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9#include <linux/kernel.h>
10
11#include <linux/delay.h>
12#include <linux/gpio/consumer.h>
13#include <linux/input.h>
14#include <linux/input/mt.h>
15#include <linux/interrupt.h>
16#include <linux/module.h>
17#include <linux/slab.h>
18#include <linux/spi/spi.h>
19#include <linux/acpi.h>
20
21#include <asm/unaligned.h>
22
23#define SURFACE3_PACKET_SIZE 264
24
25#define SURFACE3_REPORT_TOUCH 0xd2
26#define SURFACE3_REPORT_PEN 0x16
27
28struct surface3_ts_data {
29 struct spi_device *spi;
30 struct gpio_desc *gpiod_rst[2];
31 struct input_dev *input_dev;
32 struct input_dev *pen_input_dev;
33 int pen_tool;
34
35 u8 rd_buf[SURFACE3_PACKET_SIZE] ____cacheline_aligned;
36};
37
38struct surface3_ts_data_finger {
39 u8 status;
40 __le16 tracking_id;
41 __le16 x;
42 __le16 cx;
43 __le16 y;
44 __le16 cy;
45 __le16 width;
46 __le16 height;
47 u32 padding;
48} __packed;
49
50struct surface3_ts_data_pen {
51 u8 status;
52 __le16 x;
53 __le16 y;
54 __le16 pressure;
55 u8 padding;
56} __packed;
57
58static int surface3_spi_read(struct surface3_ts_data *ts_data)
59{
60 struct spi_device *spi = ts_data->spi;
61
62 memset(ts_data->rd_buf, 0, sizeof(ts_data->rd_buf));
63 return spi_read(spi, ts_data->rd_buf, sizeof(ts_data->rd_buf));
64}
65
66static void surface3_spi_report_touch(struct surface3_ts_data *ts_data,
67 struct surface3_ts_data_finger *finger)
68{
69 int st = finger->status & 0x01;
70 int slot;
71
72 slot = input_mt_get_slot_by_key(ts_data->input_dev,
73 get_unaligned_le16(&finger->tracking_id));
74 if (slot < 0)
75 return;
76
77 input_mt_slot(ts_data->input_dev, slot);
78 input_mt_report_slot_state(ts_data->input_dev, MT_TOOL_FINGER, st);
79 if (st) {
80 input_report_abs(ts_data->input_dev,
81 ABS_MT_POSITION_X,
82 get_unaligned_le16(&finger->x));
83 input_report_abs(ts_data->input_dev,
84 ABS_MT_POSITION_Y,
85 get_unaligned_le16(&finger->y));
86 input_report_abs(ts_data->input_dev,
87 ABS_MT_WIDTH_MAJOR,
88 get_unaligned_le16(&finger->width));
89 input_report_abs(ts_data->input_dev,
90 ABS_MT_WIDTH_MINOR,
91 get_unaligned_le16(&finger->height));
92 }
93}
94
95static void surface3_spi_process_touch(struct surface3_ts_data *ts_data, u8 *data)
96{
97 u16 timestamp;
98 unsigned int i;
99 timestamp = get_unaligned_le16(&data[15]);
100
101 for (i = 0; i < 13; i++) {
102 struct surface3_ts_data_finger *finger;
103
104 finger = (struct surface3_ts_data_finger *)&data[17 +
105 i * sizeof(struct surface3_ts_data_finger)];
106
107
108
109
110
111
112
113 if (finger->status & 0x10)
114 break;
115
116 surface3_spi_report_touch(ts_data, finger);
117 }
118
119 input_mt_sync_frame(ts_data->input_dev);
120 input_sync(ts_data->input_dev);
121}
122
123static void surface3_spi_report_pen(struct surface3_ts_data *ts_data,
124 struct surface3_ts_data_pen *pen)
125{
126 struct input_dev *dev = ts_data->pen_input_dev;
127 int st = pen->status;
128 int prox = st & 0x01;
129 int rubber = st & 0x18;
130 int tool = (prox && rubber) ? BTN_TOOL_RUBBER : BTN_TOOL_PEN;
131
132
133 if (ts_data->pen_tool != tool) {
134 input_report_key(dev, ts_data->pen_tool, 0);
135 input_sync(dev);
136 ts_data->pen_tool = tool;
137 }
138
139 input_report_key(dev, BTN_TOUCH, st & 0x12);
140
141 input_report_key(dev, ts_data->pen_tool, prox);
142
143 if (st) {
144 input_report_key(dev,
145 BTN_STYLUS,
146 st & 0x04);
147
148 input_report_abs(dev,
149 ABS_X,
150 get_unaligned_le16(&pen->x));
151 input_report_abs(dev,
152 ABS_Y,
153 get_unaligned_le16(&pen->y));
154 input_report_abs(dev,
155 ABS_PRESSURE,
156 get_unaligned_le16(&pen->pressure));
157 }
158}
159
160static void surface3_spi_process_pen(struct surface3_ts_data *ts_data, u8 *data)
161{
162 struct surface3_ts_data_pen *pen;
163
164 pen = (struct surface3_ts_data_pen *)&data[15];
165
166 surface3_spi_report_pen(ts_data, pen);
167 input_sync(ts_data->pen_input_dev);
168}
169
170static void surface3_spi_process(struct surface3_ts_data *ts_data)
171{
172 static const char header[] = {
173 0xff, 0xff, 0xff, 0xff, 0xa5, 0x5a, 0xe7, 0x7e, 0x01
174 };
175 u8 *data = ts_data->rd_buf;
176
177 if (memcmp(header, data, sizeof(header)))
178 dev_err(&ts_data->spi->dev,
179 "%s header error: %*ph, ignoring...\n",
180 __func__, (int)sizeof(header), data);
181
182 switch (data[9]) {
183 case SURFACE3_REPORT_TOUCH:
184 surface3_spi_process_touch(ts_data, data);
185 break;
186 case SURFACE3_REPORT_PEN:
187 surface3_spi_process_pen(ts_data, data);
188 break;
189 default:
190 dev_err(&ts_data->spi->dev,
191 "%s unknown packet type: %x, ignoring...\n",
192 __func__, data[9]);
193 break;
194 }
195}
196
197static irqreturn_t surface3_spi_irq_handler(int irq, void *dev_id)
198{
199 struct surface3_ts_data *data = dev_id;
200
201 if (surface3_spi_read(data))
202 return IRQ_HANDLED;
203
204 dev_dbg(&data->spi->dev, "%s received -> %*ph\n",
205 __func__, SURFACE3_PACKET_SIZE, data->rd_buf);
206 surface3_spi_process(data);
207
208 return IRQ_HANDLED;
209}
210
211static void surface3_spi_power(struct surface3_ts_data *data, bool on)
212{
213 gpiod_set_value(data->gpiod_rst[0], on);
214 gpiod_set_value(data->gpiod_rst[1], on);
215
216 msleep(20);
217}
218
219
220
221
222
223
224static int surface3_spi_get_gpio_config(struct surface3_ts_data *data)
225{
226 int error;
227 struct device *dev;
228 struct gpio_desc *gpiod;
229 int i;
230
231 dev = &data->spi->dev;
232
233
234 for (i = 0; i < 2; i++) {
235 gpiod = devm_gpiod_get_index(dev, NULL, i, GPIOD_OUT_LOW);
236 if (IS_ERR(gpiod)) {
237 error = PTR_ERR(gpiod);
238 if (error != -EPROBE_DEFER)
239 dev_err(dev,
240 "Failed to get power GPIO %d: %d\n",
241 i,
242 error);
243 return error;
244 }
245
246 data->gpiod_rst[i] = gpiod;
247 }
248
249 return 0;
250}
251
252static int surface3_spi_create_touch_input(struct surface3_ts_data *data)
253{
254 struct input_dev *input;
255 int error;
256
257 input = devm_input_allocate_device(&data->spi->dev);
258 if (!input)
259 return -ENOMEM;
260
261 data->input_dev = input;
262
263 input_set_abs_params(input, ABS_MT_POSITION_X, 0, 9600, 0, 0);
264 input_abs_set_res(input, ABS_MT_POSITION_X, 40);
265 input_set_abs_params(input, ABS_MT_POSITION_Y, 0, 7200, 0, 0);
266 input_abs_set_res(input, ABS_MT_POSITION_Y, 48);
267 input_set_abs_params(input, ABS_MT_WIDTH_MAJOR, 0, 1024, 0, 0);
268 input_set_abs_params(input, ABS_MT_WIDTH_MINOR, 0, 1024, 0, 0);
269 input_mt_init_slots(input, 10, INPUT_MT_DIRECT);
270
271 input->name = "Surface3 SPI Capacitive TouchScreen";
272 input->phys = "input/ts";
273 input->id.bustype = BUS_SPI;
274 input->id.vendor = 0x045e;
275 input->id.product = 0x0001;
276 input->id.version = 0x0000;
277
278 error = input_register_device(input);
279 if (error) {
280 dev_err(&data->spi->dev,
281 "Failed to register input device: %d", error);
282 return error;
283 }
284
285 return 0;
286}
287
288static int surface3_spi_create_pen_input(struct surface3_ts_data *data)
289{
290 struct input_dev *input;
291 int error;
292
293 input = devm_input_allocate_device(&data->spi->dev);
294 if (!input)
295 return -ENOMEM;
296
297 data->pen_input_dev = input;
298 data->pen_tool = BTN_TOOL_PEN;
299
300 __set_bit(INPUT_PROP_DIRECT, input->propbit);
301 __set_bit(INPUT_PROP_POINTER, input->propbit);
302 input_set_abs_params(input, ABS_X, 0, 9600, 0, 0);
303 input_abs_set_res(input, ABS_X, 40);
304 input_set_abs_params(input, ABS_Y, 0, 7200, 0, 0);
305 input_abs_set_res(input, ABS_Y, 48);
306 input_set_abs_params(input, ABS_PRESSURE, 0, 1024, 0, 0);
307 input_set_capability(input, EV_KEY, BTN_TOUCH);
308 input_set_capability(input, EV_KEY, BTN_STYLUS);
309 input_set_capability(input, EV_KEY, BTN_TOOL_PEN);
310 input_set_capability(input, EV_KEY, BTN_TOOL_RUBBER);
311
312 input->name = "Surface3 SPI Pen Input";
313 input->phys = "input/ts";
314 input->id.bustype = BUS_SPI;
315 input->id.vendor = 0x045e;
316 input->id.product = 0x0002;
317 input->id.version = 0x0000;
318
319 error = input_register_device(input);
320 if (error) {
321 dev_err(&data->spi->dev,
322 "Failed to register input device: %d", error);
323 return error;
324 }
325
326 return 0;
327}
328
329static int surface3_spi_probe(struct spi_device *spi)
330{
331 struct surface3_ts_data *data;
332 int error;
333
334
335 spi->bits_per_word = 8;
336 spi->mode = SPI_MODE_0;
337 error = spi_setup(spi);
338 if (error)
339 return error;
340
341 data = devm_kzalloc(&spi->dev, sizeof(*data), GFP_KERNEL);
342 if (!data)
343 return -ENOMEM;
344
345 data->spi = spi;
346 spi_set_drvdata(spi, data);
347
348 error = surface3_spi_get_gpio_config(data);
349 if (error)
350 return error;
351
352 surface3_spi_power(data, true);
353 surface3_spi_power(data, false);
354 surface3_spi_power(data, true);
355
356 error = surface3_spi_create_touch_input(data);
357 if (error)
358 return error;
359
360 error = surface3_spi_create_pen_input(data);
361 if (error)
362 return error;
363
364 error = devm_request_threaded_irq(&spi->dev, spi->irq,
365 NULL, surface3_spi_irq_handler,
366 IRQF_ONESHOT,
367 "Surface3-irq", data);
368 if (error)
369 return error;
370
371 return 0;
372}
373
374static int __maybe_unused surface3_spi_suspend(struct device *dev)
375{
376 struct spi_device *spi = to_spi_device(dev);
377 struct surface3_ts_data *data = spi_get_drvdata(spi);
378
379 disable_irq(data->spi->irq);
380
381 surface3_spi_power(data, false);
382
383 return 0;
384}
385
386static int __maybe_unused surface3_spi_resume(struct device *dev)
387{
388 struct spi_device *spi = to_spi_device(dev);
389 struct surface3_ts_data *data = spi_get_drvdata(spi);
390
391 surface3_spi_power(data, true);
392
393 enable_irq(data->spi->irq);
394
395 return 0;
396}
397
398static SIMPLE_DEV_PM_OPS(surface3_spi_pm_ops,
399 surface3_spi_suspend,
400 surface3_spi_resume);
401
402#ifdef CONFIG_ACPI
403static const struct acpi_device_id surface3_spi_acpi_match[] = {
404 { "MSHW0037", 0 },
405 { }
406};
407MODULE_DEVICE_TABLE(acpi, surface3_spi_acpi_match);
408#endif
409
410static struct spi_driver surface3_spi_driver = {
411 .driver = {
412 .name = "Surface3-spi",
413 .acpi_match_table = ACPI_PTR(surface3_spi_acpi_match),
414 .pm = &surface3_spi_pm_ops,
415 },
416 .probe = surface3_spi_probe,
417};
418
419module_spi_driver(surface3_spi_driver);
420
421MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
422MODULE_DESCRIPTION("Surface 3 SPI touchscreen driver");
423MODULE_LICENSE("GPL v2");
424
