1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16#include <linux/module.h>
17#include <linux/workqueue.h>
18#include <linux/slab.h>
19#include <linux/input.h>
20#include <linux/input-polldev.h>
21#include <linux/platform_device.h>
22#include <linux/mfd/tps6507x.h>
23#include <linux/input/tps6507x-ts.h>
24#include <linux/delay.h>
25
26#define TSC_DEFAULT_POLL_PERIOD 30
27#define TPS_DEFAULT_MIN_PRESSURE 0x30
28#define MAX_10BIT ((1 << 10) - 1)
29
30#define TPS6507X_ADCONFIG_CONVERT_TS (TPS6507X_ADCONFIG_AD_ENABLE | \
31 TPS6507X_ADCONFIG_START_CONVERSION | \
32 TPS6507X_ADCONFIG_INPUT_REAL_TSC)
33#define TPS6507X_ADCONFIG_POWER_DOWN_TS (TPS6507X_ADCONFIG_INPUT_REAL_TSC)
34
35struct ts_event {
36 u16 x;
37 u16 y;
38 u16 pressure;
39};
40
41struct tps6507x_ts {
42 struct device *dev;
43 struct input_polled_dev *poll_dev;
44 struct tps6507x_dev *mfd;
45 char phys[32];
46 struct ts_event tc;
47 u16 min_pressure;
48 bool pendown;
49};
50
51static int tps6507x_read_u8(struct tps6507x_ts *tsc, u8 reg, u8 *data)
52{
53 int err;
54
55 err = tsc->mfd->read_dev(tsc->mfd, reg, 1, data);
56
57 if (err)
58 return err;
59
60 return 0;
61}
62
63static int tps6507x_write_u8(struct tps6507x_ts *tsc, u8 reg, u8 data)
64{
65 return tsc->mfd->write_dev(tsc->mfd, reg, 1, &data);
66}
67
68static s32 tps6507x_adc_conversion(struct tps6507x_ts *tsc,
69 u8 tsc_mode, u16 *value)
70{
71 s32 ret;
72 u8 adc_status;
73 u8 result;
74
75
76
77 ret = tps6507x_write_u8(tsc, TPS6507X_REG_TSCMODE, tsc_mode);
78 if (ret) {
79 dev_err(tsc->dev, "TSC mode read failed\n");
80 goto err;
81 }
82
83
84
85 ret = tps6507x_write_u8(tsc, TPS6507X_REG_ADCONFIG,
86 TPS6507X_ADCONFIG_CONVERT_TS);
87 if (ret) {
88 dev_err(tsc->dev, "ADC config write failed\n");
89 return ret;
90 }
91
92 do {
93 ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADCONFIG,
94 &adc_status);
95 if (ret) {
96 dev_err(tsc->dev, "ADC config read failed\n");
97 goto err;
98 }
99 } while (adc_status & TPS6507X_ADCONFIG_START_CONVERSION);
100
101 ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADRESULT_2, &result);
102 if (ret) {
103 dev_err(tsc->dev, "ADC result 2 read failed\n");
104 goto err;
105 }
106
107 *value = (result & TPS6507X_REG_ADRESULT_2_MASK) << 8;
108
109 ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADRESULT_1, &result);
110 if (ret) {
111 dev_err(tsc->dev, "ADC result 1 read failed\n");
112 goto err;
113 }
114
115 *value |= result;
116
117 dev_dbg(tsc->dev, "TSC channel %d = 0x%X\n", tsc_mode, *value);
118
119err:
120 return ret;
121}
122
123
124
125
126
127static s32 tps6507x_adc_standby(struct tps6507x_ts *tsc)
128{
129 s32 ret;
130 s32 loops = 0;
131 u8 val;
132
133 ret = tps6507x_write_u8(tsc, TPS6507X_REG_ADCONFIG,
134 TPS6507X_ADCONFIG_INPUT_TSC);
135 if (ret)
136 return ret;
137
138 ret = tps6507x_write_u8(tsc, TPS6507X_REG_TSCMODE,
139 TPS6507X_TSCMODE_STANDBY);
140 if (ret)
141 return ret;
142
143 ret = tps6507x_read_u8(tsc, TPS6507X_REG_INT, &val);
144 if (ret)
145 return ret;
146
147 while (val & TPS6507X_REG_TSC_INT) {
148 mdelay(10);
149 ret = tps6507x_read_u8(tsc, TPS6507X_REG_INT, &val);
150 if (ret)
151 return ret;
152 loops++;
153 }
154
155 return ret;
156}
157
158static void tps6507x_ts_poll(struct input_polled_dev *poll_dev)
159{
160 struct tps6507x_ts *tsc = poll_dev->private;
161 struct input_dev *input_dev = poll_dev->input;
162 bool pendown;
163 s32 ret;
164
165 ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_PRESSURE,
166 &tsc->tc.pressure);
167 if (ret)
168 goto done;
169
170 pendown = tsc->tc.pressure > tsc->min_pressure;
171
172 if (unlikely(!pendown && tsc->pendown)) {
173 dev_dbg(tsc->dev, "UP\n");
174 input_report_key(input_dev, BTN_TOUCH, 0);
175 input_report_abs(input_dev, ABS_PRESSURE, 0);
176 input_sync(input_dev);
177 tsc->pendown = false;
178 }
179
180 if (pendown) {
181
182 if (!tsc->pendown) {
183 dev_dbg(tsc->dev, "DOWN\n");
184 input_report_key(input_dev, BTN_TOUCH, 1);
185 } else
186 dev_dbg(tsc->dev, "still down\n");
187
188 ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_X_POSITION,
189 &tsc->tc.x);
190 if (ret)
191 goto done;
192
193 ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_Y_POSITION,
194 &tsc->tc.y);
195 if (ret)
196 goto done;
197
198 input_report_abs(input_dev, ABS_X, tsc->tc.x);
199 input_report_abs(input_dev, ABS_Y, tsc->tc.y);
200 input_report_abs(input_dev, ABS_PRESSURE, tsc->tc.pressure);
201 input_sync(input_dev);
202 tsc->pendown = true;
203 }
204
205done:
206 tps6507x_adc_standby(tsc);
207}
208
209static int tps6507x_ts_probe(struct platform_device *pdev)
210{
211 struct tps6507x_dev *tps6507x_dev = dev_get_drvdata(pdev->dev.parent);
212 const struct tps6507x_board *tps_board;
213 const struct touchscreen_init_data *init_data;
214 struct tps6507x_ts *tsc;
215 struct input_polled_dev *poll_dev;
216 struct input_dev *input_dev;
217 int error;
218
219
220
221
222
223 tps_board = dev_get_platdata(tps6507x_dev->dev);
224 if (!tps_board) {
225 dev_err(tps6507x_dev->dev,
226 "Could not find tps6507x platform data\n");
227 return -ENODEV;
228 }
229
230
231
232
233
234 init_data = tps_board->tps6507x_ts_init_data;
235
236 tsc = kzalloc(sizeof(struct tps6507x_ts), GFP_KERNEL);
237 if (!tsc) {
238 dev_err(tps6507x_dev->dev, "failed to allocate driver data\n");
239 return -ENOMEM;
240 }
241
242 tsc->mfd = tps6507x_dev;
243 tsc->dev = tps6507x_dev->dev;
244 tsc->min_pressure = init_data ?
245 init_data->min_pressure : TPS_DEFAULT_MIN_PRESSURE;
246
247 snprintf(tsc->phys, sizeof(tsc->phys),
248 "%s/input0", dev_name(tsc->dev));
249
250 poll_dev = input_allocate_polled_device();
251 if (!poll_dev) {
252 dev_err(tsc->dev, "Failed to allocate polled input device.\n");
253 error = -ENOMEM;
254 goto err_free_mem;
255 }
256
257 tsc->poll_dev = poll_dev;
258
259 poll_dev->private = tsc;
260 poll_dev->poll = tps6507x_ts_poll;
261 poll_dev->poll_interval = init_data ?
262 init_data->poll_period : TSC_DEFAULT_POLL_PERIOD;
263
264 input_dev = poll_dev->input;
265 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
266 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
267
268 input_set_abs_params(input_dev, ABS_X, 0, MAX_10BIT, 0, 0);
269 input_set_abs_params(input_dev, ABS_Y, 0, MAX_10BIT, 0, 0);
270 input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_10BIT, 0, 0);
271
272 input_dev->name = "TPS6507x Touchscreen";
273 input_dev->phys = tsc->phys;
274 input_dev->dev.parent = tsc->dev;
275 input_dev->id.bustype = BUS_I2C;
276 if (init_data) {
277 input_dev->id.vendor = init_data->vendor;
278 input_dev->id.product = init_data->product;
279 input_dev->id.version = init_data->version;
280 }
281
282 error = tps6507x_adc_standby(tsc);
283 if (error)
284 goto err_free_polled_dev;
285
286 error = input_register_polled_device(poll_dev);
287 if (error)
288 goto err_free_polled_dev;
289
290 platform_set_drvdata(pdev, tsc);
291
292 return 0;
293
294err_free_polled_dev:
295 input_free_polled_device(poll_dev);
296err_free_mem:
297 kfree(tsc);
298 return error;
299}
300
301static int tps6507x_ts_remove(struct platform_device *pdev)
302{
303 struct tps6507x_ts *tsc = platform_get_drvdata(pdev);
304 struct input_polled_dev *poll_dev = tsc->poll_dev;
305
306 input_unregister_polled_device(poll_dev);
307 input_free_polled_device(poll_dev);
308
309 kfree(tsc);
310
311 return 0;
312}
313
314static struct platform_driver tps6507x_ts_driver = {
315 .driver = {
316 .name = "tps6507x-ts",
317 .owner = THIS_MODULE,
318 },
319 .probe = tps6507x_ts_probe,
320 .remove = tps6507x_ts_remove,
321};
322module_platform_driver(tps6507x_ts_driver);
323
324MODULE_AUTHOR("Todd Fischer <todd.fischer@ridgerun.com>");
325MODULE_DESCRIPTION("TPS6507x - TouchScreen driver");
326MODULE_LICENSE("GPL v2");
327MODULE_ALIAS("platform:tps6507x-ts");
328
