Version:  2.0.40 2.2.26 2.4.37 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16

Linux/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/delay.h>
 17 #include <linux/platform_device.h>
 18 #include <linux/input.h>
 19 #include <linux/workqueue.h>
 20 #include <linux/mfd/da903x.h>
 21 #include <linux/slab.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 
180                 /* FIXME: PEN_{UP/DOWN} events are expected to be
181                  * available by stopping TSI, but this is found not
182                  * always true, delay and simulate such an event
183                  * here is more reliable
184                  */
185                 mdelay(1);
186                 da9034_event_handler(touch,
187                                      is_pen_down(touch) ? EVENT_PEN_DOWN :
188                                                           EVENT_PEN_UP);
189                 break;
190 
191         case STATE_STOP:
192                 if (event == EVENT_PEN_DOWN) {
193                         report_pen_down(touch);
194                         schedule_delayed_work(&touch->tsi_work,
195                                 msecs_to_jiffies(touch->interval_ms));
196                         touch->state = STATE_WAIT;
197                 }
198 
199                 if (event == EVENT_PEN_UP) {
200                         report_pen_up(touch);
201                         touch->state = STATE_IDLE;
202                 }
203                 break;
204 
205         case STATE_WAIT:
206                 if (event != EVENT_TIMEDOUT)
207                         break;
208 
209                 if (is_pen_down(touch)) {
210                         start_tsi(touch);
211                         touch->state = STATE_BUSY;
212                 } else {
213                         report_pen_up(touch);
214                         touch->state = STATE_IDLE;
215                 }
216                 break;
217         }
218         return;
219 
220 err_reset:
221         touch->state = STATE_IDLE;
222         stop_tsi(touch);
223         detect_pen_down(touch, 1);
224 }
225 
226 static void da9034_tsi_work(struct work_struct *work)
227 {
228         struct da9034_touch *touch =
229                 container_of(work, struct da9034_touch, tsi_work.work);
230 
231         da9034_event_handler(touch, EVENT_TIMEDOUT);
232 }
233 
234 static int da9034_touch_notifier(struct notifier_block *nb,
235                                  unsigned long event, void *data)
236 {
237         struct da9034_touch *touch =
238                 container_of(nb, struct da9034_touch, notifier);
239 
240         if (event & DA9034_EVENT_TSI_READY)
241                 da9034_event_handler(touch, EVENT_TSI_READY);
242 
243         if ((event & DA9034_EVENT_PEN_DOWN) && touch->state == STATE_IDLE)
244                 da9034_event_handler(touch, EVENT_PEN_DOWN);
245 
246         return 0;
247 }
248 
249 static int da9034_touch_open(struct input_dev *dev)
250 {
251         struct da9034_touch *touch = input_get_drvdata(dev);
252         int ret;
253 
254         ret = da903x_register_notifier(touch->da9034_dev, &touch->notifier,
255                         DA9034_EVENT_PEN_DOWN | DA9034_EVENT_TSI_READY);
256         if (ret)
257                 return -EBUSY;
258 
259         /* Enable ADC LDO */
260         ret = da903x_set_bits(touch->da9034_dev,
261                         DA9034_MANUAL_CTRL, DA9034_LDO_ADC_EN);
262         if (ret)
263                 return ret;
264 
265         /* TSI_DELAY: 3 slots, TSI_SKIP: 3 slots */
266         ret = da903x_write(touch->da9034_dev, DA9034_TSI_CTRL1, 0x1b);
267         if (ret)
268                 return ret;
269 
270         ret = da903x_write(touch->da9034_dev, DA9034_TSI_CTRL2, 0x00);
271         if (ret)
272                 return ret;
273 
274         touch->state = STATE_IDLE;
275         detect_pen_down(touch, 1);
276 
277         return 0;
278 }
279 
280 static void da9034_touch_close(struct input_dev *dev)
281 {
282         struct da9034_touch *touch = input_get_drvdata(dev);
283 
284         da903x_unregister_notifier(touch->da9034_dev, &touch->notifier,
285                         DA9034_EVENT_PEN_DOWN | DA9034_EVENT_TSI_READY);
286 
287         cancel_delayed_work_sync(&touch->tsi_work);
288 
289         touch->state = STATE_IDLE;
290         stop_tsi(touch);
291         detect_pen_down(touch, 0);
292 
293         /* Disable ADC LDO */
294         da903x_clr_bits(touch->da9034_dev,
295                         DA9034_MANUAL_CTRL, DA9034_LDO_ADC_EN);
296 }
297 
298 
299 static int da9034_touch_probe(struct platform_device *pdev)
300 {
301         struct da9034_touch_pdata *pdata = dev_get_platdata(&pdev->dev);
302         struct da9034_touch *touch;
303         struct input_dev *input_dev;
304         int error;
305 
306         touch = devm_kzalloc(&pdev->dev, sizeof(struct da9034_touch),
307                              GFP_KERNEL);
308         if (!touch) {
309                 dev_err(&pdev->dev, "failed to allocate driver data\n");
310                 return -ENOMEM;
311         }
312 
313         touch->da9034_dev = pdev->dev.parent;
314 
315         if (pdata) {
316                 touch->interval_ms      = pdata->interval_ms;
317                 touch->x_inverted       = pdata->x_inverted;
318                 touch->y_inverted       = pdata->y_inverted;
319         } else {
320                 /* fallback into default */
321                 touch->interval_ms      = 10;
322         }
323 
324         INIT_DELAYED_WORK(&touch->tsi_work, da9034_tsi_work);
325         touch->notifier.notifier_call = da9034_touch_notifier;
326 
327         input_dev = devm_input_allocate_device(&pdev->dev);
328         if (!input_dev) {
329                 dev_err(&pdev->dev, "failed to allocate input device\n");
330                 return -ENOMEM;
331         }
332 
333         input_dev->name         = pdev->name;
334         input_dev->open         = da9034_touch_open;
335         input_dev->close        = da9034_touch_close;
336         input_dev->dev.parent   = &pdev->dev;
337 
338         __set_bit(EV_ABS, input_dev->evbit);
339         __set_bit(ABS_X, input_dev->absbit);
340         __set_bit(ABS_Y, input_dev->absbit);
341         input_set_abs_params(input_dev, ABS_X, 0, 1023, 0, 0);
342         input_set_abs_params(input_dev, ABS_Y, 0, 1023, 0, 0);
343 
344         __set_bit(EV_KEY, input_dev->evbit);
345         __set_bit(BTN_TOUCH, input_dev->keybit);
346 
347         touch->input_dev = input_dev;
348         input_set_drvdata(input_dev, touch);
349 
350         error = input_register_device(input_dev);
351         if (error)
352                 return error;
353 
354         return 0;
355 }
356 
357 static struct platform_driver da9034_touch_driver = {
358         .driver = {
359                 .name   = "da9034-touch",
360                 .owner  = THIS_MODULE,
361         },
362         .probe          = da9034_touch_probe,
363 };
364 module_platform_driver(da9034_touch_driver);
365 
366 MODULE_DESCRIPTION("Touchscreen driver for Dialog Semiconductor DA9034");
367 MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>, Bin Yang <bin.yang@marvell.com>");
368 MODULE_LICENSE("GPL");
369 MODULE_ALIAS("platform:da9034-touch");
370 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us