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v6.2
  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 */
 49struct 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 */
 78struct 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 */
 86static 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	/* Switches */
105	{
106		.ev_type	= EV_SW,
107		.code		= SW_LID,
108		.bit		= EC_MKBP_LID_OPEN,
109		.inverted	= true,
110	},
111	{
112		.ev_type	= EV_SW,
113		.code		= SW_TABLET_MODE,
114		.bit		= EC_MKBP_TABLET_MODE,
115	},
116};
117
118/*
119 * Returns true when there is at least one combination of pressed keys that
120 * results in ghosting.
121 */
122static bool cros_ec_keyb_has_ghosting(struct cros_ec_keyb *ckdev, uint8_t *buf)
123{
124	int col1, col2, buf1, buf2;
125	struct device *dev = ckdev->dev;
126	uint8_t *valid_keys = ckdev->valid_keys;
127
128	/*
129	 * Ghosting happens if for any pressed key X there are other keys
130	 * pressed both in the same row and column of X as, for instance,
131	 * in the following diagram:
132	 *
133	 * . . Y . g .
134	 * . . . . . .
135	 * . . . . . .
136	 * . . X . Z .
137	 *
138	 * In this case only X, Y, and Z are pressed, but g appears to be
139	 * pressed too (see Wikipedia).
140	 */
141	for (col1 = 0; col1 < ckdev->cols; col1++) {
142		buf1 = buf[col1] & valid_keys[col1];
143		for (col2 = col1 + 1; col2 < ckdev->cols; col2++) {
144			buf2 = buf[col2] & valid_keys[col2];
145			if (hweight8(buf1 & buf2) > 1) {
146				dev_dbg(dev, "ghost found at: B[%02d]:0x%02x & B[%02d]:0x%02x",
147					col1, buf1, col2, buf2);
148				return true;
149			}
150		}
151	}
152
153	return false;
154}
155
156
157/*
158 * Compares the new keyboard state to the old one and produces key
159 * press/release events accordingly.  The keyboard state is 13 bytes (one byte
160 * per column)
161 */
162static void cros_ec_keyb_process(struct cros_ec_keyb *ckdev,
163			 uint8_t *kb_state, int len)
164{
165	struct input_dev *idev = ckdev->idev;
166	int col, row;
167	int new_state;
168	int old_state;
169
170	if (ckdev->ghost_filter && cros_ec_keyb_has_ghosting(ckdev, kb_state)) {
171		/*
172		 * Simple-minded solution: ignore this state. The obvious
173		 * improvement is to only ignore changes to keys involved in
174		 * the ghosting, but process the other changes.
175		 */
176		dev_dbg(ckdev->dev, "ghosting found\n");
177		return;
178	}
179
180	for (col = 0; col < ckdev->cols; col++) {
181		for (row = 0; row < ckdev->rows; row++) {
182			int pos = MATRIX_SCAN_CODE(row, col, ckdev->row_shift);
183			const unsigned short *keycodes = idev->keycode;
184
185			new_state = kb_state[col] & (1 << row);
186			old_state = ckdev->old_kb_state[col] & (1 << row);
187			if (new_state != old_state) {
188				dev_dbg(ckdev->dev,
189					"changed: [r%d c%d]: byte %02x\n",
190					row, col, new_state);
191
192				input_event(idev, EV_MSC, MSC_SCAN, pos);
193				input_report_key(idev, keycodes[pos],
194						 new_state);
195			}
196		}
197		ckdev->old_kb_state[col] = kb_state[col];
198	}
199	input_sync(ckdev->idev);
200}
201
202/**
203 * cros_ec_keyb_report_bs - Report non-matrixed buttons or switches
204 *
205 * This takes a bitmap of buttons or switches from the EC and reports events,
206 * syncing at the end.
207 *
208 * @ckdev: The keyboard device.
209 * @ev_type: The input event type (e.g., EV_KEY).
210 * @mask: A bitmap of buttons from the EC.
211 */
212static void cros_ec_keyb_report_bs(struct cros_ec_keyb *ckdev,
213				   unsigned int ev_type, u32 mask)
214
215{
216	struct input_dev *idev = ckdev->bs_idev;
217	int i;
218
219	for (i = 0; i < ARRAY_SIZE(cros_ec_keyb_bs); i++) {
220		const struct cros_ec_bs_map *map = &cros_ec_keyb_bs[i];
221
222		if (map->ev_type != ev_type)
223			continue;
224
225		input_event(idev, ev_type, map->code,
226			    !!(mask & BIT(map->bit)) ^ map->inverted);
227	}
228	input_sync(idev);
229}
230
231static int cros_ec_keyb_work(struct notifier_block *nb,
232			     unsigned long queued_during_suspend, void *_notify)
233{
234	struct cros_ec_keyb *ckdev = container_of(nb, struct cros_ec_keyb,
235						  notifier);
236	u32 val;
237	unsigned int ev_type;
238
239	/*
240	 * If not wake enabled, discard key state changes during
241	 * suspend. Switches will be re-checked in
242	 * cros_ec_keyb_resume() to be sure nothing is lost.
243	 */
244	if (queued_during_suspend && !device_may_wakeup(ckdev->dev))
245		return NOTIFY_OK;
246
247	switch (ckdev->ec->event_data.event_type) {
248	case EC_MKBP_EVENT_KEY_MATRIX:
249		pm_wakeup_event(ckdev->dev, 0);
250
251		if (ckdev->ec->event_size != ckdev->cols) {
252			dev_err(ckdev->dev,
253				"Discarded incomplete key matrix event.\n");
254			return NOTIFY_OK;
255		}
256
257		cros_ec_keyb_process(ckdev,
258				     ckdev->ec->event_data.data.key_matrix,
259				     ckdev->ec->event_size);
260		break;
261
262	case EC_MKBP_EVENT_SYSRQ:
263		pm_wakeup_event(ckdev->dev, 0);
264
265		val = get_unaligned_le32(&ckdev->ec->event_data.data.sysrq);
266		dev_dbg(ckdev->dev, "sysrq code from EC: %#x\n", val);
267		handle_sysrq(val);
268		break;
269
270	case EC_MKBP_EVENT_BUTTON:
271	case EC_MKBP_EVENT_SWITCH:
272		pm_wakeup_event(ckdev->dev, 0);
273
274		if (ckdev->ec->event_data.event_type == EC_MKBP_EVENT_BUTTON) {
275			val = get_unaligned_le32(
276					&ckdev->ec->event_data.data.buttons);
277			ev_type = EV_KEY;
278		} else {
279			val = get_unaligned_le32(
280					&ckdev->ec->event_data.data.switches);
281			ev_type = EV_SW;
282		}
283		cros_ec_keyb_report_bs(ckdev, ev_type, val);
284		break;
285
286	default:
287		return NOTIFY_DONE;
288	}
289
290	return NOTIFY_OK;
291}
292
293/*
294 * Walks keycodes flipping bit in buffer COLUMNS deep where bit is ROW.  Used by
295 * ghosting logic to ignore NULL or virtual keys.
296 */
297static void cros_ec_keyb_compute_valid_keys(struct cros_ec_keyb *ckdev)
298{
299	int row, col;
300	int row_shift = ckdev->row_shift;
301	unsigned short *keymap = ckdev->idev->keycode;
302	unsigned short code;
303
304	BUG_ON(ckdev->idev->keycodesize != sizeof(*keymap));
305
306	for (col = 0; col < ckdev->cols; col++) {
307		for (row = 0; row < ckdev->rows; row++) {
308			code = keymap[MATRIX_SCAN_CODE(row, col, row_shift)];
309			if (code && (code != KEY_BATTERY))
310				ckdev->valid_keys[col] |= 1 << row;
311		}
312		dev_dbg(ckdev->dev, "valid_keys[%02d] = 0x%02x\n",
313			col, ckdev->valid_keys[col]);
314	}
315}
316
317/**
318 * cros_ec_keyb_info - Wrap the EC command EC_CMD_MKBP_INFO
319 *
320 * This wraps the EC_CMD_MKBP_INFO, abstracting out all of the marshalling and
321 * unmarshalling and different version nonsense into something simple.
322 *
323 * @ec_dev: The EC device
324 * @info_type: Either EC_MKBP_INFO_SUPPORTED or EC_MKBP_INFO_CURRENT.
325 * @event_type: Either EC_MKBP_EVENT_BUTTON or EC_MKBP_EVENT_SWITCH.  Actually
326 *              in some cases this could be EC_MKBP_EVENT_KEY_MATRIX or
327 *              EC_MKBP_EVENT_HOST_EVENT too but we don't use in this driver.
328 * @result: Where we'll store the result; a union
329 * @result_size: The size of the result.  Expected to be the size of one of
330 *               the elements in the union.
331 *
332 * Returns 0 if no error or -error upon error.
333 */
334static int cros_ec_keyb_info(struct cros_ec_device *ec_dev,
335			     enum ec_mkbp_info_type info_type,
336			     enum ec_mkbp_event event_type,
337			     union ec_response_get_next_data *result,
338			     size_t result_size)
339{
340	struct ec_params_mkbp_info *params;
341	struct cros_ec_command *msg;
342	int ret;
343
344	msg = kzalloc(sizeof(*msg) + max_t(size_t, result_size,
345					   sizeof(*params)), GFP_KERNEL);
346	if (!msg)
347		return -ENOMEM;
348
349	msg->command = EC_CMD_MKBP_INFO;
350	msg->version = 1;
351	msg->outsize = sizeof(*params);
352	msg->insize = result_size;
353	params = (struct ec_params_mkbp_info *)msg->data;
354	params->info_type = info_type;
355	params->event_type = event_type;
356
357	ret = cros_ec_cmd_xfer_status(ec_dev, msg);
358	if (ret == -ENOPROTOOPT) {
359		/* With older ECs we just return 0 for everything */
360		memset(result, 0, result_size);
361		ret = 0;
362	} else if (ret < 0) {
363		dev_warn(ec_dev->dev, "Transfer error %d/%d: %d\n",
364			 (int)info_type, (int)event_type, ret);
365	} else if (ret != result_size) {
366		dev_warn(ec_dev->dev, "Wrong size %d/%d: %d != %zu\n",
367			 (int)info_type, (int)event_type,
368			 ret, result_size);
369		ret = -EPROTO;
370	} else {
371		memcpy(result, msg->data, result_size);
372		ret = 0;
373	}
374
375	kfree(msg);
376
377	return ret;
378}
379
380/**
381 * cros_ec_keyb_query_switches - Query the state of switches and report
382 *
383 * This will ask the EC about the current state of switches and report to the
384 * kernel.  Note that we don't query for buttons because they are more
385 * transitory and we'll get an update on the next release / press.
386 *
387 * @ckdev: The keyboard device
388 *
389 * Returns 0 if no error or -error upon error.
390 */
391static int cros_ec_keyb_query_switches(struct cros_ec_keyb *ckdev)
392{
393	struct cros_ec_device *ec_dev = ckdev->ec;
394	union ec_response_get_next_data event_data = {};
395	int ret;
396
397	ret = cros_ec_keyb_info(ec_dev, EC_MKBP_INFO_CURRENT,
398				EC_MKBP_EVENT_SWITCH, &event_data,
399				sizeof(event_data.switches));
400	if (ret)
401		return ret;
402
403	cros_ec_keyb_report_bs(ckdev, EV_SW,
404			       get_unaligned_le32(&event_data.switches));
405
406	return 0;
407}
408
409/**
410 * cros_ec_keyb_resume - Resume the keyboard
411 *
412 * We use the resume notification as a chance to query the EC for switches.
413 *
414 * @dev: The keyboard device
415 *
416 * Returns 0 if no error or -error upon error.
417 */
418static int cros_ec_keyb_resume(struct device *dev)
419{
420	struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
421
422	if (ckdev->bs_idev)
423		return cros_ec_keyb_query_switches(ckdev);
424
425	return 0;
426}
427
428/**
429 * cros_ec_keyb_register_bs - Register non-matrix buttons/switches
430 *
431 * Handles all the bits of the keyboard driver related to non-matrix buttons
432 * and switches, including asking the EC about which are present and telling
433 * the kernel to expect them.
434 *
435 * If this device has no support for buttons and switches we'll return no error
436 * but the ckdev->bs_idev will remain NULL when this function exits.
437 *
438 * @ckdev: The keyboard device
439 * @expect_buttons_switches: Indicates that EC must report button and/or
440 *   switch events
441 *
442 * Returns 0 if no error or -error upon error.
443 */
444static int cros_ec_keyb_register_bs(struct cros_ec_keyb *ckdev,
445				    bool expect_buttons_switches)
446{
447	struct cros_ec_device *ec_dev = ckdev->ec;
448	struct device *dev = ckdev->dev;
449	struct input_dev *idev;
450	union ec_response_get_next_data event_data = {};
451	const char *phys;
452	u32 buttons;
453	u32 switches;
454	int ret;
455	int i;
456
457	ret = cros_ec_keyb_info(ec_dev, EC_MKBP_INFO_SUPPORTED,
458				EC_MKBP_EVENT_BUTTON, &event_data,
459				sizeof(event_data.buttons));
460	if (ret)
461		return ret;
462	buttons = get_unaligned_le32(&event_data.buttons);
463
464	ret = cros_ec_keyb_info(ec_dev, EC_MKBP_INFO_SUPPORTED,
465				EC_MKBP_EVENT_SWITCH, &event_data,
466				sizeof(event_data.switches));
467	if (ret)
468		return ret;
469	switches = get_unaligned_le32(&event_data.switches);
470
471	if (!buttons && !switches)
472		return expect_buttons_switches ? -EINVAL : 0;
473
474	/*
475	 * We call the non-matrix buttons/switches 'input1', if present.
476	 * Allocate phys before input dev, to ensure correct tear-down
477	 * ordering.
478	 */
479	phys = devm_kasprintf(dev, GFP_KERNEL, "%s/input1", ec_dev->phys_name);
480	if (!phys)
481		return -ENOMEM;
482
483	idev = devm_input_allocate_device(dev);
484	if (!idev)
485		return -ENOMEM;
486
487	idev->name = "cros_ec_buttons";
488	idev->phys = phys;
489	__set_bit(EV_REP, idev->evbit);
490
491	idev->id.bustype = BUS_VIRTUAL;
492	idev->id.version = 1;
493	idev->id.product = 0;
494	idev->dev.parent = dev;
495
496	input_set_drvdata(idev, ckdev);
497	ckdev->bs_idev = idev;
498
499	for (i = 0; i < ARRAY_SIZE(cros_ec_keyb_bs); i++) {
500		const struct cros_ec_bs_map *map = &cros_ec_keyb_bs[i];
501
502		if ((map->ev_type == EV_KEY && (buttons & BIT(map->bit))) ||
503		    (map->ev_type == EV_SW && (switches & BIT(map->bit))))
504			input_set_capability(idev, map->ev_type, map->code);
505	}
506
507	ret = cros_ec_keyb_query_switches(ckdev);
508	if (ret) {
509		dev_err(dev, "cannot query switches\n");
510		return ret;
511	}
512
513	ret = input_register_device(ckdev->bs_idev);
514	if (ret) {
515		dev_err(dev, "cannot register input device\n");
516		return ret;
517	}
518
519	return 0;
520}
521
522static void cros_ec_keyb_parse_vivaldi_physmap(struct cros_ec_keyb *ckdev)
523{
524	u32 *physmap = ckdev->vdata.function_row_physmap;
525	unsigned int row, col, scancode;
526	int n_physmap;
527	int error;
528	int i;
529
530	n_physmap = device_property_count_u32(ckdev->dev,
531					      "function-row-physmap");
532	if (n_physmap <= 0)
533		return;
534
535	if (n_physmap >= VIVALDI_MAX_FUNCTION_ROW_KEYS) {
536		dev_warn(ckdev->dev,
537			 "only up to %d top row keys is supported (%d specified)\n",
538			 VIVALDI_MAX_FUNCTION_ROW_KEYS, n_physmap);
539		n_physmap = VIVALDI_MAX_FUNCTION_ROW_KEYS;
540	}
541
542	error = device_property_read_u32_array(ckdev->dev,
543					       "function-row-physmap",
544					       physmap, n_physmap);
545	if (error) {
546		dev_warn(ckdev->dev,
547			 "failed to parse function-row-physmap property: %d\n",
548			 error);
549		return;
550	}
551
552	/*
553	 * Convert (in place) from row/column encoding to matrix "scancode"
554	 * used by the driver.
555	 */
556	for (i = 0; i < n_physmap; i++) {
557		row = KEY_ROW(physmap[i]);
558		col = KEY_COL(physmap[i]);
559		scancode = MATRIX_SCAN_CODE(row, col, ckdev->row_shift);
560		physmap[i] = scancode;
561	}
562
563	ckdev->vdata.num_function_row_keys = n_physmap;
564}
565
566/**
567 * cros_ec_keyb_register_matrix - Register matrix keys
568 *
569 * Handles all the bits of the keyboard driver related to matrix keys.
570 *
571 * @ckdev: The keyboard device
572 *
573 * Returns 0 if no error or -error upon error.
574 */
575static int cros_ec_keyb_register_matrix(struct cros_ec_keyb *ckdev)
576{
577	struct cros_ec_device *ec_dev = ckdev->ec;
578	struct device *dev = ckdev->dev;
579	struct input_dev *idev;
580	const char *phys;
581	int err;
582
583	err = matrix_keypad_parse_properties(dev, &ckdev->rows, &ckdev->cols);
584	if (err)
585		return err;
586
587	ckdev->valid_keys = devm_kzalloc(dev, ckdev->cols, GFP_KERNEL);
588	if (!ckdev->valid_keys)
589		return -ENOMEM;
590
591	ckdev->old_kb_state = devm_kzalloc(dev, ckdev->cols, GFP_KERNEL);
592	if (!ckdev->old_kb_state)
593		return -ENOMEM;
594
595	/*
596	 * We call the keyboard matrix 'input0'. Allocate phys before input
597	 * dev, to ensure correct tear-down ordering.
598	 */
599	phys = devm_kasprintf(dev, GFP_KERNEL, "%s/input0", ec_dev->phys_name);
600	if (!phys)
601		return -ENOMEM;
602
603	idev = devm_input_allocate_device(dev);
604	if (!idev)
605		return -ENOMEM;
606
607	idev->name = CROS_EC_DEV_NAME;
608	idev->phys = phys;
609	__set_bit(EV_REP, idev->evbit);
610
611	idev->id.bustype = BUS_VIRTUAL;
612	idev->id.version = 1;
613	idev->id.product = 0;
614	idev->dev.parent = dev;
615
616	ckdev->ghost_filter = device_property_read_bool(dev,
617					"google,needs-ghost-filter");
618
619	err = matrix_keypad_build_keymap(NULL, NULL, ckdev->rows, ckdev->cols,
620					 NULL, idev);
621	if (err) {
622		dev_err(dev, "cannot build key matrix\n");
623		return err;
624	}
625
626	ckdev->row_shift = get_count_order(ckdev->cols);
627
628	input_set_capability(idev, EV_MSC, MSC_SCAN);
629	input_set_drvdata(idev, ckdev);
630	ckdev->idev = idev;
631	cros_ec_keyb_compute_valid_keys(ckdev);
632	cros_ec_keyb_parse_vivaldi_physmap(ckdev);
633
634	err = input_register_device(ckdev->idev);
635	if (err) {
636		dev_err(dev, "cannot register input device\n");
637		return err;
638	}
639
640	return 0;
641}
642
643static ssize_t function_row_physmap_show(struct device *dev,
644					 struct device_attribute *attr,
645					 char *buf)
646{
647	const struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
648	const struct vivaldi_data *data = &ckdev->vdata;
649
650	return vivaldi_function_row_physmap_show(data, buf);
651}
652
653static DEVICE_ATTR_RO(function_row_physmap);
654
655static struct attribute *cros_ec_keyb_attrs[] = {
656	&dev_attr_function_row_physmap.attr,
657	NULL,
658};
659
660static umode_t cros_ec_keyb_attr_is_visible(struct kobject *kobj,
661					    struct attribute *attr,
662					    int n)
663{
664	struct device *dev = kobj_to_dev(kobj);
665	struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
666
667	if (attr == &dev_attr_function_row_physmap.attr &&
668	    !ckdev->vdata.num_function_row_keys)
669		return 0;
670
671	return attr->mode;
672}
673
674static const struct attribute_group cros_ec_keyb_attr_group = {
675	.is_visible = cros_ec_keyb_attr_is_visible,
676	.attrs = cros_ec_keyb_attrs,
677};
 
678
679static int cros_ec_keyb_probe(struct platform_device *pdev)
680{
681	struct cros_ec_device *ec;
682	struct device *dev = &pdev->dev;
683	struct cros_ec_keyb *ckdev;
684	bool buttons_switches_only = device_get_match_data(dev);
685	int err;
686
687	/*
688	 * If the parent ec device has not been probed yet, defer the probe of
689	 * this keyboard/button driver until later.
690	 */
691	ec = dev_get_drvdata(pdev->dev.parent);
692	if (!ec)
693		return -EPROBE_DEFER;
694
695	ckdev = devm_kzalloc(dev, sizeof(*ckdev), GFP_KERNEL);
696	if (!ckdev)
697		return -ENOMEM;
698
699	ckdev->ec = ec;
700	ckdev->dev = dev;
701	dev_set_drvdata(dev, ckdev);
702
703	if (!buttons_switches_only) {
704		err = cros_ec_keyb_register_matrix(ckdev);
705		if (err) {
706			dev_err(dev, "cannot register matrix inputs: %d\n",
707				err);
708			return err;
709		}
710	}
711
712	err = cros_ec_keyb_register_bs(ckdev, buttons_switches_only);
713	if (err) {
714		dev_err(dev, "cannot register non-matrix inputs: %d\n", err);
715		return err;
716	}
717
718	err = devm_device_add_group(dev, &cros_ec_keyb_attr_group);
719	if (err) {
720		dev_err(dev, "failed to create attributes: %d\n", err);
721		return err;
722	}
723
724	ckdev->notifier.notifier_call = cros_ec_keyb_work;
725	err = blocking_notifier_chain_register(&ckdev->ec->event_notifier,
726					       &ckdev->notifier);
727	if (err) {
728		dev_err(dev, "cannot register notifier: %d\n", err);
729		return err;
730	}
731
732	device_init_wakeup(ckdev->dev, true);
733	return 0;
734}
735
736static int cros_ec_keyb_remove(struct platform_device *pdev)
737{
738	struct cros_ec_keyb *ckdev = dev_get_drvdata(&pdev->dev);
739
740	blocking_notifier_chain_unregister(&ckdev->ec->event_notifier,
741					   &ckdev->notifier);
742
743	return 0;
744}
745
746#ifdef CONFIG_ACPI
747static const struct acpi_device_id cros_ec_keyb_acpi_match[] = {
748	{ "GOOG0007", true },
749	{ }
750};
751MODULE_DEVICE_TABLE(acpi, cros_ec_keyb_acpi_match);
752#endif
753
754#ifdef CONFIG_OF
755static const struct of_device_id cros_ec_keyb_of_match[] = {
756	{ .compatible = "google,cros-ec-keyb" },
757	{ .compatible = "google,cros-ec-keyb-switches", .data = (void *)true },
758	{}
759};
760MODULE_DEVICE_TABLE(of, cros_ec_keyb_of_match);
761#endif
762
763static DEFINE_SIMPLE_DEV_PM_OPS(cros_ec_keyb_pm_ops, NULL, cros_ec_keyb_resume);
764
765static struct platform_driver cros_ec_keyb_driver = {
766	.probe = cros_ec_keyb_probe,
767	.remove = cros_ec_keyb_remove,
768	.driver = {
769		.name = "cros-ec-keyb",
 
770		.of_match_table = of_match_ptr(cros_ec_keyb_of_match),
771		.acpi_match_table = ACPI_PTR(cros_ec_keyb_acpi_match),
772		.pm = pm_sleep_ptr(&cros_ec_keyb_pm_ops),
773	},
774};
775
776module_platform_driver(cros_ec_keyb_driver);
777
778MODULE_LICENSE("GPL v2");
779MODULE_DESCRIPTION("ChromeOS EC keyboard driver");
780MODULE_ALIAS("platform:cros-ec-keyb");
v6.8
  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 */
 49struct 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 */
 78struct 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 */
 86static 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 */
137static 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 */
177static 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 */
227static 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
246static 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 */
312static 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 */
349static 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 */
406static 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 */
433static 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 */
459static 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
537static 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 */
590static 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
658static 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
668static DEVICE_ATTR_RO(function_row_physmap);
669
670static struct attribute *cros_ec_keyb_attrs[] = {
671	&dev_attr_function_row_physmap.attr,
672	NULL,
673};
674
675static 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
689static const struct attribute_group cros_ec_keyb_group = {
690	.is_visible = cros_ec_keyb_attr_is_visible,
691	.attrs = cros_ec_keyb_attrs,
692};
693__ATTRIBUTE_GROUPS(cros_ec_keyb);
694
695static int cros_ec_keyb_probe(struct platform_device *pdev)
696{
697	struct cros_ec_device *ec;
698	struct device *dev = &pdev->dev;
699	struct cros_ec_keyb *ckdev;
700	bool buttons_switches_only = device_get_match_data(dev);
701	int err;
702
703	/*
704	 * If the parent ec device has not been probed yet, defer the probe of
705	 * this keyboard/button driver until later.
706	 */
707	ec = dev_get_drvdata(pdev->dev.parent);
708	if (!ec)
709		return -EPROBE_DEFER;
710
711	ckdev = devm_kzalloc(dev, sizeof(*ckdev), GFP_KERNEL);
712	if (!ckdev)
713		return -ENOMEM;
714
715	ckdev->ec = ec;
716	ckdev->dev = dev;
717	dev_set_drvdata(dev, ckdev);
718
719	if (!buttons_switches_only) {
720		err = cros_ec_keyb_register_matrix(ckdev);
721		if (err) {
722			dev_err(dev, "cannot register matrix inputs: %d\n",
723				err);
724			return err;
725		}
726	}
727
728	err = cros_ec_keyb_register_bs(ckdev, buttons_switches_only);
729	if (err) {
730		dev_err(dev, "cannot register non-matrix inputs: %d\n", err);
731		return err;
732	}
733
 
 
 
 
 
 
734	ckdev->notifier.notifier_call = cros_ec_keyb_work;
735	err = blocking_notifier_chain_register(&ckdev->ec->event_notifier,
736					       &ckdev->notifier);
737	if (err) {
738		dev_err(dev, "cannot register notifier: %d\n", err);
739		return err;
740	}
741
742	device_init_wakeup(ckdev->dev, true);
743	return 0;
744}
745
746static void cros_ec_keyb_remove(struct platform_device *pdev)
747{
748	struct cros_ec_keyb *ckdev = dev_get_drvdata(&pdev->dev);
749
750	blocking_notifier_chain_unregister(&ckdev->ec->event_notifier,
751					   &ckdev->notifier);
 
 
752}
753
754#ifdef CONFIG_ACPI
755static const struct acpi_device_id cros_ec_keyb_acpi_match[] = {
756	{ "GOOG0007", true },
757	{ }
758};
759MODULE_DEVICE_TABLE(acpi, cros_ec_keyb_acpi_match);
760#endif
761
762#ifdef CONFIG_OF
763static const struct of_device_id cros_ec_keyb_of_match[] = {
764	{ .compatible = "google,cros-ec-keyb" },
765	{ .compatible = "google,cros-ec-keyb-switches", .data = (void *)true },
766	{}
767};
768MODULE_DEVICE_TABLE(of, cros_ec_keyb_of_match);
769#endif
770
771static DEFINE_SIMPLE_DEV_PM_OPS(cros_ec_keyb_pm_ops, NULL, cros_ec_keyb_resume);
772
773static struct platform_driver cros_ec_keyb_driver = {
774	.probe = cros_ec_keyb_probe,
775	.remove_new = cros_ec_keyb_remove,
776	.driver = {
777		.name = "cros-ec-keyb",
778		.dev_groups = cros_ec_keyb_groups,
779		.of_match_table = of_match_ptr(cros_ec_keyb_of_match),
780		.acpi_match_table = ACPI_PTR(cros_ec_keyb_acpi_match),
781		.pm = pm_sleep_ptr(&cros_ec_keyb_pm_ops),
782	},
783};
784
785module_platform_driver(cros_ec_keyb_driver);
786
787MODULE_LICENSE("GPL v2");
788MODULE_DESCRIPTION("ChromeOS EC keyboard driver");
789MODULE_ALIAS("platform:cros-ec-keyb");