols; col1++) {
155 		buf1 = buf[col1] & valid_keys[col1];
156 		for (col2 = col1 + 1; col2 < ckdev->cols; col2++) {
157 			buf2 = buf[col2] & valid_keys[col2];
158 			if (hweight8(buf1 & buf2) > 1) {
159 				dev_dbg(dev, "ghost found at: B[%02d]:0x%02x & B[%02d]:0x%02x",
160 					col1, buf1, col2, buf2);
161 				return true;
162 			}
163 		}
164 	}
165 
166 	return false;
167 }
168 
169 
170 /*
171  * Compares the new keyboard state to the old one and produces key
172  * press/release events accordingly.  The keyboard state is 13 bytes (one byte
173  * per column)
174  */
cros_ec_keyb_process(struct cros_ec_keyb * ckdev,uint8_t * kb_state,int len)175 static void cros_ec_keyb_process(struct cros_ec_keyb *ckdev,
176 			 uint8_t *kb_state, int len)
177 {
178 	struct input_dev *idev = ckdev->idev;
179 	int col, row;
180 	int new_state;
181 	int old_state;
182 
183 	if (ckdev->ghost_filter && cros_ec_keyb_has_ghosting(ckdev, kb_state)) {
184 		/*
185 		 * Simple-minded solution: ignore this state. The obvious
186 		 * improvement is to only ignore changes to keys involved in
187 		 * the ghosting, but process the other changes.
188 		 */
189 		dev_dbg(ckdev->dev, "ghosting found\n");
190 		return;
191 	}
192 
193 	for (col = 0; col < ckdev->cols; col++) {
194 		for (row = 0; row < ckdev->rows; row++) {
195 			int pos = MATRIX_SCAN_CODE(row, col, ckdev->row_shift);
196 			const unsigned short *keycodes = idev->keycode;
197 
198 			new_state = kb_state[col] & (1 << row);
199 			old_state = ckdev->old_kb_state[col] & (1 << row);
200 			if (new_state != old_state) {
201 				dev_dbg(ckdev->dev,
202 					"changed: [r%d c%d]: byte %02x\n",
203 					row, col, new_state);
204 
205 				input_event(idev, EV_MSC, MSC_SCAN, pos);
206 				input_report_key(idev, keycodes[pos],
207 						 new_state);
208 			}
209 		}
210 		ckdev->old_kb_state[col] = kb_state[col];
211 	}
212 	input_sync(ckdev->idev);
213 }
214 
215 /**
216  * cros_ec_keyb_report_bs - Report non-matrixed buttons or switches
217  *
218  * This takes a bitmap of buttons or switches from the EC and reports events,
219  * syncing at the end.
220  *
221  * @ckdev: The keyboard device.
222  * @ev_type: The input event type (e.g., EV_KEY).
223  * @mask: A bitmap of buttons from the EC.
224  */
cros_ec_keyb_report_bs(struct cros_ec_keyb * ckdev,unsigned int ev_type,u32 mask)225 static void cros_ec_keyb_report_bs(struct cros_ec_keyb *ckdev,
226 				   unsigned int ev_type, u32 mask)
227 
228 {
229 	struct input_dev *idev = ckdev->bs_idev;
230 	int i;
231 
232 	for (i = 0; i < ARRAY_SIZE(cros_ec_keyb_bs); i++) {
233 		const struct cros_ec_bs_map *map = &cros_ec_keyb_bs[i];
234 
235 		if (map->ev_type != ev_type)
236 			continue;
237 
238 		input_event(idev, ev_type, map->code,
239 			    !!(mask & BIT(map->bit)) ^ map->inverted);
240 	}
241 	input_sync(idev);
242 }
243 
cros_ec_keyb_work(struct notifier_block * nb,unsigned long queued_during_suspend,void * _notify)244 static int cros_ec_keyb_work(struct notifier_block *nb,
245 			     unsigned long queued_during_suspend, void *_notify)
246 {
247 	struct cros_ec_keyb *ckdev = container_of(nb, struct cros_ec_keyb,
248 						  notifier);
249 	u32 val;
250 	unsigned int ev_type;
251 
252 	/*
253 	 * If not wake enabled, discard key state changes during
254 	 * suspend. Switches will be re-checked in
255 	 * cros_ec_keyb_resume() to be sure nothing is lost.
256 	 */
257 	if (queued_during_suspend && !device_may_wakeup(ckdev->dev))
258 		return NOTIFY_OK;
259 
260 	switch (ckdev->ec->event_data.event_type) {
261 	case EC_MKBP_EVENT_KEY_MATRIX:
262 		pm_wakeup_event(ckdev->dev, 0);
263 
264 		if (ckdev->ec->event_size != ckdev->cols) {
265 			dev_err(ckdev->dev,
266 				"Discarded incomplete key matrix event.\n");
267 			return NOTIFY_OK;
268 		}
269 
270 		cros_ec_keyb_process(ckdev,
271 				     ckdev->ec->event_data.data.key_matrix,
272 				     ckdev->ec->event_size);
273 		break;
274 
275 	case EC_MKBP_EVENT_SYSRQ:
276 		pm_wakeup_event(ckdev->dev, 0);
277 
278 		val = get_unaligned_le32(&ckdev->ec->event_data.data.sysrq);
279 		dev_dbg(ckdev->dev, "sysrq code from EC: %#x\n", val);
280 		handle_sysrq(val);
281 		break;
282 
283 	case EC_MKBP_EVENT_BUTTON:
284 	case EC_MKBP_EVENT_SWITCH:
285 		pm_wakeup_event(ckdev->dev, 0);
286 
287 		if (ckdev->ec->event_data.event_type == EC_MKBP_EVENT_BUTTON) {
288 			val = get_unaligned_le32(
289 					&ckdev->ec->event_data.data.buttons);
290 			ev_type = EV_KEY;
291 		} else {
292 			val = get_unaligned_le32(
293 					&ckdev->ec->event_data.data.switches);
294 			ev_type = EV_SW;
295 		}
296 		cros_ec_keyb_report_bs(ckdev, ev_type, val);
297 		break;
298 
299 	default:
300 		return NOTIFY_DONE;
301 	}
302 
303 	return NOTIFY_OK;
304 }
305 
306 /*
307  * Walks keycodes flipping bit in buffer COLUMNS deep where bit is ROW.  Used by
308  * ghosting logic to ignore NULL or virtual keys.
309  */
cros_ec_keyb_compute_valid_keys(struct cros_ec_keyb * ckdev)310 static void cros_ec_keyb_compute_valid_keys(struct cros_ec_keyb *ckdev)
311 {
312 	int row, col;
313 	int row_shift = ckdev->row_shift;
314 	unsigned short *keymap = ckdev->idev->keycode;
315 	unsigned short code;
316 
317 	BUG_ON(ckdev->idev->keycodesize != sizeof(*keymap));
318 
319 	for (col = 0; col < ckdev->cols; col++) {
320 		for (row = 0; row < ckdev->rows; row++) {
321 			code = keymap[MATRIX_SCAN_CODE(row, col, row_shift)];
322 			if (code && (code != KEY_BATTERY))
323 				ckdev->valid_keys[col] |= 1 << row;
324 		}
325 		dev_dbg(ckdev->dev, "valid_keys[%02d] = 0x%02x\n",
326 			col, ckdev->valid_keys[col]);
327 	}
328 }
329 
330 /**
331  * cros_ec_keyb_info - Wrap the EC command EC_CMD_MKBP_INFO
332  *
333  * This wraps the EC_CMD_MKBP_INFO, abstracting out all of the marshalling and
334  * unmarshalling and different version nonsense into something simple.
335  *
336  * @ec_dev: The EC device
337  * @info_type: Either EC_MKBP_INFO_SUPPORTED or EC_MKBP_INFO_CURRENT.
338  * @event_type: Either EC_MKBP_EVENT_BUTTON or EC_MKBP_EVENT_SWITCH.  Actually
339  *              in some cases this could be EC_MKBP_EVENT_KEY_MATRIX or
340  *              EC_MKBP_EVENT_HOST_EVENT too but we don't use in this driver.
341  * @result: Where we'll store the result; a union
342  * @result_size: The size of the result.  Expected to be the size of one of
343  *               the elements in the union.
344  *
345  * Returns 0 if no error or -error upon error.
346  */
cros_ec_keyb_info(struct cros_ec_device * ec_dev,enum ec_mkbp_info_type info_type,enum ec_mkbp_event event_type,union ec_response_get_next_data * result,size_t result_size)347 static int cros_ec_keyb_info(struct cros_ec_device *ec_dev,
348 			     enum ec_mkbp_info_type info_type,
349 			     enum ec_mkbp_event event_type,
350 			     union ec_response_get_next_data *result,
351 			     size_t result_size)
352 {
353 	struct ec_params_mkbp_info *params;
354 	struct cros_ec_command *msg;
355 	int ret;
356 
357 	msg = kzalloc(sizeof(*msg) + max_t(size_t, result_size,
358 					   sizeof(*params)), GFP_KERNEL);
359 	if (!msg)
360 		return -ENOMEM;
361 
362 	msg->command = EC_CMD_MKBP_INFO;
363 	msg->version = 1;
364 	msg->outsize = sizeof(*params);
365 	msg->insize = result_size;
366 	params = (struct ec_params_mkbp_info *)msg->data;
367 	params->info_type = info_type;
368 	params->event_type = event_type;
369 
370 	ret = cros_ec_cmd_xfer_status(ec_dev, msg);
371 	if (ret == -ENOPROTOOPT) {
372 		/* With older ECs we just return 0 for everything */
373 		memset(result, 0, result_size);
374 		ret = 0;
375 	} else if (ret < 0) {
376 		dev_warn(ec_dev->dev, "Transfer error %d/%d: %d\n",
377 			 (int)info_type, (int)event_type, ret);
378 	} else if (ret != result_size) {
379 		dev_warn(ec_dev->dev, "Wrong size %d/%d: %d != %zu\n",
380 			 (int)info_type, (int)event_type,
381 			 ret, result_size);
382 		ret = -EPROTO;
383 	} else {
384 		memcpy(result, msg->data, result_size);
385 		ret = 0;
386 	}
387 
388 	kfree(msg);
389 
390 	return ret;
391 }
392 
393 /**
394  * cros_ec_keyb_query_switches - Query the state of switches and report
395  *
396  * This will ask the EC about the current state of switches and report to the
397  * kernel.  Note that we don't query for buttons because they are more
398  * transitory and we'll get an update on the next release / press.
399  *
400  * @ckdev: The keyboard device
401  *
402  * Returns 0 if no error or -error upon error.
403  */
cros_ec_keyb_query_switches(struct cros_ec_keyb * ckdev)404 static int cros_ec_keyb_query_switches(struct cros_ec_keyb *ckdev)
405 {
406 	struct cros_ec_device *ec_dev = ckdev->ec;
407 	union ec_response_get_next_data event_data = {};
408 	int ret;
409 
410 	ret = cros_ec_keyb_info(ec_dev, EC_MKBP_INFO_CURRENT,
411 				EC_MKBP_EVENT_SWITCH, &event_data,
412 				sizeof(event_data.switches));
413 	if (ret)
414 		return ret;
415 
416 	cros_ec_keyb_report_bs(ckdev, EV_SW,
417 			       get_unaligned_le32(&event_data.switches));
418 
419 	return 0;
420 }
421 
422 /**
423  * cros_ec_keyb_resume - Resume the keyboard
424  *
425  * We use the resume notification as a chance to query the EC for switches.
426  *
427  * @dev: The keyboard device
428  *
429  * Returns 0 if no error or -error upon error.
430  */
cros_ec_keyb_resume(struct device * dev)431 static int cros_ec_keyb_resume(struct device *dev)
432 {
433 	struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
434 
435 	if (ckdev->bs_idev)
436 		return cros_ec_keyb_query_switches(ckdev);
437 
438 	return 0;
439 }
440 
441 /**
442  * cros_ec_keyb_register_bs - Register non-matrix buttons/switches
443  *
444  * Handles all the bits of the keyboard driver related to non-matrix buttons
445  * and switches, including asking the EC about which are present and telling
446  * the kernel to expect them.
447  *
448  * If this device has no support for buttons and switches we'll return no error
449  * but the ckdev->bs_idev will remain NULL when this function exits.
450  *
451  * @ckdev: The keyboard device
452  * @expect_buttons_switches: Indicates that EC must report button and/or
453  *   switch events
454  *
455  * Returns 0 if no error or -error upon error.
456  */
cros_ec_keyb_register_bs(struct cros_ec_keyb * ckdev,bool expect_buttons_switches)457 static int cros_ec_keyb_register_bs(struct cros_ec_keyb *ckdev,
458 				    bool expect_buttons_switches)
459 {
460 	struct cros_ec_device *ec_dev = ckdev->ec;
461 	struct device *dev = ckdev->dev;
462 	struct input_dev *idev;
463 	union ec_response_get_next_data event_data = {};
464 	const char *phys;
465 	u32 buttons;
466 	u32 switches;
467 	int ret;
468 	int i;
469 
470 	ret = cros_ec_keyb_info(ec_dev, EC_MKBP_INFO_SUPPORTED,
471 				EC_MKBP_EVENT_BUTTON, &event_data,
472 				sizeof(event_data.buttons));
473 	if (ret)
474 		return ret;
475 	buttons = get_unaligned_le32(&event_data.buttons);
476 
477 	ret = cros_ec_keyb_info(ec_dev, EC_MKBP_INFO_SUPPORTED,
478 				EC_MKBP_EVENT_SWITCH, &event_data,
479 				sizeof(event_data.switches));
480 	if (ret)
481 		return ret;
482 	switches = get_unaligned_le32(&event_data.switches);
483 
484 	if (!buttons && !switches)
485 		return expect_buttons_switches ? -EINVAL : 0;
486 
487 	/*
488 	 * We call the non-matrix buttons/switches 'input1', if present.
489 	 * Allocate phys before input dev, to ensure correct tear-down
490 	 * ordering.
491 	 */
492 	phys = devm_kasprintf(dev, GFP_KERNEL, "%s/input1", ec_dev->phys_name);
493 	if (!phys)
494 		return -ENOMEM;
495 
496 	idev = devm_input_allocate_device(dev);
497 	if (!idev)
498 		return -ENOMEM;
499 
500 	idev->name = "cros_ec_buttons";
501 	idev->phys = phys;
502 	__set_bit(EV_REP, idev->evbit);
503 
504 	idev->id.bustype = BUS_VIRTUAL;
505 	idev->id.version = 1;
506 	idev->id.product = 0;
507 	idev->dev.parent = dev;
508 
509 	input_set_drvdata(idev, ckdev);
510 	ckdev->bs_idev = idev;
511 
512 	for (i = 0; i < ARRAY_SIZE(cros_ec_keyb_bs); i++) {
513 		const struct cros_ec_bs_map *map = &cros_ec_keyb_bs[i];
514 
515 		if ((map->ev_type == EV_KEY && (buttons & BIT(map->bit))) ||
516 		    (map->ev_type == EV_SW && (switches & BIT(map->bit))))
517 			input_set_capability(idev, map->ev_type, map->code);
518 	}
519 
520 	ret = cros_ec_keyb_query_switches(ckdev);
521 	if (ret) {
522 		dev_err(dev, "cannot query switches\n");
523 		return ret;
524 	}
525 
526 	ret = input_register_device(ckdev->bs_idev);
527 	if (ret) {
528 		dev_err(dev, "cannot register input device\n");
529 		return ret;
530 	}
531 
532 	return 0;
533 }
534 
cros_ec_keyb_parse_vivaldi_physmap(struct cros_ec_keyb * ckdev)535 static void cros_ec_keyb_parse_vivaldi_physmap(struct cros_ec_keyb *ckdev)
536 {
537 	u32 *physmap = ckdev->vdata.function_row_physmap;
538 	unsigned int row, col, scancode;
539 	int n_physmap;
540 	int error;
541 	int i;
542 
543 	n_physmap = device_property_count_u32(ckdev->dev,
544 					      "function-row-physmap");
545 	if (n_physmap <= 0)
546 		return;
547 
548 	if (n_physmap >= VIVALDI_MAX_FUNCTION_ROW_KEYS) {
549 		dev_warn(ckdev->dev,
550 			 "only up to %d top row keys is supported (%d specified)\n",
551 			 VIVALDI_MAX_FUNCTION_ROW_KEYS, n_physmap);
552 		n_physmap = VIVALDI_MAX_FUNCTION_ROW_KEYS;
553 	}
554 
555 	error = device_property_read_u32_array(ckdev->dev,
556 					       "function-row-physmap",
557 					       physmap, n_physmap);
558 	if (error) {
559 		dev_warn(ckdev->dev,
560 			 "failed to parse function-row-physmap property: %d\n",
561 			 error);
562 		return;
563 	}
564 
565 	/*
566 	 * Convert (in place) from row/column encoding to matrix "scancode"
567 	 * used by the driver.
568 	 */
569 	for (i = 0; i < n_physmap; i++) {
570 		row = KEY_ROW(physmap[i]);
571 		col = KEY_COL(physmap[i]);
572 		scancode = MATRIX_SCAN_CODE(row, col, ckdev->row_shift);
573 		physmap[i] = scancode;
574 	}
575 
576 	ckdev->vdata.num_function_row_keys = n_physmap;
577 }
578 
579 /**
580  * cros_ec_keyb_register_matrix - Register matrix keys
581  *
582  * Handles all the bits of the keyboard driver related to matrix keys.
583  *
584  * @ckdev: The keyboard device
585  *
586  * Returns 0 if no error or -error upon error.
587  */
cros_ec_keyb_register_matrix(struct cros_ec_keyb * ckdev)588 static int cros_ec_keyb_register_matrix(struct cros_ec_keyb *ckdev)
589 {
590 	struct cros_ec_device *ec_dev = ckdev->ec;
591 	struct device *dev = ckdev->dev;
592 	struct input_dev *idev;
593 	const char *phys;
594 	int err;
595 
596 	err = matrix_keypad_parse_properties(dev, &ckdev->rows, &ckdev->cols);
597 	if (err)
598 		return err;
599 
600 	ckdev->valid_keys = devm_kzalloc(dev, ckdev->cols, GFP_KERNEL);
601 	if (!ckdev->valid_keys)
602 		return -ENOMEM;
603 
604 	ckdev->old_kb_state = devm_kzalloc(dev, ckdev->cols, GFP_KERNEL);
605 	if (!ckdev->old_kb_state)
606 		return -ENOMEM;
607 
608 	/*
609 	 * We call the keyboard matrix 'input0'. Allocate phys before input
610 	 * dev, to ensure correct tear-down ordering.
611 	 */
612 	phys = devm_kasprintf(dev, GFP_KERNEL, "%s/input0", ec_dev->phys_name);
613 	if (!phys)
614 		return -ENOMEM;
615 
616 	idev = devm_input_allocate_device(dev);
617 	if (!idev)
618 		return -ENOMEM;
619 
620 	idev->name = CROS_EC_DEV_NAME;
621 	idev->phys = phys;
622 	__set_bit(EV_REP, idev->evbit);
623 
624 	idev->id.bustype = BUS_VIRTUAL;
625 	idev->id.version = 1;
626 	idev->id.product = 0;
627 	idev->dev.parent = dev;
628 
629 	ckdev->ghost_filter = device_property_read_bool(dev,
630 					"google,needs-ghost-filter");
631 
632 	err = matrix_keypad_build_keymap(NULL, NULL, ckdev->rows, ckdev->cols,
633 					 NULL, idev);
634 	if (err) {
635 		dev_err(dev, "cannot build key matrix\n");
636 		return err;
637 	}
638 
639 	ckdev->row_shift = get_count_order(ckdev->cols);
640 
641 	input_set_capability(idev, EV_MSC, MSC_SCAN);
642 	input_set_drvdata(idev, ckdev);
643 	ckdev->idev = idev;
644 	cros_ec_keyb_compute_valid_keys(ckdev);
645 	cros_ec_keyb_parse_vivaldi_physmap(ckdev);
646 
647 	err = input_register_device(ckdev->idev);
648 	if (err) {
649 		dev_err(dev, "cannot register input device\n");
650 		return err;
651 	}
652 
653 	return 0;
654 }
655 
function_row_physmap_show(struct device * dev,struct device_attribute * attr,char * buf)656 static ssize_t function_row_physmap_show(struct device *dev,
657 					 struct device_attribute *attr,
658 					 char *buf)
659 {
660 	const struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
661 	const struct vivaldi_data *data = &ckdev->vdata;
662 
663 	return vivaldi_function_row_physmap_show(data, buf);
664 }
665 
666 static DEVICE_ATTR_RO(function_row_physmap);
667 
668 static struct attribute *cros_ec_keyb_attrs[] = {
669 	&dev_attr_function_row_physmap.attr,
670 	NULL,
671 };
672 
cros_ec_keyb_attr_is_visible(struct kobject * kobj,struct attribute * attr,int n)673 static umode_t cros_ec_keyb_attr_is_visible(struct kobject *kobj,
674 					    struct attribute *attr,
675 					    int n)
676 {
677 	struct device *dev = kobj_to_dev(kobj);
678 	struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
679 
680 	if (attr == &dev_attr_function_row_physmap.attr &&
681 	    !ckdev->vdata.num_function_row_keys)
682 		return 0;
683 
684 	return attr->mode;
685 }
686 
687 static const struct attribute_group cros_ec_keyb_group = {
688 	.is_visible = cros_ec_keyb_attr_is_visible,
689 	.attrs = cros_ec_keyb_attrs,
690 };
691 __ATTRIBUTE_GROUPS(cros_ec_keyb);
692 
cros_ec_keyb_probe(struct platform_device * pdev)693 static int cros_ec_keyb_probe(struct platform_device *pdev)
694 {
695 	struct cros_ec_device *ec;
696 	struct device *dev = &pdev->dev;
697 	struct cros_ec_keyb *ckdev;
698 	bool buttons_switches_only = device_get_match_data(dev);
699 	int err;
700 
701 	/*
702 	 * If the parent ec device has not been probed yet, defer the probe of
703 	 * this keyboard/button driver until later.
704 	 */
705 	ec = dev_get_drvdata(pdev->dev.parent);
706 	if (!ec)
707 		return -EPROBE_DEFER;
708 
709 	ckdev = devm_kzalloc(dev, sizeof(*ckdev), GFP_KERNEL);
710 	if (!ckdev)
711 		return -ENOMEM;
712 
713 	ckdev->ec = ec;
714 	ckdev->dev = dev;
715 	dev_set_drvdata(dev, ckdev);
716 
717 	if (!buttons_switches_only) {
718 		err = cros_ec_keyb_register_matrix(ckdev);
719 		if (err) {
720 			dev_err(dev, "cannot register matrix inputs: %d\n",
721 				err);
722 			return err;
723 		}
724 	}
725 
726 	err = cros_ec_keyb_register_bs(ckdev, buttons_switches_only);
727 	if (err) {
728 		dev_err(dev, "cannot register non-matrix inputs: %d\n", err);
729 		return err;
730 	}
731 
732 	ckdev->notifier.notifier_call = cros_ec_keyb_work;
733 	err = blocking_notifier_chain_register(&ckdev->ec->event_notifier,
734 					       &ckdev->notifier);
735 	if (err) {
736 		dev_err(dev, "cannot register notifier: %d\n", err);
737 		return err;
738 	}
739 
740 	device_init_wakeup(ckdev->dev, true);
741 	return 0;
742 }
743 
cros_ec_keyb_remove(struct platform_device * pdev)744 static void cros_ec_keyb_remove(struct platform_device *pdev)
745 {
746 	struct cros_ec_keyb *ckdev = dev_get_drvdata(&pdev->dev);
747 
748 	blocking_notifier_chain_unregister(&ckdev->ec->event_notifier,
749 					   &ckdev->notifier);
750 }
751 
752 #ifdef CONFIG_ACPI
753 static const struct acpi_device_id cros_ec_keyb_acpi_match[] = {
754 	{ "GOOG0007", true },
755 	{ }
756 };
757 MODULE_DEVICE_TABLE(acpi, cros_ec_keyb_acpi_match);
758 #endif
759 
760 #ifdef CONFIG_OF
761 static const struct of_device_id cros_ec_keyb_of_match[] = {
762 	{ .compatible = "google,cros-ec-keyb" },
763 	{ .compatible = "google,cros-ec-keyb-switches", .data = (void *)true },
764 	{}
765 };
766 MODULE_DEVICE_TABLE(of, cros_ec_keyb_of_match);
767 #endif
768 
769 static DEFINE_SIMPLE_DEV_PM_OPS(cros_ec_keyb_pm_ops, NULL, cros_ec_keyb_resume);
770 
771 static struct platform_driver cros_ec_keyb_driver = {
772 	.probe = cros_ec_keyb_probe,
773 	.remove_new = cros_ec_keyb_remove,
774 	.driver = {
775 		.name = "cros-ec-keyb",
776 		.dev_groups = cros_ec_keyb_groups,
777 		.of_match_table = of_match_ptr(cros_ec_keyb_of_match),
778 		.acpi_match_table = ACPI_PTR(cros_ec_keyb_acpi_match),
779 		.pm = pm_sleep_ptr(&cros_ec_keyb_pm_ops),
780 	},
781 };
782 
783 module_platform_driver(cros_ec_keyb_driver);
784 
785 MODULE_LICENSE("GPL v2");
786 MODULE_DESCRIPTION("ChromeOS EC keyboard driver");
787 MODULE_ALIAS("platform:cros-ec-keyb");
788