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 <asm/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  * @keymap_data: Matrix keymap data used to convert to keyscan values
39  * @ghost_filter: true to enable the matrix key-ghosting filter
40  * @valid_keys: bitmap of existing keys for each matrix column
41  * @old_kb_state: bitmap of keys pressed last scan
42  * @dev: Device pointer
43  * @ec: Top level ChromeOS device to use to talk to EC
44  * @idev: The input device for the matrix keys.
45  * @bs_idev: The input device for non-matrix buttons and switches (or NULL).
46  * @notifier: interrupt event notifier for transport devices
47  * @vdata: vivaldi function row data
48  */
49 struct cros_ec_keyb {
50 	unsigned int rows;
51 	unsigned int cols;
52 	int row_shift;
53 	const struct matrix_keymap_data *keymap_data;
54 	bool ghost_filter;
55 	uint8_t *valid_keys;
56 	uint8_t *old_kb_state;
57 
58 	struct device *dev;
59 	struct cros_ec_device *ec;
60 
61 	struct input_dev *idev;
62 	struct input_dev *bs_idev;
63 	struct notifier_block notifier;
64 
65 	struct vivaldi_data vdata;
66 };
67 
68 /**
69  * struct cros_ec_bs_map - Mapping between Linux keycodes and EC button/switch
70  *	bitmap #defines
71  *
72  * @ev_type: The type of the input event to generate (e.g., EV_KEY).
73  * @code: A linux keycode
74  * @bit: A #define like EC_MKBP_POWER_BUTTON or EC_MKBP_LID_OPEN
75  * @inverted: If the #define and EV_SW have opposite meanings, this is true.
76  *            Only applicable to switches.
77  */
78 struct cros_ec_bs_map {
79 	unsigned int ev_type;
80 	unsigned int code;
81 	u8 bit;
82 	bool inverted;
83 };
84 
85 /* cros_ec_keyb_bs - Map EC button/switch #defines into kernel ones */
86 static const struct cros_ec_bs_map cros_ec_keyb_bs[] = {
87 	/* Buttons */
88 	{
89 		.ev_type	= EV_KEY,
90 		.code		= KEY_POWER,
91 		.bit		= EC_MKBP_POWER_BUTTON,
92 	},
93 	{
94 		.ev_type	= EV_KEY,
95 		.code		= KEY_VOLUMEUP,
96 		.bit		= EC_MKBP_VOL_UP,
97 	},
98 	{
99 		.ev_type	= EV_KEY,
100 		.code		= KEY_VOLUMEDOWN,
101 		.bit		= EC_MKBP_VOL_DOWN,
102 	},
103 	{
104 		.ev_type        = EV_KEY,
105 		.code           = KEY_BRIGHTNESSUP,
106 		.bit            = EC_MKBP_BRI_UP,
107 	},
108 	{
109 		.ev_type        = EV_KEY,
110 		.code           = KEY_BRIGHTNESSDOWN,
111 		.bit            = EC_MKBP_BRI_DOWN,
112 	},
113 	{
114 		.ev_type        = EV_KEY,
115 		.code           = KEY_SCREENLOCK,
116 		.bit            = EC_MKBP_SCREEN_LOCK,
117 	},
118 
119 	/* Switches */
120 	{
121 		.ev_type	= EV_SW,
122 		.code		= SW_LID,
123 		.bit		= EC_MKBP_LID_OPEN,
124 		.inverted	= true,
125 	},
126 	{
127 		.ev_type	= EV_SW,
128 		.code		= SW_TABLET_MODE,
129 		.bit		= EC_MKBP_TABLET_MODE,
130 	},
131 };
132 
133 /*
134  * Returns true when there is at least one combination of pressed keys that
135  * results in ghosting.
136  */
cros_ec_keyb_has_ghosting(struct cros_ec_keyb * ckdev,uint8_t * buf)137 static bool cros_ec_keyb_has_ghosting(struct cros_ec_keyb *ckdev, uint8_t *buf)
138 {
139 	int col1, col2, buf1, buf2;
140 	struct device *dev = ckdev->dev;
141 	uint8_t *valid_keys = ckdev->valid_keys;
142 
143 	/*
144 	 * Ghosting happens if for any pressed key X there are other keys
145 	 * pressed both in the same row and column of X as, for instance,
146 	 * in the following diagram:
147 	 *
148 	 * . . Y . g .
149 	 * . . . . . .
150 	 * . . . . . .
151 	 * . . X . Z .
152 	 *
153 	 * In this case only X, Y, and Z are pressed, but g appears to be
154 	 * pressed too (see Wikipedia).
155 	 */
156 	for (col1 = 0; col1 < ckdev->cols; col1++) {
157 		buf1 = buf[col1] & valid_keys[col1];
158 		for (col2 = col1 + 1; col2 < ckdev->cols; col2++) {
159 			buf2 = buf[col2] & valid_keys[col2];
160 			if (hweight8(buf1 & buf2) > 1) {
161 				dev_dbg(dev, "ghost found at: B[%02d]:0x%02x & B[%02d]:0x%02x",
162 					col1, buf1, col2, buf2);
163 				return true;
164 			}
165 		}
166 	}
167 
168 	return false;
169 }
170 
171 
172 /*
173  * Compares the new keyboard state to the old one and produces key
174  * press/release events accordingly.  The keyboard state is 13 bytes (one byte
175  * per column)
176  */
cros_ec_keyb_process(struct cros_ec_keyb * ckdev,uint8_t * kb_state,int len)177 static void cros_ec_keyb_process(struct cros_ec_keyb *ckdev,
178 			 uint8_t *kb_state, int len)
179 {
180 	struct input_dev *idev = ckdev->idev;
181 	int col, row;
182 	int new_state;
183 	int old_state;
184 
185 	if (ckdev->ghost_filter && cros_ec_keyb_has_ghosting(ckdev, kb_state)) {
186 		/*
187 		 * Simple-minded solution: ignore this state. The obvious
188 		 * improvement is to only ignore changes to keys involved in
189 		 * the ghosting, but process the other changes.
190 		 */
191 		dev_dbg(ckdev->dev, "ghosting found\n");
192 		return;
193 	}
194 
195 	for (col = 0; col < ckdev->cols; col++) {
196 		for (row = 0; row < ckdev->rows; row++) {
197 			int pos = MATRIX_SCAN_CODE(row, col, ckdev->row_shift);
198 			const unsigned short *keycodes = idev->keycode;
199 
200 			new_state = kb_state[col] & (1 << row);
201 			old_state = ckdev->old_kb_state[col] & (1 << row);
202 			if (new_state != old_state) {
203 				dev_dbg(ckdev->dev,
204 					"changed: [r%d c%d]: byte %02x\n",
205 					row, col, new_state);
206 
207 				input_event(idev, EV_MSC, MSC_SCAN, pos);
208 				input_report_key(idev, keycodes[pos],
209 						 new_state);
210 			}
211 		}
212 		ckdev->old_kb_state[col] = kb_state[col];
213 	}
214 	input_sync(ckdev->idev);
215 }
216 
217 /**
218  * cros_ec_keyb_report_bs - Report non-matrixed buttons or switches
219  *
220  * This takes a bitmap of buttons or switches from the EC and reports events,
221  * syncing at the end.
222  *
223  * @ckdev: The keyboard device.
224  * @ev_type: The input event type (e.g., EV_KEY).
225  * @mask: A bitmap of buttons from the EC.
226  */
cros_ec_keyb_report_bs(struct cros_ec_keyb * ckdev,unsigned int ev_type,u32 mask)227 static void cros_ec_keyb_report_bs(struct cros_ec_keyb *ckdev,
228 				   unsigned int ev_type, u32 mask)
229 
230 {
231 	struct input_dev *idev = ckdev->bs_idev;
232 	int i;
233 
234 	for (i = 0; i < ARRAY_SIZE(cros_ec_keyb_bs); i++) {
235 		const struct cros_ec_bs_map *map = &cros_ec_keyb_bs[i];
236 
237 		if (map->ev_type != ev_type)
238 			continue;
239 
240 		input_event(idev, ev_type, map->code,
241 			    !!(mask & BIT(map->bit)) ^ map->inverted);
242 	}
243 	input_sync(idev);
244 }
245 
cros_ec_keyb_work(struct notifier_block * nb,unsigned long queued_during_suspend,void * _notify)246 static int cros_ec_keyb_work(struct notifier_block *nb,
247 			     unsigned long queued_during_suspend, void *_notify)
248 {
249 	struct cros_ec_keyb *ckdev = container_of(nb, struct cros_ec_keyb,
250 						  notifier);
251 	u32 val;
252 	unsigned int ev_type;
253 
254 	/*
255 	 * If not wake enabled, discard key state changes during
256 	 * suspend. Switches will be re-checked in
257 	 * cros_ec_keyb_resume() to be sure nothing is lost.
258 	 */
259 	if (queued_during_suspend && !device_may_wakeup(ckdev->dev))
260 		return NOTIFY_OK;
261 
262 	switch (ckdev->ec->event_data.event_type) {
263 	case EC_MKBP_EVENT_KEY_MATRIX:
264 		pm_wakeup_event(ckdev->dev, 0);
265 
266 		if (ckdev->ec->event_size != ckdev->cols) {
267 			dev_err(ckdev->dev,
268 				"Discarded incomplete key matrix event.\n");
269 			return NOTIFY_OK;
270 		}
271 
272 		cros_ec_keyb_process(ckdev,
273 				     ckdev->ec->event_data.data.key_matrix,
274 				     ckdev->ec->event_size);
275 		break;
276 
277 	case EC_MKBP_EVENT_SYSRQ:
278 		pm_wakeup_event(ckdev->dev, 0);
279 
280 		val = get_unaligned_le32(&ckdev->ec->event_data.data.sysrq);
281 		dev_dbg(ckdev->dev, "sysrq code from EC: %#x\n", val);
282 		handle_sysrq(val);
283 		break;
284 
285 	case EC_MKBP_EVENT_BUTTON:
286 	case EC_MKBP_EVENT_SWITCH:
287 		pm_wakeup_event(ckdev->dev, 0);
288 
289 		if (ckdev->ec->event_data.event_type == EC_MKBP_EVENT_BUTTON) {
290 			val = get_unaligned_le32(
291 					&ckdev->ec->event_data.data.buttons);
292 			ev_type = EV_KEY;
293 		} else {
294 			val = get_unaligned_le32(
295 					&ckdev->ec->event_data.data.switches);
296 			ev_type = EV_SW;
297 		}
298 		cros_ec_keyb_report_bs(ckdev, ev_type, val);
299 		break;
300 
301 	default:
302 		return NOTIFY_DONE;
303 	}
304 
305 	return NOTIFY_OK;
306 }
307 
308 /*
309  * Walks keycodes flipping bit in buffer COLUMNS deep where bit is ROW.  Used by
310  * ghosting logic to ignore NULL or virtual keys.
311  */
cros_ec_keyb_compute_valid_keys(struct cros_ec_keyb * ckdev)312 static void cros_ec_keyb_compute_valid_keys(struct cros_ec_keyb *ckdev)
313 {
314 	int row, col;
315 	int row_shift = ckdev->row_shift;
316 	unsigned short *keymap = ckdev->idev->keycode;
317 	unsigned short code;
318 
319 	BUG_ON(ckdev->idev->keycodesize != sizeof(*keymap));
320 
321 	for (col = 0; col < ckdev->cols; col++) {
322 		for (row = 0; row < ckdev->rows; row++) {
323 			code = keymap[MATRIX_SCAN_CODE(row, col, row_shift)];
324 			if (code && (code != KEY_BATTERY))
325 				ckdev->valid_keys[col] |= 1 << row;
326 		}
327 		dev_dbg(ckdev->dev, "valid_keys[%02d] = 0x%02x\n",
328 			col, ckdev->valid_keys[col]);
329 	}
330 }
331 
332 /**
333  * cros_ec_keyb_info - Wrap the EC command EC_CMD_MKBP_INFO
334  *
335  * This wraps the EC_CMD_MKBP_INFO, abstracting out all of the marshalling and
336  * unmarshalling and different version nonsense into something simple.
337  *
338  * @ec_dev: The EC device
339  * @info_type: Either EC_MKBP_INFO_SUPPORTED or EC_MKBP_INFO_CURRENT.
340  * @event_type: Either EC_MKBP_EVENT_BUTTON or EC_MKBP_EVENT_SWITCH.  Actually
341  *              in some cases this could be EC_MKBP_EVENT_KEY_MATRIX or
342  *              EC_MKBP_EVENT_HOST_EVENT too but we don't use in this driver.
343  * @result: Where we'll store the result; a union
344  * @result_size: The size of the result.  Expected to be the size of one of
345  *               the elements in the union.
346  *
347  * Returns 0 if no error or -error upon error.
348  */
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)349 static int cros_ec_keyb_info(struct cros_ec_device *ec_dev,
350 			     enum ec_mkbp_info_type info_type,
351 			     enum ec_mkbp_event event_type,
352 			     union ec_response_get_next_data *result,
353 			     size_t result_size)
354 {
355 	struct ec_params_mkbp_info *params;
356 	struct cros_ec_command *msg;
357 	int ret;
358 
359 	msg = kzalloc(sizeof(*msg) + max_t(size_t, result_size,
360 					   sizeof(*params)), GFP_KERNEL);
361 	if (!msg)
362 		return -ENOMEM;
363 
364 	msg->command = EC_CMD_MKBP_INFO;
365 	msg->version = 1;
366 	msg->outsize = sizeof(*params);
367 	msg->insize = result_size;
368 	params = (struct ec_params_mkbp_info *)msg->data;
369 	params->info_type = info_type;
370 	params->event_type = event_type;
371 
372 	ret = cros_ec_cmd_xfer_status(ec_dev, msg);
373 	if (ret == -ENOPROTOOPT) {
374 		/* With older ECs we just return 0 for everything */
375 		memset(result, 0, result_size);
376 		ret = 0;
377 	} else if (ret < 0) {
378 		dev_warn(ec_dev->dev, "Transfer error %d/%d: %d\n",
379 			 (int)info_type, (int)event_type, ret);
380 	} else if (ret != result_size) {
381 		dev_warn(ec_dev->dev, "Wrong size %d/%d: %d != %zu\n",
382 			 (int)info_type, (int)event_type,
383 			 ret, result_size);
384 		ret = -EPROTO;
385 	} else {
386 		memcpy(result, msg->data, result_size);
387 		ret = 0;
388 	}
389 
390 	kfree(msg);
391 
392 	return ret;
393 }
394 
395 /**
396  * cros_ec_keyb_query_switches - Query the state of switches and report
397  *
398  * This will ask the EC about the current state of switches and report to the
399  * kernel.  Note that we don't query for buttons because they are more
400  * transitory and we'll get an update on the next release / press.
401  *
402  * @ckdev: The keyboard device
403  *
404  * Returns 0 if no error or -error upon error.
405  */
cros_ec_keyb_query_switches(struct cros_ec_keyb * ckdev)406 static int cros_ec_keyb_query_switches(struct cros_ec_keyb *ckdev)
407 {
408 	struct cros_ec_device *ec_dev = ckdev->ec;
409 	union ec_response_get_next_data event_data = {};
410 	int ret;
411 
412 	ret = cros_ec_keyb_info(ec_dev, EC_MKBP_INFO_CURRENT,
413 				EC_MKBP_EVENT_SWITCH, &event_data,
414 				sizeof(event_data.switches));
415 	if (ret)
416 		return ret;
417 
418 	cros_ec_keyb_report_bs(ckdev, EV_SW,
419 			       get_unaligned_le32(&event_data.switches));
420 
421 	return 0;
422 }
423 
424 /**
425  * cros_ec_keyb_resume - Resume the keyboard
426  *
427  * We use the resume notification as a chance to query the EC for switches.
428  *
429  * @dev: The keyboard device
430  *
431  * Returns 0 if no error or -error upon error.
432  */
cros_ec_keyb_resume(struct device * dev)433 static int cros_ec_keyb_resume(struct device *dev)
434 {
435 	struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
436 
437 	if (ckdev->bs_idev)
438 		return cros_ec_keyb_query_switches(ckdev);
439 
440 	return 0;
441 }
442 
443 /**
444  * cros_ec_keyb_register_bs - Register non-matrix buttons/switches
445  *
446  * Handles all the bits of the keyboard driver related to non-matrix buttons
447  * and switches, including asking the EC about which are present and telling
448  * the kernel to expect them.
449  *
450  * If this device has no support for buttons and switches we'll return no error
451  * but the ckdev->bs_idev will remain NULL when this function exits.
452  *
453  * @ckdev: The keyboard device
454  * @expect_buttons_switches: Indicates that EC must report button and/or
455  *   switch events
456  *
457  * Returns 0 if no error or -error upon error.
458  */
cros_ec_keyb_register_bs(struct cros_ec_keyb * ckdev,bool expect_buttons_switches)459 static int cros_ec_keyb_register_bs(struct cros_ec_keyb *ckdev,
460 				    bool expect_buttons_switches)
461 {
462 	struct cros_ec_device *ec_dev = ckdev->ec;
463 	struct device *dev = ckdev->dev;
464 	struct input_dev *idev;
465 	union ec_response_get_next_data event_data = {};
466 	const char *phys;
467 	u32 buttons;
468 	u32 switches;
469 	int ret;
470 	int i;
471 
472 	ret = cros_ec_keyb_info(ec_dev, EC_MKBP_INFO_SUPPORTED,
473 				EC_MKBP_EVENT_BUTTON, &event_data,
474 				sizeof(event_data.buttons));
475 	if (ret)
476 		return ret;
477 	buttons = get_unaligned_le32(&event_data.buttons);
478 
479 	ret = cros_ec_keyb_info(ec_dev, EC_MKBP_INFO_SUPPORTED,
480 				EC_MKBP_EVENT_SWITCH, &event_data,
481 				sizeof(event_data.switches));
482 	if (ret)
483 		return ret;
484 	switches = get_unaligned_le32(&event_data.switches);
485 
486 	if (!buttons && !switches)
487 		return expect_buttons_switches ? -EINVAL : 0;
488 
489 	/*
490 	 * We call the non-matrix buttons/switches 'input1', if present.
491 	 * Allocate phys before input dev, to ensure correct tear-down
492 	 * ordering.
493 	 */
494 	phys = devm_kasprintf(dev, GFP_KERNEL, "%s/input1", ec_dev->phys_name);
495 	if (!phys)
496 		return -ENOMEM;
497 
498 	idev = devm_input_allocate_device(dev);
499 	if (!idev)
500 		return -ENOMEM;
501 
502 	idev->name = "cros_ec_buttons";
503 	idev->phys = phys;
504 	__set_bit(EV_REP, idev->evbit);
505 
506 	idev->id.bustype = BUS_VIRTUAL;
507 	idev->id.version = 1;
508 	idev->id.product = 0;
509 	idev->dev.parent = dev;
510 
511 	input_set_drvdata(idev, ckdev);
512 	ckdev->bs_idev = idev;
513 
514 	for (i = 0; i < ARRAY_SIZE(cros_ec_keyb_bs); i++) {
515 		const struct cros_ec_bs_map *map = &cros_ec_keyb_bs[i];
516 
517 		if ((map->ev_type == EV_KEY && (buttons & BIT(map->bit))) ||
518 		    (map->ev_type == EV_SW && (switches & BIT(map->bit))))
519 			input_set_capability(idev, map->ev_type, map->code);
520 	}
521 
522 	ret = cros_ec_keyb_query_switches(ckdev);
523 	if (ret) {
524 		dev_err(dev, "cannot query switches\n");
525 		return ret;
526 	}
527 
528 	ret = input_register_device(ckdev->bs_idev);
529 	if (ret) {
530 		dev_err(dev, "cannot register input device\n");
531 		return ret;
532 	}
533 
534 	return 0;
535 }
536 
cros_ec_keyb_parse_vivaldi_physmap(struct cros_ec_keyb * ckdev)537 static void cros_ec_keyb_parse_vivaldi_physmap(struct cros_ec_keyb *ckdev)
538 {
539 	u32 *physmap = ckdev->vdata.function_row_physmap;
540 	unsigned int row, col, scancode;
541 	int n_physmap;
542 	int error;
543 	int i;
544 
545 	n_physmap = device_property_count_u32(ckdev->dev,
546 					      "function-row-physmap");
547 	if (n_physmap <= 0)
548 		return;
549 
550 	if (n_physmap >= VIVALDI_MAX_FUNCTION_ROW_KEYS) {
551 		dev_warn(ckdev->dev,
552 			 "only up to %d top row keys is supported (%d specified)\n",
553 			 VIVALDI_MAX_FUNCTION_ROW_KEYS, n_physmap);
554 		n_physmap = VIVALDI_MAX_FUNCTION_ROW_KEYS;
555 	}
556 
557 	error = device_property_read_u32_array(ckdev->dev,
558 					       "function-row-physmap",
559 					       physmap, n_physmap);
560 	if (error) {
561 		dev_warn(ckdev->dev,
562 			 "failed to parse function-row-physmap property: %d\n",
563 			 error);
564 		return;
565 	}
566 
567 	/*
568 	 * Convert (in place) from row/column encoding to matrix "scancode"
569 	 * used by the driver.
570 	 */
571 	for (i = 0; i < n_physmap; i++) {
572 		row = KEY_ROW(physmap[i]);
573 		col = KEY_COL(physmap[i]);
574 		scancode = MATRIX_SCAN_CODE(row, col, ckdev->row_shift);
575 		physmap[i] = scancode;
576 	}
577 
578 	ckdev->vdata.num_function_row_keys = n_physmap;
579 }
580 
581 /**
582  * cros_ec_keyb_register_matrix - Register matrix keys
583  *
584  * Handles all the bits of the keyboard driver related to matrix keys.
585  *
586  * @ckdev: The keyboard device
587  *
588  * Returns 0 if no error or -error upon error.
589  */
cros_ec_keyb_register_matrix(struct cros_ec_keyb * ckdev)590 static int cros_ec_keyb_register_matrix(struct cros_ec_keyb *ckdev)
591 {
592 	struct cros_ec_device *ec_dev = ckdev->ec;
593 	struct device *dev = ckdev->dev;
594 	struct input_dev *idev;
595 	const char *phys;
596 	int err;
597 
598 	err = matrix_keypad_parse_properties(dev, &ckdev->rows, &ckdev->cols);
599 	if (err)
600 		return err;
601 
602 	ckdev->valid_keys = devm_kzalloc(dev, ckdev->cols, GFP_KERNEL);
603 	if (!ckdev->valid_keys)
604 		return -ENOMEM;
605 
606 	ckdev->old_kb_state = devm_kzalloc(dev, ckdev->cols, GFP_KERNEL);
607 	if (!ckdev->old_kb_state)
608 		return -ENOMEM;
609 
610 	/*
611 	 * We call the keyboard matrix 'input0'. Allocate phys before input
612 	 * dev, to ensure correct tear-down ordering.
613 	 */
614 	phys = devm_kasprintf(dev, GFP_KERNEL, "%s/input0", ec_dev->phys_name);
615 	if (!phys)
616 		return -ENOMEM;
617 
618 	idev = devm_input_allocate_device(dev);
619 	if (!idev)
620 		return -ENOMEM;
621 
622 	idev->name = CROS_EC_DEV_NAME;
623 	idev->phys = phys;
624 	__set_bit(EV_REP, idev->evbit);
625 
626 	idev->id.bustype = BUS_VIRTUAL;
627 	idev->id.version = 1;
628 	idev->id.product = 0;
629 	idev->dev.parent = dev;
630 
631 	ckdev->ghost_filter = device_property_read_bool(dev,
632 					"google,needs-ghost-filter");
633 
634 	err = matrix_keypad_build_keymap(NULL, NULL, ckdev->rows, ckdev->cols,
635 					 NULL, idev);
636 	if (err) {
637 		dev_err(dev, "cannot build key matrix\n");
638 		return err;
639 	}
640 
641 	ckdev->row_shift = get_count_order(ckdev->cols);
642 
643 	input_set_capability(idev, EV_MSC, MSC_SCAN);
644 	input_set_drvdata(idev, ckdev);
645 	ckdev->idev = idev;
646 	cros_ec_keyb_compute_valid_keys(ckdev);
647 	cros_ec_keyb_parse_vivaldi_physmap(ckdev);
648 
649 	err = input_register_device(ckdev->idev);
650 	if (err) {
651 		dev_err(dev, "cannot register input device\n");
652 		return err;
653 	}
654 
655 	return 0;
656 }
657 
function_row_physmap_show(struct device * dev,struct device_attribute * attr,char * buf)658 static ssize_t function_row_physmap_show(struct device *dev,
659 					 struct device_attribute *attr,
660 					 char *buf)
661 {
662 	const struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
663 	const struct vivaldi_data *data = &ckdev->vdata;
664 
665 	return vivaldi_function_row_physmap_show(data, buf);
666 }
667 
668 static DEVICE_ATTR_RO(function_row_physmap);
669 
670 static struct attribute *cros_ec_keyb_attrs[] = {
671 	&dev_attr_function_row_physmap.attr,
672 	NULL,
673 };
674 
cros_ec_keyb_attr_is_visible(struct kobject * kobj,struct attribute * attr,int n)675 static umode_t cros_ec_keyb_attr_is_visible(struct kobject *kobj,
676 					    struct attribute *attr,
677 					    int n)
678 {
679 	struct device *dev = kobj_to_dev(kobj);
680 	struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
681 
682 	if (attr == &dev_attr_function_row_physmap.attr &&
683 	    !ckdev->vdata.num_function_row_keys)
684 		return 0;
685 
686 	return attr->mode;
687 }
688 
689 static const struct attribute_group cros_ec_keyb_attr_group = {
690 	.is_visible = cros_ec_keyb_attr_is_visible,
691 	.attrs = cros_ec_keyb_attrs,
692 };
693 
cros_ec_keyb_probe(struct platform_device * pdev)694 static int cros_ec_keyb_probe(struct platform_device *pdev)
695 {
696 	struct cros_ec_device *ec;
697 	struct device *dev = &pdev->dev;
698 	struct cros_ec_keyb *ckdev;
699 	bool buttons_switches_only = device_get_match_data(dev);
700 	int err;
701 
702 	/*
703 	 * If the parent ec device has not been probed yet, defer the probe of
704 	 * this keyboard/button driver until later.
705 	 */
706 	ec = dev_get_drvdata(pdev->dev.parent);
707 	if (!ec)
708 		return -EPROBE_DEFER;
709 
710 	ckdev = devm_kzalloc(dev, sizeof(*ckdev), GFP_KERNEL);
711 	if (!ckdev)
712 		return -ENOMEM;
713 
714 	ckdev->ec = ec;
715 	ckdev->dev = dev;
716 	dev_set_drvdata(dev, ckdev);
717 
718 	if (!buttons_switches_only) {
719 		err = cros_ec_keyb_register_matrix(ckdev);
720 		if (err) {
721 			dev_err(dev, "cannot register matrix inputs: %d\n",
722 				err);
723 			return err;
724 		}
725 	}
726 
727 	err = cros_ec_keyb_register_bs(ckdev, buttons_switches_only);
728 	if (err) {
729 		dev_err(dev, "cannot register non-matrix inputs: %d\n", err);
730 		return err;
731 	}
732 
733 	err = devm_device_add_group(dev, &cros_ec_keyb_attr_group);
734 	if (err) {
735 		dev_err(dev, "failed to create attributes: %d\n", err);
736 		return err;
737 	}
738 
739 	ckdev->notifier.notifier_call = cros_ec_keyb_work;
740 	err = blocking_notifier_chain_register(&ckdev->ec->event_notifier,
741 					       &ckdev->notifier);
742 	if (err) {
743 		dev_err(dev, "cannot register notifier: %d\n", err);
744 		return err;
745 	}
746 
747 	device_init_wakeup(ckdev->dev, true);
748 	return 0;
749 }
750 
cros_ec_keyb_remove(struct platform_device * pdev)751 static int cros_ec_keyb_remove(struct platform_device *pdev)
752 {
753 	struct cros_ec_keyb *ckdev = dev_get_drvdata(&pdev->dev);
754 
755 	blocking_notifier_chain_unregister(&ckdev->ec->event_notifier,
756 					   &ckdev->notifier);
757 
758 	return 0;
759 }
760 
761 #ifdef CONFIG_ACPI
762 static const struct acpi_device_id cros_ec_keyb_acpi_match[] = {
763 	{ "GOOG0007", true },
764 	{ }
765 };
766 MODULE_DEVICE_TABLE(acpi, cros_ec_keyb_acpi_match);
767 #endif
768 
769 #ifdef CONFIG_OF
770 static const struct of_device_id cros_ec_keyb_of_match[] = {
771 	{ .compatible = "google,cros-ec-keyb" },
772 	{ .compatible = "google,cros-ec-keyb-switches", .data = (void *)true },
773 	{}
774 };
775 MODULE_DEVICE_TABLE(of, cros_ec_keyb_of_match);
776 #endif
777 
778 static DEFINE_SIMPLE_DEV_PM_OPS(cros_ec_keyb_pm_ops, NULL, cros_ec_keyb_resume);
779 
780 static struct platform_driver cros_ec_keyb_driver = {
781 	.probe = cros_ec_keyb_probe,
782 	.remove = cros_ec_keyb_remove,
783 	.driver = {
784 		.name = "cros-ec-keyb",
785 		.of_match_table = of_match_ptr(cros_ec_keyb_of_match),
786 		.acpi_match_table = ACPI_PTR(cros_ec_keyb_acpi_match),
787 		.pm = pm_sleep_ptr(&cros_ec_keyb_pm_ops),
788 	},
789 };
790 
791 module_platform_driver(cros_ec_keyb_driver);
792 
793 MODULE_LICENSE("GPL v2");
794 MODULE_DESCRIPTION("ChromeOS EC keyboard driver");
795 MODULE_ALIAS("platform:cros-ec-keyb");
796