xref: /linux/drivers/hid/hid-appletb-kbd.c (revision 1f988d0788f50d8464f957e793fab356e2937369)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Apple Touch Bar Keyboard Mode Driver
4  *
5  * Copyright (c) 2017-2018 Ronald Tschalär
6  * Copyright (c) 2022-2023 Kerem Karabay <kekrby@gmail.com>
7  * Copyright (c) 2024-2025 Aditya Garg <gargaditya08@live.com>
8  */
9 
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11 
12 #include <linux/hid.h>
13 #include <linux/usb.h>
14 #include <linux/input.h>
15 #include <linux/sysfs.h>
16 #include <linux/bitops.h>
17 #include <linux/module.h>
18 #include <linux/string.h>
19 #include <linux/backlight.h>
20 #include <linux/timer.h>
21 #include <linux/input/sparse-keymap.h>
22 
23 #include "hid-ids.h"
24 
25 #define APPLETB_KBD_MODE_ESC	0
26 #define APPLETB_KBD_MODE_FN	1
27 #define APPLETB_KBD_MODE_SPCL	2
28 #define APPLETB_KBD_MODE_OFF	3
29 #define APPLETB_KBD_MODE_MAX	APPLETB_KBD_MODE_OFF
30 
31 #define APPLETB_DEVID_KEYBOARD	1
32 #define APPLETB_DEVID_TRACKPAD	2
33 
34 #define HID_USAGE_MODE		0x00ff0004
35 
36 static int appletb_tb_def_mode = APPLETB_KBD_MODE_SPCL;
37 module_param_named(mode, appletb_tb_def_mode, int, 0444);
38 MODULE_PARM_DESC(mode, "Default touchbar mode:\n"
39 			 "    0 - escape key only\n"
40 			 "    1 - function-keys\n"
41 			 "    [2] - special keys");
42 
43 static bool appletb_tb_fn_toggle = true;
44 module_param_named(fntoggle, appletb_tb_fn_toggle, bool, 0644);
45 MODULE_PARM_DESC(fntoggle, "Switch between Fn and media controls on pressing Fn key");
46 
47 static bool appletb_tb_autodim = true;
48 module_param_named(autodim, appletb_tb_autodim, bool, 0644);
49 MODULE_PARM_DESC(autodim, "Automatically dim and turn off the Touch Bar after some time");
50 
51 static int appletb_tb_dim_timeout = 60;
52 module_param_named(dim_timeout, appletb_tb_dim_timeout, int, 0644);
53 MODULE_PARM_DESC(dim_timeout, "Dim timeout in sec");
54 
55 static int appletb_tb_idle_timeout = 15;
56 module_param_named(idle_timeout, appletb_tb_idle_timeout, int, 0644);
57 MODULE_PARM_DESC(idle_timeout, "Idle timeout in sec");
58 
59 struct appletb_kbd {
60 	struct hid_field *mode_field;
61 	struct input_handler inp_handler;
62 	struct input_handle kbd_handle;
63 	struct input_handle tpd_handle;
64 	struct backlight_device *backlight_dev;
65 	struct timer_list inactivity_timer;
66 	bool has_dimmed;
67 	bool has_turned_off;
68 	u8 saved_mode;
69 	u8 current_mode;
70 };
71 
72 static const struct key_entry appletb_kbd_keymap[] = {
73 	{ KE_KEY, KEY_ESC, { KEY_ESC } },
74 	{ KE_KEY, KEY_F1,  { KEY_BRIGHTNESSDOWN } },
75 	{ KE_KEY, KEY_F2,  { KEY_BRIGHTNESSUP } },
76 	{ KE_KEY, KEY_F3,  { KEY_RESERVED } },
77 	{ KE_KEY, KEY_F4,  { KEY_RESERVED } },
78 	{ KE_KEY, KEY_F5,  { KEY_KBDILLUMDOWN } },
79 	{ KE_KEY, KEY_F6,  { KEY_KBDILLUMUP } },
80 	{ KE_KEY, KEY_F7,  { KEY_PREVIOUSSONG } },
81 	{ KE_KEY, KEY_F8,  { KEY_PLAYPAUSE } },
82 	{ KE_KEY, KEY_F9,  { KEY_NEXTSONG } },
83 	{ KE_KEY, KEY_F10, { KEY_MUTE } },
84 	{ KE_KEY, KEY_F11, { KEY_VOLUMEDOWN } },
85 	{ KE_KEY, KEY_F12, { KEY_VOLUMEUP } },
86 	{ KE_END, 0 }
87 };
88 
appletb_kbd_set_mode(struct appletb_kbd * kbd,u8 mode)89 static int appletb_kbd_set_mode(struct appletb_kbd *kbd, u8 mode)
90 {
91 	struct hid_report *report = kbd->mode_field->report;
92 	struct hid_device *hdev = report->device;
93 	int ret;
94 
95 	ret = hid_hw_power(hdev, PM_HINT_FULLON);
96 	if (ret) {
97 		hid_err(hdev, "Device didn't resume (%pe)\n", ERR_PTR(ret));
98 		return ret;
99 	}
100 
101 	ret = hid_set_field(kbd->mode_field, 0, mode);
102 	if (ret) {
103 		hid_err(hdev, "Failed to set mode field to %u (%pe)\n", mode, ERR_PTR(ret));
104 		goto power_normal;
105 	}
106 
107 	hid_hw_request(hdev, report, HID_REQ_SET_REPORT);
108 
109 	kbd->current_mode = mode;
110 
111 power_normal:
112 	hid_hw_power(hdev, PM_HINT_NORMAL);
113 
114 	return ret;
115 }
116 
mode_show(struct device * dev,struct device_attribute * attr,char * buf)117 static ssize_t mode_show(struct device *dev,
118 			 struct device_attribute *attr, char *buf)
119 {
120 	struct appletb_kbd *kbd = dev_get_drvdata(dev);
121 
122 	return sysfs_emit(buf, "%d\n", kbd->current_mode);
123 }
124 
mode_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)125 static ssize_t mode_store(struct device *dev,
126 			  struct device_attribute *attr,
127 			  const char *buf, size_t size)
128 {
129 	struct appletb_kbd *kbd = dev_get_drvdata(dev);
130 	u8 mode;
131 	int ret;
132 
133 	ret = kstrtou8(buf, 0, &mode);
134 	if (ret)
135 		return ret;
136 
137 	if (mode > APPLETB_KBD_MODE_MAX)
138 		return -EINVAL;
139 
140 	ret = appletb_kbd_set_mode(kbd, mode);
141 
142 	return ret < 0 ? ret : size;
143 }
144 static DEVICE_ATTR_RW(mode);
145 
146 static struct attribute *appletb_kbd_attrs[] = {
147 	&dev_attr_mode.attr,
148 	NULL
149 };
150 ATTRIBUTE_GROUPS(appletb_kbd);
151 
appletb_tb_key_to_slot(unsigned int code)152 static int appletb_tb_key_to_slot(unsigned int code)
153 {
154 	switch (code) {
155 	case KEY_ESC:
156 		return 0;
157 	case KEY_F1 ... KEY_F10:
158 		return code - KEY_F1 + 1;
159 	case KEY_F11 ... KEY_F12:
160 		return code - KEY_F11 + 11;
161 
162 	default:
163 		return -EINVAL;
164 	}
165 }
166 
appletb_inactivity_timer(struct timer_list * t)167 static void appletb_inactivity_timer(struct timer_list *t)
168 {
169 	struct appletb_kbd *kbd = timer_container_of(kbd, t, inactivity_timer);
170 
171 	if (kbd->backlight_dev && appletb_tb_autodim) {
172 		if (!kbd->has_dimmed) {
173 			backlight_device_set_brightness(kbd->backlight_dev, 1);
174 			kbd->has_dimmed = true;
175 			mod_timer(&kbd->inactivity_timer,
176 				jiffies + secs_to_jiffies(appletb_tb_idle_timeout));
177 		} else if (!kbd->has_turned_off) {
178 			backlight_device_set_brightness(kbd->backlight_dev, 0);
179 			kbd->has_turned_off = true;
180 		}
181 	}
182 }
183 
reset_inactivity_timer(struct appletb_kbd * kbd)184 static void reset_inactivity_timer(struct appletb_kbd *kbd)
185 {
186 	if (kbd->backlight_dev && appletb_tb_autodim) {
187 		if (kbd->has_dimmed || kbd->has_turned_off) {
188 			backlight_device_set_brightness(kbd->backlight_dev, 2);
189 			kbd->has_dimmed = false;
190 			kbd->has_turned_off = false;
191 		}
192 		mod_timer(&kbd->inactivity_timer,
193 			jiffies + secs_to_jiffies(appletb_tb_dim_timeout));
194 	}
195 }
196 
appletb_kbd_hid_event(struct hid_device * hdev,struct hid_field * field,struct hid_usage * usage,__s32 value)197 static int appletb_kbd_hid_event(struct hid_device *hdev, struct hid_field *field,
198 				      struct hid_usage *usage, __s32 value)
199 {
200 	struct appletb_kbd *kbd = hid_get_drvdata(hdev);
201 	struct key_entry *translation;
202 	struct input_dev *input;
203 	int slot;
204 
205 	if ((usage->hid & HID_USAGE_PAGE) != HID_UP_KEYBOARD || usage->type != EV_KEY)
206 		return 0;
207 
208 	input = field->hidinput->input;
209 
210 	/*
211 	 * Skip non-touch-bar keys.
212 	 *
213 	 * Either the touch bar itself or usbhid generate a slew of key-down
214 	 * events for all the meta keys. None of which we're at all interested
215 	 * in.
216 	 */
217 	slot = appletb_tb_key_to_slot(usage->code);
218 	if (slot < 0)
219 		return 0;
220 
221 	reset_inactivity_timer(kbd);
222 
223 	translation = sparse_keymap_entry_from_scancode(input, usage->code);
224 
225 	if (translation && kbd->current_mode == APPLETB_KBD_MODE_SPCL) {
226 		input_event(input, usage->type, translation->keycode, value);
227 
228 		return 1;
229 	}
230 
231 	return kbd->current_mode == APPLETB_KBD_MODE_OFF;
232 }
233 
appletb_kbd_inp_event(struct input_handle * handle,unsigned int type,unsigned int code,int value)234 static void appletb_kbd_inp_event(struct input_handle *handle, unsigned int type,
235 			      unsigned int code, int value)
236 {
237 	struct appletb_kbd *kbd = handle->private;
238 
239 	reset_inactivity_timer(kbd);
240 
241 	if (type == EV_KEY && code == KEY_FN && appletb_tb_fn_toggle &&
242 		(kbd->current_mode == APPLETB_KBD_MODE_SPCL ||
243 		 kbd->current_mode == APPLETB_KBD_MODE_FN)) {
244 		if (value == 1) {
245 			kbd->saved_mode = kbd->current_mode;
246 			appletb_kbd_set_mode(kbd, kbd->current_mode == APPLETB_KBD_MODE_SPCL
247 						? APPLETB_KBD_MODE_FN : APPLETB_KBD_MODE_SPCL);
248 		} else if (value == 0) {
249 			if (kbd->saved_mode != kbd->current_mode)
250 				appletb_kbd_set_mode(kbd, kbd->saved_mode);
251 		}
252 	}
253 }
254 
appletb_kbd_inp_connect(struct input_handler * handler,struct input_dev * dev,const struct input_device_id * id)255 static int appletb_kbd_inp_connect(struct input_handler *handler,
256 			       struct input_dev *dev,
257 			       const struct input_device_id *id)
258 {
259 	struct appletb_kbd *kbd = handler->private;
260 	struct input_handle *handle;
261 	int rc;
262 
263 	if (id->driver_info == APPLETB_DEVID_KEYBOARD) {
264 		handle = &kbd->kbd_handle;
265 		handle->name = "tbkbd";
266 	} else if (id->driver_info == APPLETB_DEVID_TRACKPAD) {
267 		handle = &kbd->tpd_handle;
268 		handle->name = "tbtpd";
269 	} else {
270 		return -ENOENT;
271 	}
272 
273 	if (handle->dev)
274 		return -EEXIST;
275 
276 	handle->open = 0;
277 	handle->dev = input_get_device(dev);
278 	handle->handler = handler;
279 	handle->private = kbd;
280 
281 	rc = input_register_handle(handle);
282 	if (rc)
283 		goto err_free_dev;
284 
285 	rc = input_open_device(handle);
286 	if (rc)
287 		goto err_unregister_handle;
288 
289 	return 0;
290 
291  err_unregister_handle:
292 	input_unregister_handle(handle);
293  err_free_dev:
294 	input_put_device(handle->dev);
295 	handle->dev = NULL;
296 	return rc;
297 }
298 
appletb_kbd_inp_disconnect(struct input_handle * handle)299 static void appletb_kbd_inp_disconnect(struct input_handle *handle)
300 {
301 	input_close_device(handle);
302 	input_unregister_handle(handle);
303 
304 	input_put_device(handle->dev);
305 	handle->dev = NULL;
306 }
307 
appletb_kbd_input_configured(struct hid_device * hdev,struct hid_input * hidinput)308 static int appletb_kbd_input_configured(struct hid_device *hdev, struct hid_input *hidinput)
309 {
310 	int idx;
311 	struct input_dev *input = hidinput->input;
312 
313 	/*
314 	 * Clear various input capabilities that are blindly set by the hid
315 	 * driver (usbkbd.c)
316 	 */
317 	memset(input->evbit, 0, sizeof(input->evbit));
318 	memset(input->keybit, 0, sizeof(input->keybit));
319 	memset(input->ledbit, 0, sizeof(input->ledbit));
320 
321 	__set_bit(EV_REP, input->evbit);
322 
323 	sparse_keymap_setup(input, appletb_kbd_keymap, NULL);
324 
325 	for (idx = 0; appletb_kbd_keymap[idx].type != KE_END; idx++)
326 		input_set_capability(input, EV_KEY, appletb_kbd_keymap[idx].code);
327 
328 	return 0;
329 }
330 
331 static const struct input_device_id appletb_kbd_input_devices[] = {
332 	{
333 		.flags = INPUT_DEVICE_ID_MATCH_BUS |
334 			INPUT_DEVICE_ID_MATCH_VENDOR |
335 			INPUT_DEVICE_ID_MATCH_KEYBIT,
336 		.bustype = BUS_USB,
337 		.vendor = USB_VENDOR_ID_APPLE,
338 		.keybit = { [BIT_WORD(KEY_FN)] = BIT_MASK(KEY_FN) },
339 		.driver_info = APPLETB_DEVID_KEYBOARD,
340 	},
341 	{
342 		.flags = INPUT_DEVICE_ID_MATCH_BUS |
343 			INPUT_DEVICE_ID_MATCH_VENDOR |
344 			INPUT_DEVICE_ID_MATCH_KEYBIT,
345 		.bustype = BUS_USB,
346 		.vendor = USB_VENDOR_ID_APPLE,
347 		.keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
348 		.driver_info = APPLETB_DEVID_TRACKPAD,
349 	},
350 	{ }
351 };
352 
appletb_kbd_match_internal_device(struct input_handler * handler,struct input_dev * inp_dev)353 static bool appletb_kbd_match_internal_device(struct input_handler *handler,
354 					  struct input_dev *inp_dev)
355 {
356 	struct device *dev = &inp_dev->dev;
357 
358 	/* in kernel: dev && !is_usb_device(dev) */
359 	while (dev && !(dev->type && dev->type->name &&
360 			!strcmp(dev->type->name, "usb_device")))
361 		dev = dev->parent;
362 
363 	/*
364 	 * Apple labels all their internal keyboards and trackpads as such,
365 	 * instead of maintaining an ever expanding list of product-id's we
366 	 * just look at the device's product name.
367 	 */
368 	if (dev)
369 		return !!strstr(to_usb_device(dev)->product, "Internal Keyboard");
370 
371 	return false;
372 }
373 
appletb_kbd_probe(struct hid_device * hdev,const struct hid_device_id * id)374 static int appletb_kbd_probe(struct hid_device *hdev, const struct hid_device_id *id)
375 {
376 	struct appletb_kbd *kbd;
377 	struct device *dev = &hdev->dev;
378 	struct hid_field *mode_field;
379 	int ret;
380 
381 	ret = hid_parse(hdev);
382 	if (ret)
383 		return dev_err_probe(dev, ret, "HID parse failed\n");
384 
385 	mode_field = hid_find_field(hdev, HID_OUTPUT_REPORT,
386 				    HID_GD_KEYBOARD, HID_USAGE_MODE);
387 	if (!mode_field)
388 		return -ENODEV;
389 
390 	kbd = devm_kzalloc(dev, sizeof(*kbd), GFP_KERNEL);
391 	if (!kbd)
392 		return -ENOMEM;
393 
394 	kbd->mode_field = mode_field;
395 
396 	ret = hid_hw_start(hdev, HID_CONNECT_HIDINPUT);
397 	if (ret)
398 		return dev_err_probe(dev, ret, "HID hw start failed\n");
399 
400 	ret = hid_hw_open(hdev);
401 	if (ret) {
402 		dev_err_probe(dev, ret, "HID hw open failed\n");
403 		goto stop_hw;
404 	}
405 
406 	kbd->backlight_dev = backlight_device_get_by_name("appletb_backlight");
407 	if (!kbd->backlight_dev) {
408 		dev_err_probe(dev, -ENODEV, "Failed to get backlight device\n");
409 	} else {
410 		backlight_device_set_brightness(kbd->backlight_dev, 2);
411 		timer_setup(&kbd->inactivity_timer, appletb_inactivity_timer, 0);
412 		mod_timer(&kbd->inactivity_timer,
413 			jiffies + secs_to_jiffies(appletb_tb_dim_timeout));
414 	}
415 
416 	kbd->inp_handler.event = appletb_kbd_inp_event;
417 	kbd->inp_handler.connect = appletb_kbd_inp_connect;
418 	kbd->inp_handler.disconnect = appletb_kbd_inp_disconnect;
419 	kbd->inp_handler.name = "appletb";
420 	kbd->inp_handler.id_table = appletb_kbd_input_devices;
421 	kbd->inp_handler.match = appletb_kbd_match_internal_device;
422 	kbd->inp_handler.private = kbd;
423 
424 	ret = input_register_handler(&kbd->inp_handler);
425 	if (ret) {
426 		dev_err_probe(dev, ret, "Unable to register keyboard handler\n");
427 		goto close_hw;
428 	}
429 
430 	ret = appletb_kbd_set_mode(kbd, appletb_tb_def_mode);
431 	if (ret) {
432 		dev_err_probe(dev, ret, "Failed to set touchbar mode\n");
433 		goto unregister_handler;
434 	}
435 
436 	hid_set_drvdata(hdev, kbd);
437 
438 	return 0;
439 
440 unregister_handler:
441 	input_unregister_handler(&kbd->inp_handler);
442 close_hw:
443 	if (kbd->backlight_dev) {
444 		put_device(&kbd->backlight_dev->dev);
445 		timer_delete_sync(&kbd->inactivity_timer);
446 	}
447 	hid_hw_close(hdev);
448 stop_hw:
449 	hid_hw_stop(hdev);
450 	return ret;
451 }
452 
appletb_kbd_remove(struct hid_device * hdev)453 static void appletb_kbd_remove(struct hid_device *hdev)
454 {
455 	struct appletb_kbd *kbd = hid_get_drvdata(hdev);
456 
457 	appletb_kbd_set_mode(kbd, APPLETB_KBD_MODE_OFF);
458 
459 	input_unregister_handler(&kbd->inp_handler);
460 	if (kbd->backlight_dev) {
461 		put_device(&kbd->backlight_dev->dev);
462 		timer_delete_sync(&kbd->inactivity_timer);
463 	}
464 
465 	hid_hw_close(hdev);
466 	hid_hw_stop(hdev);
467 }
468 
469 #ifdef CONFIG_PM
appletb_kbd_suspend(struct hid_device * hdev,pm_message_t msg)470 static int appletb_kbd_suspend(struct hid_device *hdev, pm_message_t msg)
471 {
472 	struct appletb_kbd *kbd = hid_get_drvdata(hdev);
473 
474 	kbd->saved_mode = kbd->current_mode;
475 	appletb_kbd_set_mode(kbd, APPLETB_KBD_MODE_OFF);
476 
477 	return 0;
478 }
479 
appletb_kbd_reset_resume(struct hid_device * hdev)480 static int appletb_kbd_reset_resume(struct hid_device *hdev)
481 {
482 	struct appletb_kbd *kbd = hid_get_drvdata(hdev);
483 
484 	appletb_kbd_set_mode(kbd, kbd->saved_mode);
485 
486 	return 0;
487 }
488 #endif
489 
490 static const struct hid_device_id appletb_kbd_hid_ids[] = {
491 	/* MacBook Pro's 2018, 2019, with T2 chip: iBridge Display */
492 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_TOUCHBAR_DISPLAY) },
493 	{ }
494 };
495 MODULE_DEVICE_TABLE(hid, appletb_kbd_hid_ids);
496 
497 static struct hid_driver appletb_kbd_hid_driver = {
498 	.name = "hid-appletb-kbd",
499 	.id_table = appletb_kbd_hid_ids,
500 	.probe = appletb_kbd_probe,
501 	.remove = appletb_kbd_remove,
502 	.event = appletb_kbd_hid_event,
503 	.input_configured = appletb_kbd_input_configured,
504 #ifdef CONFIG_PM
505 	.suspend = appletb_kbd_suspend,
506 	.reset_resume = appletb_kbd_reset_resume,
507 #endif
508 	.driver.dev_groups = appletb_kbd_groups,
509 };
510 module_hid_driver(appletb_kbd_hid_driver);
511 
512 /* The backlight driver should be loaded before the keyboard driver is initialised */
513 MODULE_SOFTDEP("pre: hid_appletb_bl");
514 
515 MODULE_AUTHOR("Ronald Tschalär");
516 MODULE_AUTHOR("Kerem Karabay <kekrby@gmail.com>");
517 MODULE_AUTHOR("Aditya Garg <gargaditya08@live.com>");
518 MODULE_DESCRIPTION("MacBook Pro Touch Bar Keyboard Mode driver");
519 MODULE_LICENSE("GPL");
520