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16#include <linux/module.h>
17#include <linux/workqueue.h>
18#include <linux/slab.h>
19#include <linux/input.h>
20#include <linux/platform_device.h>
21#include <linux/mfd/tps6507x.h>
22#include <linux/input/tps6507x-ts.h>
23#include <linux/delay.h>
24
25#define TSC_DEFAULT_POLL_PERIOD 30
26#define TPS_DEFAULT_MIN_PRESSURE 0x30
27#define MAX_10BIT ((1 << 10) - 1)
28
29#define TPS6507X_ADCONFIG_CONVERT_TS (TPS6507X_ADCONFIG_AD_ENABLE | \
30 TPS6507X_ADCONFIG_START_CONVERSION | \
31 TPS6507X_ADCONFIG_INPUT_REAL_TSC)
32#define TPS6507X_ADCONFIG_POWER_DOWN_TS (TPS6507X_ADCONFIG_INPUT_REAL_TSC)
33
34struct ts_event {
35 u16 x;
36 u16 y;
37 u16 pressure;
38};
39
40struct tps6507x_ts {
41 struct input_dev *input_dev;
42 struct device *dev;
43 char phys[32];
44 struct delayed_work work;
45 unsigned polling;
46 struct ts_event tc;
47 struct tps6507x_dev *mfd;
48 u16 model;
49 unsigned pendown;
50 int irq;
51 void (*clear_penirq)(void);
52 unsigned long poll_period;
53 u16 min_pressure;
54 int vref;
55};
56
57static int tps6507x_read_u8(struct tps6507x_ts *tsc, u8 reg, u8 *data)
58{
59 int err;
60
61 err = tsc->mfd->read_dev(tsc->mfd, reg, 1, data);
62
63 if (err)
64 return err;
65
66 return 0;
67}
68
69static int tps6507x_write_u8(struct tps6507x_ts *tsc, u8 reg, u8 data)
70{
71 return tsc->mfd->write_dev(tsc->mfd, reg, 1, &data);
72}
73
74static s32 tps6507x_adc_conversion(struct tps6507x_ts *tsc,
75 u8 tsc_mode, u16 *value)
76{
77 s32 ret;
78 u8 adc_status;
79 u8 result;
80
81
82
83 ret = tps6507x_write_u8(tsc, TPS6507X_REG_TSCMODE, tsc_mode);
84 if (ret) {
85 dev_err(tsc->dev, "TSC mode read failed\n");
86 goto err;
87 }
88
89
90
91 ret = tps6507x_write_u8(tsc, TPS6507X_REG_ADCONFIG,
92 TPS6507X_ADCONFIG_CONVERT_TS);
93 if (ret) {
94 dev_err(tsc->dev, "ADC config write failed\n");
95 return ret;
96 }
97
98 do {
99 ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADCONFIG,
100 &adc_status);
101 if (ret) {
102 dev_err(tsc->dev, "ADC config read failed\n");
103 goto err;
104 }
105 } while (adc_status & TPS6507X_ADCONFIG_START_CONVERSION);
106
107 ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADRESULT_2, &result);
108 if (ret) {
109 dev_err(tsc->dev, "ADC result 2 read failed\n");
110 goto err;
111 }
112
113 *value = (result & TPS6507X_REG_ADRESULT_2_MASK) << 8;
114
115 ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADRESULT_1, &result);
116 if (ret) {
117 dev_err(tsc->dev, "ADC result 1 read failed\n");
118 goto err;
119 }
120
121 *value |= result;
122
123 dev_dbg(tsc->dev, "TSC channel %d = 0x%X\n", tsc_mode, *value);
124
125err:
126 return ret;
127}
128
129
130
131
132
133static s32 tps6507x_adc_standby(struct tps6507x_ts *tsc)
134{
135 s32 ret;
136 s32 loops = 0;
137 u8 val;
138
139 ret = tps6507x_write_u8(tsc, TPS6507X_REG_ADCONFIG,
140 TPS6507X_ADCONFIG_INPUT_TSC);
141 if (ret)
142 return ret;
143
144 ret = tps6507x_write_u8(tsc, TPS6507X_REG_TSCMODE,
145 TPS6507X_TSCMODE_STANDBY);
146 if (ret)
147 return ret;
148
149 ret = tps6507x_read_u8(tsc, TPS6507X_REG_INT, &val);
150 if (ret)
151 return ret;
152
153 while (val & TPS6507X_REG_TSC_INT) {
154 mdelay(10);
155 ret = tps6507x_read_u8(tsc, TPS6507X_REG_INT, &val);
156 if (ret)
157 return ret;
158 loops++;
159 }
160
161 return ret;
162}
163
164static void tps6507x_ts_handler(struct work_struct *work)
165{
166 struct tps6507x_ts *tsc = container_of(work,
167 struct tps6507x_ts, work.work);
168 struct input_dev *input_dev = tsc->input_dev;
169 int pendown;
170 int schd;
171 int poll = 0;
172 s32 ret;
173
174 ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_PRESSURE,
175 &tsc->tc.pressure);
176 if (ret)
177 goto done;
178
179 pendown = tsc->tc.pressure > tsc->min_pressure;
180
181 if (unlikely(!pendown && tsc->pendown)) {
182 dev_dbg(tsc->dev, "UP\n");
183 input_report_key(input_dev, BTN_TOUCH, 0);
184 input_report_abs(input_dev, ABS_PRESSURE, 0);
185 input_sync(input_dev);
186 tsc->pendown = 0;
187 }
188
189 if (pendown) {
190
191 if (!tsc->pendown) {
192 dev_dbg(tsc->dev, "DOWN\n");
193 input_report_key(input_dev, BTN_TOUCH, 1);
194 } else
195 dev_dbg(tsc->dev, "still down\n");
196
197 ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_X_POSITION,
198 &tsc->tc.x);
199 if (ret)
200 goto done;
201
202 ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_Y_POSITION,
203 &tsc->tc.y);
204 if (ret)
205 goto done;
206
207 input_report_abs(input_dev, ABS_X, tsc->tc.x);
208 input_report_abs(input_dev, ABS_Y, tsc->tc.y);
209 input_report_abs(input_dev, ABS_PRESSURE, tsc->tc.pressure);
210 input_sync(input_dev);
211 tsc->pendown = 1;
212 poll = 1;
213 }
214
215done:
216
217 poll = 1;
218
219 if (poll) {
220 schd = schedule_delayed_work(&tsc->work,
221 msecs_to_jiffies(tsc->poll_period));
222 if (schd)
223 tsc->polling = 1;
224 else {
225 tsc->polling = 0;
226 dev_err(tsc->dev, "re-schedule failed");
227 }
228 } else
229 tsc->polling = 0;
230
231 ret = tps6507x_adc_standby(tsc);
232}
233
234static int tps6507x_ts_probe(struct platform_device *pdev)
235{
236 int error;
237 struct tps6507x_ts *tsc;
238 struct tps6507x_dev *tps6507x_dev = dev_get_drvdata(pdev->dev.parent);
239 struct touchscreen_init_data *init_data;
240 struct input_dev *input_dev;
241 struct tps6507x_board *tps_board;
242 int schd;
243
244
245
246
247
248
249 tps_board = (struct tps6507x_board *)tps6507x_dev->dev->platform_data;
250
251 if (!tps_board) {
252 dev_err(tps6507x_dev->dev,
253 "Could not find tps6507x platform data\n");
254 return -EIO;
255 }
256
257
258
259
260
261
262 init_data = tps_board->tps6507x_ts_init_data;
263
264 tsc = kzalloc(sizeof(struct tps6507x_ts), GFP_KERNEL);
265 if (!tsc) {
266 dev_err(tps6507x_dev->dev, "failed to allocate driver data\n");
267 error = -ENOMEM;
268 goto err0;
269 }
270
271 tps6507x_dev->ts = tsc;
272 tsc->mfd = tps6507x_dev;
273 tsc->dev = tps6507x_dev->dev;
274 input_dev = input_allocate_device();
275 if (!input_dev) {
276 dev_err(tsc->dev, "Failed to allocate input device.\n");
277 error = -ENOMEM;
278 goto err1;
279 }
280
281 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
282 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
283
284 input_set_abs_params(input_dev, ABS_X, 0, MAX_10BIT, 0, 0);
285 input_set_abs_params(input_dev, ABS_Y, 0, MAX_10BIT, 0, 0);
286 input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_10BIT, 0, 0);
287
288 input_dev->name = "TPS6507x Touchscreen";
289 input_dev->id.bustype = BUS_I2C;
290 input_dev->dev.parent = tsc->dev;
291
292 snprintf(tsc->phys, sizeof(tsc->phys),
293 "%s/input0", dev_name(tsc->dev));
294 input_dev->phys = tsc->phys;
295
296 dev_dbg(tsc->dev, "device: %s\n", input_dev->phys);
297
298 input_set_drvdata(input_dev, tsc);
299
300 tsc->input_dev = input_dev;
301
302 INIT_DELAYED_WORK(&tsc->work, tps6507x_ts_handler);
303
304 if (init_data) {
305 tsc->poll_period = init_data->poll_period;
306 tsc->vref = init_data->vref;
307 tsc->min_pressure = init_data->min_pressure;
308 input_dev->id.vendor = init_data->vendor;
309 input_dev->id.product = init_data->product;
310 input_dev->id.version = init_data->version;
311 } else {
312 tsc->poll_period = TSC_DEFAULT_POLL_PERIOD;
313 tsc->min_pressure = TPS_DEFAULT_MIN_PRESSURE;
314 }
315
316 error = tps6507x_adc_standby(tsc);
317 if (error)
318 goto err2;
319
320 error = input_register_device(input_dev);
321 if (error)
322 goto err2;
323
324 schd = schedule_delayed_work(&tsc->work,
325 msecs_to_jiffies(tsc->poll_period));
326
327 if (schd)
328 tsc->polling = 1;
329 else {
330 tsc->polling = 0;
331 dev_err(tsc->dev, "schedule failed");
332 goto err2;
333 }
334 platform_set_drvdata(pdev, tps6507x_dev);
335
336 return 0;
337
338err2:
339 cancel_delayed_work_sync(&tsc->work);
340 input_free_device(input_dev);
341err1:
342 kfree(tsc);
343 tps6507x_dev->ts = NULL;
344err0:
345 return error;
346}
347
348static int tps6507x_ts_remove(struct platform_device *pdev)
349{
350 struct tps6507x_dev *tps6507x_dev = platform_get_drvdata(pdev);
351 struct tps6507x_ts *tsc = tps6507x_dev->ts;
352 struct input_dev *input_dev = tsc->input_dev;
353
354 cancel_delayed_work_sync(&tsc->work);
355
356 input_unregister_device(input_dev);
357
358 tps6507x_dev->ts = NULL;
359 kfree(tsc);
360
361 return 0;
362}
363
364static struct platform_driver tps6507x_ts_driver = {
365 .driver = {
366 .name = "tps6507x-ts",
367 .owner = THIS_MODULE,
368 },
369 .probe = tps6507x_ts_probe,
370 .remove = tps6507x_ts_remove,
371};
372module_platform_driver(tps6507x_ts_driver);
373
374MODULE_AUTHOR("Todd Fischer <todd.fischer@ridgerun.com>");
375MODULE_DESCRIPTION("TPS6507x - TouchScreen driver");
376MODULE_LICENSE("GPL v2");
377MODULE_ALIAS("platform:tps6507x-ts");
378
