Version:  2.0.40 2.2.26 2.4.37 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 3.17

Linux/drivers/input/touchscreen/wm831x-ts.c

  1 /*
  2  * Touchscreen driver for WM831x PMICs
  3  *
  4  * Copyright 2011 Wolfson Microelectronics plc.
  5  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
  6  *
  7  * This program is free software; you can redistribute  it and/or modify it
  8  * under  the terms of  the GNU General  Public License as published by the
  9  * Free Software Foundation;  either version 2 of the  License, or (at your
 10  * option) any later version.
 11  */
 12 
 13 #include <linux/module.h>
 14 #include <linux/moduleparam.h>
 15 #include <linux/kernel.h>
 16 #include <linux/string.h>
 17 #include <linux/pm.h>
 18 #include <linux/input.h>
 19 #include <linux/interrupt.h>
 20 #include <linux/io.h>
 21 #include <linux/mfd/wm831x/core.h>
 22 #include <linux/mfd/wm831x/irq.h>
 23 #include <linux/mfd/wm831x/pdata.h>
 24 #include <linux/platform_device.h>
 25 #include <linux/slab.h>
 26 #include <linux/types.h>
 27 
 28 /*
 29  * R16424 (0x4028) - Touch Control 1
 30  */
 31 #define WM831X_TCH_ENA                          0x8000  /* TCH_ENA */
 32 #define WM831X_TCH_CVT_ENA                      0x4000  /* TCH_CVT_ENA */
 33 #define WM831X_TCH_SLPENA                       0x1000  /* TCH_SLPENA */
 34 #define WM831X_TCH_Z_ENA                        0x0400  /* TCH_Z_ENA */
 35 #define WM831X_TCH_Y_ENA                        0x0200  /* TCH_Y_ENA */
 36 #define WM831X_TCH_X_ENA                        0x0100  /* TCH_X_ENA */
 37 #define WM831X_TCH_DELAY_MASK                   0x00E0  /* TCH_DELAY - [7:5] */
 38 #define WM831X_TCH_DELAY_SHIFT                       5  /* TCH_DELAY - [7:5] */
 39 #define WM831X_TCH_DELAY_WIDTH                       3  /* TCH_DELAY - [7:5] */
 40 #define WM831X_TCH_RATE_MASK                    0x001F  /* TCH_RATE - [4:0] */
 41 #define WM831X_TCH_RATE_SHIFT                        0  /* TCH_RATE - [4:0] */
 42 #define WM831X_TCH_RATE_WIDTH                        5  /* TCH_RATE - [4:0] */
 43 
 44 /*
 45  * R16425 (0x4029) - Touch Control 2
 46  */
 47 #define WM831X_TCH_PD_WK                        0x2000  /* TCH_PD_WK */
 48 #define WM831X_TCH_5WIRE                        0x1000  /* TCH_5WIRE */
 49 #define WM831X_TCH_PDONLY                       0x0800  /* TCH_PDONLY */
 50 #define WM831X_TCH_ISEL                         0x0100  /* TCH_ISEL */
 51 #define WM831X_TCH_RPU_MASK                     0x000F  /* TCH_RPU - [3:0] */
 52 #define WM831X_TCH_RPU_SHIFT                         0  /* TCH_RPU - [3:0] */
 53 #define WM831X_TCH_RPU_WIDTH                         4  /* TCH_RPU - [3:0] */
 54 
 55 /*
 56  * R16426-8 (0x402A-C) - Touch Data X/Y/X
 57  */
 58 #define WM831X_TCH_PD                           0x8000  /* TCH_PD1 */
 59 #define WM831X_TCH_DATA_MASK                    0x0FFF  /* TCH_DATA - [11:0] */
 60 #define WM831X_TCH_DATA_SHIFT                        0  /* TCH_DATA - [11:0] */
 61 #define WM831X_TCH_DATA_WIDTH                       12  /* TCH_DATA - [11:0] */
 62 
 63 struct wm831x_ts {
 64         struct input_dev *input_dev;
 65         struct wm831x *wm831x;
 66         unsigned int data_irq;
 67         unsigned int pd_irq;
 68         bool pressure;
 69         bool pen_down;
 70         struct work_struct pd_data_work;
 71 };
 72 
 73 static void wm831x_pd_data_work(struct work_struct *work)
 74 {
 75         struct wm831x_ts *wm831x_ts =
 76                 container_of(work, struct wm831x_ts, pd_data_work);
 77 
 78         if (wm831x_ts->pen_down) {
 79                 enable_irq(wm831x_ts->data_irq);
 80                 dev_dbg(wm831x_ts->wm831x->dev, "IRQ PD->DATA done\n");
 81         } else {
 82                 enable_irq(wm831x_ts->pd_irq);
 83                 dev_dbg(wm831x_ts->wm831x->dev, "IRQ DATA->PD done\n");
 84         }
 85 }
 86 
 87 static irqreturn_t wm831x_ts_data_irq(int irq, void *irq_data)
 88 {
 89         struct wm831x_ts *wm831x_ts = irq_data;
 90         struct wm831x *wm831x = wm831x_ts->wm831x;
 91         static int data_types[] = { ABS_X, ABS_Y, ABS_PRESSURE };
 92         u16 data[3];
 93         int count;
 94         int i, ret;
 95 
 96         if (wm831x_ts->pressure)
 97                 count = 3;
 98         else
 99                 count = 2;
100 
101         wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
102                         WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT);
103 
104         ret = wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count,
105                                data);
106         if (ret != 0) {
107                 dev_err(wm831x->dev, "Failed to read touch data: %d\n",
108                         ret);
109                 return IRQ_NONE;
110         }
111 
112         /*
113          * We get a pen down reading on every reading, report pen up if any
114          * individual reading does so.
115          */
116         wm831x_ts->pen_down = true;
117         for (i = 0; i < count; i++) {
118                 if (!(data[i] & WM831X_TCH_PD)) {
119                         wm831x_ts->pen_down = false;
120                         continue;
121                 }
122                 input_report_abs(wm831x_ts->input_dev, data_types[i],
123                                  data[i] & WM831X_TCH_DATA_MASK);
124         }
125 
126         if (!wm831x_ts->pen_down) {
127                 /* Switch from data to pen down */
128                 dev_dbg(wm831x->dev, "IRQ DATA->PD\n");
129 
130                 disable_irq_nosync(wm831x_ts->data_irq);
131 
132                 /* Don't need data any more */
133                 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
134                                 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA |
135                                 WM831X_TCH_Z_ENA, 0);
136 
137                 /* Flush any final samples that arrived while reading */
138                 wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
139                                 WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT);
140 
141                 wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count, data);
142 
143                 if (wm831x_ts->pressure)
144                         input_report_abs(wm831x_ts->input_dev,
145                                          ABS_PRESSURE, 0);
146 
147                 input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 0);
148 
149                 schedule_work(&wm831x_ts->pd_data_work);
150         } else {
151                 input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 1);
152         }
153 
154         input_sync(wm831x_ts->input_dev);
155 
156         return IRQ_HANDLED;
157 }
158 
159 static irqreturn_t wm831x_ts_pen_down_irq(int irq, void *irq_data)
160 {
161         struct wm831x_ts *wm831x_ts = irq_data;
162         struct wm831x *wm831x = wm831x_ts->wm831x;
163         int ena = 0;
164 
165         if (wm831x_ts->pen_down)
166                 return IRQ_HANDLED;
167 
168         disable_irq_nosync(wm831x_ts->pd_irq);
169 
170         /* Start collecting data */
171         if (wm831x_ts->pressure)
172                 ena |= WM831X_TCH_Z_ENA;
173 
174         wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
175                         WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA,
176                         WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | ena);
177 
178         wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1,
179                         WM831X_TCHPD_EINT, WM831X_TCHPD_EINT);
180 
181         wm831x_ts->pen_down = true;
182 
183         /* Switch from pen down to data */
184         dev_dbg(wm831x->dev, "IRQ PD->DATA\n");
185         schedule_work(&wm831x_ts->pd_data_work);
186 
187         return IRQ_HANDLED;
188 }
189 
190 static int wm831x_ts_input_open(struct input_dev *idev)
191 {
192         struct wm831x_ts *wm831x_ts = input_get_drvdata(idev);
193         struct wm831x *wm831x = wm831x_ts->wm831x;
194 
195         wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
196                         WM831X_TCH_ENA | WM831X_TCH_CVT_ENA |
197                         WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA |
198                         WM831X_TCH_Z_ENA, WM831X_TCH_ENA);
199 
200         wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
201                         WM831X_TCH_CVT_ENA, WM831X_TCH_CVT_ENA);
202 
203         return 0;
204 }
205 
206 static void wm831x_ts_input_close(struct input_dev *idev)
207 {
208         struct wm831x_ts *wm831x_ts = input_get_drvdata(idev);
209         struct wm831x *wm831x = wm831x_ts->wm831x;
210 
211         /* Shut the controller down, disabling all other functionality too */
212         wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
213                         WM831X_TCH_ENA | WM831X_TCH_X_ENA |
214                         WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA, 0);
215 
216         /* Make sure any pending IRQs are done, the above will prevent
217          * new ones firing.
218          */
219         synchronize_irq(wm831x_ts->data_irq);
220         synchronize_irq(wm831x_ts->pd_irq);
221 
222         /* Make sure the IRQ completion work is quiesced */
223         flush_work(&wm831x_ts->pd_data_work);
224 
225         /* If we ended up with the pen down then make sure we revert back
226          * to pen detection state for the next time we start up.
227          */
228         if (wm831x_ts->pen_down) {
229                 disable_irq(wm831x_ts->data_irq);
230                 enable_irq(wm831x_ts->pd_irq);
231                 wm831x_ts->pen_down = false;
232         }
233 }
234 
235 static int wm831x_ts_probe(struct platform_device *pdev)
236 {
237         struct wm831x_ts *wm831x_ts;
238         struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
239         struct wm831x_pdata *core_pdata = dev_get_platdata(pdev->dev.parent);
240         struct wm831x_touch_pdata *pdata = NULL;
241         struct input_dev *input_dev;
242         int error, irqf;
243 
244         if (core_pdata)
245                 pdata = core_pdata->touch;
246 
247         wm831x_ts = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_ts),
248                                  GFP_KERNEL);
249         input_dev = devm_input_allocate_device(&pdev->dev);
250         if (!wm831x_ts || !input_dev) {
251                 error = -ENOMEM;
252                 goto err_alloc;
253         }
254 
255         wm831x_ts->wm831x = wm831x;
256         wm831x_ts->input_dev = input_dev;
257         INIT_WORK(&wm831x_ts->pd_data_work, wm831x_pd_data_work);
258 
259         /*
260          * If we have a direct IRQ use it, otherwise use the interrupt
261          * from the WM831x IRQ controller.
262          */
263         wm831x_ts->data_irq = wm831x_irq(wm831x,
264                                          platform_get_irq_byname(pdev,
265                                                                  "TCHDATA"));
266         if (pdata && pdata->data_irq)
267                 wm831x_ts->data_irq = pdata->data_irq;
268 
269         wm831x_ts->pd_irq = wm831x_irq(wm831x,
270                                        platform_get_irq_byname(pdev, "TCHPD"));
271         if (pdata && pdata->pd_irq)
272                 wm831x_ts->pd_irq = pdata->pd_irq;
273 
274         if (pdata)
275                 wm831x_ts->pressure = pdata->pressure;
276         else
277                 wm831x_ts->pressure = true;
278 
279         /* Five wire touchscreens can't report pressure */
280         if (pdata && pdata->fivewire) {
281                 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
282                                 WM831X_TCH_5WIRE, WM831X_TCH_5WIRE);
283 
284                 /* Pressure measurements are not possible for five wire mode */
285                 WARN_ON(pdata->pressure && pdata->fivewire);
286                 wm831x_ts->pressure = false;
287         } else {
288                 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
289                                 WM831X_TCH_5WIRE, 0);
290         }
291 
292         if (pdata) {
293                 switch (pdata->isel) {
294                 default:
295                         dev_err(&pdev->dev, "Unsupported ISEL setting: %d\n",
296                                 pdata->isel);
297                         /* Fall through */
298                 case 200:
299                 case 0:
300                         wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
301                                         WM831X_TCH_ISEL, 0);
302                         break;
303                 case 400:
304                         wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
305                                         WM831X_TCH_ISEL, WM831X_TCH_ISEL);
306                         break;
307                 }
308         }
309 
310         wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2,
311                         WM831X_TCH_PDONLY, 0);
312 
313         /* Default to 96 samples/sec */
314         wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1,
315                         WM831X_TCH_RATE_MASK, 6);
316 
317         if (pdata && pdata->data_irqf)
318                 irqf = pdata->data_irqf;
319         else
320                 irqf = IRQF_TRIGGER_HIGH;
321 
322         error = request_threaded_irq(wm831x_ts->data_irq,
323                                      NULL, wm831x_ts_data_irq,
324                                      irqf | IRQF_ONESHOT,
325                                      "Touchscreen data", wm831x_ts);
326         if (error) {
327                 dev_err(&pdev->dev, "Failed to request data IRQ %d: %d\n",
328                         wm831x_ts->data_irq, error);
329                 goto err_alloc;
330         }
331         disable_irq(wm831x_ts->data_irq);
332 
333         if (pdata && pdata->pd_irqf)
334                 irqf = pdata->pd_irqf;
335         else
336                 irqf = IRQF_TRIGGER_HIGH;
337 
338         error = request_threaded_irq(wm831x_ts->pd_irq,
339                                      NULL, wm831x_ts_pen_down_irq,
340                                      irqf | IRQF_ONESHOT,
341                                      "Touchscreen pen down", wm831x_ts);
342         if (error) {
343                 dev_err(&pdev->dev, "Failed to request pen down IRQ %d: %d\n",
344                         wm831x_ts->pd_irq, error);
345                 goto err_data_irq;
346         }
347 
348         /* set up touch configuration */
349         input_dev->name = "WM831x touchscreen";
350         input_dev->phys = "wm831x";
351         input_dev->open = wm831x_ts_input_open;
352         input_dev->close = wm831x_ts_input_close;
353 
354         __set_bit(EV_ABS, input_dev->evbit);
355         __set_bit(EV_KEY, input_dev->evbit);
356         __set_bit(BTN_TOUCH, input_dev->keybit);
357 
358         input_set_abs_params(input_dev, ABS_X, 0, 4095, 5, 0);
359         input_set_abs_params(input_dev, ABS_Y, 0, 4095, 5, 0);
360         if (wm831x_ts->pressure)
361                 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 4095, 5, 0);
362 
363         input_set_drvdata(input_dev, wm831x_ts);
364         input_dev->dev.parent = &pdev->dev;
365 
366         error = input_register_device(input_dev);
367         if (error)
368                 goto err_pd_irq;
369 
370         platform_set_drvdata(pdev, wm831x_ts);
371         return 0;
372 
373 err_pd_irq:
374         free_irq(wm831x_ts->pd_irq, wm831x_ts);
375 err_data_irq:
376         free_irq(wm831x_ts->data_irq, wm831x_ts);
377 err_alloc:
378 
379         return error;
380 }
381 
382 static int wm831x_ts_remove(struct platform_device *pdev)
383 {
384         struct wm831x_ts *wm831x_ts = platform_get_drvdata(pdev);
385 
386         free_irq(wm831x_ts->pd_irq, wm831x_ts);
387         free_irq(wm831x_ts->data_irq, wm831x_ts);
388 
389         return 0;
390 }
391 
392 static struct platform_driver wm831x_ts_driver = {
393         .driver = {
394                 .name = "wm831x-touch",
395                 .owner = THIS_MODULE,
396         },
397         .probe = wm831x_ts_probe,
398         .remove = wm831x_ts_remove,
399 };
400 module_platform_driver(wm831x_ts_driver);
401 
402 /* Module information */
403 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
404 MODULE_DESCRIPTION("WM831x PMIC touchscreen driver");
405 MODULE_LICENSE("GPL");
406 MODULE_ALIAS("platform:wm831x-touch");
407 

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