[PATCH] i386: remove gcc version check for CONFIG_REGPARM
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / mfd / ucb1x00-ts.c
blob79fd062ccb34bee7e02804f4271a82d6291a2950
1 /*
2 * Touchscreen driver for UCB1x00-based touchscreens
4 * Copyright (C) 2001 Russell King, All Rights Reserved.
5 * Copyright (C) 2005 Pavel Machek
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.
11 * 21-Jan-2002 <jco@ict.es> :
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.
20 #include <linux/config.h>
21 #include <linux/module.h>
22 #include <linux/moduleparam.h>
23 #include <linux/init.h>
24 #include <linux/smp.h>
25 #include <linux/smp_lock.h>
26 #include <linux/sched.h>
27 #include <linux/completion.h>
28 #include <linux/delay.h>
29 #include <linux/string.h>
30 #include <linux/input.h>
31 #include <linux/device.h>
32 #include <linux/suspend.h>
33 #include <linux/slab.h>
34 #include <linux/kthread.h>
36 #include <asm/dma.h>
37 #include <asm/semaphore.h>
38 #include <asm/arch/collie.h>
39 #include <asm/mach-types.h>
41 #include "ucb1x00.h"
44 struct ucb1x00_ts {
45 struct input_dev *idev;
46 struct ucb1x00 *ucb;
48 wait_queue_head_t irq_wait;
49 struct task_struct *rtask;
50 u16 x_res;
51 u16 y_res;
53 unsigned int restart:1;
54 unsigned int adcsync:1;
57 static int adcsync;
59 static inline void ucb1x00_ts_evt_add(struct ucb1x00_ts *ts, u16 pressure, u16 x, u16 y)
61 struct input_dev *idev = ts->idev;
62 input_report_abs(idev, ABS_X, x);
63 input_report_abs(idev, ABS_Y, y);
64 input_report_abs(idev, ABS_PRESSURE, pressure);
65 input_sync(idev);
68 static inline void ucb1x00_ts_event_release(struct ucb1x00_ts *ts)
70 struct input_dev *idev = ts->idev;
71 input_report_abs(idev, ABS_PRESSURE, 0);
72 input_sync(idev);
76 * Switch to interrupt mode.
78 static inline void ucb1x00_ts_mode_int(struct ucb1x00_ts *ts)
80 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
81 UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
82 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
83 UCB_TS_CR_MODE_INT);
87 * Switch to pressure mode, and read pressure. We don't need to wait
88 * here, since both plates are being driven.
90 static inline unsigned int ucb1x00_ts_read_pressure(struct ucb1x00_ts *ts)
92 if (machine_is_collie()) {
93 ucb1x00_io_write(ts->ucb, COLLIE_TC35143_GPIO_TBL_CHK, 0);
94 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
95 UCB_TS_CR_TSPX_POW | UCB_TS_CR_TSMX_POW |
96 UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
98 udelay(55);
100 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_AD2, ts->adcsync);
101 } else {
102 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
103 UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
104 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
105 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
107 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
112 * Switch to X position mode and measure Y plate. We switch the plate
113 * configuration in pressure mode, then switch to position mode. This
114 * gives a faster response time. Even so, we need to wait about 55us
115 * for things to stabilise.
117 static inline unsigned int ucb1x00_ts_read_xpos(struct ucb1x00_ts *ts)
119 if (machine_is_collie())
120 ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
121 else {
122 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
123 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
124 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
125 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
126 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
127 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
129 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
130 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
131 UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
133 udelay(55);
135 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPY, ts->adcsync);
139 * Switch to Y position mode and measure X plate. We switch the plate
140 * configuration in pressure mode, then switch to position mode. This
141 * gives a faster response time. Even so, we need to wait about 55us
142 * for things to stabilise.
144 static inline unsigned int ucb1x00_ts_read_ypos(struct ucb1x00_ts *ts)
146 if (machine_is_collie())
147 ucb1x00_io_write(ts->ucb, 0, COLLIE_TC35143_GPIO_TBL_CHK);
148 else {
149 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
150 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
151 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
152 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
153 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
154 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
157 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
158 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
159 UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
161 udelay(55);
163 return ucb1x00_adc_read(ts->ucb, UCB_ADC_INP_TSPX, ts->adcsync);
167 * Switch to X plate resistance mode. Set MX to ground, PX to
168 * supply. Measure current.
170 static inline unsigned int ucb1x00_ts_read_xres(struct ucb1x00_ts *ts)
172 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
173 UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
174 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
175 return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
179 * Switch to Y plate resistance mode. Set MY to ground, PY to
180 * supply. Measure current.
182 static inline unsigned int ucb1x00_ts_read_yres(struct ucb1x00_ts *ts)
184 ucb1x00_reg_write(ts->ucb, UCB_TS_CR,
185 UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
186 UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
187 return ucb1x00_adc_read(ts->ucb, 0, ts->adcsync);
190 static inline int ucb1x00_ts_pen_down(struct ucb1x00_ts *ts)
192 unsigned int val = ucb1x00_reg_read(ts->ucb, UCB_TS_CR);
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));
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).
204 static int ucb1x00_thread(void *_ts)
206 struct ucb1x00_ts *ts = _ts;
207 struct task_struct *tsk = current;
208 DECLARE_WAITQUEUE(wait, tsk);
209 int valid;
212 * We could run as a real-time thread. However, thus far
213 * this doesn't seem to be necessary.
215 // tsk->policy = SCHED_FIFO;
216 // tsk->rt_priority = 1;
218 valid = 0;
220 add_wait_queue(&ts->irq_wait, &wait);
221 while (!kthread_should_stop()) {
222 unsigned int x, y, p;
223 signed long timeout;
225 ts->restart = 0;
227 ucb1x00_adc_enable(ts->ucb);
229 x = ucb1x00_ts_read_xpos(ts);
230 y = ucb1x00_ts_read_ypos(ts);
231 p = ucb1x00_ts_read_pressure(ts);
234 * Switch back to interrupt mode.
236 ucb1x00_ts_mode_int(ts);
237 ucb1x00_adc_disable(ts->ucb);
239 msleep(10);
241 ucb1x00_enable(ts->ucb);
244 if (ucb1x00_ts_pen_down(ts)) {
245 set_task_state(tsk, TASK_INTERRUPTIBLE);
247 ucb1x00_enable_irq(ts->ucb, UCB_IRQ_TSPX, machine_is_collie() ? UCB_RISING : UCB_FALLING);
248 ucb1x00_disable(ts->ucb);
251 * If we spat out a valid sample set last time,
252 * spit out a "pen off" sample here.
254 if (valid) {
255 ucb1x00_ts_event_release(ts);
256 valid = 0;
259 timeout = MAX_SCHEDULE_TIMEOUT;
260 } else {
261 ucb1x00_disable(ts->ucb);
264 * Filtering is policy. Policy belongs in user
265 * space. We therefore leave it to user space
266 * to do any filtering they please.
268 if (!ts->restart) {
269 ucb1x00_ts_evt_add(ts, p, x, y);
270 valid = 1;
273 set_task_state(tsk, TASK_INTERRUPTIBLE);
274 timeout = HZ / 100;
277 try_to_freeze();
279 schedule_timeout(timeout);
282 remove_wait_queue(&ts->irq_wait, &wait);
284 ts->rtask = NULL;
285 return 0;
289 * We only detect touch screen _touches_ with this interrupt
290 * handler, and even then we just schedule our task.
292 static void ucb1x00_ts_irq(int idx, void *id)
294 struct ucb1x00_ts *ts = id;
295 ucb1x00_disable_irq(ts->ucb, UCB_IRQ_TSPX, UCB_FALLING);
296 wake_up(&ts->irq_wait);
299 static int ucb1x00_ts_open(struct input_dev *idev)
301 struct ucb1x00_ts *ts = idev->private;
302 int ret = 0;
304 BUG_ON(ts->rtask);
306 init_waitqueue_head(&ts->irq_wait);
307 ret = ucb1x00_hook_irq(ts->ucb, UCB_IRQ_TSPX, ucb1x00_ts_irq, ts);
308 if (ret < 0)
309 goto out;
312 * If we do this at all, we should allow the user to
313 * measure and read the X and Y resistance at any time.
315 ucb1x00_adc_enable(ts->ucb);
316 ts->x_res = ucb1x00_ts_read_xres(ts);
317 ts->y_res = ucb1x00_ts_read_yres(ts);
318 ucb1x00_adc_disable(ts->ucb);
320 ts->rtask = kthread_run(ucb1x00_thread, ts, "ktsd");
321 if (!IS_ERR(ts->rtask)) {
322 ret = 0;
323 } else {
324 ucb1x00_free_irq(ts->ucb, UCB_IRQ_TSPX, ts);
325 ts->rtask = NULL;
326 ret = -EFAULT;
329 out:
330 return ret;
334 * Release touchscreen resources. Disable IRQs.
336 static void ucb1x00_ts_close(struct input_dev *idev)
338 struct ucb1x00_ts *ts = idev->private;
340 if (ts->rtask)
341 kthread_stop(ts->rtask);
343 ucb1x00_enable(ts->ucb);
344 ucb1x00_free_irq(ts->ucb, UCB_IRQ_TSPX, ts);
345 ucb1x00_reg_write(ts->ucb, UCB_TS_CR, 0);
346 ucb1x00_disable(ts->ucb);
349 #ifdef CONFIG_PM
350 static int ucb1x00_ts_resume(struct ucb1x00_dev *dev)
352 struct ucb1x00_ts *ts = dev->priv;
354 if (ts->rtask != NULL) {
356 * Restart the TS thread to ensure the
357 * TS interrupt mode is set up again
358 * after sleep.
360 ts->restart = 1;
361 wake_up(&ts->irq_wait);
363 return 0;
365 #else
366 #define ucb1x00_ts_resume NULL
367 #endif
371 * Initialisation.
373 static int ucb1x00_ts_add(struct ucb1x00_dev *dev)
375 struct ucb1x00_ts *ts;
377 ts = kzalloc(sizeof(struct ucb1x00_ts), GFP_KERNEL);
378 if (!ts)
379 return -ENOMEM;
381 ts->idev = input_allocate_device();
382 if (!ts->idev) {
383 kfree(ts);
384 return -ENOMEM;
387 ts->ucb = dev->ucb;
388 ts->adcsync = adcsync ? UCB_SYNC : UCB_NOSYNC;
390 ts->idev->private = ts;
391 ts->idev->name = "Touchscreen panel";
392 ts->idev->id.product = ts->ucb->id;
393 ts->idev->open = ucb1x00_ts_open;
394 ts->idev->close = ucb1x00_ts_close;
396 __set_bit(EV_ABS, ts->idev->evbit);
397 __set_bit(ABS_X, ts->idev->absbit);
398 __set_bit(ABS_Y, ts->idev->absbit);
399 __set_bit(ABS_PRESSURE, ts->idev->absbit);
401 input_register_device(ts->idev);
403 dev->priv = ts;
405 return 0;
408 static void ucb1x00_ts_remove(struct ucb1x00_dev *dev)
410 struct ucb1x00_ts *ts = dev->priv;
412 input_unregister_device(ts->idev);
413 kfree(ts);
416 static struct ucb1x00_driver ucb1x00_ts_driver = {
417 .add = ucb1x00_ts_add,
418 .remove = ucb1x00_ts_remove,
419 .resume = ucb1x00_ts_resume,
422 static int __init ucb1x00_ts_init(void)
424 return ucb1x00_register_driver(&ucb1x00_ts_driver);
427 static void __exit ucb1x00_ts_exit(void)
429 ucb1x00_unregister_driver(&ucb1x00_ts_driver);
432 module_param(adcsync, int, 0444);
433 module_init(ucb1x00_ts_init);
434 module_exit(ucb1x00_ts_exit);
436 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
437 MODULE_DESCRIPTION("UCB1x00 touchscreen driver");
438 MODULE_LICENSE("GPL");