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24#include <linux/device.h>
25#include <linux/init.h>
26#include <linux/delay.h>
27#include <linux/input.h>
28#include <linux/interrupt.h>
29#include <linux/irq.h>
30#include <linux/slab.h>
31#include <linux/spi/spi.h>
32#include <linux/i2c.h>
33#include <linux/gpio.h>
34
35#include <linux/spi/ad7879.h>
36#include "ad7879.h"
37
38#define AD7879_REG_ZEROS 0
39#define AD7879_REG_CTRL1 1
40#define AD7879_REG_CTRL2 2
41#define AD7879_REG_CTRL3 3
42#define AD7879_REG_AUX1HIGH 4
43#define AD7879_REG_AUX1LOW 5
44#define AD7879_REG_TEMP1HIGH 6
45#define AD7879_REG_TEMP1LOW 7
46#define AD7879_REG_XPLUS 8
47#define AD7879_REG_YPLUS 9
48#define AD7879_REG_Z1 10
49#define AD7879_REG_Z2 11
50#define AD7879_REG_AUXVBAT 12
51#define AD7879_REG_TEMP 13
52#define AD7879_REG_REVID 14
53
54
55#define AD7879_TMR(x) ((x & 0xFF) << 0)
56#define AD7879_ACQ(x) ((x & 0x3) << 8)
57#define AD7879_MODE_NOC (0 << 10)
58#define AD7879_MODE_SCC (1 << 10)
59#define AD7879_MODE_SEQ0 (2 << 10)
60#define AD7879_MODE_SEQ1 (3 << 10)
61#define AD7879_MODE_INT (1 << 15)
62
63
64#define AD7879_FCD(x) ((x & 0x3) << 0)
65#define AD7879_RESET (1 << 4)
66#define AD7879_MFS(x) ((x & 0x3) << 5)
67#define AD7879_AVG(x) ((x & 0x3) << 7)
68#define AD7879_SER (1 << 9)
69#define AD7879_DFR (0 << 9)
70#define AD7879_GPIOPOL (1 << 10)
71#define AD7879_GPIODIR (1 << 11)
72#define AD7879_GPIO_DATA (1 << 12)
73#define AD7879_GPIO_EN (1 << 13)
74#define AD7879_PM(x) ((x & 0x3) << 14)
75#define AD7879_PM_SHUTDOWN (0)
76#define AD7879_PM_DYN (1)
77#define AD7879_PM_FULLON (2)
78
79
80#define AD7879_TEMPMASK_BIT (1<<15)
81#define AD7879_AUXVBATMASK_BIT (1<<14)
82#define AD7879_INTMODE_BIT (1<<13)
83#define AD7879_GPIOALERTMASK_BIT (1<<12)
84#define AD7879_AUXLOW_BIT (1<<11)
85#define AD7879_AUXHIGH_BIT (1<<10)
86#define AD7879_TEMPLOW_BIT (1<<9)
87#define AD7879_TEMPHIGH_BIT (1<<8)
88#define AD7879_YPLUS_BIT (1<<7)
89#define AD7879_XPLUS_BIT (1<<6)
90#define AD7879_Z1_BIT (1<<5)
91#define AD7879_Z2_BIT (1<<4)
92#define AD7879_AUX_BIT (1<<3)
93#define AD7879_VBAT_BIT (1<<2)
94#define AD7879_TEMP_BIT (1<<1)
95
96enum {
97 AD7879_SEQ_XPOS = 0,
98 AD7879_SEQ_YPOS = 1,
99 AD7879_SEQ_Z1 = 2,
100 AD7879_SEQ_Z2 = 3,
101 AD7879_NR_SENSE = 4,
102};
103
104#define MAX_12BIT ((1<<12)-1)
105#define TS_PEN_UP_TIMEOUT msecs_to_jiffies(50)
106
107struct ad7879 {
108 const struct ad7879_bus_ops *bops;
109
110 struct device *dev;
111 struct input_dev *input;
112 struct timer_list timer;
113#ifdef CONFIG_GPIOLIB
114 struct gpio_chip gc;
115 struct mutex mutex;
116#endif
117 unsigned int irq;
118 bool disabled;
119 bool suspended;
120 u16 conversion_data[AD7879_NR_SENSE];
121 char phys[32];
122 u8 first_conversion_delay;
123 u8 acquisition_time;
124 u8 averaging;
125 u8 pen_down_acc_interval;
126 u8 median;
127 u16 x_plate_ohms;
128 u16 pressure_max;
129 u16 cmd_crtl1;
130 u16 cmd_crtl2;
131 u16 cmd_crtl3;
132 int x;
133 int y;
134 int Rt;
135};
136
137static int ad7879_read(struct ad7879 *ts, u8 reg)
138{
139 return ts->bops->read(ts->dev, reg);
140}
141
142static int ad7879_multi_read(struct ad7879 *ts, u8 first_reg, u8 count, u16 *buf)
143{
144 return ts->bops->multi_read(ts->dev, first_reg, count, buf);
145}
146
147static int ad7879_write(struct ad7879 *ts, u8 reg, u16 val)
148{
149 return ts->bops->write(ts->dev, reg, val);
150}
151
152static int ad7879_report(struct ad7879 *ts)
153{
154 struct input_dev *input_dev = ts->input;
155 unsigned Rt;
156 u16 x, y, z1, z2;
157
158 x = ts->conversion_data[AD7879_SEQ_XPOS] & MAX_12BIT;
159 y = ts->conversion_data[AD7879_SEQ_YPOS] & MAX_12BIT;
160 z1 = ts->conversion_data[AD7879_SEQ_Z1] & MAX_12BIT;
161 z2 = ts->conversion_data[AD7879_SEQ_Z2] & MAX_12BIT;
162
163
164
165
166
167
168
169
170
171
172
173
174
175 if (likely(x && z1)) {
176
177 Rt = (z2 - z1) * x * ts->x_plate_ohms;
178 Rt /= z1;
179 Rt = (Rt + 2047) >> 12;
180
181
182
183
184
185 if (Rt > ts->pressure_max)
186 return -EINVAL;
187
188
189
190
191
192
193
194 if (timer_pending(&ts->timer)) {
195
196 input_report_key(input_dev, BTN_TOUCH, 1);
197 input_report_abs(input_dev, ABS_X, ts->x);
198 input_report_abs(input_dev, ABS_Y, ts->y);
199 input_report_abs(input_dev, ABS_PRESSURE, ts->Rt);
200 input_sync(input_dev);
201 }
202
203 ts->x = x;
204 ts->y = y;
205 ts->Rt = Rt;
206
207 return 0;
208 }
209
210 return -EINVAL;
211}
212
213static void ad7879_ts_event_release(struct ad7879 *ts)
214{
215 struct input_dev *input_dev = ts->input;
216
217 input_report_abs(input_dev, ABS_PRESSURE, 0);
218 input_report_key(input_dev, BTN_TOUCH, 0);
219 input_sync(input_dev);
220}
221
222static void ad7879_timer(unsigned long handle)
223{
224 struct ad7879 *ts = (void *)handle;
225
226 ad7879_ts_event_release(ts);
227}
228
229static irqreturn_t ad7879_irq(int irq, void *handle)
230{
231 struct ad7879 *ts = handle;
232
233 ad7879_multi_read(ts, AD7879_REG_XPLUS, AD7879_NR_SENSE, ts->conversion_data);
234
235 if (!ad7879_report(ts))
236 mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT);
237
238 return IRQ_HANDLED;
239}
240
241static void __ad7879_enable(struct ad7879 *ts)
242{
243 ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
244 ad7879_write(ts, AD7879_REG_CTRL3, ts->cmd_crtl3);
245 ad7879_write(ts, AD7879_REG_CTRL1, ts->cmd_crtl1);
246
247 enable_irq(ts->irq);
248}
249
250static void __ad7879_disable(struct ad7879 *ts)
251{
252 disable_irq(ts->irq);
253
254 if (del_timer_sync(&ts->timer))
255 ad7879_ts_event_release(ts);
256
257 ad7879_write(ts, AD7879_REG_CTRL2, AD7879_PM(AD7879_PM_SHUTDOWN));
258}
259
260
261static int ad7879_open(struct input_dev *input)
262{
263 struct ad7879 *ts = input_get_drvdata(input);
264
265
266 if (!ts->disabled && !ts->suspended)
267 __ad7879_enable(ts);
268
269 return 0;
270}
271
272static void ad7879_close(struct input_dev* input)
273{
274 struct ad7879 *ts = input_get_drvdata(input);
275
276
277 if (!ts->disabled && !ts->suspended)
278 __ad7879_disable(ts);
279}
280
281void ad7879_suspend(struct ad7879 *ts)
282{
283 mutex_lock(&ts->input->mutex);
284
285 if (!ts->suspended && !ts->disabled && ts->input->users)
286 __ad7879_disable(ts);
287
288 ts->suspended = true;
289
290 mutex_unlock(&ts->input->mutex);
291}
292EXPORT_SYMBOL(ad7879_suspend);
293
294void ad7879_resume(struct ad7879 *ts)
295{
296 mutex_lock(&ts->input->mutex);
297
298 if (ts->suspended && !ts->disabled && ts->input->users)
299 __ad7879_enable(ts);
300
301 ts->suspended = false;
302
303 mutex_unlock(&ts->input->mutex);
304}
305EXPORT_SYMBOL(ad7879_resume);
306
307static void ad7879_toggle(struct ad7879 *ts, bool disable)
308{
309 mutex_lock(&ts->input->mutex);
310
311 if (!ts->suspended && ts->input->users != 0) {
312
313 if (disable) {
314 if (ts->disabled)
315 __ad7879_enable(ts);
316 } else {
317 if (!ts->disabled)
318 __ad7879_disable(ts);
319 }
320 }
321
322 ts->disabled = disable;
323
324 mutex_unlock(&ts->input->mutex);
325}
326
327static ssize_t ad7879_disable_show(struct device *dev,
328 struct device_attribute *attr, char *buf)
329{
330 struct ad7879 *ts = dev_get_drvdata(dev);
331
332 return sprintf(buf, "%u\n", ts->disabled);
333}
334
335static ssize_t ad7879_disable_store(struct device *dev,
336 struct device_attribute *attr,
337 const char *buf, size_t count)
338{
339 struct ad7879 *ts = dev_get_drvdata(dev);
340 unsigned long val;
341 int error;
342
343 error = strict_strtoul(buf, 10, &val);
344 if (error)
345 return error;
346
347 ad7879_toggle(ts, val);
348
349 return count;
350}
351
352static DEVICE_ATTR(disable, 0664, ad7879_disable_show, ad7879_disable_store);
353
354static struct attribute *ad7879_attributes[] = {
355 &dev_attr_disable.attr,
356 NULL
357};
358
359static const struct attribute_group ad7879_attr_group = {
360 .attrs = ad7879_attributes,
361};
362
363#ifdef CONFIG_GPIOLIB
364static int ad7879_gpio_direction_input(struct gpio_chip *chip,
365 unsigned gpio)
366{
367 struct ad7879 *ts = container_of(chip, struct ad7879, gc);
368 int err;
369
370 mutex_lock(&ts->mutex);
371 ts->cmd_crtl2 |= AD7879_GPIO_EN | AD7879_GPIODIR | AD7879_GPIOPOL;
372 err = ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
373 mutex_unlock(&ts->mutex);
374
375 return err;
376}
377
378static int ad7879_gpio_direction_output(struct gpio_chip *chip,
379 unsigned gpio, int level)
380{
381 struct ad7879 *ts = container_of(chip, struct ad7879, gc);
382 int err;
383
384 mutex_lock(&ts->mutex);
385 ts->cmd_crtl2 &= ~AD7879_GPIODIR;
386 ts->cmd_crtl2 |= AD7879_GPIO_EN | AD7879_GPIOPOL;
387 if (level)
388 ts->cmd_crtl2 |= AD7879_GPIO_DATA;
389 else
390 ts->cmd_crtl2 &= ~AD7879_GPIO_DATA;
391
392 err = ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
393 mutex_unlock(&ts->mutex);
394
395 return err;
396}
397
398static int ad7879_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
399{
400 struct ad7879 *ts = container_of(chip, struct ad7879, gc);
401 u16 val;
402
403 mutex_lock(&ts->mutex);
404 val = ad7879_read(ts, AD7879_REG_CTRL2);
405 mutex_unlock(&ts->mutex);
406
407 return !!(val & AD7879_GPIO_DATA);
408}
409
410static void ad7879_gpio_set_value(struct gpio_chip *chip,
411 unsigned gpio, int value)
412{
413 struct ad7879 *ts = container_of(chip, struct ad7879, gc);
414
415 mutex_lock(&ts->mutex);
416 if (value)
417 ts->cmd_crtl2 |= AD7879_GPIO_DATA;
418 else
419 ts->cmd_crtl2 &= ~AD7879_GPIO_DATA;
420
421 ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
422 mutex_unlock(&ts->mutex);
423}
424
425static int ad7879_gpio_add(struct ad7879 *ts,
426 const struct ad7879_platform_data *pdata)
427{
428 int ret = 0;
429
430 mutex_init(&ts->mutex);
431
432 if (pdata->gpio_export) {
433 ts->gc.direction_input = ad7879_gpio_direction_input;
434 ts->gc.direction_output = ad7879_gpio_direction_output;
435 ts->gc.get = ad7879_gpio_get_value;
436 ts->gc.set = ad7879_gpio_set_value;
437 ts->gc.can_sleep = 1;
438 ts->gc.base = pdata->gpio_base;
439 ts->gc.ngpio = 1;
440 ts->gc.label = "AD7879-GPIO";
441 ts->gc.owner = THIS_MODULE;
442 ts->gc.dev = ts->dev;
443
444 ret = gpiochip_add(&ts->gc);
445 if (ret)
446 dev_err(ts->dev, "failed to register gpio %d\n",
447 ts->gc.base);
448 }
449
450 return ret;
451}
452
453static void ad7879_gpio_remove(struct ad7879 *ts)
454{
455 const struct ad7879_platform_data *pdata = ts->dev->platform_data;
456 int ret;
457
458 if (pdata->gpio_export) {
459 ret = gpiochip_remove(&ts->gc);
460 if (ret)
461 dev_err(ts->dev, "failed to remove gpio %d\n",
462 ts->gc.base);
463 }
464}
465#else
466static inline int ad7879_gpio_add(struct ad7879 *ts,
467 const struct ad7879_platform_data *pdata)
468{
469 return 0;
470}
471
472static inline void ad7879_gpio_remove(struct ad7879 *ts)
473{
474}
475#endif
476
477struct ad7879 *ad7879_probe(struct device *dev, u8 devid, unsigned int irq,
478 const struct ad7879_bus_ops *bops)
479{
480 struct ad7879_platform_data *pdata = dev->platform_data;
481 struct ad7879 *ts;
482 struct input_dev *input_dev;
483 int err;
484 u16 revid;
485
486 if (!irq) {
487 dev_err(dev, "no IRQ?\n");
488 err = -EINVAL;
489 goto err_out;
490 }
491
492 if (!pdata) {
493 dev_err(dev, "no platform data?\n");
494 err = -EINVAL;
495 goto err_out;
496 }
497
498 ts = kzalloc(sizeof(*ts), GFP_KERNEL);
499 input_dev = input_allocate_device();
500 if (!ts || !input_dev) {
501 err = -ENOMEM;
502 goto err_free_mem;
503 }
504
505 ts->bops = bops;
506 ts->dev = dev;
507 ts->input = input_dev;
508 ts->irq = irq;
509
510 setup_timer(&ts->timer, ad7879_timer, (unsigned long) ts);
511
512 ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
513 ts->pressure_max = pdata->pressure_max ? : ~0;
514
515 ts->first_conversion_delay = pdata->first_conversion_delay;
516 ts->acquisition_time = pdata->acquisition_time;
517 ts->averaging = pdata->averaging;
518 ts->pen_down_acc_interval = pdata->pen_down_acc_interval;
519 ts->median = pdata->median;
520
521 snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(dev));
522
523 input_dev->name = "AD7879 Touchscreen";
524 input_dev->phys = ts->phys;
525 input_dev->dev.parent = dev;
526 input_dev->id.bustype = bops->bustype;
527
528 input_dev->open = ad7879_open;
529 input_dev->close = ad7879_close;
530
531 input_set_drvdata(input_dev, ts);
532
533 __set_bit(EV_ABS, input_dev->evbit);
534 __set_bit(ABS_X, input_dev->absbit);
535 __set_bit(ABS_Y, input_dev->absbit);
536 __set_bit(ABS_PRESSURE, input_dev->absbit);
537
538 __set_bit(EV_KEY, input_dev->evbit);
539 __set_bit(BTN_TOUCH, input_dev->keybit);
540
541 input_set_abs_params(input_dev, ABS_X,
542 pdata->x_min ? : 0,
543 pdata->x_max ? : MAX_12BIT,
544 0, 0);
545 input_set_abs_params(input_dev, ABS_Y,
546 pdata->y_min ? : 0,
547 pdata->y_max ? : MAX_12BIT,
548 0, 0);
549 input_set_abs_params(input_dev, ABS_PRESSURE,
550 pdata->pressure_min, pdata->pressure_max, 0, 0);
551
552 err = ad7879_write(ts, AD7879_REG_CTRL2, AD7879_RESET);
553 if (err < 0) {
554 dev_err(dev, "Failed to write %s\n", input_dev->name);
555 goto err_free_mem;
556 }
557
558 revid = ad7879_read(ts, AD7879_REG_REVID);
559 input_dev->id.product = (revid & 0xff);
560 input_dev->id.version = revid >> 8;
561 if (input_dev->id.product != devid) {
562 dev_err(dev, "Failed to probe %s (%x vs %x)\n",
563 input_dev->name, devid, revid);
564 err = -ENODEV;
565 goto err_free_mem;
566 }
567
568 ts->cmd_crtl3 = AD7879_YPLUS_BIT |
569 AD7879_XPLUS_BIT |
570 AD7879_Z2_BIT |
571 AD7879_Z1_BIT |
572 AD7879_TEMPMASK_BIT |
573 AD7879_AUXVBATMASK_BIT |
574 AD7879_GPIOALERTMASK_BIT;
575
576 ts->cmd_crtl2 = AD7879_PM(AD7879_PM_DYN) | AD7879_DFR |
577 AD7879_AVG(ts->averaging) |
578 AD7879_MFS(ts->median) |
579 AD7879_FCD(ts->first_conversion_delay);
580
581 ts->cmd_crtl1 = AD7879_MODE_INT | AD7879_MODE_SEQ1 |
582 AD7879_ACQ(ts->acquisition_time) |
583 AD7879_TMR(ts->pen_down_acc_interval);
584
585 err = request_threaded_irq(ts->irq, NULL, ad7879_irq,
586 IRQF_TRIGGER_FALLING,
587 dev_name(dev), ts);
588 if (err) {
589 dev_err(dev, "irq %d busy?\n", ts->irq);
590 goto err_free_mem;
591 }
592
593 __ad7879_disable(ts);
594
595 err = sysfs_create_group(&dev->kobj, &ad7879_attr_group);
596 if (err)
597 goto err_free_irq;
598
599 err = ad7879_gpio_add(ts, pdata);
600 if (err)
601 goto err_remove_attr;
602
603 err = input_register_device(input_dev);
604 if (err)
605 goto err_remove_gpio;
606
607 return ts;
608
609err_remove_gpio:
610 ad7879_gpio_remove(ts);
611err_remove_attr:
612 sysfs_remove_group(&dev->kobj, &ad7879_attr_group);
613err_free_irq:
614 free_irq(ts->irq, ts);
615err_free_mem:
616 input_free_device(input_dev);
617 kfree(ts);
618err_out:
619 return ERR_PTR(err);
620}
621EXPORT_SYMBOL(ad7879_probe);
622
623void ad7879_remove(struct ad7879 *ts)
624{
625 ad7879_gpio_remove(ts);
626 sysfs_remove_group(&ts->dev->kobj, &ad7879_attr_group);
627 free_irq(ts->irq, ts);
628 input_unregister_device(ts->input);
629 kfree(ts);
630}
631EXPORT_SYMBOL(ad7879_remove);
632
633MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
634MODULE_DESCRIPTION("AD7879(-1) touchscreen Driver");
635MODULE_LICENSE("GPL");
636
