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1/*
2 * drivers/input/touchscreen/tsc2007.c
3 *
4 * Copyright (c) 2008 MtekVision Co., Ltd.
5 * Kwangwoo Lee <kwlee@mtekvision.com>
6 *
7 * Using code from:
8 * - ads7846.c
9 * Copyright (c) 2005 David Brownell
10 * Copyright (c) 2006 Nokia Corporation
11 * - corgi_ts.c
12 * Copyright (C) 2004-2005 Richard Purdie
13 * - omap_ts.[hc], ads7846.h, ts_osk.c
14 * Copyright (C) 2002 MontaVista Software
15 * Copyright (C) 2004 Texas Instruments
16 * Copyright (C) 2005 Dirk Behme
17 *
18 * This program is free software; you can redistribute it and/or modify
19 * it under the terms of the GNU General Public License version 2 as
20 * published by the Free Software Foundation.
21 */
22
23#include <linux/module.h>
24#include <linux/slab.h>
25#include <linux/input.h>
26#include <linux/interrupt.h>
27#include <linux/i2c.h>
28#include <linux/i2c/tsc2007.h>
29#include <linux/of_device.h>
30#include <linux/of.h>
31#include <linux/of_gpio.h>
32
33#define TSC2007_MEASURE_TEMP0 (0x0 << 4)
34#define TSC2007_MEASURE_AUX (0x2 << 4)
35#define TSC2007_MEASURE_TEMP1 (0x4 << 4)
36#define TSC2007_ACTIVATE_XN (0x8 << 4)
37#define TSC2007_ACTIVATE_YN (0x9 << 4)
38#define TSC2007_ACTIVATE_YP_XN (0xa << 4)
39#define TSC2007_SETUP (0xb << 4)
40#define TSC2007_MEASURE_X (0xc << 4)
41#define TSC2007_MEASURE_Y (0xd << 4)
42#define TSC2007_MEASURE_Z1 (0xe << 4)
43#define TSC2007_MEASURE_Z2 (0xf << 4)
44
45#define TSC2007_POWER_OFF_IRQ_EN (0x0 << 2)
46#define TSC2007_ADC_ON_IRQ_DIS0 (0x1 << 2)
47#define TSC2007_ADC_OFF_IRQ_EN (0x2 << 2)
48#define TSC2007_ADC_ON_IRQ_DIS1 (0x3 << 2)
49
50#define TSC2007_12BIT (0x0 << 1)
51#define TSC2007_8BIT (0x1 << 1)
52
53#define MAX_12BIT ((1 << 12) - 1)
54
55#define ADC_ON_12BIT (TSC2007_12BIT | TSC2007_ADC_ON_IRQ_DIS0)
56
57#define READ_Y (ADC_ON_12BIT | TSC2007_MEASURE_Y)
58#define READ_Z1 (ADC_ON_12BIT | TSC2007_MEASURE_Z1)
59#define READ_Z2 (ADC_ON_12BIT | TSC2007_MEASURE_Z2)
60#define READ_X (ADC_ON_12BIT | TSC2007_MEASURE_X)
61#define PWRDOWN (TSC2007_12BIT | TSC2007_POWER_OFF_IRQ_EN)
62
63struct ts_event {
64 u16 x;
65 u16 y;
66 u16 z1, z2;
67};
68
69struct tsc2007 {
70 struct input_dev *input;
71 char phys[32];
72
73 struct i2c_client *client;
74
75 u16 model;
76 u16 x_plate_ohms;
77 u16 max_rt;
78 unsigned long poll_period; /* in jiffies */
79 int fuzzx;
80 int fuzzy;
81 int fuzzz;
82
83 unsigned gpio;
84 int irq;
85
86 wait_queue_head_t wait;
87 bool stopped;
88
89 int (*get_pendown_state)(struct device *);
90 void (*clear_penirq)(void);
91};
92
93static inline int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd)
94{
95 s32 data;
96 u16 val;
97
98 data = i2c_smbus_read_word_data(tsc->client, cmd);
99 if (data < 0) {
100 dev_err(&tsc->client->dev, "i2c io error: %d\n", data);
101 return data;
102 }
103
104 /* The protocol and raw data format from i2c interface:
105 * S Addr Wr [A] Comm [A] S Addr Rd [A] [DataLow] A [DataHigh] NA P
106 * Where DataLow has [D11-D4], DataHigh has [D3-D0 << 4 | Dummy 4bit].
107 */
108 val = swab16(data) >> 4;
109
110 dev_dbg(&tsc->client->dev, "data: 0x%x, val: 0x%x\n", data, val);
111
112 return val;
113}
114
115static void tsc2007_read_values(struct tsc2007 *tsc, struct ts_event *tc)
116{
117 /* y- still on; turn on only y+ (and ADC) */
118 tc->y = tsc2007_xfer(tsc, READ_Y);
119
120 /* turn y- off, x+ on, then leave in lowpower */
121 tc->x = tsc2007_xfer(tsc, READ_X);
122
123 /* turn y+ off, x- on; we'll use formula #1 */
124 tc->z1 = tsc2007_xfer(tsc, READ_Z1);
125 tc->z2 = tsc2007_xfer(tsc, READ_Z2);
126
127 /* Prepare for next touch reading - power down ADC, enable PENIRQ */
128 tsc2007_xfer(tsc, PWRDOWN);
129}
130
131static u32 tsc2007_calculate_pressure(struct tsc2007 *tsc, struct ts_event *tc)
132{
133 u32 rt = 0;
134
135 /* range filtering */
136 if (tc->x == MAX_12BIT)
137 tc->x = 0;
138
139 if (likely(tc->x && tc->z1)) {
140 /* compute touch pressure resistance using equation #1 */
141 rt = tc->z2 - tc->z1;
142 rt *= tc->x;
143 rt *= tsc->x_plate_ohms;
144 rt /= tc->z1;
145 rt = (rt + 2047) >> 12;
146 }
147
148 return rt;
149}
150
151static bool tsc2007_is_pen_down(struct tsc2007 *ts)
152{
153 /*
154 * NOTE: We can't rely on the pressure to determine the pen down
155 * state, even though this controller has a pressure sensor.
156 * The pressure value can fluctuate for quite a while after
157 * lifting the pen and in some cases may not even settle at the
158 * expected value.
159 *
160 * The only safe way to check for the pen up condition is in the
161 * work function by reading the pen signal state (it's a GPIO
162 * and IRQ). Unfortunately such callback is not always available,
163 * in that case we assume that the pen is down and expect caller
164 * to fall back on the pressure reading.
165 */
166
167 if (!ts->get_pendown_state)
168 return true;
169
170 return ts->get_pendown_state(&ts->client->dev);
171}
172
173static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
174{
175 struct tsc2007 *ts = handle;
176 struct input_dev *input = ts->input;
177 struct ts_event tc;
178 u32 rt;
179
180 while (!ts->stopped && tsc2007_is_pen_down(ts)) {
181
182 /* pen is down, continue with the measurement */
183 tsc2007_read_values(ts, &tc);
184
185 rt = tsc2007_calculate_pressure(ts, &tc);
186
187 if (!rt && !ts->get_pendown_state) {
188 /*
189 * If pressure reported is 0 and we don't have
190 * callback to check pendown state, we have to
191 * assume that pen was lifted up.
192 */
193 break;
194 }
195
196 if (rt <= ts->max_rt) {
197 dev_dbg(&ts->client->dev,
198 "DOWN point(%4d,%4d), pressure (%4u)\n",
199 tc.x, tc.y, rt);
200
201 input_report_key(input, BTN_TOUCH, 1);
202 input_report_abs(input, ABS_X, tc.x);
203 input_report_abs(input, ABS_Y, tc.y);
204 input_report_abs(input, ABS_PRESSURE, rt);
205
206 input_sync(input);
207
208 } else {
209 /*
210 * Sample found inconsistent by debouncing or pressure is
211 * beyond the maximum. Don't report it to user space,
212 * repeat at least once more the measurement.
213 */
214 dev_dbg(&ts->client->dev, "ignored pressure %d\n", rt);
215 }
216
217 wait_event_timeout(ts->wait, ts->stopped, ts->poll_period);
218 }
219
220 dev_dbg(&ts->client->dev, "UP\n");
221
222 input_report_key(input, BTN_TOUCH, 0);
223 input_report_abs(input, ABS_PRESSURE, 0);
224 input_sync(input);
225
226 if (ts->clear_penirq)
227 ts->clear_penirq();
228
229 return IRQ_HANDLED;
230}
231
232static irqreturn_t tsc2007_hard_irq(int irq, void *handle)
233{
234 struct tsc2007 *ts = handle;
235
236 if (tsc2007_is_pen_down(ts))
237 return IRQ_WAKE_THREAD;
238
239 if (ts->clear_penirq)
240 ts->clear_penirq();
241
242 return IRQ_HANDLED;
243}
244
245static void tsc2007_stop(struct tsc2007 *ts)
246{
247 ts->stopped = true;
248 mb();
249 wake_up(&ts->wait);
250
251 disable_irq(ts->irq);
252}
253
254static int tsc2007_open(struct input_dev *input_dev)
255{
256 struct tsc2007 *ts = input_get_drvdata(input_dev);
257 int err;
258
259 ts->stopped = false;
260 mb();
261
262 enable_irq(ts->irq);
263
264 /* Prepare for touch readings - power down ADC and enable PENIRQ */
265 err = tsc2007_xfer(ts, PWRDOWN);
266 if (err < 0) {
267 tsc2007_stop(ts);
268 return err;
269 }
270
271 return 0;
272}
273
274static void tsc2007_close(struct input_dev *input_dev)
275{
276 struct tsc2007 *ts = input_get_drvdata(input_dev);
277
278 tsc2007_stop(ts);
279}
280
281#ifdef CONFIG_OF
282static int tsc2007_get_pendown_state_gpio(struct device *dev)
283{
284 struct i2c_client *client = to_i2c_client(dev);
285 struct tsc2007 *ts = i2c_get_clientdata(client);
286
287 return !gpio_get_value(ts->gpio);
288}
289
290static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts)
291{
292 struct device_node *np = client->dev.of_node;
293 u32 val32;
294 u64 val64;
295
296 if (!np) {
297 dev_err(&client->dev, "missing device tree data\n");
298 return -EINVAL;
299 }
300
301 if (!of_property_read_u32(np, "ti,max-rt", &val32))
302 ts->max_rt = val32;
303 else
304 ts->max_rt = MAX_12BIT;
305
306 if (!of_property_read_u32(np, "ti,fuzzx", &val32))
307 ts->fuzzx = val32;
308
309 if (!of_property_read_u32(np, "ti,fuzzy", &val32))
310 ts->fuzzy = val32;
311
312 if (!of_property_read_u32(np, "ti,fuzzz", &val32))
313 ts->fuzzz = val32;
314
315 if (!of_property_read_u64(np, "ti,poll-period", &val64))
316 ts->poll_period = msecs_to_jiffies(val64);
317 else
318 ts->poll_period = msecs_to_jiffies(1);
319
320 if (!of_property_read_u32(np, "ti,x-plate-ohms", &val32)) {
321 ts->x_plate_ohms = val32;
322 } else {
323 dev_err(&client->dev, "missing ti,x-plate-ohms devicetree property.");
324 return -EINVAL;
325 }
326
327 ts->gpio = of_get_gpio(np, 0);
328 if (gpio_is_valid(ts->gpio))
329 ts->get_pendown_state = tsc2007_get_pendown_state_gpio;
330 else
331 dev_warn(&client->dev,
332 "GPIO not specified in DT (of_get_gpio returned %d)\n",
333 ts->gpio);
334
335 return 0;
336}
337#else
338static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts)
339{
340 dev_err(&client->dev, "platform data is required!\n");
341 return -EINVAL;
342}
343#endif
344
345static int tsc2007_probe_pdev(struct i2c_client *client, struct tsc2007 *ts,
346 const struct tsc2007_platform_data *pdata,
347 const struct i2c_device_id *id)
348{
349 ts->model = pdata->model;
350 ts->x_plate_ohms = pdata->x_plate_ohms;
351 ts->max_rt = pdata->max_rt ? : MAX_12BIT;
352 ts->poll_period = msecs_to_jiffies(pdata->poll_period ? : 1);
353 ts->get_pendown_state = pdata->get_pendown_state;
354 ts->clear_penirq = pdata->clear_penirq;
355 ts->fuzzx = pdata->fuzzx;
356 ts->fuzzy = pdata->fuzzy;
357 ts->fuzzz = pdata->fuzzz;
358
359 if (pdata->x_plate_ohms == 0) {
360 dev_err(&client->dev, "x_plate_ohms is not set up in platform data");
361 return -EINVAL;
362 }
363
364 return 0;
365}
366
367static void tsc2007_call_exit_platform_hw(void *data)
368{
369 struct device *dev = data;
370 const struct tsc2007_platform_data *pdata = dev_get_platdata(dev);
371
372 pdata->exit_platform_hw();
373}
374
375static int tsc2007_probe(struct i2c_client *client,
376 const struct i2c_device_id *id)
377{
378 const struct tsc2007_platform_data *pdata = dev_get_platdata(&client->dev);
379 struct tsc2007 *ts;
380 struct input_dev *input_dev;
381 int err;
382
383 if (!i2c_check_functionality(client->adapter,
384 I2C_FUNC_SMBUS_READ_WORD_DATA))
385 return -EIO;
386
387 ts = devm_kzalloc(&client->dev, sizeof(struct tsc2007), GFP_KERNEL);
388 if (!ts)
389 return -ENOMEM;
390
391 if (pdata)
392 err = tsc2007_probe_pdev(client, ts, pdata, id);
393 else
394 err = tsc2007_probe_dt(client, ts);
395 if (err)
396 return err;
397
398 input_dev = devm_input_allocate_device(&client->dev);
399 if (!input_dev)
400 return -ENOMEM;
401
402 i2c_set_clientdata(client, ts);
403
404 ts->client = client;
405 ts->irq = client->irq;
406 ts->input = input_dev;
407 init_waitqueue_head(&ts->wait);
408
409 snprintf(ts->phys, sizeof(ts->phys),
410 "%s/input0", dev_name(&client->dev));
411
412 input_dev->name = "TSC2007 Touchscreen";
413 input_dev->phys = ts->phys;
414 input_dev->id.bustype = BUS_I2C;
415
416 input_dev->open = tsc2007_open;
417 input_dev->close = tsc2007_close;
418
419 input_set_drvdata(input_dev, ts);
420
421 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
422 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
423
424 input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, ts->fuzzx, 0);
425 input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, ts->fuzzy, 0);
426 input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT,
427 ts->fuzzz, 0);
428
429 if (pdata) {
430 if (pdata->exit_platform_hw) {
431 err = devm_add_action(&client->dev,
432 tsc2007_call_exit_platform_hw,
433 &client->dev);
434 if (err) {
435 dev_err(&client->dev,
436 "Failed to register exit_platform_hw action, %d\n",
437 err);
438 return err;
439 }
440 }
441
442 if (pdata->init_platform_hw)
443 pdata->init_platform_hw();
444 }
445
446 err = devm_request_threaded_irq(&client->dev, ts->irq,
447 tsc2007_hard_irq, tsc2007_soft_irq,
448 IRQF_ONESHOT,
449 client->dev.driver->name, ts);
450 if (err) {
451 dev_err(&client->dev, "Failed to request irq %d: %d\n",
452 ts->irq, err);
453 return err;
454 }
455
456 tsc2007_stop(ts);
457
458 err = input_register_device(input_dev);
459 if (err) {
460 dev_err(&client->dev,
461 "Failed to register input device: %d\n", err);
462 return err;
463 }
464
465 return 0;
466}
467
468static const struct i2c_device_id tsc2007_idtable[] = {
469 { "tsc2007", 0 },
470 { }
471};
472
473MODULE_DEVICE_TABLE(i2c, tsc2007_idtable);
474
475#ifdef CONFIG_OF
476static const struct of_device_id tsc2007_of_match[] = {
477 { .compatible = "ti,tsc2007" },
478 { /* sentinel */ }
479};
480MODULE_DEVICE_TABLE(of, tsc2007_of_match);
481#endif
482
483static struct i2c_driver tsc2007_driver = {
484 .driver = {
485 .name = "tsc2007",
486 .of_match_table = of_match_ptr(tsc2007_of_match),
487 },
488 .id_table = tsc2007_idtable,
489 .probe = tsc2007_probe,
490};
491
492module_i2c_driver(tsc2007_driver);
493
494MODULE_AUTHOR("Kwangwoo Lee <kwlee@mtekvision.com>");
495MODULE_DESCRIPTION("TSC2007 TouchScreen Driver");
496MODULE_LICENSE("GPL");
1/*
2 * drivers/input/touchscreen/tsc2007.c
3 *
4 * Copyright (c) 2008 MtekVision Co., Ltd.
5 * Kwangwoo Lee <kwlee@mtekvision.com>
6 *
7 * Using code from:
8 * - ads7846.c
9 * Copyright (c) 2005 David Brownell
10 * Copyright (c) 2006 Nokia Corporation
11 * - corgi_ts.c
12 * Copyright (C) 2004-2005 Richard Purdie
13 * - omap_ts.[hc], ads7846.h, ts_osk.c
14 * Copyright (C) 2002 MontaVista Software
15 * Copyright (C) 2004 Texas Instruments
16 * Copyright (C) 2005 Dirk Behme
17 *
18 * This program is free software; you can redistribute it and/or modify
19 * it under the terms of the GNU General Public License version 2 as
20 * published by the Free Software Foundation.
21 */
22
23#include <linux/module.h>
24#include <linux/slab.h>
25#include <linux/input.h>
26#include <linux/interrupt.h>
27#include <linux/i2c.h>
28#include <linux/i2c/tsc2007.h>
29
30#define TSC2007_MEASURE_TEMP0 (0x0 << 4)
31#define TSC2007_MEASURE_AUX (0x2 << 4)
32#define TSC2007_MEASURE_TEMP1 (0x4 << 4)
33#define TSC2007_ACTIVATE_XN (0x8 << 4)
34#define TSC2007_ACTIVATE_YN (0x9 << 4)
35#define TSC2007_ACTIVATE_YP_XN (0xa << 4)
36#define TSC2007_SETUP (0xb << 4)
37#define TSC2007_MEASURE_X (0xc << 4)
38#define TSC2007_MEASURE_Y (0xd << 4)
39#define TSC2007_MEASURE_Z1 (0xe << 4)
40#define TSC2007_MEASURE_Z2 (0xf << 4)
41
42#define TSC2007_POWER_OFF_IRQ_EN (0x0 << 2)
43#define TSC2007_ADC_ON_IRQ_DIS0 (0x1 << 2)
44#define TSC2007_ADC_OFF_IRQ_EN (0x2 << 2)
45#define TSC2007_ADC_ON_IRQ_DIS1 (0x3 << 2)
46
47#define TSC2007_12BIT (0x0 << 1)
48#define TSC2007_8BIT (0x1 << 1)
49
50#define MAX_12BIT ((1 << 12) - 1)
51
52#define ADC_ON_12BIT (TSC2007_12BIT | TSC2007_ADC_ON_IRQ_DIS0)
53
54#define READ_Y (ADC_ON_12BIT | TSC2007_MEASURE_Y)
55#define READ_Z1 (ADC_ON_12BIT | TSC2007_MEASURE_Z1)
56#define READ_Z2 (ADC_ON_12BIT | TSC2007_MEASURE_Z2)
57#define READ_X (ADC_ON_12BIT | TSC2007_MEASURE_X)
58#define PWRDOWN (TSC2007_12BIT | TSC2007_POWER_OFF_IRQ_EN)
59
60struct ts_event {
61 u16 x;
62 u16 y;
63 u16 z1, z2;
64};
65
66struct tsc2007 {
67 struct input_dev *input;
68 char phys[32];
69
70 struct i2c_client *client;
71
72 u16 model;
73 u16 x_plate_ohms;
74 u16 max_rt;
75 unsigned long poll_delay;
76 unsigned long poll_period;
77
78 int irq;
79
80 wait_queue_head_t wait;
81 bool stopped;
82
83 int (*get_pendown_state)(void);
84 void (*clear_penirq)(void);
85};
86
87static inline int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd)
88{
89 s32 data;
90 u16 val;
91
92 data = i2c_smbus_read_word_data(tsc->client, cmd);
93 if (data < 0) {
94 dev_err(&tsc->client->dev, "i2c io error: %d\n", data);
95 return data;
96 }
97
98 /* The protocol and raw data format from i2c interface:
99 * S Addr Wr [A] Comm [A] S Addr Rd [A] [DataLow] A [DataHigh] NA P
100 * Where DataLow has [D11-D4], DataHigh has [D3-D0 << 4 | Dummy 4bit].
101 */
102 val = swab16(data) >> 4;
103
104 dev_dbg(&tsc->client->dev, "data: 0x%x, val: 0x%x\n", data, val);
105
106 return val;
107}
108
109static void tsc2007_read_values(struct tsc2007 *tsc, struct ts_event *tc)
110{
111 /* y- still on; turn on only y+ (and ADC) */
112 tc->y = tsc2007_xfer(tsc, READ_Y);
113
114 /* turn y- off, x+ on, then leave in lowpower */
115 tc->x = tsc2007_xfer(tsc, READ_X);
116
117 /* turn y+ off, x- on; we'll use formula #1 */
118 tc->z1 = tsc2007_xfer(tsc, READ_Z1);
119 tc->z2 = tsc2007_xfer(tsc, READ_Z2);
120
121 /* Prepare for next touch reading - power down ADC, enable PENIRQ */
122 tsc2007_xfer(tsc, PWRDOWN);
123}
124
125static u32 tsc2007_calculate_pressure(struct tsc2007 *tsc, struct ts_event *tc)
126{
127 u32 rt = 0;
128
129 /* range filtering */
130 if (tc->x == MAX_12BIT)
131 tc->x = 0;
132
133 if (likely(tc->x && tc->z1)) {
134 /* compute touch pressure resistance using equation #1 */
135 rt = tc->z2 - tc->z1;
136 rt *= tc->x;
137 rt *= tsc->x_plate_ohms;
138 rt /= tc->z1;
139 rt = (rt + 2047) >> 12;
140 }
141
142 return rt;
143}
144
145static bool tsc2007_is_pen_down(struct tsc2007 *ts)
146{
147 /*
148 * NOTE: We can't rely on the pressure to determine the pen down
149 * state, even though this controller has a pressure sensor.
150 * The pressure value can fluctuate for quite a while after
151 * lifting the pen and in some cases may not even settle at the
152 * expected value.
153 *
154 * The only safe way to check for the pen up condition is in the
155 * work function by reading the pen signal state (it's a GPIO
156 * and IRQ). Unfortunately such callback is not always available,
157 * in that case we assume that the pen is down and expect caller
158 * to fall back on the pressure reading.
159 */
160
161 if (!ts->get_pendown_state)
162 return true;
163
164 return ts->get_pendown_state();
165}
166
167static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
168{
169 struct tsc2007 *ts = handle;
170 struct input_dev *input = ts->input;
171 struct ts_event tc;
172 u32 rt;
173
174 while (!ts->stopped && tsc2007_is_pen_down(ts)) {
175
176 /* pen is down, continue with the measurement */
177 tsc2007_read_values(ts, &tc);
178
179 rt = tsc2007_calculate_pressure(ts, &tc);
180
181 if (rt == 0 && !ts->get_pendown_state) {
182 /*
183 * If pressure reported is 0 and we don't have
184 * callback to check pendown state, we have to
185 * assume that pen was lifted up.
186 */
187 break;
188 }
189
190 if (rt <= ts->max_rt) {
191 dev_dbg(&ts->client->dev,
192 "DOWN point(%4d,%4d), pressure (%4u)\n",
193 tc.x, tc.y, rt);
194
195 input_report_key(input, BTN_TOUCH, 1);
196 input_report_abs(input, ABS_X, tc.x);
197 input_report_abs(input, ABS_Y, tc.y);
198 input_report_abs(input, ABS_PRESSURE, rt);
199
200 input_sync(input);
201
202 } else {
203 /*
204 * Sample found inconsistent by debouncing or pressure is
205 * beyond the maximum. Don't report it to user space,
206 * repeat at least once more the measurement.
207 */
208 dev_dbg(&ts->client->dev, "ignored pressure %d\n", rt);
209 }
210
211 wait_event_timeout(ts->wait, ts->stopped,
212 msecs_to_jiffies(ts->poll_period));
213 }
214
215 dev_dbg(&ts->client->dev, "UP\n");
216
217 input_report_key(input, BTN_TOUCH, 0);
218 input_report_abs(input, ABS_PRESSURE, 0);
219 input_sync(input);
220
221 if (ts->clear_penirq)
222 ts->clear_penirq();
223
224 return IRQ_HANDLED;
225}
226
227static irqreturn_t tsc2007_hard_irq(int irq, void *handle)
228{
229 struct tsc2007 *ts = handle;
230
231 if (!ts->get_pendown_state || likely(ts->get_pendown_state()))
232 return IRQ_WAKE_THREAD;
233
234 if (ts->clear_penirq)
235 ts->clear_penirq();
236
237 return IRQ_HANDLED;
238}
239
240static void tsc2007_stop(struct tsc2007 *ts)
241{
242 ts->stopped = true;
243 mb();
244 wake_up(&ts->wait);
245
246 disable_irq(ts->irq);
247}
248
249static int tsc2007_open(struct input_dev *input_dev)
250{
251 struct tsc2007 *ts = input_get_drvdata(input_dev);
252 int err;
253
254 ts->stopped = false;
255 mb();
256
257 enable_irq(ts->irq);
258
259 /* Prepare for touch readings - power down ADC and enable PENIRQ */
260 err = tsc2007_xfer(ts, PWRDOWN);
261 if (err < 0) {
262 tsc2007_stop(ts);
263 return err;
264 }
265
266 return 0;
267}
268
269static void tsc2007_close(struct input_dev *input_dev)
270{
271 struct tsc2007 *ts = input_get_drvdata(input_dev);
272
273 tsc2007_stop(ts);
274}
275
276static int __devinit tsc2007_probe(struct i2c_client *client,
277 const struct i2c_device_id *id)
278{
279 struct tsc2007 *ts;
280 struct tsc2007_platform_data *pdata = client->dev.platform_data;
281 struct input_dev *input_dev;
282 int err;
283
284 if (!pdata) {
285 dev_err(&client->dev, "platform data is required!\n");
286 return -EINVAL;
287 }
288
289 if (!i2c_check_functionality(client->adapter,
290 I2C_FUNC_SMBUS_READ_WORD_DATA))
291 return -EIO;
292
293 ts = kzalloc(sizeof(struct tsc2007), GFP_KERNEL);
294 input_dev = input_allocate_device();
295 if (!ts || !input_dev) {
296 err = -ENOMEM;
297 goto err_free_mem;
298 }
299
300 ts->client = client;
301 ts->irq = client->irq;
302 ts->input = input_dev;
303 init_waitqueue_head(&ts->wait);
304
305 ts->model = pdata->model;
306 ts->x_plate_ohms = pdata->x_plate_ohms;
307 ts->max_rt = pdata->max_rt ? : MAX_12BIT;
308 ts->poll_delay = pdata->poll_delay ? : 1;
309 ts->poll_period = pdata->poll_period ? : 1;
310 ts->get_pendown_state = pdata->get_pendown_state;
311 ts->clear_penirq = pdata->clear_penirq;
312
313 if (pdata->x_plate_ohms == 0) {
314 dev_err(&client->dev, "x_plate_ohms is not set up in platform data");
315 err = -EINVAL;
316 goto err_free_mem;
317 }
318
319 snprintf(ts->phys, sizeof(ts->phys),
320 "%s/input0", dev_name(&client->dev));
321
322 input_dev->name = "TSC2007 Touchscreen";
323 input_dev->phys = ts->phys;
324 input_dev->id.bustype = BUS_I2C;
325
326 input_dev->open = tsc2007_open;
327 input_dev->close = tsc2007_close;
328
329 input_set_drvdata(input_dev, ts);
330
331 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
332 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
333
334 input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, pdata->fuzzx, 0);
335 input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, pdata->fuzzy, 0);
336 input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT,
337 pdata->fuzzz, 0);
338
339 if (pdata->init_platform_hw)
340 pdata->init_platform_hw();
341
342 err = request_threaded_irq(ts->irq, tsc2007_hard_irq, tsc2007_soft_irq,
343 IRQF_ONESHOT, client->dev.driver->name, ts);
344 if (err < 0) {
345 dev_err(&client->dev, "irq %d busy?\n", ts->irq);
346 goto err_free_mem;
347 }
348
349 tsc2007_stop(ts);
350
351 err = input_register_device(input_dev);
352 if (err)
353 goto err_free_irq;
354
355 i2c_set_clientdata(client, ts);
356
357 return 0;
358
359 err_free_irq:
360 free_irq(ts->irq, ts);
361 if (pdata->exit_platform_hw)
362 pdata->exit_platform_hw();
363 err_free_mem:
364 input_free_device(input_dev);
365 kfree(ts);
366 return err;
367}
368
369static int __devexit tsc2007_remove(struct i2c_client *client)
370{
371 struct tsc2007 *ts = i2c_get_clientdata(client);
372 struct tsc2007_platform_data *pdata = client->dev.platform_data;
373
374 free_irq(ts->irq, ts);
375
376 if (pdata->exit_platform_hw)
377 pdata->exit_platform_hw();
378
379 input_unregister_device(ts->input);
380 kfree(ts);
381
382 return 0;
383}
384
385static const struct i2c_device_id tsc2007_idtable[] = {
386 { "tsc2007", 0 },
387 { }
388};
389
390MODULE_DEVICE_TABLE(i2c, tsc2007_idtable);
391
392static struct i2c_driver tsc2007_driver = {
393 .driver = {
394 .owner = THIS_MODULE,
395 .name = "tsc2007"
396 },
397 .id_table = tsc2007_idtable,
398 .probe = tsc2007_probe,
399 .remove = __devexit_p(tsc2007_remove),
400};
401
402module_i2c_driver(tsc2007_driver);
403
404MODULE_AUTHOR("Kwangwoo Lee <kwlee@mtekvision.com>");
405MODULE_DESCRIPTION("TSC2007 TouchScreen Driver");
406MODULE_LICENSE("GPL");