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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Touchscreen driver for UCB1x00-based touchscreens
4 *
5 * Copyright (C) 2001 Russell King, All Rights Reserved.
6 * Copyright (C) 2005 Pavel Machek
7 *
8 * 21-Jan-2002 <jco@ict.es> :
9 *
10 * Added support for synchronous A/D mode. This mode is useful to
11 * avoid noise induced in the touchpanel by the LCD, provided that
12 * the UCB1x00 has a valid LCD sync signal routed to its ADCSYNC pin.
13 * It is important to note that the signal connected to the ADCSYNC
14 * pin should provide pulses even when the LCD is blanked, otherwise
15 * a pen touch needed to unblank the LCD will never be read.
16 */
17#include <linux/module.h>
18#include <linux/moduleparam.h>
19#include <linux/init.h>
20#include <linux/interrupt.h>
21#include <linux/sched.h>
22#include <linux/spinlock.h>
23#include <linux/completion.h>
24#include <linux/delay.h>
25#include <linux/string.h>
26#include <linux/input.h>
27#include <linux/device.h>
28#include <linux/freezer.h>
29#include <linux/slab.h>
30#include <linux/kthread.h>
31#include <linux/mfd/ucb1x00.h>
32
33#include <mach/collie.h>
34#include <asm/mach-types.h>
35
36
37
38struct ucb1x00_ts {
39 struct input_dev *idev;
40 struct ucb1x00 *ucb;
41
42 spinlock_t irq_lock;
43 unsigned irq_disabled;
44 wait_queue_head_t irq_wait;
45 struct task_struct *rtask;
46 u16 x_res;
47 u16 y_res;
48
49 unsigned int adcsync:1;
50};
51
52static int adcsync;
53
54static inline void ucb1x00_ts_evt_add(struct ucb1x00_ts *ts, u16 pressure, u16 x, u16 y)
55{
56 struct input_dev *idev = ts->idev;
57
58 input_report_abs(idev, ABS_X, x);
59 input_report_abs(idev, ABS_Y, y);
60 input_report_abs(idev, ABS_PRESSURE, pressure);
61 input_report_key(idev, BTN_TOUCH, 1);
62 input_sync(idev);
63}
64
65static inline void ucb1x00_ts_event_release(struct ucb1x00_ts *ts)
66{
67 struct input_dev *idev = ts->idev;
68
69 input_report_abs(idev, ABS_PRESSURE, 0);
70 input_report_key(idev, BTN_TOUCH, 0);
71 input_sync(idev);
72}
73
74/*
75 * Switch to interrupt mode.
76 */
77static inline void ucb1x00_ts_mode_int(struct ucb1x00_ts *ts)
78{
79 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
80 UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
81 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
82 UCB_TS_CR_MODE_INT);
83}
84
85/*
86 * Switch to pressure mode, and read pressure. We don't need to wait
87 * here, since both plates are being driven.
88 */
89static inline unsigned int ucb1x00_ts_read_pressure(struct ucb1x00_ts *ts)
90{
91 if (machine_is_collie()) {
92 ucb1x00_io_write(ts->ucb, COLLIE_TC35143_GPIO_TBL_CHK, 0);
93 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
94 UCB_TS_CR_TSPX_POW | UCB_TS_CR_TSMX_POW |
95 UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
96
97 udelay(55);
98
99 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_AD2, ts->adcsync);
100 } else {
101 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
102 UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
103 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
104 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
105
106 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
107 }
108}
109
110/*
111 * Switch to X position mode and measure Y plate. We switch the plate
112 * configuration in pressure mode, then switch to position mode. This
113 * gives a faster response time. Even so, we need to wait about 55us
114 * for things to stabilise.
115 */
116static inline unsigned int ucb1x00_ts_read_xpos(struct ucb1x00_ts *ts)
117{
118 if (machine_is_collie())
119 ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
120 else {
121 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
122 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
123 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
124 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
125 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
126 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
127 }
128 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
129 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
130 UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
131
132 udelay(55);
133
134 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
135}
136
137/*
138 * Switch to Y position mode and measure X plate. We switch the plate
139 * configuration in pressure mode, then switch to position mode. This
140 * gives a faster response time. Even so, we need to wait about 55us
141 * for things to stabilise.
142 */
143static inline unsigned int ucb1x00_ts_read_ypos(struct ucb1x00_ts *ts)
144{
145 if (machine_is_collie())
146 ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
147 else {
148 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
149 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
150 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
151 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
152 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
153 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
154 }
155
156 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
157 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
158 UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
159
160 udelay(55);
161
162 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPX, ts->adcsync);
163}
164
165/*
166 * Switch to X plate resistance mode. Set MX to ground, PX to
167 * supply. Measure current.
168 */
169static inline unsigned int ucb1x00_ts_read_xres(struct ucb1x00_ts *ts)
170{
171 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
172 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
173 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
174 return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
175}
176
177/*
178 * Switch to Y plate resistance mode. Set MY to ground, PY to
179 * supply. Measure current.
180 */
181static inline unsigned int ucb1x00_ts_read_yres(struct ucb1x00_ts *ts)
182{
183 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
184 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
185 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
186 return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
187}
188
189static inline int ucb1x00_ts_pen_down(struct ucb1x00_ts *ts)
190{
191 unsigned int val = ucb1x00_reg_read(ts->ucb, UCB_TS_CR);
192
193 if (machine_is_collie())
194 return (!(val & (UCB_TS_CR_TSPX_LOW)));
195 else
196 return (val & (UCB_TS_CR_TSPX_LOW | UCB_TS_CR_TSMX_LOW));
197}
198
199/*
200 * This is a RT kernel thread that handles the ADC accesses
201 * (mainly so we can use semaphores in the UCB1200 core code
202 * to serialise accesses to the ADC).
203 */
204static int ucb1x00_thread(void *_ts)
205{
206 struct ucb1x00_ts *ts = _ts;
207 DECLARE_WAITQUEUE(wait, current);
208 bool frozen, ignore = false;
209 int valid = 0;
210
211 set_freezable();
212 add_wait_queue(&ts->irq_wait, &wait);
213 while (!kthread_freezable_should_stop(&frozen)) {
214 unsigned int x, y, p;
215 signed long timeout;
216
217 if (frozen)
218 ignore = true;
219
220 ucb1x00_adc_enable(ts->ucb);
221
222 x = ucb1x00_ts_read_xpos(ts);
223 y = ucb1x00_ts_read_ypos(ts);
224 p = ucb1x00_ts_read_pressure(ts);
225
226 /*
227 * Switch back to interrupt mode.
228 */
229 ucb1x00_ts_mode_int(ts);
230 ucb1x00_adc_disable(ts->ucb);
231
232 msleep(10);
233
234 ucb1x00_enable(ts->ucb);
235
236
237 if (ucb1x00_ts_pen_down(ts)) {
238 set_current_state(TASK_INTERRUPTIBLE);
239
240 spin_lock_irq(&ts->irq_lock);
241 if (ts->irq_disabled) {
242 ts->irq_disabled = 0;
243 enable_irq(ts->ucb->irq_base + UCB_IRQ_TSPX);
244 }
245 spin_unlock_irq(&ts->irq_lock);
246 ucb1x00_disable(ts->ucb);
247
248 /*
249 * If we spat out a valid sample set last time,
250 * spit out a "pen off" sample here.
251 */
252 if (valid) {
253 ucb1x00_ts_event_release(ts);
254 valid = 0;
255 }
256
257 timeout = MAX_SCHEDULE_TIMEOUT;
258 } else {
259 ucb1x00_disable(ts->ucb);
260
261 /*
262 * Filtering is policy. Policy belongs in user
263 * space. We therefore leave it to user space
264 * to do any filtering they please.
265 */
266 if (!ignore) {
267 ucb1x00_ts_evt_add(ts, p, x, y);
268 valid = 1;
269 }
270
271 set_current_state(TASK_INTERRUPTIBLE);
272 timeout = HZ / 100;
273 }
274
275 schedule_timeout(timeout);
276 }
277
278 remove_wait_queue(&ts->irq_wait, &wait);
279
280 ts->rtask = NULL;
281 return 0;
282}
283
284/*
285 * We only detect touch screen _touches_ with this interrupt
286 * handler, and even then we just schedule our task.
287 */
288static irqreturn_t ucb1x00_ts_irq(int irq, void *id)
289{
290 struct ucb1x00_ts *ts = id;
291
292 spin_lock(&ts->irq_lock);
293 ts->irq_disabled = 1;
294 disable_irq_nosync(ts->ucb->irq_base + UCB_IRQ_TSPX);
295 spin_unlock(&ts->irq_lock);
296 wake_up(&ts->irq_wait);
297
298 return IRQ_HANDLED;
299}
300
301static int ucb1x00_ts_open(struct input_dev *idev)
302{
303 struct ucb1x00_ts *ts = input_get_drvdata(idev);
304 unsigned long flags = 0;
305 int ret = 0;
306
307 BUG_ON(ts->rtask);
308
309 if (machine_is_collie())
310 flags = IRQF_TRIGGER_RISING;
311 else
312 flags = IRQF_TRIGGER_FALLING;
313
314 ts->irq_disabled = 0;
315
316 init_waitqueue_head(&ts->irq_wait);
317 ret = request_irq(ts->ucb->irq_base + UCB_IRQ_TSPX, ucb1x00_ts_irq,
318 flags, "ucb1x00-ts", ts);
319 if (ret < 0)
320 goto out;
321
322 /*
323 * If we do this at all, we should allow the user to
324 * measure and read the X and Y resistance at any time.
325 */
326 ucb1x00_adc_enable(ts->ucb);
327 ts->x_res = ucb1x00_ts_read_xres(ts);
328 ts->y_res = ucb1x00_ts_read_yres(ts);
329 ucb1x00_adc_disable(ts->ucb);
330
331 ts->rtask = kthread_run(ucb1x00_thread, ts, "ktsd");
332 if (!IS_ERR(ts->rtask)) {
333 ret = 0;
334 } else {
335 free_irq(ts->ucb->irq_base + UCB_IRQ_TSPX, ts);
336 ts->rtask = NULL;
337 ret = -EFAULT;
338 }
339
340 out:
341 return ret;
342}
343
344/*
345 * Release touchscreen resources. Disable IRQs.
346 */
347static void ucb1x00_ts_close(struct input_dev *idev)
348{
349 struct ucb1x00_ts *ts = input_get_drvdata(idev);
350
351 if (ts->rtask)
352 kthread_stop(ts->rtask);
353
354 ucb1x00_enable(ts->ucb);
355 free_irq(ts->ucb->irq_base + UCB_IRQ_TSPX, ts);
356 ucb1x00_reg_write(ts->ucb, UCB_TS_CR, 0);
357 ucb1x00_disable(ts->ucb);
358}
359
360
361/*
362 * Initialisation.
363 */
364static int ucb1x00_ts_add(struct ucb1x00_dev *dev)
365{
366 struct ucb1x00_ts *ts;
367 struct input_dev *idev;
368 int err;
369
370 ts = kzalloc(sizeof(struct ucb1x00_ts), GFP_KERNEL);
371 idev = input_allocate_device();
372 if (!ts || !idev) {
373 err = -ENOMEM;
374 goto fail;
375 }
376
377 ts->ucb = dev->ucb;
378 ts->idev = idev;
379 ts->adcsync = adcsync ? UCB_SYNC : UCB_NOSYNC;
380 spin_lock_init(&ts->irq_lock);
381
382 idev->name = "Touchscreen panel";
383 idev->id.product = ts->ucb->id;
384 idev->open = ucb1x00_ts_open;
385 idev->close = ucb1x00_ts_close;
386 idev->dev.parent = &ts->ucb->dev;
387
388 idev->evbit[0] = BIT_MASK(EV_ABS) | BIT_MASK(EV_KEY);
389 idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
390
391 input_set_drvdata(idev, ts);
392
393 ucb1x00_adc_enable(ts->ucb);
394 ts->x_res = ucb1x00_ts_read_xres(ts);
395 ts->y_res = ucb1x00_ts_read_yres(ts);
396 ucb1x00_adc_disable(ts->ucb);
397
398 input_set_abs_params(idev, ABS_X, 0, ts->x_res, 0, 0);
399 input_set_abs_params(idev, ABS_Y, 0, ts->y_res, 0, 0);
400 input_set_abs_params(idev, ABS_PRESSURE, 0, 0, 0, 0);
401
402 err = input_register_device(idev);
403 if (err)
404 goto fail;
405
406 dev->priv = ts;
407
408 return 0;
409
410 fail:
411 input_free_device(idev);
412 kfree(ts);
413 return err;
414}
415
416static void ucb1x00_ts_remove(struct ucb1x00_dev *dev)
417{
418 struct ucb1x00_ts *ts = dev->priv;
419
420 input_unregister_device(ts->idev);
421 kfree(ts);
422}
423
424static struct ucb1x00_driver ucb1x00_ts_driver = {
425 .add = ucb1x00_ts_add,
426 .remove = ucb1x00_ts_remove,
427};
428
429static int __init ucb1x00_ts_init(void)
430{
431 return ucb1x00_register_driver(&ucb1x00_ts_driver);
432}
433
434static void __exit ucb1x00_ts_exit(void)
435{
436 ucb1x00_unregister_driver(&ucb1x00_ts_driver);
437}
438
439module_param(adcsync, int, 0444);
440module_init(ucb1x00_ts_init);
441module_exit(ucb1x00_ts_exit);
442
443MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
444MODULE_DESCRIPTION("UCB1x00 touchscreen driver");
445MODULE_LICENSE("GPL");
1/*
2 * Touchscreen driver for UCB1x00-based touchscreens
3 *
4 * Copyright (C) 2001 Russell King, All Rights Reserved.
5 * Copyright (C) 2005 Pavel Machek
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 * 21-Jan-2002 <jco@ict.es> :
12 *
13 * Added support for synchronous A/D mode. This mode is useful to
14 * avoid noise induced in the touchpanel by the LCD, provided that
15 * the UCB1x00 has a valid LCD sync signal routed to its ADCSYNC pin.
16 * It is important to note that the signal connected to the ADCSYNC
17 * pin should provide pulses even when the LCD is blanked, otherwise
18 * a pen touch needed to unblank the LCD will never be read.
19 */
20#include <linux/module.h>
21#include <linux/moduleparam.h>
22#include <linux/init.h>
23#include <linux/interrupt.h>
24#include <linux/sched.h>
25#include <linux/spinlock.h>
26#include <linux/completion.h>
27#include <linux/delay.h>
28#include <linux/string.h>
29#include <linux/input.h>
30#include <linux/device.h>
31#include <linux/freezer.h>
32#include <linux/slab.h>
33#include <linux/kthread.h>
34#include <linux/mfd/ucb1x00.h>
35
36#include <mach/collie.h>
37#include <asm/mach-types.h>
38
39
40
41struct ucb1x00_ts {
42 struct input_dev *idev;
43 struct ucb1x00 *ucb;
44
45 spinlock_t irq_lock;
46 unsigned irq_disabled;
47 wait_queue_head_t irq_wait;
48 struct task_struct *rtask;
49 u16 x_res;
50 u16 y_res;
51
52 unsigned int adcsync:1;
53};
54
55static int adcsync;
56
57static inline void ucb1x00_ts_evt_add(struct ucb1x00_ts *ts, u16 pressure, u16 x, u16 y)
58{
59 struct input_dev *idev = ts->idev;
60
61 input_report_abs(idev, ABS_X, x);
62 input_report_abs(idev, ABS_Y, y);
63 input_report_abs(idev, ABS_PRESSURE, pressure);
64 input_report_key(idev, BTN_TOUCH, 1);
65 input_sync(idev);
66}
67
68static inline void ucb1x00_ts_event_release(struct ucb1x00_ts *ts)
69{
70 struct input_dev *idev = ts->idev;
71
72 input_report_abs(idev, ABS_PRESSURE, 0);
73 input_report_key(idev, BTN_TOUCH, 0);
74 input_sync(idev);
75}
76
77/*
78 * Switch to interrupt mode.
79 */
80static inline void ucb1x00_ts_mode_int(struct ucb1x00_ts *ts)
81{
82 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
83 UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
84 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
85 UCB_TS_CR_MODE_INT);
86}
87
88/*
89 * Switch to pressure mode, and read pressure. We don't need to wait
90 * here, since both plates are being driven.
91 */
92static inline unsigned int ucb1x00_ts_read_pressure(struct ucb1x00_ts *ts)
93{
94 if (machine_is_collie()) {
95 ucb1x00_io_write(ts->ucb, COLLIE_TC35143_GPIO_TBL_CHK, 0);
96 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
97 UCB_TS_CR_TSPX_POW | UCB_TS_CR_TSMX_POW |
98 UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
99
100 udelay(55);
101
102 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_AD2, ts->adcsync);
103 } else {
104 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
105 UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
106 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
107 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
108
109 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
110 }
111}
112
113/*
114 * Switch to X position mode and measure Y plate. We switch the plate
115 * configuration in pressure mode, then switch to position mode. This
116 * gives a faster response time. Even so, we need to wait about 55us
117 * for things to stabilise.
118 */
119static inline unsigned int ucb1x00_ts_read_xpos(struct ucb1x00_ts *ts)
120{
121 if (machine_is_collie())
122 ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
123 else {
124 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
125 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
126 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
127 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
128 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
129 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
130 }
131 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
132 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
133 UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
134
135 udelay(55);
136
137 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
138}
139
140/*
141 * Switch to Y position mode and measure X plate. We switch the plate
142 * configuration in pressure mode, then switch to position mode. This
143 * gives a faster response time. Even so, we need to wait about 55us
144 * for things to stabilise.
145 */
146static inline unsigned int ucb1x00_ts_read_ypos(struct ucb1x00_ts *ts)
147{
148 if (machine_is_collie())
149 ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
150 else {
151 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
152 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
153 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
154 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
155 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
156 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
157 }
158
159 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
160 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
161 UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
162
163 udelay(55);
164
165 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPX, ts->adcsync);
166}
167
168/*
169 * Switch to X plate resistance mode. Set MX to ground, PX to
170 * supply. Measure current.
171 */
172static inline unsigned int ucb1x00_ts_read_xres(struct ucb1x00_ts *ts)
173{
174 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
175 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
176 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
177 return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
178}
179
180/*
181 * Switch to Y plate resistance mode. Set MY to ground, PY to
182 * supply. Measure current.
183 */
184static inline unsigned int ucb1x00_ts_read_yres(struct ucb1x00_ts *ts)
185{
186 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
187 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
188 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
189 return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
190}
191
192static inline int ucb1x00_ts_pen_down(struct ucb1x00_ts *ts)
193{
194 unsigned int val = ucb1x00_reg_read(ts->ucb, UCB_TS_CR);
195
196 if (machine_is_collie())
197 return (!(val & (UCB_TS_CR_TSPX_LOW)));
198 else
199 return (val & (UCB_TS_CR_TSPX_LOW | UCB_TS_CR_TSMX_LOW));
200}
201
202/*
203 * This is a RT kernel thread that handles the ADC accesses
204 * (mainly so we can use semaphores in the UCB1200 core code
205 * to serialise accesses to the ADC).
206 */
207static int ucb1x00_thread(void *_ts)
208{
209 struct ucb1x00_ts *ts = _ts;
210 DECLARE_WAITQUEUE(wait, current);
211 bool frozen, ignore = false;
212 int valid = 0;
213
214 set_freezable();
215 add_wait_queue(&ts->irq_wait, &wait);
216 while (!kthread_freezable_should_stop(&frozen)) {
217 unsigned int x, y, p;
218 signed long timeout;
219
220 if (frozen)
221 ignore = true;
222
223 ucb1x00_adc_enable(ts->ucb);
224
225 x = ucb1x00_ts_read_xpos(ts);
226 y = ucb1x00_ts_read_ypos(ts);
227 p = ucb1x00_ts_read_pressure(ts);
228
229 /*
230 * Switch back to interrupt mode.
231 */
232 ucb1x00_ts_mode_int(ts);
233 ucb1x00_adc_disable(ts->ucb);
234
235 msleep(10);
236
237 ucb1x00_enable(ts->ucb);
238
239
240 if (ucb1x00_ts_pen_down(ts)) {
241 set_current_state(TASK_INTERRUPTIBLE);
242
243 spin_lock_irq(&ts->irq_lock);
244 if (ts->irq_disabled) {
245 ts->irq_disabled = 0;
246 enable_irq(ts->ucb->irq_base + UCB_IRQ_TSPX);
247 }
248 spin_unlock_irq(&ts->irq_lock);
249 ucb1x00_disable(ts->ucb);
250
251 /*
252 * If we spat out a valid sample set last time,
253 * spit out a "pen off" sample here.
254 */
255 if (valid) {
256 ucb1x00_ts_event_release(ts);
257 valid = 0;
258 }
259
260 timeout = MAX_SCHEDULE_TIMEOUT;
261 } else {
262 ucb1x00_disable(ts->ucb);
263
264 /*
265 * Filtering is policy. Policy belongs in user
266 * space. We therefore leave it to user space
267 * to do any filtering they please.
268 */
269 if (!ignore) {
270 ucb1x00_ts_evt_add(ts, p, x, y);
271 valid = 1;
272 }
273
274 set_current_state(TASK_INTERRUPTIBLE);
275 timeout = HZ / 100;
276 }
277
278 schedule_timeout(timeout);
279 }
280
281 remove_wait_queue(&ts->irq_wait, &wait);
282
283 ts->rtask = NULL;
284 return 0;
285}
286
287/*
288 * We only detect touch screen _touches_ with this interrupt
289 * handler, and even then we just schedule our task.
290 */
291static irqreturn_t ucb1x00_ts_irq(int irq, void *id)
292{
293 struct ucb1x00_ts *ts = id;
294
295 spin_lock(&ts->irq_lock);
296 ts->irq_disabled = 1;
297 disable_irq_nosync(ts->ucb->irq_base + UCB_IRQ_TSPX);
298 spin_unlock(&ts->irq_lock);
299 wake_up(&ts->irq_wait);
300
301 return IRQ_HANDLED;
302}
303
304static int ucb1x00_ts_open(struct input_dev *idev)
305{
306 struct ucb1x00_ts *ts = input_get_drvdata(idev);
307 unsigned long flags = 0;
308 int ret = 0;
309
310 BUG_ON(ts->rtask);
311
312 if (machine_is_collie())
313 flags = IRQF_TRIGGER_RISING;
314 else
315 flags = IRQF_TRIGGER_FALLING;
316
317 ts->irq_disabled = 0;
318
319 init_waitqueue_head(&ts->irq_wait);
320 ret = request_irq(ts->ucb->irq_base + UCB_IRQ_TSPX, ucb1x00_ts_irq,
321 flags, "ucb1x00-ts", ts);
322 if (ret < 0)
323 goto out;
324
325 /*
326 * If we do this at all, we should allow the user to
327 * measure and read the X and Y resistance at any time.
328 */
329 ucb1x00_adc_enable(ts->ucb);
330 ts->x_res = ucb1x00_ts_read_xres(ts);
331 ts->y_res = ucb1x00_ts_read_yres(ts);
332 ucb1x00_adc_disable(ts->ucb);
333
334 ts->rtask = kthread_run(ucb1x00_thread, ts, "ktsd");
335 if (!IS_ERR(ts->rtask)) {
336 ret = 0;
337 } else {
338 free_irq(ts->ucb->irq_base + UCB_IRQ_TSPX, ts);
339 ts->rtask = NULL;
340 ret = -EFAULT;
341 }
342
343 out:
344 return ret;
345}
346
347/*
348 * Release touchscreen resources. Disable IRQs.
349 */
350static void ucb1x00_ts_close(struct input_dev *idev)
351{
352 struct ucb1x00_ts *ts = input_get_drvdata(idev);
353
354 if (ts->rtask)
355 kthread_stop(ts->rtask);
356
357 ucb1x00_enable(ts->ucb);
358 free_irq(ts->ucb->irq_base + UCB_IRQ_TSPX, ts);
359 ucb1x00_reg_write(ts->ucb, UCB_TS_CR, 0);
360 ucb1x00_disable(ts->ucb);
361}
362
363
364/*
365 * Initialisation.
366 */
367static int ucb1x00_ts_add(struct ucb1x00_dev *dev)
368{
369 struct ucb1x00_ts *ts;
370 struct input_dev *idev;
371 int err;
372
373 ts = kzalloc(sizeof(struct ucb1x00_ts), GFP_KERNEL);
374 idev = input_allocate_device();
375 if (!ts || !idev) {
376 err = -ENOMEM;
377 goto fail;
378 }
379
380 ts->ucb = dev->ucb;
381 ts->idev = idev;
382 ts->adcsync = adcsync ? UCB_SYNC : UCB_NOSYNC;
383 spin_lock_init(&ts->irq_lock);
384
385 idev->name = "Touchscreen panel";
386 idev->id.product = ts->ucb->id;
387 idev->open = ucb1x00_ts_open;
388 idev->close = ucb1x00_ts_close;
389 idev->dev.parent = &ts->ucb->dev;
390
391 idev->evbit[0] = BIT_MASK(EV_ABS) | BIT_MASK(EV_KEY);
392 idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
393
394 input_set_drvdata(idev, ts);
395
396 ucb1x00_adc_enable(ts->ucb);
397 ts->x_res = ucb1x00_ts_read_xres(ts);
398 ts->y_res = ucb1x00_ts_read_yres(ts);
399 ucb1x00_adc_disable(ts->ucb);
400
401 input_set_abs_params(idev, ABS_X, 0, ts->x_res, 0, 0);
402 input_set_abs_params(idev, ABS_Y, 0, ts->y_res, 0, 0);
403 input_set_abs_params(idev, ABS_PRESSURE, 0, 0, 0, 0);
404
405 err = input_register_device(idev);
406 if (err)
407 goto fail;
408
409 dev->priv = ts;
410
411 return 0;
412
413 fail:
414 input_free_device(idev);
415 kfree(ts);
416 return err;
417}
418
419static void ucb1x00_ts_remove(struct ucb1x00_dev *dev)
420{
421 struct ucb1x00_ts *ts = dev->priv;
422
423 input_unregister_device(ts->idev);
424 kfree(ts);
425}
426
427static struct ucb1x00_driver ucb1x00_ts_driver = {
428 .add = ucb1x00_ts_add,
429 .remove = ucb1x00_ts_remove,
430};
431
432static int __init ucb1x00_ts_init(void)
433{
434 return ucb1x00_register_driver(&ucb1x00_ts_driver);
435}
436
437static void __exit ucb1x00_ts_exit(void)
438{
439 ucb1x00_unregister_driver(&ucb1x00_ts_driver);
440}
441
442module_param(adcsync, int, 0444);
443module_init(ucb1x00_ts_init);
444module_exit(ucb1x00_ts_exit);
445
446MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
447MODULE_DESCRIPTION("UCB1x00 touchscreen driver");
448MODULE_LICENSE("GPL");