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/atmel-wm97xx.c

  1 /*
  2  * Atmel AT91 and AVR32 continuous touch screen driver for Wolfson WM97xx AC97
  3  * codecs.
  4  *
  5  * Copyright (C) 2008 - 2009 Atmel Corporation
  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 version 2 as published by
  9  * the Free Software Foundation.
 10  */
 11 #include <linux/module.h>
 12 #include <linux/moduleparam.h>
 13 #include <linux/kernel.h>
 14 #include <linux/init.h>
 15 #include <linux/delay.h>
 16 #include <linux/irq.h>
 17 #include <linux/interrupt.h>
 18 #include <linux/wm97xx.h>
 19 #include <linux/timer.h>
 20 #include <linux/gpio.h>
 21 #include <linux/io.h>
 22 #include <linux/slab.h>
 23 
 24 #define AC97C_ICA               0x10
 25 #define AC97C_CBRHR             0x30
 26 #define AC97C_CBSR              0x38
 27 #define AC97C_CBMR              0x3c
 28 #define AC97C_IER               0x54
 29 #define AC97C_IDR               0x58
 30 
 31 #define AC97C_RXRDY             (1 << 4)
 32 #define AC97C_OVRUN             (1 << 5)
 33 
 34 #define AC97C_CMR_SIZE_20       (0 << 16)
 35 #define AC97C_CMR_SIZE_18       (1 << 16)
 36 #define AC97C_CMR_SIZE_16       (2 << 16)
 37 #define AC97C_CMR_SIZE_10       (3 << 16)
 38 #define AC97C_CMR_CEM_LITTLE    (1 << 18)
 39 #define AC97C_CMR_CEM_BIG       (0 << 18)
 40 #define AC97C_CMR_CENA          (1 << 21)
 41 
 42 #define AC97C_INT_CBEVT         (1 << 4)
 43 
 44 #define AC97C_SR_CAEVT          (1 << 3)
 45 
 46 #define AC97C_CH_MASK(slot)                                             \
 47         (0x7 << (3 * (slot - 3)))
 48 #define AC97C_CH_ASSIGN(slot, channel)                                  \
 49         (AC97C_CHANNEL_##channel << (3 * (slot - 3)))
 50 #define AC97C_CHANNEL_NONE      0x0
 51 #define AC97C_CHANNEL_B         0x2
 52 
 53 #define ac97c_writel(chip, reg, val)                    \
 54         __raw_writel((val), (chip)->regs + AC97C_##reg)
 55 #define ac97c_readl(chip, reg)                          \
 56         __raw_readl((chip)->regs + AC97C_##reg)
 57 
 58 #ifdef CONFIG_CPU_AT32AP700X
 59 #define ATMEL_WM97XX_AC97C_IOMEM        (0xfff02800)
 60 #define ATMEL_WM97XX_AC97C_IRQ          (29)
 61 #define ATMEL_WM97XX_GPIO_DEFAULT       (32+16) /* Pin 16 on port B. */
 62 #else
 63 #error Unknown CPU, this driver only supports AT32AP700X CPUs.
 64 #endif
 65 
 66 struct continuous {
 67         u16 id;    /* codec id */
 68         u8 code;   /* continuous code */
 69         u8 reads;  /* number of coord reads per read cycle */
 70         u32 speed; /* number of coords per second */
 71 };
 72 
 73 #define WM_READS(sp) ((sp / HZ) + 1)
 74 
 75 static const struct continuous cinfo[] = {
 76         {WM9705_ID2, 0, WM_READS(94), 94},
 77         {WM9705_ID2, 1, WM_READS(188), 188},
 78         {WM9705_ID2, 2, WM_READS(375), 375},
 79         {WM9705_ID2, 3, WM_READS(750), 750},
 80         {WM9712_ID2, 0, WM_READS(94), 94},
 81         {WM9712_ID2, 1, WM_READS(188), 188},
 82         {WM9712_ID2, 2, WM_READS(375), 375},
 83         {WM9712_ID2, 3, WM_READS(750), 750},
 84         {WM9713_ID2, 0, WM_READS(94), 94},
 85         {WM9713_ID2, 1, WM_READS(120), 120},
 86         {WM9713_ID2, 2, WM_READS(154), 154},
 87         {WM9713_ID2, 3, WM_READS(188), 188},
 88 };
 89 
 90 /* Continuous speed index. */
 91 static int sp_idx;
 92 
 93 /*
 94  * Pen sampling frequency (Hz) in continuous mode.
 95  */
 96 static int cont_rate = 188;
 97 module_param(cont_rate, int, 0);
 98 MODULE_PARM_DESC(cont_rate, "Sampling rate in continuous mode (Hz)");
 99 
100 /*
101  * Pen down detection.
102  *
103  * This driver can either poll or use an interrupt to indicate a pen down
104  * event. If the irq request fails then it will fall back to polling mode.
105  */
106 static int pen_int = 1;
107 module_param(pen_int, int, 0);
108 MODULE_PARM_DESC(pen_int, "Pen down detection (1 = interrupt, 0 = polling)");
109 
110 /*
111  * Pressure readback.
112  *
113  * Set to 1 to read back pen down pressure.
114  */
115 static int pressure;
116 module_param(pressure, int, 0);
117 MODULE_PARM_DESC(pressure, "Pressure readback (1 = pressure, 0 = no pressure)");
118 
119 /*
120  * AC97 touch data slot.
121  *
122  * Touch screen readback data ac97 slot.
123  */
124 static int ac97_touch_slot = 5;
125 module_param(ac97_touch_slot, int, 0);
126 MODULE_PARM_DESC(ac97_touch_slot, "Touch screen data slot AC97 number");
127 
128 /*
129  * GPIO line number.
130  *
131  * Set to GPIO number where the signal from the WM97xx device is hooked up.
132  */
133 static int atmel_gpio_line = ATMEL_WM97XX_GPIO_DEFAULT;
134 module_param(atmel_gpio_line, int, 0);
135 MODULE_PARM_DESC(atmel_gpio_line, "GPIO line number connected to WM97xx");
136 
137 struct atmel_wm97xx {
138         struct wm97xx           *wm;
139         struct timer_list       pen_timer;
140         void __iomem            *regs;
141         unsigned long           ac97c_irq;
142         unsigned long           gpio_pen;
143         unsigned long           gpio_irq;
144         unsigned short          x;
145         unsigned short          y;
146 };
147 
148 static irqreturn_t atmel_wm97xx_channel_b_interrupt(int irq, void *dev_id)
149 {
150         struct atmel_wm97xx *atmel_wm97xx = dev_id;
151         struct wm97xx *wm = atmel_wm97xx->wm;
152         int status = ac97c_readl(atmel_wm97xx, CBSR);
153         irqreturn_t retval = IRQ_NONE;
154 
155         if (status & AC97C_OVRUN) {
156                 dev_dbg(&wm->touch_dev->dev, "AC97C overrun\n");
157                 ac97c_readl(atmel_wm97xx, CBRHR);
158                 retval = IRQ_HANDLED;
159         } else if (status & AC97C_RXRDY) {
160                 u16 data;
161                 u16 value;
162                 u16 source;
163                 u16 pen_down;
164 
165                 data = ac97c_readl(atmel_wm97xx, CBRHR);
166                 value = data & 0x0fff;
167                 source = data & WM97XX_ADCSEL_MASK;
168                 pen_down = (data & WM97XX_PEN_DOWN) >> 8;
169 
170                 if (source == WM97XX_ADCSEL_X)
171                         atmel_wm97xx->x = value;
172                 if (source == WM97XX_ADCSEL_Y)
173                         atmel_wm97xx->y = value;
174 
175                 if (!pressure && source == WM97XX_ADCSEL_Y) {
176                         input_report_abs(wm->input_dev, ABS_X, atmel_wm97xx->x);
177                         input_report_abs(wm->input_dev, ABS_Y, atmel_wm97xx->y);
178                         input_report_key(wm->input_dev, BTN_TOUCH, pen_down);
179                         input_sync(wm->input_dev);
180                 } else if (pressure && source == WM97XX_ADCSEL_PRES) {
181                         input_report_abs(wm->input_dev, ABS_X, atmel_wm97xx->x);
182                         input_report_abs(wm->input_dev, ABS_Y, atmel_wm97xx->y);
183                         input_report_abs(wm->input_dev, ABS_PRESSURE, value);
184                         input_report_key(wm->input_dev, BTN_TOUCH, value);
185                         input_sync(wm->input_dev);
186                 }
187 
188                 retval = IRQ_HANDLED;
189         }
190 
191         return retval;
192 }
193 
194 static void atmel_wm97xx_acc_pen_up(struct wm97xx *wm)
195 {
196         struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(wm->touch_dev);
197         struct input_dev *input_dev = wm->input_dev;
198         int pen_down = gpio_get_value(atmel_wm97xx->gpio_pen);
199 
200         if (pen_down != 0) {
201                 mod_timer(&atmel_wm97xx->pen_timer,
202                           jiffies + msecs_to_jiffies(1));
203         } else {
204                 if (pressure)
205                         input_report_abs(input_dev, ABS_PRESSURE, 0);
206                 input_report_key(input_dev, BTN_TOUCH, 0);
207                 input_sync(input_dev);
208         }
209 }
210 
211 static void atmel_wm97xx_pen_timer(unsigned long data)
212 {
213         atmel_wm97xx_acc_pen_up((struct wm97xx *)data);
214 }
215 
216 static int atmel_wm97xx_acc_startup(struct wm97xx *wm)
217 {
218         struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(wm->touch_dev);
219         int idx = 0;
220 
221         if (wm->ac97 == NULL)
222                 return -ENODEV;
223 
224         for (idx = 0; idx < ARRAY_SIZE(cinfo); idx++) {
225                 if (wm->id != cinfo[idx].id)
226                         continue;
227 
228                 sp_idx = idx;
229 
230                 if (cont_rate <= cinfo[idx].speed)
231                         break;
232         }
233 
234         wm->acc_rate = cinfo[sp_idx].code;
235         wm->acc_slot = ac97_touch_slot;
236         dev_info(&wm->touch_dev->dev, "atmel accelerated touchscreen driver, "
237                         "%d samples/sec\n", cinfo[sp_idx].speed);
238 
239         if (pen_int) {
240                 unsigned long reg;
241 
242                 wm->pen_irq = atmel_wm97xx->gpio_irq;
243 
244                 switch (wm->id) {
245                 case WM9712_ID2: /* Fall through. */
246                 case WM9713_ID2:
247                         /*
248                          * Use GPIO 13 (PEN_DOWN) to assert GPIO line 3
249                          * (PENDOWN).
250                          */
251                         wm97xx_config_gpio(wm, WM97XX_GPIO_13, WM97XX_GPIO_IN,
252                                         WM97XX_GPIO_POL_HIGH,
253                                         WM97XX_GPIO_STICKY,
254                                         WM97XX_GPIO_WAKE);
255                         wm97xx_config_gpio(wm, WM97XX_GPIO_3, WM97XX_GPIO_OUT,
256                                         WM97XX_GPIO_POL_HIGH,
257                                         WM97XX_GPIO_NOTSTICKY,
258                                         WM97XX_GPIO_NOWAKE);
259                 case WM9705_ID2: /* Fall through. */
260                         /*
261                          * Enable touch data slot in AC97 controller channel B.
262                          */
263                         reg = ac97c_readl(atmel_wm97xx, ICA);
264                         reg &= ~AC97C_CH_MASK(wm->acc_slot);
265                         reg |= AC97C_CH_ASSIGN(wm->acc_slot, B);
266                         ac97c_writel(atmel_wm97xx, ICA, reg);
267 
268                         /*
269                          * Enable channel and interrupt for RXRDY and OVERRUN.
270                          */
271                         ac97c_writel(atmel_wm97xx, CBMR, AC97C_CMR_CENA
272                                         | AC97C_CMR_CEM_BIG
273                                         | AC97C_CMR_SIZE_16
274                                         | AC97C_OVRUN
275                                         | AC97C_RXRDY);
276                         /* Dummy read to empty RXRHR. */
277                         ac97c_readl(atmel_wm97xx, CBRHR);
278                         /*
279                          * Enable interrupt for channel B in the AC97
280                          * controller.
281                          */
282                         ac97c_writel(atmel_wm97xx, IER, AC97C_INT_CBEVT);
283                         break;
284                 default:
285                         dev_err(&wm->touch_dev->dev, "pen down irq not "
286                                         "supported on this device\n");
287                         pen_int = 0;
288                         break;
289                 }
290         }
291 
292         return 0;
293 }
294 
295 static void atmel_wm97xx_acc_shutdown(struct wm97xx *wm)
296 {
297         if (pen_int) {
298                 struct atmel_wm97xx *atmel_wm97xx =
299                         platform_get_drvdata(wm->touch_dev);
300                 unsigned long ica;
301 
302                 switch (wm->id & 0xffff) {
303                 case WM9705_ID2: /* Fall through. */
304                 case WM9712_ID2: /* Fall through. */
305                 case WM9713_ID2:
306                         /* Disable slot and turn off channel B interrupts. */
307                         ica = ac97c_readl(atmel_wm97xx, ICA);
308                         ica &= ~AC97C_CH_MASK(wm->acc_slot);
309                         ac97c_writel(atmel_wm97xx, ICA, ica);
310                         ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT);
311                         ac97c_writel(atmel_wm97xx, CBMR, 0);
312                         wm->pen_irq = 0;
313                         break;
314                 default:
315                         dev_err(&wm->touch_dev->dev, "unknown codec\n");
316                         break;
317                 }
318         }
319 }
320 
321 static void atmel_wm97xx_irq_enable(struct wm97xx *wm, int enable)
322 {
323         /* Intentionally left empty. */
324 }
325 
326 static struct wm97xx_mach_ops atmel_mach_ops = {
327         .acc_enabled    = 1,
328         .acc_pen_up     = atmel_wm97xx_acc_pen_up,
329         .acc_startup    = atmel_wm97xx_acc_startup,
330         .acc_shutdown   = atmel_wm97xx_acc_shutdown,
331         .irq_enable     = atmel_wm97xx_irq_enable,
332         .irq_gpio       = WM97XX_GPIO_3,
333 };
334 
335 static int __init atmel_wm97xx_probe(struct platform_device *pdev)
336 {
337         struct wm97xx *wm = platform_get_drvdata(pdev);
338         struct atmel_wm97xx *atmel_wm97xx;
339         int ret;
340 
341         atmel_wm97xx = kzalloc(sizeof(struct atmel_wm97xx), GFP_KERNEL);
342         if (!atmel_wm97xx) {
343                 dev_dbg(&pdev->dev, "out of memory\n");
344                 return -ENOMEM;
345         }
346 
347         atmel_wm97xx->wm        = wm;
348         atmel_wm97xx->regs      = (void *)ATMEL_WM97XX_AC97C_IOMEM;
349         atmel_wm97xx->ac97c_irq = ATMEL_WM97XX_AC97C_IRQ;
350         atmel_wm97xx->gpio_pen  = atmel_gpio_line;
351         atmel_wm97xx->gpio_irq  = gpio_to_irq(atmel_wm97xx->gpio_pen);
352 
353         setup_timer(&atmel_wm97xx->pen_timer, atmel_wm97xx_pen_timer,
354                         (unsigned long)wm);
355 
356         ret = request_irq(atmel_wm97xx->ac97c_irq,
357                           atmel_wm97xx_channel_b_interrupt,
358                           IRQF_SHARED, "atmel-wm97xx-ch-b", atmel_wm97xx);
359         if (ret) {
360                 dev_dbg(&pdev->dev, "could not request ac97c irq\n");
361                 goto err;
362         }
363 
364         platform_set_drvdata(pdev, atmel_wm97xx);
365 
366         ret = wm97xx_register_mach_ops(wm, &atmel_mach_ops);
367         if (ret)
368                 goto err_irq;
369 
370         return ret;
371 
372 err_irq:
373         free_irq(atmel_wm97xx->ac97c_irq, atmel_wm97xx);
374 err:
375         kfree(atmel_wm97xx);
376         return ret;
377 }
378 
379 static int __exit atmel_wm97xx_remove(struct platform_device *pdev)
380 {
381         struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev);
382         struct wm97xx *wm = atmel_wm97xx->wm;
383 
384         ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT);
385         free_irq(atmel_wm97xx->ac97c_irq, atmel_wm97xx);
386         del_timer_sync(&atmel_wm97xx->pen_timer);
387         wm97xx_unregister_mach_ops(wm);
388         kfree(atmel_wm97xx);
389 
390         return 0;
391 }
392 
393 #ifdef CONFIG_PM_SLEEP
394 static int atmel_wm97xx_suspend(struct device *dev)
395 {
396         struct platform_device *pdev = to_platform_device(dev);
397         struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev);
398 
399         ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT);
400         disable_irq(atmel_wm97xx->gpio_irq);
401         del_timer_sync(&atmel_wm97xx->pen_timer);
402 
403         return 0;
404 }
405 
406 static int atmel_wm97xx_resume(struct device *dev)
407 {
408         struct platform_device *pdev = to_platform_device(dev);
409         struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev);
410         struct wm97xx *wm = atmel_wm97xx->wm;
411 
412         if (wm->input_dev->users) {
413                 enable_irq(atmel_wm97xx->gpio_irq);
414                 ac97c_writel(atmel_wm97xx, IER, AC97C_INT_CBEVT);
415         }
416 
417         return 0;
418 }
419 #endif
420 
421 static SIMPLE_DEV_PM_OPS(atmel_wm97xx_pm_ops,
422                          atmel_wm97xx_suspend, atmel_wm97xx_resume);
423 
424 static struct platform_driver atmel_wm97xx_driver = {
425         .remove         = __exit_p(atmel_wm97xx_remove),
426         .driver         = {
427                 .name   = "wm97xx-touch",
428                 .owner  = THIS_MODULE,
429                 .pm     = &atmel_wm97xx_pm_ops,
430         },
431 };
432 
433 module_platform_driver_probe(atmel_wm97xx_driver, atmel_wm97xx_probe);
434 
435 MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
436 MODULE_DESCRIPTION("wm97xx continuous touch driver for Atmel AT91 and AVR32");
437 MODULE_LICENSE("GPL");
438 

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