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1 | /* |
2 | * Copyright (C) 2008 Michael Hennerich, Analog Devices Inc. | |
3 | * | |
4 | * Description: AD7879 based touchscreen, and GPIO driver (I2C/SPI Interface) | |
5 | * | |
6 | * Bugs: Enter bugs at http://blackfin.uclinux.org/ | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License as published by | |
10 | * the Free Software Foundation; either version 2 of the License, or | |
11 | * (at your option) any later version. | |
12 | * | |
13 | * This program is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | * GNU General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU General Public License | |
19 | * along with this program; if not, see the file COPYING, or write | |
20 | * to the Free Software Foundation, Inc., | |
21 | * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
22 | * | |
23 | * History: | |
24 | * Copyright (c) 2005 David Brownell | |
25 | * Copyright (c) 2006 Nokia Corporation | |
26 | * Various changes: Imre Deak <imre.deak@nokia.com> | |
27 | * | |
28 | * Using code from: | |
29 | * - corgi_ts.c | |
30 | * Copyright (C) 2004-2005 Richard Purdie | |
31 | * - omap_ts.[hc], ads7846.h, ts_osk.c | |
32 | * Copyright (C) 2002 MontaVista Software | |
33 | * Copyright (C) 2004 Texas Instruments | |
34 | * Copyright (C) 2005 Dirk Behme | |
35 | * - ad7877.c | |
36 | * Copyright (C) 2006-2008 Analog Devices Inc. | |
37 | */ | |
38 | ||
39 | #include <linux/device.h> | |
40 | #include <linux/init.h> | |
41 | #include <linux/delay.h> | |
42 | #include <linux/input.h> | |
43 | #include <linux/interrupt.h> | |
44 | #include <linux/irq.h> | |
45 | #include <linux/slab.h> | |
46 | #include <linux/workqueue.h> | |
47 | #include <linux/spi/spi.h> | |
48 | #include <linux/i2c.h> | |
49 | ||
50 | #include <linux/spi/ad7879.h> | |
51 | ||
52 | #define AD7879_REG_ZEROS 0 | |
53 | #define AD7879_REG_CTRL1 1 | |
54 | #define AD7879_REG_CTRL2 2 | |
55 | #define AD7879_REG_CTRL3 3 | |
56 | #define AD7879_REG_AUX1HIGH 4 | |
57 | #define AD7879_REG_AUX1LOW 5 | |
58 | #define AD7879_REG_TEMP1HIGH 6 | |
59 | #define AD7879_REG_TEMP1LOW 7 | |
60 | #define AD7879_REG_XPLUS 8 | |
61 | #define AD7879_REG_YPLUS 9 | |
62 | #define AD7879_REG_Z1 10 | |
63 | #define AD7879_REG_Z2 11 | |
64 | #define AD7879_REG_AUXVBAT 12 | |
65 | #define AD7879_REG_TEMP 13 | |
66 | #define AD7879_REG_REVID 14 | |
67 | ||
68 | /* Control REG 1 */ | |
69 | #define AD7879_TMR(x) ((x & 0xFF) << 0) | |
70 | #define AD7879_ACQ(x) ((x & 0x3) << 8) | |
71 | #define AD7879_MODE_NOC (0 << 10) /* Do not convert */ | |
72 | #define AD7879_MODE_SCC (1 << 10) /* Single channel conversion */ | |
73 | #define AD7879_MODE_SEQ0 (2 << 10) /* Sequence 0 in Slave Mode */ | |
74 | #define AD7879_MODE_SEQ1 (3 << 10) /* Sequence 1 in Master Mode */ | |
75 | #define AD7879_MODE_INT (1 << 15) /* PENIRQ disabled INT enabled */ | |
76 | ||
77 | /* Control REG 2 */ | |
78 | #define AD7879_FCD(x) ((x & 0x3) << 0) | |
79 | #define AD7879_RESET (1 << 4) | |
80 | #define AD7879_MFS(x) ((x & 0x3) << 5) | |
81 | #define AD7879_AVG(x) ((x & 0x3) << 7) | |
82 | #define AD7879_SER (1 << 9) /* non-differential */ | |
83 | #define AD7879_DFR (0 << 9) /* differential */ | |
84 | #define AD7879_GPIOPOL (1 << 10) | |
85 | #define AD7879_GPIODIR (1 << 11) | |
86 | #define AD7879_GPIO_DATA (1 << 12) | |
87 | #define AD7879_GPIO_EN (1 << 13) | |
88 | #define AD7879_PM(x) ((x & 0x3) << 14) | |
89 | #define AD7879_PM_SHUTDOWN (0) | |
90 | #define AD7879_PM_DYN (1) | |
91 | #define AD7879_PM_FULLON (2) | |
92 | ||
93 | /* Control REG 3 */ | |
94 | #define AD7879_TEMPMASK_BIT (1<<15) | |
95 | #define AD7879_AUXVBATMASK_BIT (1<<14) | |
96 | #define AD7879_INTMODE_BIT (1<<13) | |
97 | #define AD7879_GPIOALERTMASK_BIT (1<<12) | |
98 | #define AD7879_AUXLOW_BIT (1<<11) | |
99 | #define AD7879_AUXHIGH_BIT (1<<10) | |
100 | #define AD7879_TEMPLOW_BIT (1<<9) | |
101 | #define AD7879_TEMPHIGH_BIT (1<<8) | |
102 | #define AD7879_YPLUS_BIT (1<<7) | |
103 | #define AD7879_XPLUS_BIT (1<<6) | |
104 | #define AD7879_Z1_BIT (1<<5) | |
105 | #define AD7879_Z2_BIT (1<<4) | |
106 | #define AD7879_AUX_BIT (1<<3) | |
107 | #define AD7879_VBAT_BIT (1<<2) | |
108 | #define AD7879_TEMP_BIT (1<<1) | |
109 | ||
110 | enum { | |
111 | AD7879_SEQ_XPOS = 0, | |
112 | AD7879_SEQ_YPOS = 1, | |
113 | AD7879_SEQ_Z1 = 2, | |
114 | AD7879_SEQ_Z2 = 3, | |
115 | AD7879_NR_SENSE = 4, | |
116 | }; | |
117 | ||
118 | #define MAX_12BIT ((1<<12)-1) | |
119 | #define TS_PEN_UP_TIMEOUT msecs_to_jiffies(50) | |
120 | ||
121 | #if defined(CONFIG_TOUCHSCREEN_AD7879_SPI) || defined(CONFIG_TOUCHSCREEN_AD7879_SPI_MODULE) | |
122 | #define AD7879_DEVID 0x7A | |
123 | typedef struct spi_device bus_device; | |
124 | #elif defined(CONFIG_TOUCHSCREEN_AD7879_I2C) || defined(CONFIG_TOUCHSCREEN_AD7879_I2C_MODULE) | |
125 | #define AD7879_DEVID 0x79 | |
126 | typedef struct i2c_client bus_device; | |
127 | #endif | |
128 | ||
129 | struct ad7879 { | |
130 | bus_device *bus; | |
131 | struct input_dev *input; | |
132 | struct work_struct work; | |
133 | struct timer_list timer; | |
134 | ||
135 | struct mutex mutex; | |
136 | unsigned disabled:1; /* P: mutex */ | |
137 | ||
138 | #if defined(CONFIG_TOUCHSCREEN_AD7879_SPI) || defined(CONFIG_TOUCHSCREEN_AD7879_SPI_MODULE) | |
139 | struct spi_message msg; | |
140 | struct spi_transfer xfer[AD7879_NR_SENSE + 1]; | |
141 | u16 cmd; | |
142 | #endif | |
143 | u16 conversion_data[AD7879_NR_SENSE]; | |
144 | char phys[32]; | |
145 | u8 first_conversion_delay; | |
146 | u8 acquisition_time; | |
147 | u8 averaging; | |
148 | u8 pen_down_acc_interval; | |
149 | u8 median; | |
150 | u16 x_plate_ohms; | |
151 | u16 pressure_max; | |
152 | u16 gpio_init; | |
153 | u16 cmd_crtl1; | |
154 | u16 cmd_crtl2; | |
155 | u16 cmd_crtl3; | |
156 | unsigned gpio:1; | |
157 | }; | |
158 | ||
159 | static int ad7879_read(bus_device *, u8); | |
160 | static int ad7879_write(bus_device *, u8, u16); | |
161 | static void ad7879_collect(struct ad7879 *); | |
162 | ||
163 | static void ad7879_report(struct ad7879 *ts) | |
164 | { | |
165 | struct input_dev *input_dev = ts->input; | |
166 | unsigned Rt; | |
167 | u16 x, y, z1, z2; | |
168 | ||
169 | x = ts->conversion_data[AD7879_SEQ_XPOS] & MAX_12BIT; | |
170 | y = ts->conversion_data[AD7879_SEQ_YPOS] & MAX_12BIT; | |
171 | z1 = ts->conversion_data[AD7879_SEQ_Z1] & MAX_12BIT; | |
172 | z2 = ts->conversion_data[AD7879_SEQ_Z2] & MAX_12BIT; | |
173 | ||
174 | /* | |
175 | * The samples processed here are already preprocessed by the AD7879. | |
176 | * The preprocessing function consists of a median and an averaging filter. | |
177 | * The combination of these two techniques provides a robust solution, | |
178 | * discarding the spurious noise in the signal and keeping only the data of interest. | |
179 | * The size of both filters is programmable. (dev.platform_data, see linux/spi/ad7879.h) | |
180 | * Other user-programmable conversion controls include variable acquisition time, | |
181 | * and first conversion delay. Up to 16 averages can be taken per conversion. | |
182 | */ | |
183 | ||
184 | if (likely(x && z1)) { | |
185 | /* compute touch pressure resistance using equation #1 */ | |
186 | Rt = (z2 - z1) * x * ts->x_plate_ohms; | |
187 | Rt /= z1; | |
188 | Rt = (Rt + 2047) >> 12; | |
189 | ||
190 | input_report_abs(input_dev, ABS_X, x); | |
191 | input_report_abs(input_dev, ABS_Y, y); | |
192 | input_report_abs(input_dev, ABS_PRESSURE, Rt); | |
193 | input_sync(input_dev); | |
194 | } | |
195 | } | |
196 | ||
197 | static void ad7879_work(struct work_struct *work) | |
198 | { | |
199 | struct ad7879 *ts = container_of(work, struct ad7879, work); | |
200 | ||
201 | /* use keventd context to read the result registers */ | |
202 | ad7879_collect(ts); | |
203 | ad7879_report(ts); | |
204 | mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT); | |
205 | } | |
206 | ||
207 | static void ad7879_ts_event_release(struct ad7879 *ts) | |
208 | { | |
209 | struct input_dev *input_dev = ts->input; | |
210 | ||
211 | input_report_abs(input_dev, ABS_PRESSURE, 0); | |
212 | input_sync(input_dev); | |
213 | } | |
214 | ||
215 | static void ad7879_timer(unsigned long handle) | |
216 | { | |
217 | struct ad7879 *ts = (void *)handle; | |
218 | ||
219 | ad7879_ts_event_release(ts); | |
220 | } | |
221 | ||
222 | static irqreturn_t ad7879_irq(int irq, void *handle) | |
223 | { | |
224 | struct ad7879 *ts = handle; | |
225 | ||
226 | /* The repeated conversion sequencer controlled by TMR kicked off too fast. | |
227 | * We ignore the last and process the sample sequence currently in the queue. | |
228 | * It can't be older than 9.4ms | |
229 | */ | |
230 | ||
231 | if (!work_pending(&ts->work)) | |
232 | schedule_work(&ts->work); | |
233 | ||
234 | return IRQ_HANDLED; | |
235 | } | |
236 | ||
237 | static void ad7879_setup(struct ad7879 *ts) | |
238 | { | |
239 | ts->cmd_crtl3 = AD7879_YPLUS_BIT | | |
240 | AD7879_XPLUS_BIT | | |
241 | AD7879_Z2_BIT | | |
242 | AD7879_Z1_BIT | | |
243 | AD7879_TEMPMASK_BIT | | |
244 | AD7879_AUXVBATMASK_BIT | | |
245 | AD7879_GPIOALERTMASK_BIT; | |
246 | ||
247 | ts->cmd_crtl2 = AD7879_PM(AD7879_PM_DYN) | AD7879_DFR | | |
248 | AD7879_AVG(ts->averaging) | | |
249 | AD7879_MFS(ts->median) | | |
250 | AD7879_FCD(ts->first_conversion_delay) | | |
251 | ts->gpio_init; | |
252 | ||
253 | ts->cmd_crtl1 = AD7879_MODE_INT | AD7879_MODE_SEQ1 | | |
254 | AD7879_ACQ(ts->acquisition_time) | | |
255 | AD7879_TMR(ts->pen_down_acc_interval); | |
256 | ||
257 | ad7879_write(ts->bus, AD7879_REG_CTRL2, ts->cmd_crtl2); | |
258 | ad7879_write(ts->bus, AD7879_REG_CTRL3, ts->cmd_crtl3); | |
259 | ad7879_write(ts->bus, AD7879_REG_CTRL1, ts->cmd_crtl1); | |
260 | } | |
261 | ||
262 | static void ad7879_disable(struct ad7879 *ts) | |
263 | { | |
264 | mutex_lock(&ts->mutex); | |
265 | ||
266 | if (!ts->disabled) { | |
267 | ||
268 | ts->disabled = 1; | |
269 | disable_irq(ts->bus->irq); | |
270 | ||
271 | cancel_work_sync(&ts->work); | |
272 | ||
273 | if (del_timer_sync(&ts->timer)) | |
274 | ad7879_ts_event_release(ts); | |
275 | ||
276 | ad7879_write(ts->bus, AD7879_REG_CTRL2, | |
277 | AD7879_PM(AD7879_PM_SHUTDOWN)); | |
278 | } | |
279 | ||
280 | mutex_unlock(&ts->mutex); | |
281 | } | |
282 | ||
283 | static void ad7879_enable(struct ad7879 *ts) | |
284 | { | |
285 | mutex_lock(&ts->mutex); | |
286 | ||
287 | if (ts->disabled) { | |
288 | ad7879_setup(ts); | |
289 | ts->disabled = 0; | |
290 | enable_irq(ts->bus->irq); | |
291 | } | |
292 | ||
293 | mutex_unlock(&ts->mutex); | |
294 | } | |
295 | ||
296 | static ssize_t ad7879_disable_show(struct device *dev, | |
297 | struct device_attribute *attr, char *buf) | |
298 | { | |
299 | struct ad7879 *ts = dev_get_drvdata(dev); | |
300 | ||
301 | return sprintf(buf, "%u\n", ts->disabled); | |
302 | } | |
303 | ||
304 | static ssize_t ad7879_disable_store(struct device *dev, | |
305 | struct device_attribute *attr, | |
306 | const char *buf, size_t count) | |
307 | { | |
308 | struct ad7879 *ts = dev_get_drvdata(dev); | |
309 | unsigned long val; | |
310 | int error; | |
311 | ||
312 | error = strict_strtoul(buf, 10, &val); | |
313 | if (error) | |
314 | return error; | |
315 | ||
316 | if (val) | |
317 | ad7879_disable(ts); | |
318 | else | |
319 | ad7879_enable(ts); | |
320 | ||
321 | return count; | |
322 | } | |
323 | ||
324 | static DEVICE_ATTR(disable, 0664, ad7879_disable_show, ad7879_disable_store); | |
325 | ||
326 | static ssize_t ad7879_gpio_show(struct device *dev, | |
327 | struct device_attribute *attr, char *buf) | |
328 | { | |
329 | struct ad7879 *ts = dev_get_drvdata(dev); | |
330 | ||
331 | return sprintf(buf, "%u\n", ts->gpio); | |
332 | } | |
333 | ||
334 | static ssize_t ad7879_gpio_store(struct device *dev, | |
335 | struct device_attribute *attr, | |
336 | const char *buf, size_t count) | |
337 | { | |
338 | struct ad7879 *ts = dev_get_drvdata(dev); | |
339 | unsigned long val; | |
340 | int error; | |
341 | ||
342 | error = strict_strtoul(buf, 10, &val); | |
343 | if (error) | |
344 | return error; | |
345 | ||
346 | mutex_lock(&ts->mutex); | |
347 | ts->gpio = !!val; | |
348 | error = ad7879_write(ts->bus, AD7879_REG_CTRL2, | |
349 | ts->gpio ? | |
350 | ts->cmd_crtl2 & ~AD7879_GPIO_DATA : | |
351 | ts->cmd_crtl2 | AD7879_GPIO_DATA); | |
352 | mutex_unlock(&ts->mutex); | |
353 | ||
354 | return error ? : count; | |
355 | } | |
356 | ||
357 | static DEVICE_ATTR(gpio, 0664, ad7879_gpio_show, ad7879_gpio_store); | |
358 | ||
359 | static struct attribute *ad7879_attributes[] = { | |
360 | &dev_attr_disable.attr, | |
361 | &dev_attr_gpio.attr, | |
362 | NULL | |
363 | }; | |
364 | ||
365 | static const struct attribute_group ad7879_attr_group = { | |
366 | .attrs = ad7879_attributes, | |
367 | }; | |
368 | ||
369 | static int __devinit ad7879_construct(bus_device *bus, struct ad7879 *ts) | |
370 | { | |
371 | struct input_dev *input_dev; | |
372 | struct ad7879_platform_data *pdata = bus->dev.platform_data; | |
373 | int err; | |
374 | u16 revid; | |
375 | ||
376 | if (!bus->irq) { | |
377 | dev_err(&bus->dev, "no IRQ?\n"); | |
378 | return -ENODEV; | |
379 | } | |
380 | ||
381 | if (!pdata) { | |
382 | dev_err(&bus->dev, "no platform data?\n"); | |
383 | return -ENODEV; | |
384 | } | |
385 | ||
386 | input_dev = input_allocate_device(); | |
387 | if (!input_dev) | |
388 | return -ENOMEM; | |
389 | ||
390 | ts->input = input_dev; | |
391 | ||
392 | setup_timer(&ts->timer, ad7879_timer, (unsigned long) ts); | |
393 | INIT_WORK(&ts->work, ad7879_work); | |
394 | mutex_init(&ts->mutex); | |
395 | ||
396 | ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; | |
397 | ts->pressure_max = pdata->pressure_max ? : ~0; | |
398 | ||
399 | ts->first_conversion_delay = pdata->first_conversion_delay; | |
400 | ts->acquisition_time = pdata->acquisition_time; | |
401 | ts->averaging = pdata->averaging; | |
402 | ts->pen_down_acc_interval = pdata->pen_down_acc_interval; | |
403 | ts->median = pdata->median; | |
404 | ||
405 | if (pdata->gpio_output) | |
406 | ts->gpio_init = AD7879_GPIO_EN | | |
407 | (pdata->gpio_default ? 0 : AD7879_GPIO_DATA); | |
408 | else | |
409 | ts->gpio_init = AD7879_GPIO_EN | AD7879_GPIODIR; | |
410 | ||
411 | snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&bus->dev)); | |
412 | ||
413 | input_dev->name = "AD7879 Touchscreen"; | |
414 | input_dev->phys = ts->phys; | |
415 | input_dev->dev.parent = &bus->dev; | |
416 | ||
417 | __set_bit(EV_ABS, input_dev->evbit); | |
418 | __set_bit(ABS_X, input_dev->absbit); | |
419 | __set_bit(ABS_Y, input_dev->absbit); | |
420 | __set_bit(ABS_PRESSURE, input_dev->absbit); | |
421 | ||
422 | input_set_abs_params(input_dev, ABS_X, | |
423 | pdata->x_min ? : 0, | |
424 | pdata->x_max ? : MAX_12BIT, | |
425 | 0, 0); | |
426 | input_set_abs_params(input_dev, ABS_Y, | |
427 | pdata->y_min ? : 0, | |
428 | pdata->y_max ? : MAX_12BIT, | |
429 | 0, 0); | |
430 | input_set_abs_params(input_dev, ABS_PRESSURE, | |
431 | pdata->pressure_min, pdata->pressure_max, 0, 0); | |
432 | ||
433 | err = ad7879_write(bus, AD7879_REG_CTRL2, AD7879_RESET); | |
434 | ||
435 | if (err < 0) { | |
436 | dev_err(&bus->dev, "Failed to write %s\n", input_dev->name); | |
437 | goto err_free_mem; | |
438 | } | |
439 | ||
440 | revid = ad7879_read(bus, AD7879_REG_REVID); | |
441 | ||
442 | if ((revid & 0xFF) != AD7879_DEVID) { | |
443 | dev_err(&bus->dev, "Failed to probe %s\n", input_dev->name); | |
444 | err = -ENODEV; | |
445 | goto err_free_mem; | |
446 | } | |
447 | ||
448 | ad7879_setup(ts); | |
449 | ||
450 | err = request_irq(bus->irq, ad7879_irq, | |
451 | IRQF_TRIGGER_FALLING | IRQF_SAMPLE_RANDOM, | |
452 | bus->dev.driver->name, ts); | |
453 | ||
454 | if (err) { | |
455 | dev_err(&bus->dev, "irq %d busy?\n", bus->irq); | |
456 | goto err_free_mem; | |
457 | } | |
458 | ||
459 | err = sysfs_create_group(&bus->dev.kobj, &ad7879_attr_group); | |
460 | if (err) | |
461 | goto err_free_irq; | |
462 | ||
463 | err = input_register_device(input_dev); | |
464 | if (err) | |
465 | goto err_remove_attr; | |
466 | ||
467 | dev_info(&bus->dev, "Rev.%d touchscreen, irq %d\n", | |
468 | revid >> 8, bus->irq); | |
469 | ||
470 | return 0; | |
471 | ||
472 | err_remove_attr: | |
473 | sysfs_remove_group(&bus->dev.kobj, &ad7879_attr_group); | |
474 | err_free_irq: | |
475 | free_irq(bus->irq, ts); | |
476 | err_free_mem: | |
477 | input_free_device(input_dev); | |
478 | ||
479 | return err; | |
480 | } | |
481 | ||
482 | static int __devexit ad7879_destroy(bus_device *bus, struct ad7879 *ts) | |
483 | { | |
484 | ad7879_disable(ts); | |
485 | sysfs_remove_group(&ts->bus->dev.kobj, &ad7879_attr_group); | |
486 | free_irq(ts->bus->irq, ts); | |
487 | input_unregister_device(ts->input); | |
488 | dev_dbg(&bus->dev, "unregistered touchscreen\n"); | |
489 | ||
490 | return 0; | |
491 | } | |
492 | ||
493 | #ifdef CONFIG_PM | |
494 | static int ad7879_suspend(bus_device *bus, pm_message_t message) | |
495 | { | |
496 | struct ad7879 *ts = dev_get_drvdata(&bus->dev); | |
497 | ||
498 | ad7879_disable(ts); | |
499 | ||
500 | return 0; | |
501 | } | |
502 | ||
503 | static int ad7879_resume(bus_device *bus) | |
504 | { | |
505 | struct ad7879 *ts = dev_get_drvdata(&bus->dev); | |
506 | ||
507 | ad7879_enable(ts); | |
508 | ||
509 | return 0; | |
510 | } | |
511 | #else | |
512 | #define ad7879_suspend NULL | |
513 | #define ad7879_resume NULL | |
514 | #endif | |
515 | ||
516 | #if defined(CONFIG_TOUCHSCREEN_AD7879_SPI) || defined(CONFIG_TOUCHSCREEN_AD7879_SPI_MODULE) | |
517 | #define MAX_SPI_FREQ_HZ 5000000 | |
518 | #define AD7879_CMD_MAGIC 0xE000 | |
519 | #define AD7879_CMD_READ (1 << 10) | |
520 | #define AD7879_WRITECMD(reg) (AD7879_CMD_MAGIC | (reg & 0xF)) | |
521 | #define AD7879_READCMD(reg) (AD7879_CMD_MAGIC | AD7879_CMD_READ | (reg & 0xF)) | |
522 | ||
523 | struct ser_req { | |
524 | u16 command; | |
525 | u16 data; | |
526 | struct spi_message msg; | |
527 | struct spi_transfer xfer[2]; | |
528 | }; | |
529 | ||
530 | /* | |
531 | * ad7879_read/write are only used for initial setup and for sysfs controls. | |
532 | * The main traffic is done in ad7879_collect(). | |
533 | */ | |
534 | ||
535 | static int ad7879_read(struct spi_device *spi, u8 reg) | |
536 | { | |
537 | struct ser_req *req; | |
538 | int status, ret; | |
539 | ||
540 | req = kzalloc(sizeof *req, GFP_KERNEL); | |
541 | if (!req) | |
542 | return -ENOMEM; | |
543 | ||
544 | spi_message_init(&req->msg); | |
545 | ||
546 | req->command = (u16) AD7879_READCMD(reg); | |
547 | req->xfer[0].tx_buf = &req->command; | |
548 | req->xfer[0].len = 2; | |
549 | ||
550 | req->xfer[1].rx_buf = &req->data; | |
551 | req->xfer[1].len = 2; | |
552 | ||
553 | spi_message_add_tail(&req->xfer[0], &req->msg); | |
554 | spi_message_add_tail(&req->xfer[1], &req->msg); | |
555 | ||
556 | status = spi_sync(spi, &req->msg); | |
557 | ret = status ? : req->data; | |
558 | ||
559 | kfree(req); | |
560 | ||
561 | return ret; | |
562 | } | |
563 | ||
564 | static int ad7879_write(struct spi_device *spi, u8 reg, u16 val) | |
565 | { | |
566 | struct ser_req *req; | |
567 | int status; | |
568 | ||
569 | req = kzalloc(sizeof *req, GFP_KERNEL); | |
570 | if (!req) | |
571 | return -ENOMEM; | |
572 | ||
573 | spi_message_init(&req->msg); | |
574 | ||
575 | req->command = (u16) AD7879_WRITECMD(reg); | |
576 | req->xfer[0].tx_buf = &req->command; | |
577 | req->xfer[0].len = 2; | |
578 | ||
579 | req->data = val; | |
580 | req->xfer[1].tx_buf = &req->data; | |
581 | req->xfer[1].len = 2; | |
582 | ||
583 | spi_message_add_tail(&req->xfer[0], &req->msg); | |
584 | spi_message_add_tail(&req->xfer[1], &req->msg); | |
585 | ||
586 | status = spi_sync(spi, &req->msg); | |
587 | ||
588 | kfree(req); | |
589 | ||
590 | return status; | |
591 | } | |
592 | ||
593 | static void ad7879_collect(struct ad7879 *ts) | |
594 | { | |
595 | int status = spi_sync(ts->bus, &ts->msg); | |
596 | ||
597 | if (status) | |
598 | dev_err(&ts->bus->dev, "spi_sync --> %d\n", status); | |
599 | } | |
600 | ||
601 | static void ad7879_setup_ts_def_msg(struct ad7879 *ts) | |
602 | { | |
603 | struct spi_message *m; | |
604 | int i; | |
605 | ||
606 | ts->cmd = (u16) AD7879_READCMD(AD7879_REG_XPLUS); | |
607 | ||
608 | m = &ts->msg; | |
609 | spi_message_init(m); | |
610 | ts->xfer[0].tx_buf = &ts->cmd; | |
611 | ts->xfer[0].len = 2; | |
612 | ||
613 | spi_message_add_tail(&ts->xfer[0], m); | |
614 | ||
615 | for (i = 0; i < AD7879_NR_SENSE; i++) { | |
616 | ts->xfer[i + 1].rx_buf = &ts->conversion_data[i]; | |
617 | ts->xfer[i + 1].len = 2; | |
618 | spi_message_add_tail(&ts->xfer[i + 1], m); | |
619 | } | |
620 | } | |
621 | ||
622 | static int __devinit ad7879_probe(struct spi_device *spi) | |
623 | { | |
624 | struct ad7879 *ts; | |
625 | int error; | |
626 | ||
627 | /* don't exceed max specified SPI CLK frequency */ | |
628 | if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) { | |
629 | dev_err(&spi->dev, "SPI CLK %d Hz?\n", spi->max_speed_hz); | |
630 | return -EINVAL; | |
631 | } | |
632 | ||
633 | ts = kzalloc(sizeof(struct ad7879), GFP_KERNEL); | |
634 | if (!ts) | |
635 | return -ENOMEM; | |
636 | ||
637 | dev_set_drvdata(&spi->dev, ts); | |
638 | ts->bus = spi; | |
639 | ||
640 | ad7879_setup_ts_def_msg(ts); | |
641 | ||
642 | error = ad7879_construct(spi, ts); | |
643 | if (error) { | |
644 | dev_set_drvdata(&spi->dev, NULL); | |
645 | kfree(ts); | |
646 | } | |
647 | ||
648 | return 0; | |
649 | } | |
650 | ||
651 | static int __devexit ad7879_remove(struct spi_device *spi) | |
652 | { | |
653 | struct ad7879 *ts = dev_get_drvdata(&spi->dev); | |
654 | ||
655 | ad7879_destroy(spi, ts); | |
656 | dev_set_drvdata(&spi->dev, NULL); | |
657 | kfree(ts); | |
658 | ||
659 | return 0; | |
660 | } | |
661 | ||
662 | static struct spi_driver ad7879_driver = { | |
663 | .driver = { | |
664 | .name = "ad7879", | |
665 | .bus = &spi_bus_type, | |
666 | .owner = THIS_MODULE, | |
667 | }, | |
668 | .probe = ad7879_probe, | |
669 | .remove = __devexit_p(ad7879_remove), | |
670 | .suspend = ad7879_suspend, | |
671 | .resume = ad7879_resume, | |
672 | }; | |
673 | ||
674 | static int __init ad7879_init(void) | |
675 | { | |
676 | return spi_register_driver(&ad7879_driver); | |
677 | } | |
678 | module_init(ad7879_init); | |
679 | ||
680 | static void __exit ad7879_exit(void) | |
681 | { | |
682 | spi_unregister_driver(&ad7879_driver); | |
683 | } | |
684 | module_exit(ad7879_exit); | |
685 | ||
686 | #elif defined(CONFIG_TOUCHSCREEN_AD7879_I2C) || defined(CONFIG_TOUCHSCREEN_AD7879_I2C_MODULE) | |
687 | ||
688 | /* All registers are word-sized. | |
689 | * AD7879 uses a high-byte first convention. | |
690 | */ | |
691 | static int ad7879_read(struct i2c_client *client, u8 reg) | |
692 | { | |
693 | return swab16(i2c_smbus_read_word_data(client, reg)); | |
694 | } | |
695 | ||
696 | static int ad7879_write(struct i2c_client *client, u8 reg, u16 val) | |
697 | { | |
698 | return i2c_smbus_write_word_data(client, reg, swab16(val)); | |
699 | } | |
700 | ||
701 | static void ad7879_collect(struct ad7879 *ts) | |
702 | { | |
703 | int i; | |
704 | ||
705 | for (i = 0; i < AD7879_NR_SENSE; i++) | |
706 | ts->conversion_data[i] = ad7879_read(ts->bus, | |
707 | AD7879_REG_XPLUS + i); | |
708 | } | |
709 | ||
710 | static int __devinit ad7879_probe(struct i2c_client *client, | |
711 | const struct i2c_device_id *id) | |
712 | { | |
713 | struct ad7879 *ts; | |
714 | int error; | |
715 | ||
716 | if (!i2c_check_functionality(client->adapter, | |
717 | I2C_FUNC_SMBUS_WORD_DATA)) { | |
718 | dev_err(&client->dev, "SMBUS Word Data not Supported\n"); | |
719 | return -EIO; | |
720 | } | |
721 | ||
722 | ts = kzalloc(sizeof(struct ad7879), GFP_KERNEL); | |
723 | if (!ts) | |
724 | return -ENOMEM; | |
725 | ||
726 | i2c_set_clientdata(client, ts); | |
727 | ts->bus = client; | |
728 | ||
729 | error = ad7879_construct(client, ts); | |
730 | if (error) { | |
731 | i2c_set_clientdata(client, NULL); | |
732 | kfree(ts); | |
733 | } | |
734 | ||
735 | return 0; | |
736 | } | |
737 | ||
738 | static int __devexit ad7879_remove(struct i2c_client *client) | |
739 | { | |
740 | struct ad7879 *ts = dev_get_drvdata(&client->dev); | |
741 | ||
742 | ad7879_destroy(client, ts); | |
743 | i2c_set_clientdata(client, NULL); | |
744 | kfree(ts); | |
745 | ||
746 | return 0; | |
747 | } | |
748 | ||
749 | static const struct i2c_device_id ad7879_id[] = { | |
750 | { "ad7879", 0 }, | |
751 | { } | |
752 | }; | |
753 | MODULE_DEVICE_TABLE(i2c, ad7879_id); | |
754 | ||
755 | static struct i2c_driver ad7879_driver = { | |
756 | .driver = { | |
757 | .name = "ad7879", | |
758 | .owner = THIS_MODULE, | |
759 | }, | |
760 | .probe = ad7879_probe, | |
761 | .remove = __devexit_p(ad7879_remove), | |
762 | .suspend = ad7879_suspend, | |
763 | .resume = ad7879_resume, | |
764 | .id_table = ad7879_id, | |
765 | }; | |
766 | ||
767 | static int __init ad7879_init(void) | |
768 | { | |
769 | return i2c_add_driver(&ad7879_driver); | |
770 | } | |
771 | module_init(ad7879_init); | |
772 | ||
773 | static void __exit ad7879_exit(void) | |
774 | { | |
775 | i2c_del_driver(&ad7879_driver); | |
776 | } | |
777 | module_exit(ad7879_exit); | |
778 | #endif | |
779 | ||
780 | MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); | |
781 | MODULE_DESCRIPTION("AD7879(-1) touchscreen Driver"); | |
782 | MODULE_LICENSE("GPL"); |