1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (C) 2006-2008 Michael Hennerich, Analog Devices Inc. |
4 | * |
5 | * Description: AD7877 based touchscreen, sensor (ADCs), DAC and GPIO driver |
6 | * Based on: ads7846.c |
7 | * |
8 | * Bugs: Enter bugs at http://blackfin.uclinux.org/ |
9 | * |
10 | * History: |
11 | * Copyright (c) 2005 David Brownell |
12 | * Copyright (c) 2006 Nokia Corporation |
13 | * Various changes: Imre Deak <imre.deak@nokia.com> |
14 | * |
15 | * Using code from: |
16 | * - corgi_ts.c |
17 | * Copyright (C) 2004-2005 Richard Purdie |
18 | * - omap_ts.[hc], ads7846.h, ts_osk.c |
19 | * Copyright (C) 2002 MontaVista Software |
20 | * Copyright (C) 2004 Texas Instruments |
21 | * Copyright (C) 2005 Dirk Behme |
22 | */ |
23 | |
24 | |
25 | #include <linux/device.h> |
26 | #include <linux/delay.h> |
27 | #include <linux/input.h> |
28 | #include <linux/interrupt.h> |
29 | #include <linux/pm.h> |
30 | #include <linux/slab.h> |
31 | #include <linux/spi/spi.h> |
32 | #include <linux/spi/ad7877.h> |
33 | #include <linux/module.h> |
34 | #include <asm/irq.h> |
35 | |
36 | #define TS_PEN_UP_TIMEOUT msecs_to_jiffies(100) |
37 | |
38 | #define MAX_SPI_FREQ_HZ 20000000 |
39 | #define MAX_12BIT ((1<<12)-1) |
40 | |
41 | #define AD7877_REG_ZEROS 0 |
42 | #define AD7877_REG_CTRL1 1 |
43 | #define AD7877_REG_CTRL2 2 |
44 | #define AD7877_REG_ALERT 3 |
45 | #define AD7877_REG_AUX1HIGH 4 |
46 | #define AD7877_REG_AUX1LOW 5 |
47 | #define AD7877_REG_BAT1HIGH 6 |
48 | #define AD7877_REG_BAT1LOW 7 |
49 | #define AD7877_REG_BAT2HIGH 8 |
50 | #define AD7877_REG_BAT2LOW 9 |
51 | #define AD7877_REG_TEMP1HIGH 10 |
52 | #define AD7877_REG_TEMP1LOW 11 |
53 | #define AD7877_REG_SEQ0 12 |
54 | #define AD7877_REG_SEQ1 13 |
55 | #define AD7877_REG_DAC 14 |
56 | #define AD7877_REG_NONE1 15 |
57 | #define AD7877_REG_EXTWRITE 15 |
58 | #define AD7877_REG_XPLUS 16 |
59 | #define AD7877_REG_YPLUS 17 |
60 | #define AD7877_REG_Z2 18 |
61 | #define AD7877_REG_aux1 19 |
62 | #define AD7877_REG_aux2 20 |
63 | #define AD7877_REG_aux3 21 |
64 | #define AD7877_REG_bat1 22 |
65 | #define AD7877_REG_bat2 23 |
66 | #define AD7877_REG_temp1 24 |
67 | #define AD7877_REG_temp2 25 |
68 | #define AD7877_REG_Z1 26 |
69 | #define AD7877_REG_GPIOCTRL1 27 |
70 | #define AD7877_REG_GPIOCTRL2 28 |
71 | #define AD7877_REG_GPIODATA 29 |
72 | #define AD7877_REG_NONE2 30 |
73 | #define AD7877_REG_NONE3 31 |
74 | |
75 | #define AD7877_SEQ_YPLUS_BIT (1<<11) |
76 | #define AD7877_SEQ_XPLUS_BIT (1<<10) |
77 | #define AD7877_SEQ_Z2_BIT (1<<9) |
78 | #define AD7877_SEQ_AUX1_BIT (1<<8) |
79 | #define AD7877_SEQ_AUX2_BIT (1<<7) |
80 | #define AD7877_SEQ_AUX3_BIT (1<<6) |
81 | #define AD7877_SEQ_BAT1_BIT (1<<5) |
82 | #define AD7877_SEQ_BAT2_BIT (1<<4) |
83 | #define AD7877_SEQ_TEMP1_BIT (1<<3) |
84 | #define AD7877_SEQ_TEMP2_BIT (1<<2) |
85 | #define AD7877_SEQ_Z1_BIT (1<<1) |
86 | |
87 | enum { |
88 | AD7877_SEQ_YPOS = 0, |
89 | AD7877_SEQ_XPOS = 1, |
90 | AD7877_SEQ_Z2 = 2, |
91 | AD7877_SEQ_AUX1 = 3, |
92 | AD7877_SEQ_AUX2 = 4, |
93 | AD7877_SEQ_AUX3 = 5, |
94 | AD7877_SEQ_BAT1 = 6, |
95 | AD7877_SEQ_BAT2 = 7, |
96 | AD7877_SEQ_TEMP1 = 8, |
97 | AD7877_SEQ_TEMP2 = 9, |
98 | AD7877_SEQ_Z1 = 10, |
99 | AD7877_NR_SENSE = 11, |
100 | }; |
101 | |
102 | /* DAC Register Default RANGE 0 to Vcc, Volatge Mode, DAC On */ |
103 | #define AD7877_DAC_CONF 0x1 |
104 | |
105 | /* If gpio3 is set AUX3/GPIO3 acts as GPIO Output */ |
106 | #define AD7877_EXTW_GPIO_3_CONF 0x1C4 |
107 | #define AD7877_EXTW_GPIO_DATA 0x200 |
108 | |
109 | /* Control REG 2 */ |
110 | #define AD7877_TMR(x) ((x & 0x3) << 0) |
111 | #define AD7877_REF(x) ((x & 0x1) << 2) |
112 | #define AD7877_POL(x) ((x & 0x1) << 3) |
113 | #define AD7877_FCD(x) ((x & 0x3) << 4) |
114 | #define AD7877_PM(x) ((x & 0x3) << 6) |
115 | #define AD7877_ACQ(x) ((x & 0x3) << 8) |
116 | #define AD7877_AVG(x) ((x & 0x3) << 10) |
117 | |
118 | /* Control REG 1 */ |
119 | #define AD7877_SER (1 << 11) /* non-differential */ |
120 | #define AD7877_DFR (0 << 11) /* differential */ |
121 | |
122 | #define AD7877_MODE_NOC (0) /* Do not convert */ |
123 | #define AD7877_MODE_SCC (1) /* Single channel conversion */ |
124 | #define AD7877_MODE_SEQ0 (2) /* Sequence 0 in Slave Mode */ |
125 | #define AD7877_MODE_SEQ1 (3) /* Sequence 1 in Master Mode */ |
126 | |
127 | #define AD7877_CHANADD(x) ((x&0xF)<<7) |
128 | #define AD7877_READADD(x) ((x)<<2) |
129 | #define AD7877_WRITEADD(x) ((x)<<12) |
130 | |
131 | #define AD7877_READ_CHAN(x) (AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_SER | \ |
132 | AD7877_MODE_SCC | AD7877_CHANADD(AD7877_REG_ ## x) | \ |
133 | AD7877_READADD(AD7877_REG_ ## x)) |
134 | |
135 | #define AD7877_MM_SEQUENCE (AD7877_SEQ_YPLUS_BIT | AD7877_SEQ_XPLUS_BIT | \ |
136 | AD7877_SEQ_Z2_BIT | AD7877_SEQ_Z1_BIT) |
137 | |
138 | /* |
139 | * Non-touchscreen sensors only use single-ended conversions. |
140 | */ |
141 | |
142 | struct ser_req { |
143 | u16 reset; |
144 | u16 ref_on; |
145 | u16 command; |
146 | struct spi_message msg; |
147 | struct spi_transfer xfer[6]; |
148 | |
149 | /* |
150 | * DMA (thus cache coherency maintenance) requires the |
151 | * transfer buffers to live in their own cache lines. |
152 | */ |
153 | u16 sample ____cacheline_aligned; |
154 | }; |
155 | |
156 | struct ad7877 { |
157 | struct input_dev *input; |
158 | char phys[32]; |
159 | |
160 | struct spi_device *spi; |
161 | u16 model; |
162 | u16 vref_delay_usecs; |
163 | u16 x_plate_ohms; |
164 | u16 pressure_max; |
165 | |
166 | u16 cmd_crtl1; |
167 | u16 cmd_crtl2; |
168 | u16 cmd_dummy; |
169 | u16 dac; |
170 | |
171 | u8 stopacq_polarity; |
172 | u8 first_conversion_delay; |
173 | u8 acquisition_time; |
174 | u8 averaging; |
175 | u8 pen_down_acc_interval; |
176 | |
177 | struct spi_transfer xfer[AD7877_NR_SENSE + 2]; |
178 | struct spi_message msg; |
179 | |
180 | struct mutex mutex; |
181 | bool disabled; /* P: mutex */ |
182 | bool gpio3; /* P: mutex */ |
183 | bool gpio4; /* P: mutex */ |
184 | |
185 | spinlock_t lock; |
186 | struct timer_list timer; /* P: lock */ |
187 | |
188 | /* |
189 | * DMA (thus cache coherency maintenance) requires the |
190 | * transfer buffers to live in their own cache lines. |
191 | */ |
192 | u16 conversion_data[AD7877_NR_SENSE] ____cacheline_aligned; |
193 | }; |
194 | |
195 | static bool gpio3; |
196 | module_param(gpio3, bool, 0); |
197 | MODULE_PARM_DESC(gpio3, "If gpio3 is set to 1 AUX3 acts as GPIO3" ); |
198 | |
199 | static int ad7877_read(struct spi_device *spi, u16 reg) |
200 | { |
201 | struct ser_req *req; |
202 | int status, ret; |
203 | |
204 | req = kzalloc(size: sizeof *req, GFP_KERNEL); |
205 | if (!req) |
206 | return -ENOMEM; |
207 | |
208 | spi_message_init(m: &req->msg); |
209 | |
210 | req->command = (u16) (AD7877_WRITEADD(AD7877_REG_CTRL1) | |
211 | AD7877_READADD(reg)); |
212 | req->xfer[0].tx_buf = &req->command; |
213 | req->xfer[0].len = 2; |
214 | req->xfer[0].cs_change = 1; |
215 | |
216 | req->xfer[1].rx_buf = &req->sample; |
217 | req->xfer[1].len = 2; |
218 | |
219 | spi_message_add_tail(t: &req->xfer[0], m: &req->msg); |
220 | spi_message_add_tail(t: &req->xfer[1], m: &req->msg); |
221 | |
222 | status = spi_sync(spi, message: &req->msg); |
223 | ret = status ? : req->sample; |
224 | |
225 | kfree(objp: req); |
226 | |
227 | return ret; |
228 | } |
229 | |
230 | static int ad7877_write(struct spi_device *spi, u16 reg, u16 val) |
231 | { |
232 | struct ser_req *req; |
233 | int status; |
234 | |
235 | req = kzalloc(size: sizeof *req, GFP_KERNEL); |
236 | if (!req) |
237 | return -ENOMEM; |
238 | |
239 | spi_message_init(m: &req->msg); |
240 | |
241 | req->command = (u16) (AD7877_WRITEADD(reg) | (val & MAX_12BIT)); |
242 | req->xfer[0].tx_buf = &req->command; |
243 | req->xfer[0].len = 2; |
244 | |
245 | spi_message_add_tail(t: &req->xfer[0], m: &req->msg); |
246 | |
247 | status = spi_sync(spi, message: &req->msg); |
248 | |
249 | kfree(objp: req); |
250 | |
251 | return status; |
252 | } |
253 | |
254 | static int ad7877_read_adc(struct spi_device *spi, unsigned command) |
255 | { |
256 | struct ad7877 *ts = spi_get_drvdata(spi); |
257 | struct ser_req *req; |
258 | int status; |
259 | int sample; |
260 | int i; |
261 | |
262 | req = kzalloc(size: sizeof *req, GFP_KERNEL); |
263 | if (!req) |
264 | return -ENOMEM; |
265 | |
266 | spi_message_init(m: &req->msg); |
267 | |
268 | /* activate reference, so it has time to settle; */ |
269 | req->ref_on = AD7877_WRITEADD(AD7877_REG_CTRL2) | |
270 | AD7877_POL(ts->stopacq_polarity) | |
271 | AD7877_AVG(0) | AD7877_PM(2) | AD7877_TMR(0) | |
272 | AD7877_ACQ(ts->acquisition_time) | AD7877_FCD(0); |
273 | |
274 | req->reset = AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_MODE_NOC; |
275 | |
276 | req->command = (u16) command; |
277 | |
278 | req->xfer[0].tx_buf = &req->reset; |
279 | req->xfer[0].len = 2; |
280 | req->xfer[0].cs_change = 1; |
281 | |
282 | req->xfer[1].tx_buf = &req->ref_on; |
283 | req->xfer[1].len = 2; |
284 | req->xfer[1].delay.value = ts->vref_delay_usecs; |
285 | req->xfer[1].delay.unit = SPI_DELAY_UNIT_USECS; |
286 | req->xfer[1].cs_change = 1; |
287 | |
288 | req->xfer[2].tx_buf = &req->command; |
289 | req->xfer[2].len = 2; |
290 | req->xfer[2].delay.value = ts->vref_delay_usecs; |
291 | req->xfer[2].delay.unit = SPI_DELAY_UNIT_USECS; |
292 | req->xfer[2].cs_change = 1; |
293 | |
294 | req->xfer[3].rx_buf = &req->sample; |
295 | req->xfer[3].len = 2; |
296 | req->xfer[3].cs_change = 1; |
297 | |
298 | req->xfer[4].tx_buf = &ts->cmd_crtl2; /*REF OFF*/ |
299 | req->xfer[4].len = 2; |
300 | req->xfer[4].cs_change = 1; |
301 | |
302 | req->xfer[5].tx_buf = &ts->cmd_crtl1; /*DEFAULT*/ |
303 | req->xfer[5].len = 2; |
304 | |
305 | /* group all the transfers together, so we can't interfere with |
306 | * reading touchscreen state; disable penirq while sampling |
307 | */ |
308 | for (i = 0; i < 6; i++) |
309 | spi_message_add_tail(t: &req->xfer[i], m: &req->msg); |
310 | |
311 | status = spi_sync(spi, message: &req->msg); |
312 | sample = req->sample; |
313 | |
314 | kfree(objp: req); |
315 | |
316 | return status ? : sample; |
317 | } |
318 | |
319 | static int ad7877_process_data(struct ad7877 *ts) |
320 | { |
321 | struct input_dev *input_dev = ts->input; |
322 | unsigned Rt; |
323 | u16 x, y, z1, z2; |
324 | |
325 | x = ts->conversion_data[AD7877_SEQ_XPOS] & MAX_12BIT; |
326 | y = ts->conversion_data[AD7877_SEQ_YPOS] & MAX_12BIT; |
327 | z1 = ts->conversion_data[AD7877_SEQ_Z1] & MAX_12BIT; |
328 | z2 = ts->conversion_data[AD7877_SEQ_Z2] & MAX_12BIT; |
329 | |
330 | /* |
331 | * The samples processed here are already preprocessed by the AD7877. |
332 | * The preprocessing function consists of an averaging filter. |
333 | * The combination of 'first conversion delay' and averaging provides a robust solution, |
334 | * discarding the spurious noise in the signal and keeping only the data of interest. |
335 | * The size of the averaging filter is programmable. (dev.platform_data, see linux/spi/ad7877.h) |
336 | * Other user-programmable conversion controls include variable acquisition time, |
337 | * and first conversion delay. Up to 16 averages can be taken per conversion. |
338 | */ |
339 | |
340 | if (likely(x && z1)) { |
341 | /* compute touch pressure resistance using equation #1 */ |
342 | Rt = (z2 - z1) * x * ts->x_plate_ohms; |
343 | Rt /= z1; |
344 | Rt = (Rt + 2047) >> 12; |
345 | |
346 | /* |
347 | * Sample found inconsistent, pressure is beyond |
348 | * the maximum. Don't report it to user space. |
349 | */ |
350 | if (Rt > ts->pressure_max) |
351 | return -EINVAL; |
352 | |
353 | if (!timer_pending(timer: &ts->timer)) |
354 | input_report_key(dev: input_dev, BTN_TOUCH, value: 1); |
355 | |
356 | input_report_abs(dev: input_dev, ABS_X, value: x); |
357 | input_report_abs(dev: input_dev, ABS_Y, value: y); |
358 | input_report_abs(dev: input_dev, ABS_PRESSURE, value: Rt); |
359 | input_sync(dev: input_dev); |
360 | |
361 | return 0; |
362 | } |
363 | |
364 | return -EINVAL; |
365 | } |
366 | |
367 | static inline void ad7877_ts_event_release(struct ad7877 *ts) |
368 | { |
369 | struct input_dev *input_dev = ts->input; |
370 | |
371 | input_report_abs(dev: input_dev, ABS_PRESSURE, value: 0); |
372 | input_report_key(dev: input_dev, BTN_TOUCH, value: 0); |
373 | input_sync(dev: input_dev); |
374 | } |
375 | |
376 | static void ad7877_timer(struct timer_list *t) |
377 | { |
378 | struct ad7877 *ts = from_timer(ts, t, timer); |
379 | unsigned long flags; |
380 | |
381 | spin_lock_irqsave(&ts->lock, flags); |
382 | ad7877_ts_event_release(ts); |
383 | spin_unlock_irqrestore(lock: &ts->lock, flags); |
384 | } |
385 | |
386 | static irqreturn_t ad7877_irq(int irq, void *handle) |
387 | { |
388 | struct ad7877 *ts = handle; |
389 | unsigned long flags; |
390 | int error; |
391 | |
392 | error = spi_sync(spi: ts->spi, message: &ts->msg); |
393 | if (error) { |
394 | dev_err(&ts->spi->dev, "spi_sync --> %d\n" , error); |
395 | goto out; |
396 | } |
397 | |
398 | spin_lock_irqsave(&ts->lock, flags); |
399 | error = ad7877_process_data(ts); |
400 | if (!error) |
401 | mod_timer(timer: &ts->timer, expires: jiffies + TS_PEN_UP_TIMEOUT); |
402 | spin_unlock_irqrestore(lock: &ts->lock, flags); |
403 | |
404 | out: |
405 | return IRQ_HANDLED; |
406 | } |
407 | |
408 | static void ad7877_disable(void *data) |
409 | { |
410 | struct ad7877 *ts = data; |
411 | |
412 | mutex_lock(&ts->mutex); |
413 | |
414 | if (!ts->disabled) { |
415 | ts->disabled = true; |
416 | disable_irq(irq: ts->spi->irq); |
417 | |
418 | if (del_timer_sync(timer: &ts->timer)) |
419 | ad7877_ts_event_release(ts); |
420 | } |
421 | |
422 | /* |
423 | * We know the chip's in lowpower mode since we always |
424 | * leave it that way after every request |
425 | */ |
426 | |
427 | mutex_unlock(lock: &ts->mutex); |
428 | } |
429 | |
430 | static void ad7877_enable(struct ad7877 *ts) |
431 | { |
432 | mutex_lock(&ts->mutex); |
433 | |
434 | if (ts->disabled) { |
435 | ts->disabled = false; |
436 | enable_irq(irq: ts->spi->irq); |
437 | } |
438 | |
439 | mutex_unlock(lock: &ts->mutex); |
440 | } |
441 | |
442 | #define SHOW(name) static ssize_t \ |
443 | name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \ |
444 | { \ |
445 | struct ad7877 *ts = dev_get_drvdata(dev); \ |
446 | ssize_t v = ad7877_read_adc(ts->spi, \ |
447 | AD7877_READ_CHAN(name)); \ |
448 | if (v < 0) \ |
449 | return v; \ |
450 | return sprintf(buf, "%u\n", (unsigned) v); \ |
451 | } \ |
452 | static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL); |
453 | |
454 | SHOW(aux1) |
455 | SHOW(aux2) |
456 | SHOW(aux3) |
457 | SHOW(bat1) |
458 | SHOW(bat2) |
459 | SHOW(temp1) |
460 | SHOW(temp2) |
461 | |
462 | static ssize_t ad7877_disable_show(struct device *dev, |
463 | struct device_attribute *attr, char *buf) |
464 | { |
465 | struct ad7877 *ts = dev_get_drvdata(dev); |
466 | |
467 | return sprintf(buf, fmt: "%u\n" , ts->disabled); |
468 | } |
469 | |
470 | static ssize_t ad7877_disable_store(struct device *dev, |
471 | struct device_attribute *attr, |
472 | const char *buf, size_t count) |
473 | { |
474 | struct ad7877 *ts = dev_get_drvdata(dev); |
475 | unsigned int val; |
476 | int error; |
477 | |
478 | error = kstrtouint(s: buf, base: 10, res: &val); |
479 | if (error) |
480 | return error; |
481 | |
482 | if (val) |
483 | ad7877_disable(data: ts); |
484 | else |
485 | ad7877_enable(ts); |
486 | |
487 | return count; |
488 | } |
489 | |
490 | static DEVICE_ATTR(disable, 0664, ad7877_disable_show, ad7877_disable_store); |
491 | |
492 | static ssize_t ad7877_dac_show(struct device *dev, |
493 | struct device_attribute *attr, char *buf) |
494 | { |
495 | struct ad7877 *ts = dev_get_drvdata(dev); |
496 | |
497 | return sprintf(buf, fmt: "%u\n" , ts->dac); |
498 | } |
499 | |
500 | static ssize_t ad7877_dac_store(struct device *dev, |
501 | struct device_attribute *attr, |
502 | const char *buf, size_t count) |
503 | { |
504 | struct ad7877 *ts = dev_get_drvdata(dev); |
505 | unsigned int val; |
506 | int error; |
507 | |
508 | error = kstrtouint(s: buf, base: 10, res: &val); |
509 | if (error) |
510 | return error; |
511 | |
512 | mutex_lock(&ts->mutex); |
513 | ts->dac = val & 0xFF; |
514 | ad7877_write(spi: ts->spi, AD7877_REG_DAC, val: (ts->dac << 4) | AD7877_DAC_CONF); |
515 | mutex_unlock(lock: &ts->mutex); |
516 | |
517 | return count; |
518 | } |
519 | |
520 | static DEVICE_ATTR(dac, 0664, ad7877_dac_show, ad7877_dac_store); |
521 | |
522 | static ssize_t ad7877_gpio3_show(struct device *dev, |
523 | struct device_attribute *attr, char *buf) |
524 | { |
525 | struct ad7877 *ts = dev_get_drvdata(dev); |
526 | |
527 | return sprintf(buf, fmt: "%u\n" , ts->gpio3); |
528 | } |
529 | |
530 | static ssize_t ad7877_gpio3_store(struct device *dev, |
531 | struct device_attribute *attr, |
532 | const char *buf, size_t count) |
533 | { |
534 | struct ad7877 *ts = dev_get_drvdata(dev); |
535 | unsigned int val; |
536 | int error; |
537 | |
538 | error = kstrtouint(s: buf, base: 10, res: &val); |
539 | if (error) |
540 | return error; |
541 | |
542 | mutex_lock(&ts->mutex); |
543 | ts->gpio3 = !!val; |
544 | ad7877_write(spi: ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA | |
545 | (ts->gpio4 << 4) | (ts->gpio3 << 5)); |
546 | mutex_unlock(lock: &ts->mutex); |
547 | |
548 | return count; |
549 | } |
550 | |
551 | static DEVICE_ATTR(gpio3, 0664, ad7877_gpio3_show, ad7877_gpio3_store); |
552 | |
553 | static ssize_t ad7877_gpio4_show(struct device *dev, |
554 | struct device_attribute *attr, char *buf) |
555 | { |
556 | struct ad7877 *ts = dev_get_drvdata(dev); |
557 | |
558 | return sprintf(buf, fmt: "%u\n" , ts->gpio4); |
559 | } |
560 | |
561 | static ssize_t ad7877_gpio4_store(struct device *dev, |
562 | struct device_attribute *attr, |
563 | const char *buf, size_t count) |
564 | { |
565 | struct ad7877 *ts = dev_get_drvdata(dev); |
566 | unsigned int val; |
567 | int error; |
568 | |
569 | error = kstrtouint(s: buf, base: 10, res: &val); |
570 | if (error) |
571 | return error; |
572 | |
573 | mutex_lock(&ts->mutex); |
574 | ts->gpio4 = !!val; |
575 | ad7877_write(spi: ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA | |
576 | (ts->gpio4 << 4) | (ts->gpio3 << 5)); |
577 | mutex_unlock(lock: &ts->mutex); |
578 | |
579 | return count; |
580 | } |
581 | |
582 | static DEVICE_ATTR(gpio4, 0664, ad7877_gpio4_show, ad7877_gpio4_store); |
583 | |
584 | static struct attribute *ad7877_attributes[] = { |
585 | &dev_attr_temp1.attr, |
586 | &dev_attr_temp2.attr, |
587 | &dev_attr_aux1.attr, |
588 | &dev_attr_aux2.attr, |
589 | &dev_attr_aux3.attr, |
590 | &dev_attr_bat1.attr, |
591 | &dev_attr_bat2.attr, |
592 | &dev_attr_disable.attr, |
593 | &dev_attr_dac.attr, |
594 | &dev_attr_gpio3.attr, |
595 | &dev_attr_gpio4.attr, |
596 | NULL |
597 | }; |
598 | |
599 | static umode_t ad7877_attr_is_visible(struct kobject *kobj, |
600 | struct attribute *attr, int n) |
601 | { |
602 | umode_t mode = attr->mode; |
603 | |
604 | if (attr == &dev_attr_aux3.attr) { |
605 | if (gpio3) |
606 | mode = 0; |
607 | } else if (attr == &dev_attr_gpio3.attr) { |
608 | if (!gpio3) |
609 | mode = 0; |
610 | } |
611 | |
612 | return mode; |
613 | } |
614 | |
615 | static const struct attribute_group ad7877_attr_group = { |
616 | .is_visible = ad7877_attr_is_visible, |
617 | .attrs = ad7877_attributes, |
618 | }; |
619 | |
620 | static void ad7877_setup_ts_def_msg(struct spi_device *spi, struct ad7877 *ts) |
621 | { |
622 | struct spi_message *m; |
623 | int i; |
624 | |
625 | ts->cmd_crtl2 = AD7877_WRITEADD(AD7877_REG_CTRL2) | |
626 | AD7877_POL(ts->stopacq_polarity) | |
627 | AD7877_AVG(ts->averaging) | AD7877_PM(1) | |
628 | AD7877_TMR(ts->pen_down_acc_interval) | |
629 | AD7877_ACQ(ts->acquisition_time) | |
630 | AD7877_FCD(ts->first_conversion_delay); |
631 | |
632 | ad7877_write(spi, AD7877_REG_CTRL2, val: ts->cmd_crtl2); |
633 | |
634 | ts->cmd_crtl1 = AD7877_WRITEADD(AD7877_REG_CTRL1) | |
635 | AD7877_READADD(AD7877_REG_XPLUS-1) | |
636 | AD7877_MODE_SEQ1 | AD7877_DFR; |
637 | |
638 | ad7877_write(spi, AD7877_REG_CTRL1, val: ts->cmd_crtl1); |
639 | |
640 | ts->cmd_dummy = 0; |
641 | |
642 | m = &ts->msg; |
643 | |
644 | spi_message_init(m); |
645 | |
646 | m->context = ts; |
647 | |
648 | ts->xfer[0].tx_buf = &ts->cmd_crtl1; |
649 | ts->xfer[0].len = 2; |
650 | ts->xfer[0].cs_change = 1; |
651 | |
652 | spi_message_add_tail(t: &ts->xfer[0], m); |
653 | |
654 | ts->xfer[1].tx_buf = &ts->cmd_dummy; /* Send ZERO */ |
655 | ts->xfer[1].len = 2; |
656 | ts->xfer[1].cs_change = 1; |
657 | |
658 | spi_message_add_tail(t: &ts->xfer[1], m); |
659 | |
660 | for (i = 0; i < AD7877_NR_SENSE; i++) { |
661 | ts->xfer[i + 2].rx_buf = &ts->conversion_data[AD7877_SEQ_YPOS + i]; |
662 | ts->xfer[i + 2].len = 2; |
663 | if (i < (AD7877_NR_SENSE - 1)) |
664 | ts->xfer[i + 2].cs_change = 1; |
665 | spi_message_add_tail(t: &ts->xfer[i + 2], m); |
666 | } |
667 | } |
668 | |
669 | static int ad7877_probe(struct spi_device *spi) |
670 | { |
671 | struct ad7877 *ts; |
672 | struct input_dev *input_dev; |
673 | struct ad7877_platform_data *pdata = dev_get_platdata(dev: &spi->dev); |
674 | int err; |
675 | u16 verify; |
676 | |
677 | if (!spi->irq) { |
678 | dev_dbg(&spi->dev, "no IRQ?\n" ); |
679 | return -ENODEV; |
680 | } |
681 | |
682 | if (!pdata) { |
683 | dev_dbg(&spi->dev, "no platform data?\n" ); |
684 | return -ENODEV; |
685 | } |
686 | |
687 | /* don't exceed max specified SPI CLK frequency */ |
688 | if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) { |
689 | dev_dbg(&spi->dev, "SPI CLK %d Hz?\n" ,spi->max_speed_hz); |
690 | return -EINVAL; |
691 | } |
692 | |
693 | spi->bits_per_word = 16; |
694 | err = spi_setup(spi); |
695 | if (err) { |
696 | dev_dbg(&spi->dev, "spi master doesn't support 16 bits/word\n" ); |
697 | return err; |
698 | } |
699 | |
700 | ts = devm_kzalloc(dev: &spi->dev, size: sizeof(struct ad7877), GFP_KERNEL); |
701 | if (!ts) |
702 | return -ENOMEM; |
703 | |
704 | input_dev = devm_input_allocate_device(&spi->dev); |
705 | if (!input_dev) |
706 | return -ENOMEM; |
707 | |
708 | err = devm_add_action_or_reset(&spi->dev, ad7877_disable, ts); |
709 | if (err) |
710 | return err; |
711 | |
712 | spi_set_drvdata(spi, data: ts); |
713 | ts->spi = spi; |
714 | ts->input = input_dev; |
715 | |
716 | timer_setup(&ts->timer, ad7877_timer, 0); |
717 | mutex_init(&ts->mutex); |
718 | spin_lock_init(&ts->lock); |
719 | |
720 | ts->model = pdata->model ? : 7877; |
721 | ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100; |
722 | ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; |
723 | ts->pressure_max = pdata->pressure_max ? : ~0; |
724 | |
725 | ts->stopacq_polarity = pdata->stopacq_polarity; |
726 | ts->first_conversion_delay = pdata->first_conversion_delay; |
727 | ts->acquisition_time = pdata->acquisition_time; |
728 | ts->averaging = pdata->averaging; |
729 | ts->pen_down_acc_interval = pdata->pen_down_acc_interval; |
730 | |
731 | snprintf(buf: ts->phys, size: sizeof(ts->phys), fmt: "%s/input0" , dev_name(dev: &spi->dev)); |
732 | |
733 | input_dev->name = "AD7877 Touchscreen" ; |
734 | input_dev->phys = ts->phys; |
735 | input_dev->dev.parent = &spi->dev; |
736 | |
737 | __set_bit(EV_KEY, input_dev->evbit); |
738 | __set_bit(BTN_TOUCH, input_dev->keybit); |
739 | __set_bit(EV_ABS, input_dev->evbit); |
740 | __set_bit(ABS_X, input_dev->absbit); |
741 | __set_bit(ABS_Y, input_dev->absbit); |
742 | __set_bit(ABS_PRESSURE, input_dev->absbit); |
743 | |
744 | input_set_abs_params(dev: input_dev, ABS_X, |
745 | min: pdata->x_min ? : 0, |
746 | max: pdata->x_max ? : MAX_12BIT, |
747 | fuzz: 0, flat: 0); |
748 | input_set_abs_params(dev: input_dev, ABS_Y, |
749 | min: pdata->y_min ? : 0, |
750 | max: pdata->y_max ? : MAX_12BIT, |
751 | fuzz: 0, flat: 0); |
752 | input_set_abs_params(dev: input_dev, ABS_PRESSURE, |
753 | min: pdata->pressure_min, max: pdata->pressure_max, fuzz: 0, flat: 0); |
754 | |
755 | ad7877_write(spi, AD7877_REG_SEQ1, AD7877_MM_SEQUENCE); |
756 | |
757 | verify = ad7877_read(spi, AD7877_REG_SEQ1); |
758 | |
759 | if (verify != AD7877_MM_SEQUENCE) { |
760 | dev_err(&spi->dev, "%s: Failed to probe %s\n" , |
761 | dev_name(&spi->dev), input_dev->name); |
762 | return -ENODEV; |
763 | } |
764 | |
765 | if (gpio3) |
766 | ad7877_write(spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_3_CONF); |
767 | |
768 | ad7877_setup_ts_def_msg(spi, ts); |
769 | |
770 | /* Request AD7877 /DAV GPIO interrupt */ |
771 | |
772 | err = devm_request_threaded_irq(dev: &spi->dev, irq: spi->irq, NULL, thread_fn: ad7877_irq, |
773 | IRQF_TRIGGER_FALLING | IRQF_ONESHOT, |
774 | devname: spi->dev.driver->name, dev_id: ts); |
775 | if (err) { |
776 | dev_dbg(&spi->dev, "irq %d busy?\n" , spi->irq); |
777 | return err; |
778 | } |
779 | |
780 | err = devm_device_add_group(dev: &spi->dev, grp: &ad7877_attr_group); |
781 | if (err) |
782 | return err; |
783 | |
784 | err = input_register_device(input_dev); |
785 | if (err) |
786 | return err; |
787 | |
788 | return 0; |
789 | } |
790 | |
791 | static int ad7877_suspend(struct device *dev) |
792 | { |
793 | struct ad7877 *ts = dev_get_drvdata(dev); |
794 | |
795 | ad7877_disable(data: ts); |
796 | |
797 | return 0; |
798 | } |
799 | |
800 | static int ad7877_resume(struct device *dev) |
801 | { |
802 | struct ad7877 *ts = dev_get_drvdata(dev); |
803 | |
804 | ad7877_enable(ts); |
805 | |
806 | return 0; |
807 | } |
808 | |
809 | static DEFINE_SIMPLE_DEV_PM_OPS(ad7877_pm, ad7877_suspend, ad7877_resume); |
810 | |
811 | static struct spi_driver ad7877_driver = { |
812 | .driver = { |
813 | .name = "ad7877" , |
814 | .pm = pm_sleep_ptr(&ad7877_pm), |
815 | }, |
816 | .probe = ad7877_probe, |
817 | }; |
818 | |
819 | module_spi_driver(ad7877_driver); |
820 | |
821 | MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>" ); |
822 | MODULE_DESCRIPTION("AD7877 touchscreen Driver" ); |
823 | MODULE_LICENSE("GPL" ); |
824 | MODULE_ALIAS("spi:ad7877" ); |
825 | |