1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * This is a driver for the keyboard, touchpad and USB port of the
4  * keyboard dock for the Asus TF103C 2-in-1 tablet.
5  *
6  * This keyboard dock has its own I2C attached embedded controller
7  * and the keyboard and touchpad are also connected over I2C,
8  * instead of using the usual USB connection. This means that the
9  * keyboard dock requires this special driver to function.
10  *
11  * Copyright (C) 2021 Hans de Goede <hdegoede@redhat.com>
12  */
13 
14 #include <linux/acpi.h>
15 #include <linux/delay.h>
16 #include <linux/dmi.h>
17 #include <linux/gpio/consumer.h>
18 #include <linux/gpio/machine.h>
19 #include <linux/hid.h>
20 #include <linux/i2c.h>
21 #include <linux/input.h>
22 #include <linux/irq.h>
23 #include <linux/irqdomain.h>
24 #include <linux/mod_devicetable.h>
25 #include <linux/moduleparam.h>
26 #include <linux/module.h>
27 #include <linux/pm.h>
28 #include <linux/workqueue.h>
29 #include <asm/unaligned.h>
30 
31 static bool fnlock;
32 module_param(fnlock, bool, 0644);
33 MODULE_PARM_DESC(fnlock,
34 		 "By default the kbd toprow sends multimedia key presses. AltGr "
35 		 "can be pressed to change this to F1-F12. Set this to 1 to "
36 		 "change the default. Press AltGr + Esc to toggle at runtime.");
37 
38 #define TF103C_DOCK_DEV_NAME				"NPCE69A:00"
39 
40 #define TF103C_DOCK_HPD_DEBOUNCE			msecs_to_jiffies(20)
41 
42 /*** Touchpad I2C device defines ***/
43 #define TF103C_DOCK_TP_ADDR				0x15
44 
45 /*** Keyboard I2C device defines **A*/
46 #define TF103C_DOCK_KBD_ADDR				0x16
47 
48 #define TF103C_DOCK_KBD_DATA_REG			0x73
49 #define TF103C_DOCK_KBD_DATA_MIN_LENGTH			4
50 #define TF103C_DOCK_KBD_DATA_MAX_LENGTH			11
51 #define TF103C_DOCK_KBD_DATA_MODIFIERS			3
52 #define TF103C_DOCK_KBD_DATA_KEYS			5
53 #define TF103C_DOCK_KBD_CMD_REG				0x75
54 
55 #define TF103C_DOCK_KBD_CMD_ENABLE			0x0800
56 
57 /*** EC innterrupt data I2C device defines ***/
58 #define TF103C_DOCK_INTR_ADDR				0x19
59 #define TF103C_DOCK_INTR_DATA_REG			0x6a
60 
61 #define TF103C_DOCK_INTR_DATA1_OBF_MASK			0x01
62 #define TF103C_DOCK_INTR_DATA1_KEY_MASK			0x04
63 #define TF103C_DOCK_INTR_DATA1_KBC_MASK			0x08
64 #define TF103C_DOCK_INTR_DATA1_AUX_MASK			0x20
65 #define TF103C_DOCK_INTR_DATA1_SCI_MASK			0x40
66 #define TF103C_DOCK_INTR_DATA1_SMI_MASK			0x80
67 /* Special values for the OOB data on kbd_client / tp_client */
68 #define TF103C_DOCK_INTR_DATA1_OOB_VALUE		0xc1
69 #define TF103C_DOCK_INTR_DATA2_OOB_VALUE		0x04
70 
71 #define TF103C_DOCK_SMI_AC_EVENT			0x31
72 #define TF103C_DOCK_SMI_HANDSHAKING			0x50
73 #define TF103C_DOCK_SMI_EC_WAKEUP			0x53
74 #define TF103C_DOCK_SMI_BOOTBLOCK_RESET			0x5e
75 #define TF103C_DOCK_SMI_WATCHDOG_RESET			0x5f
76 #define TF103C_DOCK_SMI_ADAPTER_CHANGE			0x60
77 #define TF103C_DOCK_SMI_DOCK_INSERT			0x61
78 #define TF103C_DOCK_SMI_DOCK_REMOVE			0x62
79 #define TF103C_DOCK_SMI_PAD_BL_CHANGE			0x63
80 #define TF103C_DOCK_SMI_HID_STATUS_CHANGED		0x64
81 #define TF103C_DOCK_SMI_HID_WAKEUP			0x65
82 #define TF103C_DOCK_SMI_S3				0x83
83 #define TF103C_DOCK_SMI_S5				0x85
84 #define TF103C_DOCK_SMI_NOTIFY_SHUTDOWN			0x90
85 #define TF103C_DOCK_SMI_RESUME				0x91
86 
87 /*** EC (dockram) I2C device defines ***/
88 #define TF103C_DOCK_EC_ADDR				0x1b
89 
90 #define TF103C_DOCK_EC_CMD_REG				0x0a
91 #define TF103C_DOCK_EC_CMD_LEN				9
92 
93 enum {
94 	TF103C_DOCK_FLAG_HID_OPEN,
95 };
96 
97 struct tf103c_dock_data {
98 	struct delayed_work hpd_work;
99 	struct irq_chip tp_irqchip;
100 	struct irq_domain *tp_irq_domain;
101 	struct i2c_client *ec_client;
102 	struct i2c_client *intr_client;
103 	struct i2c_client *kbd_client;
104 	struct i2c_client *tp_client;
105 	struct gpio_desc *pwr_en;
106 	struct gpio_desc *irq_gpio;
107 	struct gpio_desc *hpd_gpio;
108 	struct input_dev *input;
109 	struct hid_device *hid;
110 	unsigned long flags;
111 	int board_rev;
112 	int irq;
113 	int hpd_irq;
114 	int tp_irq;
115 	int last_press_0x13;
116 	int last_press_0x14;
117 	bool enabled;
118 	bool tp_enabled;
119 	bool altgr_pressed;
120 	bool esc_pressed;
121 	bool filter_esc;
122 	u8 kbd_buf[TF103C_DOCK_KBD_DATA_MAX_LENGTH];
123 };
124 
125 static struct gpiod_lookup_table tf103c_dock_gpios = {
126 	.dev_id = "i2c-" TF103C_DOCK_DEV_NAME,
127 	.table = {
128 		GPIO_LOOKUP("INT33FC:00",      55, "dock_pwr_en", GPIO_ACTIVE_HIGH),
129 		GPIO_LOOKUP("INT33FC:02",       1, "dock_irq", GPIO_ACTIVE_HIGH),
130 		GPIO_LOOKUP("INT33FC:02",      29, "dock_hpd", GPIO_ACTIVE_HIGH),
131 		GPIO_LOOKUP("gpio_crystalcove", 2, "board_rev", GPIO_ACTIVE_HIGH),
132 		{}
133 	},
134 };
135 
136 /* Byte 0 is the length of the rest of the packet */
137 static const u8 tf103c_dock_enable_cmd[9] = { 8, 0x20, 0, 0, 0, 0, 0x20, 0, 0 };
138 static const u8 tf103c_dock_usb_enable_cmd[9] = { 8, 0, 0, 0, 0, 0, 0, 0x40, 0 };
139 static const u8 tf103c_dock_suspend_cmd[9] = { 8, 0, 0x20, 0, 0, 0x22, 0, 0, 0 };
140 
141 /*** keyboard related code ***/
142 
143 static u8 tf103c_dock_kbd_hid_desc[] = {
144 	0x05, 0x01,         /*  Usage Page (Desktop),               */
145 	0x09, 0x06,         /*  Usage (Keyboard),                   */
146 	0xA1, 0x01,         /*  Collection (Application),           */
147 	0x85, 0x11,         /*      Report ID (17),                 */
148 	0x95, 0x08,         /*      Report Count (8),               */
149 	0x75, 0x01,         /*      Report Size (1),                */
150 	0x15, 0x00,         /*      Logical Minimum (0),            */
151 	0x25, 0x01,         /*      Logical Maximum (1),            */
152 	0x05, 0x07,         /*      Usage Page (Keyboard),          */
153 	0x19, 0xE0,         /*      Usage Minimum (KB Leftcontrol), */
154 	0x29, 0xE7,         /*      Usage Maximum (KB Right GUI),   */
155 	0x81, 0x02,         /*      Input (Variable),               */
156 	0x95, 0x01,         /*      Report Count (1),               */
157 	0x75, 0x08,         /*      Report Size (8),                */
158 	0x81, 0x01,         /*      Input (Constant),               */
159 	0x95, 0x06,         /*      Report Count (6),               */
160 	0x75, 0x08,         /*      Report Size (8),                */
161 	0x15, 0x00,         /*      Logical Minimum (0),            */
162 	0x26, 0xFF, 0x00,   /*      Logical Maximum (255),          */
163 	0x05, 0x07,         /*      Usage Page (Keyboard),          */
164 	0x19, 0x00,         /*      Usage Minimum (None),           */
165 	0x2A, 0xFF, 0x00,   /*      Usage Maximum (FFh),            */
166 	0x81, 0x00,         /*      Input,                          */
167 	0xC0                /*  End Collection                      */
168 };
169 
170 static int tf103c_dock_kbd_read(struct tf103c_dock_data *dock)
171 {
172 	struct i2c_client *client = dock->kbd_client;
173 	struct device *dev = &dock->ec_client->dev;
174 	struct i2c_msg msgs[2];
175 	u8 reg[2];
176 	int ret;
177 
178 	reg[0] = TF103C_DOCK_KBD_DATA_REG & 0xff;
179 	reg[1] = TF103C_DOCK_KBD_DATA_REG >> 8;
180 
181 	msgs[0].addr = client->addr;
182 	msgs[0].flags = 0;
183 	msgs[0].len = sizeof(reg);
184 	msgs[0].buf = reg;
185 
186 	msgs[1].addr = client->addr;
187 	msgs[1].flags = I2C_M_RD;
188 	msgs[1].len = TF103C_DOCK_KBD_DATA_MAX_LENGTH;
189 	msgs[1].buf = dock->kbd_buf;
190 
191 	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
192 	if (ret != ARRAY_SIZE(msgs)) {
193 		dev_err(dev, "error %d reading kbd data\n", ret);
194 		return -EIO;
195 	}
196 
197 	return 0;
198 }
199 
200 static void tf103c_dock_kbd_write(struct tf103c_dock_data *dock, u16 cmd)
201 {
202 	struct device *dev = &dock->ec_client->dev;
203 	u8 buf[4];
204 	int ret;
205 
206 	put_unaligned_le16(TF103C_DOCK_KBD_CMD_REG, &buf[0]);
207 	put_unaligned_le16(cmd, &buf[2]);
208 
209 	ret = i2c_master_send(dock->kbd_client, buf, sizeof(buf));
210 	if (ret != sizeof(buf))
211 		dev_err(dev, "error %d writing kbd cmd\n", ret);
212 }
213 
214 /* HID ll_driver functions for forwarding input-reports from the kbd_client */
215 static int tf103c_dock_hid_parse(struct hid_device *hid)
216 {
217 	return hid_parse_report(hid, tf103c_dock_kbd_hid_desc,
218 				sizeof(tf103c_dock_kbd_hid_desc));
219 }
220 
221 static int tf103c_dock_hid_start(struct hid_device *hid)
222 {
223 	return 0;
224 }
225 
226 static void tf103c_dock_hid_stop(struct hid_device *hid)
227 {
228 	hid->claimed = 0;
229 }
230 
231 static int tf103c_dock_hid_open(struct hid_device *hid)
232 {
233 	struct tf103c_dock_data *dock = hid->driver_data;
234 
235 	set_bit(TF103C_DOCK_FLAG_HID_OPEN, &dock->flags);
236 	return 0;
237 }
238 
239 static void tf103c_dock_hid_close(struct hid_device *hid)
240 {
241 	struct tf103c_dock_data *dock = hid->driver_data;
242 
243 	clear_bit(TF103C_DOCK_FLAG_HID_OPEN, &dock->flags);
244 }
245 
246 /* Mandatory, but not used */
247 static int tf103c_dock_hid_raw_request(struct hid_device *hid, u8 reportnum,
248 				       u8 *buf, size_t len, u8 rtype, int reqtype)
249 {
250 	return 0;
251 }
252 
253 static struct hid_ll_driver tf103c_dock_hid_ll_driver = {
254 	.parse = tf103c_dock_hid_parse,
255 	.start = tf103c_dock_hid_start,
256 	.stop = tf103c_dock_hid_stop,
257 	.open = tf103c_dock_hid_open,
258 	.close = tf103c_dock_hid_close,
259 	.raw_request = tf103c_dock_hid_raw_request,
260 };
261 
262 static int tf103c_dock_toprow_codes[13][2] = {
263 	/* Normal,            AltGr pressed */
264 	{ KEY_POWER,          KEY_F1 },
265 	{ KEY_RFKILL,         KEY_F2 },
266 	{ KEY_F21,            KEY_F3 }, /* Touchpad toggle, userspace expects F21 */
267 	{ KEY_BRIGHTNESSDOWN, KEY_F4 },
268 	{ KEY_BRIGHTNESSUP,   KEY_F5 },
269 	{ KEY_CAMERA,         KEY_F6 },
270 	{ KEY_CONFIG,         KEY_F7 },
271 	{ KEY_PREVIOUSSONG,   KEY_F8 },
272 	{ KEY_PLAYPAUSE,      KEY_F9 },
273 	{ KEY_NEXTSONG,       KEY_F10 },
274 	{ KEY_MUTE,           KEY_F11 },
275 	{ KEY_VOLUMEDOWN,     KEY_F12 },
276 	{ KEY_VOLUMEUP,       KEY_SYSRQ },
277 };
278 
279 static void tf103c_dock_report_toprow_kbd_hook(struct tf103c_dock_data *dock)
280 {
281 	u8 *esc, *buf = dock->kbd_buf;
282 	int size;
283 
284 	/*
285 	 * Stop AltGr reports from getting reported on the "Asus TF103C Dock
286 	 * Keyboard" input_dev, since this gets used as "Fn" key for the toprow
287 	 * keys. Instead we report this on the "Asus TF103C Dock Top Row Keys"
288 	 * input_dev, when not used to modify the toprow keys.
289 	 */
290 	dock->altgr_pressed = buf[TF103C_DOCK_KBD_DATA_MODIFIERS] & 0x40;
291 	buf[TF103C_DOCK_KBD_DATA_MODIFIERS] &= ~0x40;
292 
293 	input_report_key(dock->input, KEY_RIGHTALT, dock->altgr_pressed);
294 	input_sync(dock->input);
295 
296 	/* Toggle fnlock on AltGr + Esc press */
297 	buf = buf + TF103C_DOCK_KBD_DATA_KEYS;
298 	size = TF103C_DOCK_KBD_DATA_MAX_LENGTH - TF103C_DOCK_KBD_DATA_KEYS;
299 	esc = memchr(buf, 0x29, size);
300 	if (!dock->esc_pressed && esc) {
301 		if (dock->altgr_pressed) {
302 			fnlock = !fnlock;
303 			dock->filter_esc = true;
304 		}
305 	}
306 	if (esc && dock->filter_esc)
307 		*esc = 0;
308 	else
309 		dock->filter_esc = false;
310 
311 	dock->esc_pressed = esc != NULL;
312 }
313 
314 static void tf103c_dock_toprow_press(struct tf103c_dock_data *dock, int key_code)
315 {
316 	/*
317 	 * Release AltGr before reporting the toprow key, so that userspace
318 	 * sees e.g. just KEY_SUSPEND and not AltGr + KEY_SUSPEND.
319 	 */
320 	if (dock->altgr_pressed) {
321 		input_report_key(dock->input, KEY_RIGHTALT, false);
322 		input_sync(dock->input);
323 	}
324 
325 	input_report_key(dock->input, key_code, true);
326 	input_sync(dock->input);
327 }
328 
329 static void tf103c_dock_toprow_release(struct tf103c_dock_data *dock, int key_code)
330 {
331 	input_report_key(dock->input, key_code, false);
332 	input_sync(dock->input);
333 
334 	if (dock->altgr_pressed) {
335 		input_report_key(dock->input, KEY_RIGHTALT, true);
336 		input_sync(dock->input);
337 	}
338 }
339 
340 static void tf103c_dock_toprow_event(struct tf103c_dock_data *dock,
341 					    int toprow_index, int *last_press)
342 {
343 	int key_code, fn = dock->altgr_pressed ^ fnlock;
344 
345 	if (last_press && *last_press) {
346 		tf103c_dock_toprow_release(dock, *last_press);
347 		*last_press = 0;
348 	}
349 
350 	if (toprow_index < 0)
351 		return;
352 
353 	key_code = tf103c_dock_toprow_codes[toprow_index][fn];
354 	tf103c_dock_toprow_press(dock, key_code);
355 
356 	if (last_press)
357 		*last_press = key_code;
358 	else
359 		tf103c_dock_toprow_release(dock, key_code);
360 }
361 
362 /*
363  * The keyboard sends what appears to be standard I2C-HID input-reports,
364  * except that a 16 bit register address of where the I2C-HID format
365  * input-reports are stored must be send before reading it in a single
366  * (I2C repeated-start) I2C transaction.
367  *
368  * Its unknown how to get the HID descriptors but they are easy to reconstruct:
369  *
370  * Input report id 0x11 is 8 bytes long and contain standard USB HID intf-class,
371  * Boot Interface Subclass reports.
372  * Input report id 0x13 is 2 bytes long and sends Consumer Control events
373  * Input report id 0x14 is 1 byte long and sends System Control events
374  *
375  * However the top row keys (where a normal keyboard has F1-F12 + Print-Screen)
376  * are a mess, using a mix of the 0x13 and 0x14 input reports as well as EC SCI
377  * events; and these need special handling to allow actually sending F1-F12,
378  * since the Fn key on the keyboard only works on the cursor keys and the top
379  * row keys always send their special "Multimedia hotkey" codes.
380  *
381  * So only forward the 0x11 reports to HID and handle the top-row keys here.
382  */
383 static void tf103c_dock_kbd_interrupt(struct tf103c_dock_data *dock)
384 {
385 	struct device *dev = &dock->ec_client->dev;
386 	u8 *buf = dock->kbd_buf;
387 	int size;
388 
389 	if (tf103c_dock_kbd_read(dock))
390 		return;
391 
392 	size = buf[0] | buf[1] << 8;
393 	if (size < TF103C_DOCK_KBD_DATA_MIN_LENGTH ||
394 	    size > TF103C_DOCK_KBD_DATA_MAX_LENGTH) {
395 		dev_err(dev, "error reported kbd pkt size %d is out of range %d-%d\n", size,
396 			TF103C_DOCK_KBD_DATA_MIN_LENGTH,
397 			TF103C_DOCK_KBD_DATA_MAX_LENGTH);
398 		return;
399 	}
400 
401 	switch (buf[2]) {
402 	case 0x11:
403 		if (size != 11)
404 			break;
405 
406 		tf103c_dock_report_toprow_kbd_hook(dock);
407 
408 		if (test_bit(TF103C_DOCK_FLAG_HID_OPEN, &dock->flags))
409 			hid_input_report(dock->hid, HID_INPUT_REPORT, buf + 2, size - 2, 1);
410 		return;
411 	case 0x13:
412 		if (size != 5)
413 			break;
414 
415 		switch (buf[3] | buf[4] << 8) {
416 		case 0:
417 			tf103c_dock_toprow_event(dock, -1, &dock->last_press_0x13);
418 			return;
419 		case 0x70:
420 			tf103c_dock_toprow_event(dock, 3, &dock->last_press_0x13);
421 			return;
422 		case 0x6f:
423 			tf103c_dock_toprow_event(dock, 4, &dock->last_press_0x13);
424 			return;
425 		case 0xb6:
426 			tf103c_dock_toprow_event(dock, 7, &dock->last_press_0x13);
427 			return;
428 		case 0xcd:
429 			tf103c_dock_toprow_event(dock, 8, &dock->last_press_0x13);
430 			return;
431 		case 0xb5:
432 			tf103c_dock_toprow_event(dock, 9, &dock->last_press_0x13);
433 			return;
434 		case 0xe2:
435 			tf103c_dock_toprow_event(dock, 10, &dock->last_press_0x13);
436 			return;
437 		case 0xea:
438 			tf103c_dock_toprow_event(dock, 11, &dock->last_press_0x13);
439 			return;
440 		case 0xe9:
441 			tf103c_dock_toprow_event(dock, 12, &dock->last_press_0x13);
442 			return;
443 		}
444 		break;
445 	case 0x14:
446 		if (size != 4)
447 			break;
448 
449 		switch (buf[3]) {
450 		case 0:
451 			tf103c_dock_toprow_event(dock, -1, &dock->last_press_0x14);
452 			return;
453 		case 1:
454 			tf103c_dock_toprow_event(dock, 0, &dock->last_press_0x14);
455 			return;
456 		}
457 		break;
458 	}
459 
460 	dev_warn(dev, "warning unknown kbd data: %*ph\n", size, buf);
461 }
462 
463 /*** touchpad related code ***/
464 
465 static const struct property_entry tf103c_dock_touchpad_props[] = {
466 	PROPERTY_ENTRY_BOOL("elan,clickpad"),
467 	{ }
468 };
469 
470 static const struct software_node tf103c_dock_touchpad_sw_node = {
471 	.properties = tf103c_dock_touchpad_props,
472 };
473 
474 /*
475  * tf103c_enable_touchpad() is only called from the threaded interrupt handler
476  * and tf103c_disable_touchpad() is only called after the irq is disabled,
477  * so no locking is necessary.
478  */
479 static void tf103c_dock_enable_touchpad(struct tf103c_dock_data *dock)
480 {
481 	struct i2c_board_info board_info = { };
482 	struct device *dev = &dock->ec_client->dev;
483 	int ret;
484 
485 	if (dock->tp_enabled) {
486 		/* Happens after resume, the tp needs to be reinitialized */
487 		ret = device_reprobe(&dock->tp_client->dev);
488 		if (ret)
489 			dev_err_probe(dev, ret, "reprobing tp-client\n");
490 		return;
491 	}
492 
493 	strscpy(board_info.type, "elan_i2c", I2C_NAME_SIZE);
494 	board_info.addr = TF103C_DOCK_TP_ADDR;
495 	board_info.dev_name = TF103C_DOCK_DEV_NAME "-tp";
496 	board_info.irq = dock->tp_irq;
497 	board_info.swnode = &tf103c_dock_touchpad_sw_node;
498 
499 	dock->tp_client = i2c_new_client_device(dock->ec_client->adapter, &board_info);
500 	if (IS_ERR(dock->tp_client)) {
501 		dev_err(dev, "error %ld creating tp client\n", PTR_ERR(dock->tp_client));
502 		return;
503 	}
504 
505 	dock->tp_enabled = true;
506 }
507 
508 static void tf103c_dock_disable_touchpad(struct tf103c_dock_data *dock)
509 {
510 	if (!dock->tp_enabled)
511 		return;
512 
513 	i2c_unregister_device(dock->tp_client);
514 
515 	dock->tp_enabled = false;
516 }
517 
518 /*** interrupt handling code ***/
519 static void tf103c_dock_ec_cmd(struct tf103c_dock_data *dock, const u8 *cmd)
520 {
521 	struct device *dev = &dock->ec_client->dev;
522 	int ret;
523 
524 	ret = i2c_smbus_write_i2c_block_data(dock->ec_client, TF103C_DOCK_EC_CMD_REG,
525 					     TF103C_DOCK_EC_CMD_LEN, cmd);
526 	if (ret)
527 		dev_err(dev, "error %d sending %*ph cmd\n", ret,
528 			TF103C_DOCK_EC_CMD_LEN, cmd);
529 }
530 
531 static void tf103c_dock_sci(struct tf103c_dock_data *dock, u8 val)
532 {
533 	struct device *dev = &dock->ec_client->dev;
534 
535 	switch (val) {
536 	case 2:
537 		tf103c_dock_toprow_event(dock, 1, NULL);
538 		return;
539 	case 4:
540 		tf103c_dock_toprow_event(dock, 2, NULL);
541 		return;
542 	case 8:
543 		tf103c_dock_toprow_event(dock, 5, NULL);
544 		return;
545 	case 17:
546 		tf103c_dock_toprow_event(dock, 6, NULL);
547 		return;
548 	}
549 
550 	dev_warn(dev, "warning unknown SCI value: 0x%02x\n", val);
551 }
552 
553 static void tf103c_dock_smi(struct tf103c_dock_data *dock, u8 val)
554 {
555 	struct device *dev = &dock->ec_client->dev;
556 
557 	switch (val) {
558 	case TF103C_DOCK_SMI_EC_WAKEUP:
559 		tf103c_dock_ec_cmd(dock, tf103c_dock_enable_cmd);
560 		tf103c_dock_ec_cmd(dock, tf103c_dock_usb_enable_cmd);
561 		tf103c_dock_kbd_write(dock, TF103C_DOCK_KBD_CMD_ENABLE);
562 		break;
563 	case TF103C_DOCK_SMI_PAD_BL_CHANGE:
564 		/* There is no backlight, but the EC still sends this */
565 		break;
566 	case TF103C_DOCK_SMI_HID_STATUS_CHANGED:
567 		tf103c_dock_enable_touchpad(dock);
568 		break;
569 	default:
570 		dev_warn(dev, "warning unknown SMI value: 0x%02x\n", val);
571 		break;
572 	}
573 }
574 
575 static irqreturn_t tf103c_dock_irq(int irq, void *data)
576 {
577 	struct tf103c_dock_data *dock = data;
578 	struct device *dev = &dock->ec_client->dev;
579 	u8 intr_data[8];
580 	int ret;
581 
582 	ret = i2c_smbus_read_i2c_block_data(dock->intr_client, TF103C_DOCK_INTR_DATA_REG,
583 					    sizeof(intr_data), intr_data);
584 	if (ret != sizeof(intr_data)) {
585 		dev_err(dev, "error %d reading intr data\n", ret);
586 		return IRQ_NONE;
587 	}
588 
589 	if (!(intr_data[1] & TF103C_DOCK_INTR_DATA1_OBF_MASK))
590 		return IRQ_NONE;
591 
592 	/* intr_data[0] is the length of the rest of the packet */
593 	if (intr_data[0] == 3 && intr_data[1] == TF103C_DOCK_INTR_DATA1_OOB_VALUE &&
594 				 intr_data[2] == TF103C_DOCK_INTR_DATA2_OOB_VALUE) {
595 		/* intr_data[3] seems to contain a HID input report id */
596 		switch (intr_data[3]) {
597 		case 0x01:
598 			handle_nested_irq(dock->tp_irq);
599 			break;
600 		case 0x11:
601 		case 0x13:
602 		case 0x14:
603 			tf103c_dock_kbd_interrupt(dock);
604 			break;
605 		default:
606 			dev_warn(dev, "warning unknown intr_data[3]: 0x%02x\n", intr_data[3]);
607 			break;
608 		}
609 		return IRQ_HANDLED;
610 	}
611 
612 	if (intr_data[1] & TF103C_DOCK_INTR_DATA1_SCI_MASK) {
613 		tf103c_dock_sci(dock, intr_data[2]);
614 		return IRQ_HANDLED;
615 	}
616 
617 	if (intr_data[1] & TF103C_DOCK_INTR_DATA1_SMI_MASK) {
618 		tf103c_dock_smi(dock, intr_data[2]);
619 		return IRQ_HANDLED;
620 	}
621 
622 	dev_warn(dev, "warning unknown intr data: %*ph\n", 8, intr_data);
623 	return IRQ_NONE;
624 }
625 
626 /*
627  * tf103c_dock_[dis|en]able only run from hpd_work or at times when
628  * hpd_work cannot run (hpd_irq disabled), so no locking is necessary.
629  */
630 static void tf103c_dock_enable(struct tf103c_dock_data *dock)
631 {
632 	if (dock->enabled)
633 		return;
634 
635 	if (dock->board_rev != 2)
636 		gpiod_set_value(dock->pwr_en, 1);
637 
638 	msleep(500);
639 	enable_irq(dock->irq);
640 
641 	dock->enabled = true;
642 }
643 
644 static void tf103c_dock_disable(struct tf103c_dock_data *dock)
645 {
646 	if (!dock->enabled)
647 		return;
648 
649 	disable_irq(dock->irq);
650 	tf103c_dock_disable_touchpad(dock);
651 	if (dock->board_rev != 2)
652 		gpiod_set_value(dock->pwr_en, 0);
653 
654 	dock->enabled = false;
655 }
656 
657 static void tf103c_dock_hpd_work(struct work_struct *work)
658 {
659 	struct tf103c_dock_data *dock =
660 		container_of(work, struct tf103c_dock_data, hpd_work.work);
661 
662 	if (gpiod_get_value(dock->hpd_gpio))
663 		tf103c_dock_enable(dock);
664 	else
665 		tf103c_dock_disable(dock);
666 }
667 
668 static irqreturn_t tf103c_dock_hpd_irq(int irq, void *data)
669 {
670 	struct tf103c_dock_data *dock = data;
671 
672 	mod_delayed_work(system_long_wq, &dock->hpd_work, TF103C_DOCK_HPD_DEBOUNCE);
673 	return IRQ_HANDLED;
674 }
675 
676 static void tf103c_dock_start_hpd(struct tf103c_dock_data *dock)
677 {
678 	enable_irq(dock->hpd_irq);
679 	/* Sync current HPD status */
680 	queue_delayed_work(system_long_wq, &dock->hpd_work, TF103C_DOCK_HPD_DEBOUNCE);
681 }
682 
683 static void tf103c_dock_stop_hpd(struct tf103c_dock_data *dock)
684 {
685 	disable_irq(dock->hpd_irq);
686 	cancel_delayed_work_sync(&dock->hpd_work);
687 }
688 
689 /*** probe ***/
690 
691 static const struct dmi_system_id tf103c_dock_dmi_ids[] = {
692 	{
693 		.matches = {
694 			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
695 			DMI_MATCH(DMI_PRODUCT_NAME, "TF103C"),
696 		},
697 	},
698 	{ }
699 };
700 
701 static void tf103c_dock_non_devm_cleanup(void *data)
702 {
703 	struct tf103c_dock_data *dock = data;
704 
705 	if (dock->tp_irq_domain)
706 		irq_domain_remove(dock->tp_irq_domain);
707 
708 	if (!IS_ERR_OR_NULL(dock->hid))
709 		hid_destroy_device(dock->hid);
710 
711 	i2c_unregister_device(dock->kbd_client);
712 	i2c_unregister_device(dock->intr_client);
713 	gpiod_remove_lookup_table(&tf103c_dock_gpios);
714 }
715 
716 static int tf103c_dock_probe(struct i2c_client *client)
717 {
718 	struct i2c_board_info board_info = { };
719 	struct device *dev = &client->dev;
720 	struct gpio_desc *board_rev_gpio;
721 	struct tf103c_dock_data *dock;
722 	enum gpiod_flags flags;
723 	int i, ret;
724 
725 	/* GPIOs are hardcoded for the Asus TF103C, don't bind on other devs */
726 	if (!dmi_check_system(tf103c_dock_dmi_ids))
727 		return -ENODEV;
728 
729 	dock = devm_kzalloc(dev, sizeof(*dock), GFP_KERNEL);
730 	if (!dock)
731 		return -ENOMEM;
732 
733 	INIT_DELAYED_WORK(&dock->hpd_work, tf103c_dock_hpd_work);
734 
735 	/* 1. Get GPIOs and their IRQs */
736 	gpiod_add_lookup_table(&tf103c_dock_gpios);
737 
738 	ret = devm_add_action_or_reset(dev, tf103c_dock_non_devm_cleanup, dock);
739 	if (ret)
740 		return ret;
741 
742 	/*
743 	 * The pin is configured as input by default, use ASIS because otherwise
744 	 * the gpio-crystalcove.c switches off the internal pull-down replacing
745 	 * it with a pull-up.
746 	 */
747 	board_rev_gpio = gpiod_get(dev, "board_rev", GPIOD_ASIS);
748 	if (IS_ERR(board_rev_gpio))
749 		return dev_err_probe(dev, PTR_ERR(board_rev_gpio), "requesting board_rev GPIO\n");
750 	dock->board_rev = gpiod_get_value_cansleep(board_rev_gpio) + 1;
751 	gpiod_put(board_rev_gpio);
752 
753 	/*
754 	 * The Android driver drives the dock-pwr-en pin high at probe for
755 	 * revision 2 boards and then never touches it again?
756 	 * This code has only been tested on a revision 1 board, so for now
757 	 * just mimick what Android does on revision 2 boards.
758 	 */
759 	flags = (dock->board_rev == 2) ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
760 	dock->pwr_en = devm_gpiod_get(dev, "dock_pwr_en", flags);
761 	if (IS_ERR(dock->pwr_en))
762 		return dev_err_probe(dev, PTR_ERR(dock->pwr_en), "requesting pwr_en GPIO\n");
763 
764 	dock->irq_gpio = devm_gpiod_get(dev, "dock_irq", GPIOD_IN);
765 	if (IS_ERR(dock->irq_gpio))
766 		return dev_err_probe(dev, PTR_ERR(dock->irq_gpio), "requesting IRQ GPIO\n");
767 
768 	dock->irq = gpiod_to_irq(dock->irq_gpio);
769 	if (dock->irq < 0)
770 		return dev_err_probe(dev, dock->irq, "getting dock IRQ");
771 
772 	ret = devm_request_threaded_irq(dev, dock->irq, NULL, tf103c_dock_irq,
773 					IRQF_TRIGGER_LOW | IRQF_ONESHOT | IRQF_NO_AUTOEN,
774 					"dock_irq", dock);
775 	if (ret)
776 		return dev_err_probe(dev, ret, "requesting dock IRQ");
777 
778 	dock->hpd_gpio = devm_gpiod_get(dev, "dock_hpd", GPIOD_IN);
779 	if (IS_ERR(dock->hpd_gpio))
780 		return dev_err_probe(dev, PTR_ERR(dock->hpd_gpio), "requesting HPD GPIO\n");
781 
782 	dock->hpd_irq = gpiod_to_irq(dock->hpd_gpio);
783 	if (dock->hpd_irq < 0)
784 		return dev_err_probe(dev, dock->hpd_irq, "getting HPD IRQ");
785 
786 	ret = devm_request_irq(dev, dock->hpd_irq, tf103c_dock_hpd_irq,
787 			       IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_NO_AUTOEN,
788 			       "dock_hpd", dock);
789 	if (ret)
790 		return ret;
791 
792 	/*
793 	 * 2. Create I2C clients. The dock uses 4 different i2c addresses,
794 	 * the ACPI NPCE69A node being probed points to the EC address.
795 	 */
796 	dock->ec_client = client;
797 
798 	strscpy(board_info.type, "tf103c-dock-intr", I2C_NAME_SIZE);
799 	board_info.addr = TF103C_DOCK_INTR_ADDR;
800 	board_info.dev_name = TF103C_DOCK_DEV_NAME "-intr";
801 
802 	dock->intr_client = i2c_new_client_device(client->adapter, &board_info);
803 	if (IS_ERR(dock->intr_client))
804 		return dev_err_probe(dev, PTR_ERR(dock->intr_client), "creating intr client\n");
805 
806 	strscpy(board_info.type, "tf103c-dock-kbd", I2C_NAME_SIZE);
807 	board_info.addr = TF103C_DOCK_KBD_ADDR;
808 	board_info.dev_name = TF103C_DOCK_DEV_NAME "-kbd";
809 
810 	dock->kbd_client = i2c_new_client_device(client->adapter, &board_info);
811 	if (IS_ERR(dock->kbd_client))
812 		return dev_err_probe(dev, PTR_ERR(dock->kbd_client), "creating kbd client\n");
813 
814 	/* 3. Create input_dev for the top row of the keyboard */
815 	dock->input = devm_input_allocate_device(dev);
816 	if (!dock->input)
817 		return -ENOMEM;
818 
819 	dock->input->name = "Asus TF103C Dock Top Row Keys";
820 	dock->input->phys = dev_name(dev);
821 	dock->input->dev.parent = dev;
822 	dock->input->id.bustype = BUS_I2C;
823 	dock->input->id.vendor = /* USB_VENDOR_ID_ASUSTEK */
824 	dock->input->id.product = /* From TF-103-C */
825 	dock->input->id.version = 0x0100;  /* 1.0 */
826 
827 	for (i = 0; i < ARRAY_SIZE(tf103c_dock_toprow_codes); i++) {
828 		input_set_capability(dock->input, EV_KEY, tf103c_dock_toprow_codes[i][0]);
829 		input_set_capability(dock->input, EV_KEY, tf103c_dock_toprow_codes[i][1]);
830 	}
831 	input_set_capability(dock->input, EV_KEY, KEY_RIGHTALT);
832 
833 	ret = input_register_device(dock->input);
834 	if (ret)
835 		return ret;
836 
837 	/* 4. Create HID device for the keyboard */
838 	dock->hid = hid_allocate_device();
839 	if (IS_ERR(dock->hid))
840 		return dev_err_probe(dev, PTR_ERR(dock->hid), "allocating hid dev\n");
841 
842 	dock->hid->driver_data = dock;
843 	dock->hid->ll_driver = &tf103c_dock_hid_ll_driver;
844 	dock->hid->dev.parent = &client->dev;
845 	dock->hid->bus = BUS_I2C;
846 	dock->hid->vendor = 0x0b05;  /* USB_VENDOR_ID_ASUSTEK */
847 	dock->hid->product = 0x0103; /* From TF-103-C */
848 	dock->hid->version = 0x0100; /* 1.0 */
849 	strscpy(dock->hid->name, "Asus TF103C Dock Keyboard", sizeof(dock->hid->name));
850 	strscpy(dock->hid->phys, dev_name(dev), sizeof(dock->hid->phys));
851 
852 	ret = hid_add_device(dock->hid);
853 	if (ret)
854 		return dev_err_probe(dev, ret, "adding hid dev\n");
855 
856 	/* 5. Setup irqchip for touchpad IRQ pass-through */
857 	dock->tp_irqchip.name = KBUILD_MODNAME;
858 
859 	dock->tp_irq_domain = irq_domain_add_linear(NULL, 1, &irq_domain_simple_ops, NULL);
860 	if (!dock->tp_irq_domain)
861 		return -ENOMEM;
862 
863 	dock->tp_irq = irq_create_mapping(dock->tp_irq_domain, 0);
864 	if (!dock->tp_irq)
865 		return -ENOMEM;
866 
867 	irq_set_chip_data(dock->tp_irq, dock);
868 	irq_set_chip_and_handler(dock->tp_irq, &dock->tp_irqchip, handle_simple_irq);
869 	irq_set_nested_thread(dock->tp_irq, true);
870 	irq_set_noprobe(dock->tp_irq);
871 
872 	dev_info(dev, "Asus TF103C board-revision: %d\n", dock->board_rev);
873 
874 	tf103c_dock_start_hpd(dock);
875 
876 	device_init_wakeup(dev, true);
877 	i2c_set_clientdata(client, dock);
878 	return 0;
879 }
880 
881 static void tf103c_dock_remove(struct i2c_client *client)
882 {
883 	struct tf103c_dock_data *dock = i2c_get_clientdata(client);
884 
885 	tf103c_dock_stop_hpd(dock);
886 	tf103c_dock_disable(dock);
887 }
888 
889 static int __maybe_unused tf103c_dock_suspend(struct device *dev)
890 {
891 	struct tf103c_dock_data *dock = dev_get_drvdata(dev);
892 
893 	tf103c_dock_stop_hpd(dock);
894 
895 	if (dock->enabled) {
896 		tf103c_dock_ec_cmd(dock, tf103c_dock_suspend_cmd);
897 
898 		if (device_may_wakeup(dev))
899 			enable_irq_wake(dock->irq);
900 	}
901 
902 	return 0;
903 }
904 
905 static int __maybe_unused tf103c_dock_resume(struct device *dev)
906 {
907 	struct tf103c_dock_data *dock = dev_get_drvdata(dev);
908 
909 	if (dock->enabled) {
910 		if (device_may_wakeup(dev))
911 			disable_irq_wake(dock->irq);
912 
913 		/* Don't try to resume if the dock was unplugged during suspend */
914 		if (gpiod_get_value(dock->hpd_gpio))
915 			tf103c_dock_ec_cmd(dock, tf103c_dock_enable_cmd);
916 	}
917 
918 	tf103c_dock_start_hpd(dock);
919 	return 0;
920 }
921 
922 static SIMPLE_DEV_PM_OPS(tf103c_dock_pm_ops, tf103c_dock_suspend, tf103c_dock_resume);
923 
924 static const struct acpi_device_id tf103c_dock_acpi_match[] = {
925 	{"NPCE69A"},
926 	{ }
927 };
928 MODULE_DEVICE_TABLE(acpi, tf103c_dock_acpi_match);
929 
930 static struct i2c_driver tf103c_dock_driver = {
931 	.driver = {
932 		.name = "asus-tf103c-dock",
933 		.pm = &tf103c_dock_pm_ops,
934 		.acpi_match_table = tf103c_dock_acpi_match,
935 	},
936 	.probe_new = tf103c_dock_probe,
937 	.remove	= tf103c_dock_remove,
938 };
939 module_i2c_driver(tf103c_dock_driver);
940 
941 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com");
942 MODULE_DESCRIPTION("X86 Android tablets DSDT fixups driver");
943 MODULE_LICENSE("GPL");
944