1 // SPDX-License-Identifier: GPL-2.0
2 // ChromeOS EC keyboard driver
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,
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
16 #include <linux/i2c.h>
35  * @ghost_filter: true to enable the matrix key-ghosting filter
39  * @ec: Top level ChromeOS device to use to talk to EC
41  * @bs_idev: The input device for non-matrix buttons and switches (or NULL).
54 	struct cros_ec_device *ec;  member
63  * cros_ec_bs_map - Struct mapping Linux keycodes to EC button/switch bitmap
79 /* cros_ec_keyb_bs - Map EC button/switch #defines into kernel ones */
119 	struct device *dev = ckdev->dev;  in cros_ec_keyb_has_ghosting()
120 	uint8_t *valid_keys = ckdev->valid_keys;  in cros_ec_keyb_has_ghosting()
135 	for (col1 = 0; col1 < ckdev->cols; col1++) {  in cros_ec_keyb_has_ghosting()
137 		for (col2 = col1 + 1; col2 < ckdev->cols; col2++) {  in cros_ec_keyb_has_ghosting()
159 	struct input_dev *idev = ckdev->idev;  in cros_ec_keyb_process()
164 	if (ckdev->ghost_filter && cros_ec_keyb_has_ghosting(ckdev, kb_state)) {  in cros_ec_keyb_process()
166 		 * Simple-minded solution: ignore this state. The obvious  in cros_ec_keyb_process()
170 		dev_dbg(ckdev->dev, "ghosting found\n");  in cros_ec_keyb_process()
174 	for (col = 0; col < ckdev->cols; col++) {  in cros_ec_keyb_process()
175 		for (row = 0; row < ckdev->rows; row++) {  in cros_ec_keyb_process()
176 			int pos = MATRIX_SCAN_CODE(row, col, ckdev->row_shift);  in cros_ec_keyb_process()
177 			const unsigned short *keycodes = idev->keycode;  in cros_ec_keyb_process()
180 			old_state = ckdev->old_kb_state[col] & (1 << row);  in cros_ec_keyb_process()
182 				dev_dbg(ckdev->dev,  in cros_ec_keyb_process()
191 		ckdev->old_kb_state[col] = kb_state[col];  in cros_ec_keyb_process()
193 	input_sync(ckdev->idev);  in cros_ec_keyb_process()
197  * cros_ec_keyb_report_bs - Report non-matrixed buttons or switches
199  * This takes a bitmap of buttons or switches from the EC and reports events,
204  * @mask: A bitmap of buttons from the EC.
210 	struct input_dev *idev = ckdev->bs_idev;  in cros_ec_keyb_report_bs()
216 		if (map->ev_type != ev_type)  in cros_ec_keyb_report_bs()
219 		input_event(idev, ev_type, map->code,  in cros_ec_keyb_report_bs()
220 			    !!(mask & BIT(map->bit)) ^ map->inverted);  in cros_ec_keyb_report_bs()
235 	 * suspend. Switches will be re-checked in  in cros_ec_keyb_work()
238 	if (queued_during_suspend && !device_may_wakeup(ckdev->dev))  in cros_ec_keyb_work()
241 	switch (ckdev->ec->event_data.event_type) {  in cros_ec_keyb_work()
243 		pm_wakeup_event(ckdev->dev, 0);  in cros_ec_keyb_work()
245 		if (ckdev->ec->event_size != ckdev->cols) {  in cros_ec_keyb_work()
246 			dev_err(ckdev->dev,  in cros_ec_keyb_work()
252 				     ckdev->ec->event_data.data.key_matrix,  in cros_ec_keyb_work()
253 				     ckdev->ec->event_size);  in cros_ec_keyb_work()
257 		pm_wakeup_event(ckdev->dev, 0);  in cros_ec_keyb_work()
259 		val = get_unaligned_le32(&ckdev->ec->event_data.data.sysrq);  in cros_ec_keyb_work()
260 		dev_dbg(ckdev->dev, "sysrq code from EC: %#x\n", val);  in cros_ec_keyb_work()
266 		pm_wakeup_event(ckdev->dev, 0);  in cros_ec_keyb_work()
268 		if (ckdev->ec->event_data.event_type == EC_MKBP_EVENT_BUTTON) {  in cros_ec_keyb_work()
270 					&ckdev->ec->event_data.data.buttons);  in cros_ec_keyb_work()
274 					&ckdev->ec->event_data.data.switches);  in cros_ec_keyb_work()
294 	int row_shift = ckdev->row_shift;  in cros_ec_keyb_compute_valid_keys()
295 	unsigned short *keymap = ckdev->idev->keycode;  in cros_ec_keyb_compute_valid_keys()
298 	BUG_ON(ckdev->idev->keycodesize != sizeof(*keymap));  in cros_ec_keyb_compute_valid_keys()
300 	for (col = 0; col < ckdev->cols; col++) {  in cros_ec_keyb_compute_valid_keys()
301 		for (row = 0; row < ckdev->rows; row++) {  in cros_ec_keyb_compute_valid_keys()
304 				ckdev->valid_keys[col] |= 1 << row;  in cros_ec_keyb_compute_valid_keys()
306 		dev_dbg(ckdev->dev, "valid_keys[%02d] = 0x%02x\n",  in cros_ec_keyb_compute_valid_keys()
307 			col, ckdev->valid_keys[col]);  in cros_ec_keyb_compute_valid_keys()
312  * cros_ec_keyb_info - Wrap the EC command EC_CMD_MKBP_INFO
317  * @ec_dev: The EC device
326  * Returns 0 if no error or -error upon error.
341 		return -ENOMEM;  in cros_ec_keyb_info()
343 	msg->command = EC_CMD_MKBP_INFO;  in cros_ec_keyb_info()
344 	msg->version = 1;  in cros_ec_keyb_info()
345 	msg->outsize = sizeof(*params);  in cros_ec_keyb_info()
346 	msg->insize = result_size;  in cros_ec_keyb_info()
347 	params = (struct ec_params_mkbp_info *)msg->data;  in cros_ec_keyb_info()
348 	params->info_type = info_type;  in cros_ec_keyb_info()
349 	params->event_type = event_type;  in cros_ec_keyb_info()
352 	if (ret == -ENOPROTOOPT) {  in cros_ec_keyb_info()
357 		dev_warn(ec_dev->dev, "Transfer error %d/%d: %d\n",  in cros_ec_keyb_info()
360 		dev_warn(ec_dev->dev, "Wrong size %d/%d: %d != %zu\n",  in cros_ec_keyb_info()
363 		ret = -EPROTO;  in cros_ec_keyb_info()
365 		memcpy(result, msg->data, result_size);  in cros_ec_keyb_info()
375  * cros_ec_keyb_query_switches - Query the state of switches and report
377  * This will ask the EC about the current state of switches and report to the
383  * Returns 0 if no error or -error upon error.
387 	struct cros_ec_device *ec_dev = ckdev->ec;  in cros_ec_keyb_query_switches()
404  * cros_ec_keyb_resume - Resume the keyboard
406  * We use the resume notification as a chance to query the EC for switches.
410  * Returns 0 if no error or -error upon error.
416 	if (ckdev->bs_idev)  in cros_ec_keyb_resume()
423  * cros_ec_keyb_register_bs - Register non-matrix buttons/switches
425  * Handles all the bits of the keyboard driver related to non-matrix buttons
426  * and switches, including asking the EC about which are present and telling
430  * but the ckdev->bs_idev will remain NULL when this function exits.
434  * Returns 0 if no error or -error upon error.
438 	struct cros_ec_device *ec_dev = ckdev->ec;  in cros_ec_keyb_register_bs()
439 	struct device *dev = ckdev->dev;  in cros_ec_keyb_register_bs()
466 	 * We call the non-matrix buttons/switches 'input1', if present.  in cros_ec_keyb_register_bs()
467 	 * Allocate phys before input dev, to ensure correct tear-down  in cros_ec_keyb_register_bs()
470 	phys = devm_kasprintf(dev, GFP_KERNEL, "%s/input1", ec_dev->phys_name);  in cros_ec_keyb_register_bs()
472 		return -ENOMEM;  in cros_ec_keyb_register_bs()
476 		return -ENOMEM;  in cros_ec_keyb_register_bs()
478 	idev->name = "cros_ec_buttons";  in cros_ec_keyb_register_bs()
479 	idev->phys = phys;  in cros_ec_keyb_register_bs()
480 	__set_bit(EV_REP, idev->evbit);  in cros_ec_keyb_register_bs()
482 	idev->id.bustype = BUS_VIRTUAL;  in cros_ec_keyb_register_bs()
483 	idev->id.version = 1;  in cros_ec_keyb_register_bs()
484 	idev->id.product = 0;  in cros_ec_keyb_register_bs()
485 	idev->dev.parent = dev;  in cros_ec_keyb_register_bs()
488 	ckdev->bs_idev = idev;  in cros_ec_keyb_register_bs()
493 		if ((map->ev_type == EV_KEY && (buttons & BIT(map->bit))) ||  in cros_ec_keyb_register_bs()
494 		    (map->ev_type == EV_SW && (switches & BIT(map->bit))))  in cros_ec_keyb_register_bs()
495 			input_set_capability(idev, map->ev_type, map->code);  in cros_ec_keyb_register_bs()
504 	ret = input_register_device(ckdev->bs_idev);  in cros_ec_keyb_register_bs()
514  * cros_ec_keyb_register_bs - Register matrix keys
520  * Returns 0 if no error or -error upon error.
524 	struct cros_ec_device *ec_dev = ckdev->ec;  in cros_ec_keyb_register_matrix()
525 	struct device *dev = ckdev->dev;  in cros_ec_keyb_register_matrix()
530 	err = matrix_keypad_parse_properties(dev, &ckdev->rows, &ckdev->cols);  in cros_ec_keyb_register_matrix()
534 	ckdev->valid_keys = devm_kzalloc(dev, ckdev->cols, GFP_KERNEL);  in cros_ec_keyb_register_matrix()
535 	if (!ckdev->valid_keys)  in cros_ec_keyb_register_matrix()
536 		return -ENOMEM;  in cros_ec_keyb_register_matrix()
538 	ckdev->old_kb_state = devm_kzalloc(dev, ckdev->cols, GFP_KERNEL);  in cros_ec_keyb_register_matrix()
539 	if (!ckdev->old_kb_state)  in cros_ec_keyb_register_matrix()
540 		return -ENOMEM;  in cros_ec_keyb_register_matrix()
544 	 * dev, to ensure correct tear-down ordering.  in cros_ec_keyb_register_matrix()
546 	phys = devm_kasprintf(dev, GFP_KERNEL, "%s/input0", ec_dev->phys_name);  in cros_ec_keyb_register_matrix()
548 		return -ENOMEM;  in cros_ec_keyb_register_matrix()
552 		return -ENOMEM;  in cros_ec_keyb_register_matrix()
554 	idev->name = CROS_EC_DEV_NAME;  in cros_ec_keyb_register_matrix()
555 	idev->phys = phys;  in cros_ec_keyb_register_matrix()
556 	__set_bit(EV_REP, idev->evbit);  in cros_ec_keyb_register_matrix()
558 	idev->id.bustype = BUS_VIRTUAL;  in cros_ec_keyb_register_matrix()
559 	idev->id.version = 1;  in cros_ec_keyb_register_matrix()
560 	idev->id.product = 0;  in cros_ec_keyb_register_matrix()
561 	idev->dev.parent = dev;  in cros_ec_keyb_register_matrix()
563 	ckdev->ghost_filter = of_property_read_bool(dev->of_node,  in cros_ec_keyb_register_matrix()
564 					"google,needs-ghost-filter");  in cros_ec_keyb_register_matrix()
566 	err = matrix_keypad_build_keymap(NULL, NULL, ckdev->rows, ckdev->cols,  in cros_ec_keyb_register_matrix()
573 	ckdev->row_shift = get_count_order(ckdev->cols);  in cros_ec_keyb_register_matrix()
577 	ckdev->idev = idev;  in cros_ec_keyb_register_matrix()
580 	err = input_register_device(ckdev->idev);  in cros_ec_keyb_register_matrix()
591 	struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent);  in cros_ec_keyb_probe()  local
592 	struct device *dev = &pdev->dev;  in cros_ec_keyb_probe()
596 	if (!dev->of_node)  in cros_ec_keyb_probe()
597 		return -ENODEV;  in cros_ec_keyb_probe()
601 		return -ENOMEM;  in cros_ec_keyb_probe()
603 	ckdev->ec = ec;  in cros_ec_keyb_probe()
604 	ckdev->dev = dev;  in cros_ec_keyb_probe()
615 		dev_err(dev, "cannot register non-matrix inputs: %d\n", err);  in cros_ec_keyb_probe()
619 	ckdev->notifier.notifier_call = cros_ec_keyb_work;  in cros_ec_keyb_probe()
620 	err = blocking_notifier_chain_register(&ckdev->ec->event_notifier,  in cros_ec_keyb_probe()
621 					       &ckdev->notifier);  in cros_ec_keyb_probe()
627 	device_init_wakeup(ckdev->dev, true);  in cros_ec_keyb_probe()
633 	struct cros_ec_keyb *ckdev = dev_get_drvdata(&pdev->dev);  in cros_ec_keyb_remove()
635 	blocking_notifier_chain_unregister(&ckdev->ec->event_notifier,  in cros_ec_keyb_remove()
636 					   &ckdev->notifier);  in cros_ec_keyb_remove()
643 	{ .compatible = "google,cros-ec-keyb" },
655 		.name = "cros-ec-keyb",
664 MODULE_DESCRIPTION("ChromeOS EC keyboard driver");
665 MODULE_ALIAS("platform:cros-ec-keyb");