1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * HID Driver for ELAN Touchpad
5 * Currently only supports touchpad found on HP Pavilion X2 10
7 * Copyright (c) 2016 Alexandrov Stanislav <neko@nya.ai>
10 #include <linux/hid.h>
11 #include <linux/input/mt.h>
12 #include <linux/leds.h>
13 #include <linux/module.h>
14 #include <linux/usb.h>
18 #define ELAN_MT_I2C 0x5d
19 #define ELAN_SINGLE_FINGER 0x81
20 #define ELAN_MT_FIRST_FINGER 0x82
21 #define ELAN_MT_SECOND_FINGER 0x83
22 #define ELAN_INPUT_REPORT_SIZE 8
23 #define ELAN_I2C_REPORT_SIZE 32
24 #define ELAN_FINGER_DATA_LEN 5
25 #define ELAN_MAX_FINGERS 5
26 #define ELAN_MAX_PRESSURE 255
27 #define ELAN_TP_USB_INTF 1
29 #define ELAN_FEATURE_REPORT 0x0d
30 #define ELAN_FEATURE_SIZE 5
31 #define ELAN_PARAM_MAX_X 6
32 #define ELAN_PARAM_MAX_Y 7
33 #define ELAN_PARAM_RES 8
35 #define ELAN_MUTE_LED_REPORT 0xBC
36 #define ELAN_LED_REPORT_SIZE 8
38 #define ELAN_HAS_LED BIT(0)
41 struct input_dev
*input
;
42 u8 prev_report
[ELAN_INPUT_REPORT_SIZE
];
43 struct led_classdev mute_led
;
51 static int is_not_elan_touchpad(struct hid_device
*hdev
)
53 if (hdev
->bus
== BUS_USB
) {
54 struct usb_interface
*intf
= to_usb_interface(hdev
->dev
.parent
);
56 return (intf
->altsetting
->desc
.bInterfaceNumber
!=
63 static int elan_input_mapping(struct hid_device
*hdev
, struct hid_input
*hi
,
64 struct hid_field
*field
, struct hid_usage
*usage
,
65 unsigned long **bit
, int *max
)
67 if (is_not_elan_touchpad(hdev
))
70 if (field
->report
->id
== ELAN_SINGLE_FINGER
||
71 field
->report
->id
== ELAN_MT_FIRST_FINGER
||
72 field
->report
->id
== ELAN_MT_SECOND_FINGER
||
73 field
->report
->id
== ELAN_MT_I2C
)
79 static int elan_get_device_param(struct hid_device
*hdev
,
80 unsigned char *dmabuf
, unsigned char param
)
84 dmabuf
[0] = ELAN_FEATURE_REPORT
;
90 ret
= hid_hw_raw_request(hdev
, ELAN_FEATURE_REPORT
, dmabuf
,
91 ELAN_FEATURE_SIZE
, HID_FEATURE_REPORT
,
93 if (ret
!= ELAN_FEATURE_SIZE
) {
94 hid_err(hdev
, "Set report error for parm %d: %d\n", param
, ret
);
98 ret
= hid_hw_raw_request(hdev
, ELAN_FEATURE_REPORT
, dmabuf
,
99 ELAN_FEATURE_SIZE
, HID_FEATURE_REPORT
,
101 if (ret
!= ELAN_FEATURE_SIZE
) {
102 hid_err(hdev
, "Get report error for parm %d: %d\n", param
, ret
);
109 static unsigned int elan_convert_res(char val
)
112 * (value from firmware) * 10 + 790 = dpi
113 * dpi * 10 / 254 = dots/mm
115 return (val
* 10 + 790) * 10 / 254;
118 static int elan_get_device_params(struct hid_device
*hdev
)
120 struct elan_drvdata
*drvdata
= hid_get_drvdata(hdev
);
121 unsigned char *dmabuf
;
124 dmabuf
= kmalloc(ELAN_FEATURE_SIZE
, GFP_KERNEL
);
128 ret
= elan_get_device_param(hdev
, dmabuf
, ELAN_PARAM_MAX_X
);
132 drvdata
->max_x
= (dmabuf
[4] << 8) | dmabuf
[3];
134 ret
= elan_get_device_param(hdev
, dmabuf
, ELAN_PARAM_MAX_Y
);
138 drvdata
->max_y
= (dmabuf
[4] << 8) | dmabuf
[3];
140 ret
= elan_get_device_param(hdev
, dmabuf
, ELAN_PARAM_RES
);
144 drvdata
->res_x
= elan_convert_res(dmabuf
[3]);
145 drvdata
->res_y
= elan_convert_res(dmabuf
[4]);
152 static int elan_input_configured(struct hid_device
*hdev
, struct hid_input
*hi
)
155 struct input_dev
*input
;
156 struct elan_drvdata
*drvdata
= hid_get_drvdata(hdev
);
158 if (is_not_elan_touchpad(hdev
))
161 ret
= elan_get_device_params(hdev
);
165 input
= devm_input_allocate_device(&hdev
->dev
);
169 input
->name
= "Elan Touchpad";
170 input
->phys
= hdev
->phys
;
171 input
->uniq
= hdev
->uniq
;
172 input
->id
.bustype
= hdev
->bus
;
173 input
->id
.vendor
= hdev
->vendor
;
174 input
->id
.product
= hdev
->product
;
175 input
->id
.version
= hdev
->version
;
176 input
->dev
.parent
= &hdev
->dev
;
178 input_set_abs_params(input
, ABS_MT_POSITION_X
, 0, drvdata
->max_x
,
180 input_set_abs_params(input
, ABS_MT_POSITION_Y
, 0, drvdata
->max_y
,
182 input_set_abs_params(input
, ABS_MT_PRESSURE
, 0, ELAN_MAX_PRESSURE
,
185 __set_bit(BTN_LEFT
, input
->keybit
);
186 __set_bit(INPUT_PROP_BUTTONPAD
, input
->propbit
);
188 ret
= input_mt_init_slots(input
, ELAN_MAX_FINGERS
, INPUT_MT_POINTER
);
190 hid_err(hdev
, "Failed to init elan MT slots: %d\n", ret
);
194 input_abs_set_res(input
, ABS_X
, drvdata
->res_x
);
195 input_abs_set_res(input
, ABS_Y
, drvdata
->res_y
);
197 ret
= input_register_device(input
);
199 hid_err(hdev
, "Failed to register elan input device: %d\n",
201 input_free_device(input
);
205 drvdata
->input
= input
;
210 static void elan_report_mt_slot(struct elan_drvdata
*drvdata
, u8
*data
,
211 unsigned int slot_num
)
213 struct input_dev
*input
= drvdata
->input
;
216 bool active
= !!data
;
218 input_mt_slot(input
, slot_num
);
219 input_mt_report_slot_state(input
, MT_TOOL_FINGER
, active
);
221 x
= ((data
[0] & 0xF0) << 4) | data
[1];
223 (((data
[0] & 0x07) << 8) | data
[2]);
226 input_report_abs(input
, ABS_MT_POSITION_X
, x
);
227 input_report_abs(input
, ABS_MT_POSITION_Y
, y
);
228 input_report_abs(input
, ABS_MT_PRESSURE
, p
);
232 static void elan_usb_report_input(struct elan_drvdata
*drvdata
, u8
*data
)
235 struct input_dev
*input
= drvdata
->input
;
238 * There is 3 types of reports: for single touch,
239 * for multitouch - first finger and for multitouch - second finger
241 * packet structure for ELAN_SINGLE_FINGER and ELAN_MT_FIRST_FINGER:
243 * byte 1: 1 0 0 0 0 0 0 1 // 0x81 or 0x82
244 * byte 2: 0 0 0 0 0 0 0 0 // looks like unused
245 * byte 3: f5 f4 f3 f2 f1 0 0 L
246 * byte 4: x12 x11 x10 x9 0? y11 y10 y9
247 * byte 5: x8 x7 x6 x5 x4 x3 x2 x1
248 * byte 6: y8 y7 y6 y5 y4 y3 y2 y1
249 * byte 7: sy4 sy3 sy2 sy1 sx4 sx3 sx2 sx1
250 * byte 8: p8 p7 p6 p5 p4 p3 p2 p1
252 * packet structure for ELAN_MT_SECOND_FINGER:
254 * byte 1: 1 0 0 0 0 0 1 1 // 0x83
255 * byte 2: x12 x11 x10 x9 0 y11 y10 y9
256 * byte 3: x8 x7 x6 x5 x4 x3 x2 x1
257 * byte 4: y8 y7 y6 y5 y4 y3 y2 y1
258 * byte 5: sy4 sy3 sy2 sy1 sx4 sx3 sx2 sx1
259 * byte 6: p8 p7 p6 p5 p4 p3 p2 p1
260 * byte 7: 0 0 0 0 0 0 0 0
261 * byte 8: 0 0 0 0 0 0 0 0
263 * f5-f1: finger touch bits
265 * sy / sx: finger width / height expressed in traces, the total number
266 * of traces can be queried by doing a HID_REQ_SET_REPORT
267 * { 0x0d, 0x05, 0x03, 0x05, 0x01 } followed by a GET, in the
268 * returned buf, buf[3]=no-x-traces, buf[4]=no-y-traces.
272 if (data
[0] == ELAN_SINGLE_FINGER
) {
273 for (i
= 0; i
< ELAN_MAX_FINGERS
; i
++) {
274 if (data
[2] & BIT(i
+ 3))
275 elan_report_mt_slot(drvdata
, data
+ 3, i
);
277 elan_report_mt_slot(drvdata
, NULL
, i
);
279 input_report_key(input
, BTN_LEFT
, data
[2] & 0x01);
282 * When touched with two fingers Elan touchpad will emit two HID reports
283 * first is ELAN_MT_FIRST_FINGER and second is ELAN_MT_SECOND_FINGER
284 * we will save ELAN_MT_FIRST_FINGER report and wait for
285 * ELAN_MT_SECOND_FINGER to finish multitouch
287 if (data
[0] == ELAN_MT_FIRST_FINGER
) {
288 memcpy(drvdata
->prev_report
, data
,
289 sizeof(drvdata
->prev_report
));
293 if (data
[0] == ELAN_MT_SECOND_FINGER
) {
295 u8
*prev_report
= drvdata
->prev_report
;
297 if (prev_report
[0] != ELAN_MT_FIRST_FINGER
)
300 for (i
= 0; i
< ELAN_MAX_FINGERS
; i
++) {
301 if (prev_report
[2] & BIT(i
+ 3)) {
304 elan_report_mt_slot(drvdata
, prev_report
+ 3, i
);
306 elan_report_mt_slot(drvdata
, data
+ 1, i
);
309 elan_report_mt_slot(drvdata
, NULL
, i
);
312 input_report_key(input
, BTN_LEFT
, prev_report
[2] & 0x01);
315 input_mt_sync_frame(input
);
319 static void elan_i2c_report_input(struct elan_drvdata
*drvdata
, u8
*data
)
321 struct input_dev
*input
= drvdata
->input
;
326 * Elan MT touchpads in i2c mode send finger data in the same format
327 * as in USB mode, but then with all fingers in a single packet.
329 * packet structure for ELAN_MT_I2C:
331 * byte 1: 1 0 0 1 1 1 0 1 // 0x5d
332 * byte 2: f5 f4 f3 f2 f1 0 0 L
333 * byte 3: x12 x11 x10 x9 0? y11 y10 y9
334 * byte 4: x8 x7 x6 x5 x4 x3 x2 x1
335 * byte 5: y8 y7 y6 y5 y4 y3 y2 y1
336 * byte 6: sy4 sy3 sy2 sy1 sx4 sx3 sx2 sx1
337 * byte 7: p8 p7 p6 p5 p4 p3 p2 p1
338 * byte 8-12: Same as byte 3-7 for second finger down
339 * byte 13-17: Same as byte 3-7 for third finger down
340 * byte 18-22: Same as byte 3-7 for fourth finger down
341 * byte 23-27: Same as byte 3-7 for fifth finger down
344 finger_data
= data
+ 2;
345 for (i
= 0; i
< ELAN_MAX_FINGERS
; i
++) {
346 if (data
[1] & BIT(i
+ 3)) {
347 elan_report_mt_slot(drvdata
, finger_data
, i
);
348 finger_data
+= ELAN_FINGER_DATA_LEN
;
350 elan_report_mt_slot(drvdata
, NULL
, i
);
354 input_report_key(input
, BTN_LEFT
, data
[1] & 0x01);
355 input_mt_sync_frame(input
);
359 static int elan_raw_event(struct hid_device
*hdev
,
360 struct hid_report
*report
, u8
*data
, int size
)
362 struct elan_drvdata
*drvdata
= hid_get_drvdata(hdev
);
364 if (is_not_elan_touchpad(hdev
))
367 if (data
[0] == ELAN_SINGLE_FINGER
||
368 data
[0] == ELAN_MT_FIRST_FINGER
||
369 data
[0] == ELAN_MT_SECOND_FINGER
) {
370 if (size
== ELAN_INPUT_REPORT_SIZE
) {
371 elan_usb_report_input(drvdata
, data
);
376 if (data
[0] == ELAN_MT_I2C
&& size
== ELAN_I2C_REPORT_SIZE
) {
377 elan_i2c_report_input(drvdata
, data
);
384 static int elan_start_multitouch(struct hid_device
*hdev
)
389 * This byte sequence will enable multitouch mode and disable
392 static const unsigned char buf
[] = { 0x0D, 0x00, 0x03, 0x21, 0x00 };
393 unsigned char *dmabuf
= kmemdup(buf
, sizeof(buf
), GFP_KERNEL
);
398 ret
= hid_hw_raw_request(hdev
, dmabuf
[0], dmabuf
, sizeof(buf
),
399 HID_FEATURE_REPORT
, HID_REQ_SET_REPORT
);
403 if (ret
!= sizeof(buf
)) {
404 hid_err(hdev
, "Failed to start multitouch: %d\n", ret
);
411 static enum led_brightness
elan_mute_led_get_brigtness(struct led_classdev
*led_cdev
)
413 struct device
*dev
= led_cdev
->dev
->parent
;
414 struct hid_device
*hdev
= to_hid_device(dev
);
415 struct elan_drvdata
*drvdata
= hid_get_drvdata(hdev
);
417 return drvdata
->mute_led_state
;
420 static int elan_mute_led_set_brigtness(struct led_classdev
*led_cdev
,
421 enum led_brightness value
)
425 struct device
*dev
= led_cdev
->dev
->parent
;
426 struct hid_device
*hdev
= to_hid_device(dev
);
427 struct elan_drvdata
*drvdata
= hid_get_drvdata(hdev
);
429 unsigned char *dmabuf
= kzalloc(ELAN_LED_REPORT_SIZE
, GFP_KERNEL
);
436 dmabuf
[0] = ELAN_MUTE_LED_REPORT
;
438 dmabuf
[2] = led_state
;
440 ret
= hid_hw_raw_request(hdev
, dmabuf
[0], dmabuf
, ELAN_LED_REPORT_SIZE
,
441 HID_FEATURE_REPORT
, HID_REQ_SET_REPORT
);
445 if (ret
!= ELAN_LED_REPORT_SIZE
) {
446 hid_err(hdev
, "Failed to set mute led brightness: %d\n", ret
);
450 drvdata
->mute_led_state
= led_state
;
454 static int elan_init_mute_led(struct hid_device
*hdev
)
456 struct elan_drvdata
*drvdata
= hid_get_drvdata(hdev
);
457 struct led_classdev
*mute_led
= &drvdata
->mute_led
;
459 mute_led
->name
= "elan:red:mute";
460 mute_led
->brightness_get
= elan_mute_led_get_brigtness
;
461 mute_led
->brightness_set_blocking
= elan_mute_led_set_brigtness
;
462 mute_led
->max_brightness
= LED_ON
;
463 mute_led
->dev
= &hdev
->dev
;
465 return devm_led_classdev_register(&hdev
->dev
, mute_led
);
468 static int elan_probe(struct hid_device
*hdev
, const struct hid_device_id
*id
)
471 struct elan_drvdata
*drvdata
;
473 drvdata
= devm_kzalloc(&hdev
->dev
, sizeof(*drvdata
), GFP_KERNEL
);
478 hid_set_drvdata(hdev
, drvdata
);
480 ret
= hid_parse(hdev
);
482 hid_err(hdev
, "Hid Parse failed\n");
486 ret
= hid_hw_start(hdev
, HID_CONNECT_DEFAULT
);
488 hid_err(hdev
, "Hid hw start failed\n");
492 if (is_not_elan_touchpad(hdev
))
495 if (!drvdata
->input
) {
496 hid_err(hdev
, "Input device is not registered\n");
501 ret
= elan_start_multitouch(hdev
);
505 if (id
->driver_data
& ELAN_HAS_LED
) {
506 ret
= elan_init_mute_led(hdev
);
517 static void elan_remove(struct hid_device
*hdev
)
522 static const struct hid_device_id elan_devices
[] = {
523 { HID_USB_DEVICE(USB_VENDOR_ID_ELAN
, USB_DEVICE_ID_HP_X2
),
524 .driver_data
= ELAN_HAS_LED
},
525 { HID_USB_DEVICE(USB_VENDOR_ID_ELAN
, USB_DEVICE_ID_HP_X2_10_COVER
),
526 .driver_data
= ELAN_HAS_LED
},
527 { HID_I2C_DEVICE(USB_VENDOR_ID_ELAN
, USB_DEVICE_ID_TOSHIBA_CLICK_L9W
) },
530 MODULE_DEVICE_TABLE(hid
, elan_devices
);
532 static struct hid_driver elan_driver
= {
534 .id_table
= elan_devices
,
535 .input_mapping
= elan_input_mapping
,
536 .input_configured
= elan_input_configured
,
537 .raw_event
= elan_raw_event
,
539 .remove
= elan_remove
,
542 module_hid_driver(elan_driver
);
544 MODULE_LICENSE("GPL");
545 MODULE_AUTHOR("Alexandrov Stanislav");
546 MODULE_DESCRIPTION("Driver for HID ELAN Touchpads");