1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Driver for Ntrig/Microsoft Touchscreens over SPI |
4 | * |
5 | * Copyright (c) 2016 Red Hat Inc. |
6 | */ |
7 | |
8 | |
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 | |
28 | struct 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 | |
38 | struct 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 | |
50 | struct surface3_ts_data_pen { |
51 | u8 status; |
52 | __le16 x; |
53 | __le16 y; |
54 | __le16 pressure; |
55 | u8 padding; |
56 | } __packed; |
57 | |
58 | static 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, buf: ts_data->rd_buf, len: sizeof(ts_data->rd_buf)); |
64 | } |
65 | |
66 | static 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(dev: ts_data->input_dev, |
73 | key: get_unaligned_le16(p: &finger->tracking_id)); |
74 | if (slot < 0) |
75 | return; |
76 | |
77 | input_mt_slot(dev: ts_data->input_dev, slot); |
78 | input_mt_report_slot_state(dev: ts_data->input_dev, MT_TOOL_FINGER, active: st); |
79 | if (st) { |
80 | input_report_abs(dev: ts_data->input_dev, |
81 | ABS_MT_POSITION_X, |
82 | value: get_unaligned_le16(p: &finger->x)); |
83 | input_report_abs(dev: ts_data->input_dev, |
84 | ABS_MT_POSITION_Y, |
85 | value: get_unaligned_le16(p: &finger->y)); |
86 | input_report_abs(dev: ts_data->input_dev, |
87 | ABS_MT_WIDTH_MAJOR, |
88 | value: get_unaligned_le16(p: &finger->width)); |
89 | input_report_abs(dev: ts_data->input_dev, |
90 | ABS_MT_WIDTH_MINOR, |
91 | value: get_unaligned_le16(p: &finger->height)); |
92 | } |
93 | } |
94 | |
95 | static void surface3_spi_process_touch(struct surface3_ts_data *ts_data, u8 *data) |
96 | { |
97 | unsigned int i; |
98 | |
99 | for (i = 0; i < 13; i++) { |
100 | struct surface3_ts_data_finger *finger; |
101 | |
102 | finger = (struct surface3_ts_data_finger *)&data[17 + |
103 | i * sizeof(struct surface3_ts_data_finger)]; |
104 | |
105 | /* |
106 | * When bit 5 of status is 1, it marks the end of the report: |
107 | * - touch present: 0xe7 |
108 | * - touch released: 0xe4 |
109 | * - nothing valuable: 0xff |
110 | */ |
111 | if (finger->status & 0x10) |
112 | break; |
113 | |
114 | surface3_spi_report_touch(ts_data, finger); |
115 | } |
116 | |
117 | input_mt_sync_frame(dev: ts_data->input_dev); |
118 | input_sync(dev: ts_data->input_dev); |
119 | } |
120 | |
121 | static void surface3_spi_report_pen(struct surface3_ts_data *ts_data, |
122 | struct surface3_ts_data_pen *pen) |
123 | { |
124 | struct input_dev *dev = ts_data->pen_input_dev; |
125 | int st = pen->status; |
126 | int prox = st & 0x01; |
127 | int rubber = st & 0x18; |
128 | int tool = (prox && rubber) ? BTN_TOOL_RUBBER : BTN_TOOL_PEN; |
129 | |
130 | /* fake proximity out to switch tools */ |
131 | if (ts_data->pen_tool != tool) { |
132 | input_report_key(dev, code: ts_data->pen_tool, value: 0); |
133 | input_sync(dev); |
134 | ts_data->pen_tool = tool; |
135 | } |
136 | |
137 | input_report_key(dev, BTN_TOUCH, value: st & 0x12); |
138 | |
139 | input_report_key(dev, code: ts_data->pen_tool, value: prox); |
140 | |
141 | if (st) { |
142 | input_report_key(dev, |
143 | BTN_STYLUS, |
144 | value: st & 0x04); |
145 | |
146 | input_report_abs(dev, |
147 | ABS_X, |
148 | value: get_unaligned_le16(p: &pen->x)); |
149 | input_report_abs(dev, |
150 | ABS_Y, |
151 | value: get_unaligned_le16(p: &pen->y)); |
152 | input_report_abs(dev, |
153 | ABS_PRESSURE, |
154 | value: get_unaligned_le16(p: &pen->pressure)); |
155 | } |
156 | } |
157 | |
158 | static void surface3_spi_process_pen(struct surface3_ts_data *ts_data, u8 *data) |
159 | { |
160 | struct surface3_ts_data_pen *pen; |
161 | |
162 | pen = (struct surface3_ts_data_pen *)&data[15]; |
163 | |
164 | surface3_spi_report_pen(ts_data, pen); |
165 | input_sync(dev: ts_data->pen_input_dev); |
166 | } |
167 | |
168 | static void surface3_spi_process(struct surface3_ts_data *ts_data) |
169 | { |
170 | static const char [] = { |
171 | 0xff, 0xff, 0xff, 0xff, 0xa5, 0x5a, 0xe7, 0x7e, 0x01 |
172 | }; |
173 | u8 *data = ts_data->rd_buf; |
174 | |
175 | if (memcmp(p: header, q: data, size: sizeof(header))) |
176 | dev_err(&ts_data->spi->dev, |
177 | "%s header error: %*ph, ignoring...\n" , |
178 | __func__, (int)sizeof(header), data); |
179 | |
180 | switch (data[9]) { |
181 | case SURFACE3_REPORT_TOUCH: |
182 | surface3_spi_process_touch(ts_data, data); |
183 | break; |
184 | case SURFACE3_REPORT_PEN: |
185 | surface3_spi_process_pen(ts_data, data); |
186 | break; |
187 | default: |
188 | dev_err(&ts_data->spi->dev, |
189 | "%s unknown packet type: %x, ignoring...\n" , |
190 | __func__, data[9]); |
191 | break; |
192 | } |
193 | } |
194 | |
195 | static irqreturn_t surface3_spi_irq_handler(int irq, void *dev_id) |
196 | { |
197 | struct surface3_ts_data *data = dev_id; |
198 | |
199 | if (surface3_spi_read(ts_data: data)) |
200 | return IRQ_HANDLED; |
201 | |
202 | dev_dbg(&data->spi->dev, "%s received -> %*ph\n" , |
203 | __func__, SURFACE3_PACKET_SIZE, data->rd_buf); |
204 | surface3_spi_process(ts_data: data); |
205 | |
206 | return IRQ_HANDLED; |
207 | } |
208 | |
209 | static void surface3_spi_power(struct surface3_ts_data *data, bool on) |
210 | { |
211 | gpiod_set_value(desc: data->gpiod_rst[0], value: on); |
212 | gpiod_set_value(desc: data->gpiod_rst[1], value: on); |
213 | /* let the device settle a little */ |
214 | msleep(msecs: 20); |
215 | } |
216 | |
217 | /** |
218 | * surface3_spi_get_gpio_config - Get GPIO config from ACPI/DT |
219 | * |
220 | * @data: surface3_spi_ts_data pointer |
221 | */ |
222 | static int surface3_spi_get_gpio_config(struct surface3_ts_data *data) |
223 | { |
224 | struct device *dev; |
225 | struct gpio_desc *gpiod; |
226 | int i; |
227 | |
228 | dev = &data->spi->dev; |
229 | |
230 | /* Get the reset lines GPIO pin number */ |
231 | for (i = 0; i < 2; i++) { |
232 | gpiod = devm_gpiod_get_index(dev, NULL, idx: i, flags: GPIOD_OUT_LOW); |
233 | if (IS_ERR(ptr: gpiod)) |
234 | return dev_err_probe(dev, err: PTR_ERR(ptr: gpiod), |
235 | fmt: "Failed to get power GPIO %d\n" , i); |
236 | |
237 | data->gpiod_rst[i] = gpiod; |
238 | } |
239 | |
240 | return 0; |
241 | } |
242 | |
243 | static int surface3_spi_create_touch_input(struct surface3_ts_data *data) |
244 | { |
245 | struct input_dev *input; |
246 | int error; |
247 | |
248 | input = devm_input_allocate_device(&data->spi->dev); |
249 | if (!input) |
250 | return -ENOMEM; |
251 | |
252 | data->input_dev = input; |
253 | |
254 | input_set_abs_params(dev: input, ABS_MT_POSITION_X, min: 0, max: 9600, fuzz: 0, flat: 0); |
255 | input_abs_set_res(dev: input, ABS_MT_POSITION_X, val: 40); |
256 | input_set_abs_params(dev: input, ABS_MT_POSITION_Y, min: 0, max: 7200, fuzz: 0, flat: 0); |
257 | input_abs_set_res(dev: input, ABS_MT_POSITION_Y, val: 48); |
258 | input_set_abs_params(dev: input, ABS_MT_WIDTH_MAJOR, min: 0, max: 1024, fuzz: 0, flat: 0); |
259 | input_set_abs_params(dev: input, ABS_MT_WIDTH_MINOR, min: 0, max: 1024, fuzz: 0, flat: 0); |
260 | input_mt_init_slots(dev: input, num_slots: 10, INPUT_MT_DIRECT); |
261 | |
262 | input->name = "Surface3 SPI Capacitive TouchScreen" ; |
263 | input->phys = "input/ts" ; |
264 | input->id.bustype = BUS_SPI; |
265 | input->id.vendor = 0x045e; /* Microsoft */ |
266 | input->id.product = 0x0001; |
267 | input->id.version = 0x0000; |
268 | |
269 | error = input_register_device(input); |
270 | if (error) { |
271 | dev_err(&data->spi->dev, |
272 | "Failed to register input device: %d" , error); |
273 | return error; |
274 | } |
275 | |
276 | return 0; |
277 | } |
278 | |
279 | static int surface3_spi_create_pen_input(struct surface3_ts_data *data) |
280 | { |
281 | struct input_dev *input; |
282 | int error; |
283 | |
284 | input = devm_input_allocate_device(&data->spi->dev); |
285 | if (!input) |
286 | return -ENOMEM; |
287 | |
288 | data->pen_input_dev = input; |
289 | data->pen_tool = BTN_TOOL_PEN; |
290 | |
291 | __set_bit(INPUT_PROP_DIRECT, input->propbit); |
292 | __set_bit(INPUT_PROP_POINTER, input->propbit); |
293 | input_set_abs_params(dev: input, ABS_X, min: 0, max: 9600, fuzz: 0, flat: 0); |
294 | input_abs_set_res(dev: input, ABS_X, val: 40); |
295 | input_set_abs_params(dev: input, ABS_Y, min: 0, max: 7200, fuzz: 0, flat: 0); |
296 | input_abs_set_res(dev: input, ABS_Y, val: 48); |
297 | input_set_abs_params(dev: input, ABS_PRESSURE, min: 0, max: 1024, fuzz: 0, flat: 0); |
298 | input_set_capability(dev: input, EV_KEY, BTN_TOUCH); |
299 | input_set_capability(dev: input, EV_KEY, BTN_STYLUS); |
300 | input_set_capability(dev: input, EV_KEY, BTN_TOOL_PEN); |
301 | input_set_capability(dev: input, EV_KEY, BTN_TOOL_RUBBER); |
302 | |
303 | input->name = "Surface3 SPI Pen Input" ; |
304 | input->phys = "input/ts" ; |
305 | input->id.bustype = BUS_SPI; |
306 | input->id.vendor = 0x045e; /* Microsoft */ |
307 | input->id.product = 0x0002; |
308 | input->id.version = 0x0000; |
309 | |
310 | error = input_register_device(input); |
311 | if (error) { |
312 | dev_err(&data->spi->dev, |
313 | "Failed to register input device: %d" , error); |
314 | return error; |
315 | } |
316 | |
317 | return 0; |
318 | } |
319 | |
320 | static int surface3_spi_probe(struct spi_device *spi) |
321 | { |
322 | struct surface3_ts_data *data; |
323 | int error; |
324 | |
325 | /* Set up SPI*/ |
326 | spi->bits_per_word = 8; |
327 | spi->mode = SPI_MODE_0; |
328 | error = spi_setup(spi); |
329 | if (error) |
330 | return error; |
331 | |
332 | data = devm_kzalloc(dev: &spi->dev, size: sizeof(*data), GFP_KERNEL); |
333 | if (!data) |
334 | return -ENOMEM; |
335 | |
336 | data->spi = spi; |
337 | spi_set_drvdata(spi, data); |
338 | |
339 | error = surface3_spi_get_gpio_config(data); |
340 | if (error) |
341 | return error; |
342 | |
343 | surface3_spi_power(data, on: true); |
344 | surface3_spi_power(data, on: false); |
345 | surface3_spi_power(data, on: true); |
346 | |
347 | error = surface3_spi_create_touch_input(data); |
348 | if (error) |
349 | return error; |
350 | |
351 | error = surface3_spi_create_pen_input(data); |
352 | if (error) |
353 | return error; |
354 | |
355 | error = devm_request_threaded_irq(dev: &spi->dev, irq: spi->irq, |
356 | NULL, thread_fn: surface3_spi_irq_handler, |
357 | IRQF_ONESHOT, |
358 | devname: "Surface3-irq" , dev_id: data); |
359 | if (error) |
360 | return error; |
361 | |
362 | return 0; |
363 | } |
364 | |
365 | static int surface3_spi_suspend(struct device *dev) |
366 | { |
367 | struct spi_device *spi = to_spi_device(dev); |
368 | struct surface3_ts_data *data = spi_get_drvdata(spi); |
369 | |
370 | disable_irq(irq: data->spi->irq); |
371 | |
372 | surface3_spi_power(data, on: false); |
373 | |
374 | return 0; |
375 | } |
376 | |
377 | static int surface3_spi_resume(struct device *dev) |
378 | { |
379 | struct spi_device *spi = to_spi_device(dev); |
380 | struct surface3_ts_data *data = spi_get_drvdata(spi); |
381 | |
382 | surface3_spi_power(data, on: true); |
383 | |
384 | enable_irq(irq: data->spi->irq); |
385 | |
386 | return 0; |
387 | } |
388 | |
389 | static DEFINE_SIMPLE_DEV_PM_OPS(surface3_spi_pm_ops, |
390 | surface3_spi_suspend, |
391 | surface3_spi_resume); |
392 | |
393 | #ifdef CONFIG_ACPI |
394 | static const struct acpi_device_id surface3_spi_acpi_match[] = { |
395 | { "MSHW0037" , 0 }, |
396 | { } |
397 | }; |
398 | MODULE_DEVICE_TABLE(acpi, surface3_spi_acpi_match); |
399 | #endif |
400 | |
401 | static struct spi_driver surface3_spi_driver = { |
402 | .driver = { |
403 | .name = "Surface3-spi" , |
404 | .acpi_match_table = ACPI_PTR(surface3_spi_acpi_match), |
405 | .pm = pm_sleep_ptr(&surface3_spi_pm_ops), |
406 | }, |
407 | .probe = surface3_spi_probe, |
408 | }; |
409 | |
410 | module_spi_driver(surface3_spi_driver); |
411 | |
412 | MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>" ); |
413 | MODULE_DESCRIPTION("Surface 3 SPI touchscreen driver" ); |
414 | MODULE_LICENSE("GPL v2" ); |
415 | |