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Input: da9034-ts - add Bin Yang as co-author of the driver
[karo-tx-linux.git] / drivers / input / touchscreen / da9034-ts.c
1 /*
2  * Touchscreen driver for Dialog Semiconductor DA9034
3  *
4  * Copyright (C) 2006-2008 Marvell International Ltd.
5  *      Fengwei Yin <fengwei.yin@marvell.com>
6  *      Bin Yang  <bin.yang@marvell.com>
7  *      Eric Miao <eric.miao@marvell.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/delay.h>
18 #include <linux/platform_device.h>
19 #include <linux/input.h>
20 #include <linux/workqueue.h>
21 #include <linux/mfd/da903x.h>
22
23 #define DA9034_MANUAL_CTRL      0x50
24 #define DA9034_LDO_ADC_EN       (1 << 4)
25
26 #define DA9034_AUTO_CTRL1       0x51
27
28 #define DA9034_AUTO_CTRL2       0x52
29 #define DA9034_AUTO_TSI_EN      (1 << 3)
30 #define DA9034_PEN_DETECT       (1 << 4)
31
32 #define DA9034_TSI_CTRL1        0x53
33 #define DA9034_TSI_CTRL2        0x54
34 #define DA9034_TSI_X_MSB        0x6c
35 #define DA9034_TSI_Y_MSB        0x6d
36 #define DA9034_TSI_XY_LSB       0x6e
37
38 enum {
39         STATE_IDLE,     /* wait for pendown */
40         STATE_BUSY,     /* TSI busy sampling */
41         STATE_STOP,     /* sample available */
42         STATE_WAIT,     /* Wait to start next sample */
43 };
44
45 enum {
46         EVENT_PEN_DOWN,
47         EVENT_PEN_UP,
48         EVENT_TSI_READY,
49         EVENT_TIMEDOUT,
50 };
51
52 struct da9034_touch {
53         struct device           *da9034_dev;
54         struct input_dev        *input_dev;
55
56         struct delayed_work     tsi_work;
57         struct notifier_block   notifier;
58
59         int     state;
60
61         int     interval_ms;
62         int     x_inverted;
63         int     y_inverted;
64
65         int     last_x;
66         int     last_y;
67 };
68
69 static inline int is_pen_down(struct da9034_touch *touch)
70 {
71         return da903x_query_status(touch->da9034_dev, DA9034_STATUS_PEN_DOWN);
72 }
73
74 static inline int detect_pen_down(struct da9034_touch *touch, int on)
75 {
76         if (on)
77                 return da903x_set_bits(touch->da9034_dev,
78                                 DA9034_AUTO_CTRL2, DA9034_PEN_DETECT);
79         else
80                 return da903x_clr_bits(touch->da9034_dev,
81                                 DA9034_AUTO_CTRL2, DA9034_PEN_DETECT);
82 }
83
84 static int read_tsi(struct da9034_touch *touch)
85 {
86         uint8_t _x, _y, _v;
87         int ret;
88
89         ret = da903x_read(touch->da9034_dev, DA9034_TSI_X_MSB, &_x);
90         if (ret)
91                 return ret;
92
93         ret = da903x_read(touch->da9034_dev, DA9034_TSI_Y_MSB, &_y);
94         if (ret)
95                 return ret;
96
97         ret = da903x_read(touch->da9034_dev, DA9034_TSI_XY_LSB, &_v);
98         if (ret)
99                 return ret;
100
101         touch->last_x = ((_x << 2) & 0x3fc) | (_v & 0x3);
102         touch->last_y = ((_y << 2) & 0x3fc) | ((_v & 0xc) >> 2);
103
104         return 0;
105 }
106
107 static inline int start_tsi(struct da9034_touch *touch)
108 {
109         return da903x_set_bits(touch->da9034_dev,
110                         DA9034_AUTO_CTRL2, DA9034_AUTO_TSI_EN);
111 }
112
113 static inline int stop_tsi(struct da9034_touch *touch)
114 {
115         return da903x_clr_bits(touch->da9034_dev,
116                         DA9034_AUTO_CTRL2, DA9034_AUTO_TSI_EN);
117 }
118
119 static inline void report_pen_down(struct da9034_touch *touch)
120 {
121         int x = touch->last_x;
122         int y = touch->last_y;
123
124         x &= 0xfff;
125         if (touch->x_inverted)
126                 x = 1024 - x;
127         y &= 0xfff;
128         if (touch->y_inverted)
129                 y = 1024 - y;
130
131         input_report_abs(touch->input_dev, ABS_X, x);
132         input_report_abs(touch->input_dev, ABS_Y, y);
133         input_report_key(touch->input_dev, BTN_TOUCH, 1);
134
135         input_sync(touch->input_dev);
136 }
137
138 static inline void report_pen_up(struct da9034_touch *touch)
139 {
140         input_report_key(touch->input_dev, BTN_TOUCH, 0);
141         input_sync(touch->input_dev);
142 }
143
144 static void da9034_event_handler(struct da9034_touch *touch, int event)
145 {
146         int err;
147
148         switch (touch->state) {
149         case STATE_IDLE:
150                 if (event != EVENT_PEN_DOWN)
151                         break;
152
153                 /* Enable auto measurement of the TSI, this will
154                  * automatically disable pen down detection
155                  */
156                 err = start_tsi(touch);
157                 if (err)
158                         goto err_reset;
159
160                 touch->state = STATE_BUSY;
161                 break;
162
163         case STATE_BUSY:
164                 if (event != EVENT_TSI_READY)
165                         break;
166
167                 err = read_tsi(touch);
168                 if (err)
169                         goto err_reset;
170
171                 /* Disable auto measurement of the TSI, so that
172                  * pen down status will be available
173                  */
174                 err = stop_tsi(touch);
175                 if (err)
176                         goto err_reset;
177
178                 touch->state = STATE_STOP;
179                 break;
180
181         case STATE_STOP:
182                 if (event == EVENT_PEN_DOWN) {
183                         report_pen_down(touch);
184                         schedule_delayed_work(&touch->tsi_work,
185                                 msecs_to_jiffies(touch->interval_ms));
186                         touch->state = STATE_WAIT;
187                 }
188
189                 if (event == EVENT_PEN_UP) {
190                         report_pen_up(touch);
191                         touch->state = STATE_IDLE;
192                 }
193
194                 input_sync(touch->input_dev);
195                 break;
196
197         case STATE_WAIT:
198                 if (event != EVENT_TIMEDOUT)
199                         break;
200
201                 if (is_pen_down(touch)) {
202                         start_tsi(touch);
203                         touch->state = STATE_BUSY;
204                 } else
205                         touch->state = STATE_IDLE;
206                 break;
207         }
208         return;
209
210 err_reset:
211         touch->state = STATE_IDLE;
212         stop_tsi(touch);
213         detect_pen_down(touch, 1);
214 }
215
216 static void da9034_tsi_work(struct work_struct *work)
217 {
218         struct da9034_touch *touch =
219                 container_of(work, struct da9034_touch, tsi_work.work);
220
221         da9034_event_handler(touch, EVENT_TIMEDOUT);
222 }
223
224 static int da9034_touch_notifier(struct notifier_block *nb,
225                                  unsigned long event, void *data)
226 {
227         struct da9034_touch *touch =
228                 container_of(nb, struct da9034_touch, notifier);
229
230         if (event & DA9034_EVENT_PEN_DOWN) {
231                 if (is_pen_down(touch))
232                         da9034_event_handler(touch, EVENT_PEN_DOWN);
233                 else
234                         da9034_event_handler(touch, EVENT_PEN_UP);
235         }
236
237         if (event & DA9034_EVENT_TSI_READY)
238                 da9034_event_handler(touch, EVENT_TSI_READY);
239
240         return 0;
241 }
242
243 static int da9034_touch_open(struct input_dev *dev)
244 {
245         struct da9034_touch *touch = input_get_drvdata(dev);
246         int ret;
247
248         ret = da903x_register_notifier(touch->da9034_dev, &touch->notifier,
249                         DA9034_EVENT_PEN_DOWN | DA9034_EVENT_TSI_READY);
250         if (ret)
251                 return -EBUSY;
252
253         /* Enable ADC LDO */
254         ret = da903x_set_bits(touch->da9034_dev,
255                         DA9034_MANUAL_CTRL, DA9034_LDO_ADC_EN);
256         if (ret)
257                 return ret;
258
259         /* TSI_DELAY: 3 slots, TSI_SKIP: 3 slots */
260         ret = da903x_write(touch->da9034_dev, DA9034_TSI_CTRL1, 0x1b);
261         if (ret)
262                 return ret;
263
264         ret = da903x_write(touch->da9034_dev, DA9034_TSI_CTRL2, 0x00);
265         if (ret)
266                 return ret;
267
268         touch->state = STATE_IDLE;
269         detect_pen_down(touch, 1);
270
271         return 0;
272 }
273
274 static void da9034_touch_close(struct input_dev *dev)
275 {
276         struct da9034_touch *touch = input_get_drvdata(dev);
277
278         da903x_unregister_notifier(touch->da9034_dev, &touch->notifier,
279                         DA9034_EVENT_PEN_DOWN | DA9034_EVENT_TSI_READY);
280
281         cancel_delayed_work_sync(&touch->tsi_work);
282
283         touch->state = STATE_IDLE;
284         stop_tsi(touch);
285         detect_pen_down(touch, 0);
286
287         /* Disable ADC LDO */
288         da903x_clr_bits(touch->da9034_dev,
289                         DA9034_MANUAL_CTRL, DA9034_LDO_ADC_EN);
290 }
291
292
293 static int __devinit da9034_touch_probe(struct platform_device *pdev)
294 {
295         struct da9034_touch_pdata *pdata = pdev->dev.platform_data;
296         struct da9034_touch *touch;
297         struct input_dev *input_dev;
298         int ret;
299
300         touch = kzalloc(sizeof(struct da9034_touch), GFP_KERNEL);
301         if (touch == NULL) {
302                 dev_err(&pdev->dev, "failed to allocate driver data\n");
303                 return -ENOMEM;
304         }
305
306         touch->da9034_dev = pdev->dev.parent;
307
308         if (pdata) {
309                 touch->interval_ms      = pdata->interval_ms;
310                 touch->x_inverted       = pdata->x_inverted;
311                 touch->y_inverted       = pdata->y_inverted;
312         } else
313                 /* fallback into default */
314                 touch->interval_ms      = 10;
315
316         INIT_DELAYED_WORK(&touch->tsi_work, da9034_tsi_work);
317         touch->notifier.notifier_call = da9034_touch_notifier;
318
319         input_dev = input_allocate_device();
320         if (!input_dev) {
321                 dev_err(&pdev->dev, "failed to allocate input device\n");
322                 ret = -ENOMEM;
323                 goto err_free_touch;
324         }
325
326         input_dev->name         = pdev->name;
327         input_dev->open         = da9034_touch_open;
328         input_dev->close        = da9034_touch_close;
329         input_dev->dev.parent   = &pdev->dev;
330
331         __set_bit(EV_ABS, input_dev->evbit);
332         __set_bit(ABS_X, input_dev->absbit);
333         __set_bit(ABS_Y, input_dev->absbit);
334         input_set_abs_params(input_dev, ABS_X, 0, 1023, 0, 0);
335         input_set_abs_params(input_dev, ABS_Y, 0, 1023, 0, 0);
336
337         __set_bit(EV_KEY, input_dev->evbit);
338         __set_bit(BTN_TOUCH, input_dev->keybit);
339
340         touch->input_dev = input_dev;
341         input_set_drvdata(input_dev, touch);
342
343         ret = input_register_device(input_dev);
344         if (ret)
345                 goto err_free_input;
346
347         platform_set_drvdata(pdev, touch);
348         return 0;
349
350 err_free_input:
351         input_free_device(input_dev);
352 err_free_touch:
353         kfree(touch);
354         return ret;
355 }
356
357 static int __devexit da9034_touch_remove(struct platform_device *pdev)
358 {
359         struct da9034_touch *touch = platform_get_drvdata(pdev);
360
361         input_unregister_device(touch->input_dev);
362         kfree(touch);
363
364         return 0;
365 }
366
367 static struct platform_driver da9034_touch_driver = {
368         .driver = {
369                 .name   = "da9034-touch",
370                 .owner  = THIS_MODULE,
371         },
372         .probe          = da9034_touch_probe,
373         .remove         = __devexit_p(da9034_touch_remove),
374 };
375
376 static int __init da9034_touch_init(void)
377 {
378         return platform_driver_register(&da9034_touch_driver);
379 }
380 module_init(da9034_touch_init);
381
382 static void __exit da9034_touch_exit(void)
383 {
384         platform_driver_unregister(&da9034_touch_driver);
385 }
386 module_exit(da9034_touch_exit);
387
388 MODULE_DESCRIPTION("Touchscreen driver for Dialog Semiconductor DA9034");
389 MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>, Bin Yang <bin.yang@marvell.com>");
390 MODULE_LICENSE("GPL");
391 MODULE_ALIAS("platform:da9034-touch");