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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/*
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");