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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/smp.h>
24#include <linux/sched.h>
25#include <linux/completion.h>
26#include <linux/delay.h>
27#include <linux/string.h>
28#include <linux/input.h>
29#include <linux/device.h>
30#include <linux/freezer.h>
31#include <linux/slab.h>
32#include <linux/kthread.h>
33#include <linux/mfd/ucb1x00.h>
34
35#include <mach/dma.h>
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 wait_queue_head_t irq_wait;
46 struct task_struct *rtask;
47 u16 x_res;
48 u16 y_res;
49
50 unsigned int restart:1;
51 unsigned int adcsync:1;
52};
53
54static int adcsync;
55
56static inline void ucb1x00_ts_evt_add(struct ucb1x00_ts *ts, u16 pressure, u16 x, u16 y)
57{
58 struct input_dev *idev = ts->idev;
59
60 input_report_abs(idev, ABS_X, x);
61 input_report_abs(idev, ABS_Y, y);
62 input_report_abs(idev, ABS_PRESSURE, pressure);
63 input_report_key(idev, BTN_TOUCH, 1);
64 input_sync(idev);
65}
66
67static inline void ucb1x00_ts_event_release(struct ucb1x00_ts *ts)
68{
69 struct input_dev *idev = ts->idev;
70
71 input_report_abs(idev, ABS_PRESSURE, 0);
72 input_report_key(idev, BTN_TOUCH, 0);
73 input_sync(idev);
74}
75
76/*
77 * Switch to interrupt mode.
78 */
79static inline void ucb1x00_ts_mode_int(struct ucb1x00_ts *ts)
80{
81 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
82 UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
83 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
84 UCB_TS_CR_MODE_INT);
85}
86
87/*
88 * Switch to pressure mode, and read pressure. We don't need to wait
89 * here, since both plates are being driven.
90 */
91static inline unsigned int ucb1x00_ts_read_pressure(struct ucb1x00_ts *ts)
92{
93 if (machine_is_collie()) {
94 ucb1x00_io_write(ts->ucb, COLLIE_TC35143_GPIO_TBL_CHK, 0);
95 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
96 UCB_TS_CR_TSPX_POW | UCB_TS_CR_TSMX_POW |
97 UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
98
99 udelay(55);
100
101 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_AD2, ts->adcsync);
102 } else {
103 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
104 UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
105 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
106 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
107
108 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
109 }
110}
111
112/*
113 * Switch to X position mode and measure Y plate. We switch the plate
114 * configuration in pressure mode, then switch to position mode. This
115 * gives a faster response time. Even so, we need to wait about 55us
116 * for things to stabilise.
117 */
118static inline unsigned int ucb1x00_ts_read_xpos(struct ucb1x00_ts *ts)
119{
120 if (machine_is_collie())
121 ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
122 else {
123 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
124 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
125 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
126 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
127 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
128 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
129 }
130 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
131 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
132 UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
133
134 udelay(55);
135
136 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
137}
138
139/*
140 * Switch to Y position mode and measure X plate. We switch the plate
141 * configuration in pressure mode, then switch to position mode. This
142 * gives a faster response time. Even so, we need to wait about 55us
143 * for things to stabilise.
144 */
145static inline unsigned int ucb1x00_ts_read_ypos(struct ucb1x00_ts *ts)
146{
147 if (machine_is_collie())
148 ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
149 else {
150 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
151 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
152 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
153 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
154 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
155 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
156 }
157
158 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
159 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
160 UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
161
162 udelay(55);
163
164 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPX, ts->adcsync);
165}
166
167/*
168 * Switch to X plate resistance mode. Set MX to ground, PX to
169 * supply. Measure current.
170 */
171static inline unsigned int ucb1x00_ts_read_xres(struct ucb1x00_ts *ts)
172{
173 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
174 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
175 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
176 return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
177}
178
179/*
180 * Switch to Y plate resistance mode. Set MY to ground, PY to
181 * supply. Measure current.
182 */
183static inline unsigned int ucb1x00_ts_read_yres(struct ucb1x00_ts *ts)
184{
185 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
186 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
187 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
188 return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
189}
190
191static inline int ucb1x00_ts_pen_down(struct ucb1x00_ts *ts)
192{
193 unsigned int val = ucb1x00_reg_read(ts->ucb, UCB_TS_CR);
194
195 if (machine_is_collie())
196 return (!(val & (UCB_TS_CR_TSPX_LOW)));
197 else
198 return (val & (UCB_TS_CR_TSPX_LOW | UCB_TS_CR_TSMX_LOW));
199}
200
201/*
202 * This is a RT kernel thread that handles the ADC accesses
203 * (mainly so we can use semaphores in the UCB1200 core code
204 * to serialise accesses to the ADC).
205 */
206static int ucb1x00_thread(void *_ts)
207{
208 struct ucb1x00_ts *ts = _ts;
209 DECLARE_WAITQUEUE(wait, current);
210 int valid = 0;
211
212 set_freezable();
213 add_wait_queue(&ts->irq_wait, &wait);
214 while (!kthread_should_stop()) {
215 unsigned int x, y, p;
216 signed long timeout;
217
218 ts->restart = 0;
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 ucb1x00_enable_irq(ts->ucb, UCB_IRQ_TSPX, machine_is_collie() ? UCB_RISING : UCB_FALLING);
241 ucb1x00_disable(ts->ucb);
242
243 /*
244 * If we spat out a valid sample set last time,
245 * spit out a "pen off" sample here.
246 */
247 if (valid) {
248 ucb1x00_ts_event_release(ts);
249 valid = 0;
250 }
251
252 timeout = MAX_SCHEDULE_TIMEOUT;
253 } else {
254 ucb1x00_disable(ts->ucb);
255
256 /*
257 * Filtering is policy. Policy belongs in user
258 * space. We therefore leave it to user space
259 * to do any filtering they please.
260 */
261 if (!ts->restart) {
262 ucb1x00_ts_evt_add(ts, p, x, y);
263 valid = 1;
264 }
265
266 set_current_state(TASK_INTERRUPTIBLE);
267 timeout = HZ / 100;
268 }
269
270 try_to_freeze();
271
272 schedule_timeout(timeout);
273 }
274
275 remove_wait_queue(&ts->irq_wait, &wait);
276
277 ts->rtask = NULL;
278 return 0;
279}
280
281/*
282 * We only detect touch screen _touches_ with this interrupt
283 * handler, and even then we just schedule our task.
284 */
285static void ucb1x00_ts_irq(int idx, void *id)
286{
287 struct ucb1x00_ts *ts = id;
288
289 ucb1x00_disable_irq(ts->ucb, UCB_IRQ_TSPX, UCB_FALLING);
290 wake_up(&ts->irq_wait);
291}
292
293static int ucb1x00_ts_open(struct input_dev *idev)
294{
295 struct ucb1x00_ts *ts = input_get_drvdata(idev);
296 int ret = 0;
297
298 BUG_ON(ts->rtask);
299
300 init_waitqueue_head(&ts->irq_wait);
301 ret = ucb1x00_hook_irq(ts->ucb, UCB_IRQ_TSPX, ucb1x00_ts_irq, ts);
302 if (ret < 0)
303 goto out;
304
305 /*
306 * If we do this at all, we should allow the user to
307 * measure and read the X and Y resistance at any time.
308 */
309 ucb1x00_adc_enable(ts->ucb);
310 ts->x_res = ucb1x00_ts_read_xres(ts);
311 ts->y_res = ucb1x00_ts_read_yres(ts);
312 ucb1x00_adc_disable(ts->ucb);
313
314 ts->rtask = kthread_run(ucb1x00_thread, ts, "ktsd");
315 if (!IS_ERR(ts->rtask)) {
316 ret = 0;
317 } else {
318 ucb1x00_free_irq(ts->ucb, UCB_IRQ_TSPX, ts);
319 ts->rtask = NULL;
320 ret = -EFAULT;
321 }
322
323 out:
324 return ret;
325}
326
327/*
328 * Release touchscreen resources. Disable IRQs.
329 */
330static void ucb1x00_ts_close(struct input_dev *idev)
331{
332 struct ucb1x00_ts *ts = input_get_drvdata(idev);
333
334 if (ts->rtask)
335 kthread_stop(ts->rtask);
336
337 ucb1x00_enable(ts->ucb);
338 ucb1x00_free_irq(ts->ucb, UCB_IRQ_TSPX, ts);
339 ucb1x00_reg_write(ts->ucb, UCB_TS_CR, 0);
340 ucb1x00_disable(ts->ucb);
341}
342
343#ifdef CONFIG_PM
344static int ucb1x00_ts_resume(struct ucb1x00_dev *dev)
345{
346 struct ucb1x00_ts *ts = dev->priv;
347
348 if (ts->rtask != NULL) {
349 /*
350 * Restart the TS thread to ensure the
351 * TS interrupt mode is set up again
352 * after sleep.
353 */
354 ts->restart = 1;
355 wake_up(&ts->irq_wait);
356 }
357 return 0;
358}
359#else
360#define ucb1x00_ts_resume NULL
361#endif
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
384 idev->name = "Touchscreen panel";
385 idev->id.product = ts->ucb->id;
386 idev->open = ucb1x00_ts_open;
387 idev->close = ucb1x00_ts_close;
388
389 idev->evbit[0] = BIT_MASK(EV_ABS) | BIT_MASK(EV_KEY);
390 idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
391
392 input_set_drvdata(idev, ts);
393
394 ucb1x00_adc_enable(ts->ucb);
395 ts->x_res = ucb1x00_ts_read_xres(ts);
396 ts->y_res = ucb1x00_ts_read_yres(ts);
397 ucb1x00_adc_disable(ts->ucb);
398
399 input_set_abs_params(idev, ABS_X, 0, ts->x_res, 0, 0);
400 input_set_abs_params(idev, ABS_Y, 0, ts->y_res, 0, 0);
401 input_set_abs_params(idev, ABS_PRESSURE, 0, 0, 0, 0);
402
403 err = input_register_device(idev);
404 if (err)
405 goto fail;
406
407 dev->priv = ts;
408
409 return 0;
410
411 fail:
412 input_free_device(idev);
413 kfree(ts);
414 return err;
415}
416
417static void ucb1x00_ts_remove(struct ucb1x00_dev *dev)
418{
419 struct ucb1x00_ts *ts = dev->priv;
420
421 input_unregister_device(ts->idev);
422 kfree(ts);
423}
424
425static struct ucb1x00_driver ucb1x00_ts_driver = {
426 .add = ucb1x00_ts_add,
427 .remove = ucb1x00_ts_remove,
428 .resume = ucb1x00_ts_resume,
429};
430
431static int __init ucb1x00_ts_init(void)
432{
433 return ucb1x00_register_driver(&ucb1x00_ts_driver);
434}
435
436static void __exit ucb1x00_ts_exit(void)
437{
438 ucb1x00_unregister_driver(&ucb1x00_ts_driver);
439}
440
441module_param(adcsync, int, 0444);
442module_init(ucb1x00_ts_init);
443module_exit(ucb1x00_ts_exit);
444
445MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
446MODULE_DESCRIPTION("UCB1x00 touchscreen driver");
447MODULE_LICENSE("GPL");
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");