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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 device *dev;
42 struct input_dev *input;
43 struct tps6507x_dev *mfd;
44 char phys[32];
45 struct ts_event tc;
46 u16 min_pressure;
47 bool pendown;
48};
49
50static int tps6507x_read_u8(struct tps6507x_ts *tsc, u8 reg, u8 *data)
51{
52 return tsc->mfd->read_dev(tsc->mfd, reg, 1, data);
53}
54
55static int tps6507x_write_u8(struct tps6507x_ts *tsc, u8 reg, u8 data)
56{
57 return tsc->mfd->write_dev(tsc->mfd, reg, 1, &data);
58}
59
60static s32 tps6507x_adc_conversion(struct tps6507x_ts *tsc,
61 u8 tsc_mode, u16 *value)
62{
63 s32 ret;
64 u8 adc_status;
65 u8 result;
66
67
68
69 ret = tps6507x_write_u8(tsc, TPS6507X_REG_TSCMODE, tsc_mode);
70 if (ret) {
71 dev_err(tsc->dev, "TSC mode read failed\n");
72 goto err;
73 }
74
75
76
77 ret = tps6507x_write_u8(tsc, TPS6507X_REG_ADCONFIG,
78 TPS6507X_ADCONFIG_CONVERT_TS);
79 if (ret) {
80 dev_err(tsc->dev, "ADC config write failed\n");
81 return ret;
82 }
83
84 do {
85 ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADCONFIG,
86 &adc_status);
87 if (ret) {
88 dev_err(tsc->dev, "ADC config read failed\n");
89 goto err;
90 }
91 } while (adc_status & TPS6507X_ADCONFIG_START_CONVERSION);
92
93 ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADRESULT_2, &result);
94 if (ret) {
95 dev_err(tsc->dev, "ADC result 2 read failed\n");
96 goto err;
97 }
98
99 *value = (result & TPS6507X_REG_ADRESULT_2_MASK) << 8;
100
101 ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADRESULT_1, &result);
102 if (ret) {
103 dev_err(tsc->dev, "ADC result 1 read failed\n");
104 goto err;
105 }
106
107 *value |= result;
108
109 dev_dbg(tsc->dev, "TSC channel %d = 0x%X\n", tsc_mode, *value);
110
111err:
112 return ret;
113}
114
115
116
117
118
119static s32 tps6507x_adc_standby(struct tps6507x_ts *tsc)
120{
121 s32 ret;
122 s32 loops = 0;
123 u8 val;
124
125 ret = tps6507x_write_u8(tsc, TPS6507X_REG_ADCONFIG,
126 TPS6507X_ADCONFIG_INPUT_TSC);
127 if (ret)
128 return ret;
129
130 ret = tps6507x_write_u8(tsc, TPS6507X_REG_TSCMODE,
131 TPS6507X_TSCMODE_STANDBY);
132 if (ret)
133 return ret;
134
135 ret = tps6507x_read_u8(tsc, TPS6507X_REG_INT, &val);
136 if (ret)
137 return ret;
138
139 while (val & TPS6507X_REG_TSC_INT) {
140 mdelay(10);
141 ret = tps6507x_read_u8(tsc, TPS6507X_REG_INT, &val);
142 if (ret)
143 return ret;
144 loops++;
145 }
146
147 return ret;
148}
149
150static void tps6507x_ts_poll(struct input_dev *input_dev)
151{
152 struct tps6507x_ts *tsc = input_get_drvdata(input_dev);
153 bool pendown;
154 s32 ret;
155
156 ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_PRESSURE,
157 &tsc->tc.pressure);
158 if (ret)
159 goto done;
160
161 pendown = tsc->tc.pressure > tsc->min_pressure;
162
163 if (unlikely(!pendown && tsc->pendown)) {
164 dev_dbg(tsc->dev, "UP\n");
165 input_report_key(input_dev, BTN_TOUCH, 0);
166 input_report_abs(input_dev, ABS_PRESSURE, 0);
167 input_sync(input_dev);
168 tsc->pendown = false;
169 }
170
171 if (pendown) {
172
173 if (!tsc->pendown) {
174 dev_dbg(tsc->dev, "DOWN\n");
175 input_report_key(input_dev, BTN_TOUCH, 1);
176 } else
177 dev_dbg(tsc->dev, "still down\n");
178
179 ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_X_POSITION,
180 &tsc->tc.x);
181 if (ret)
182 goto done;
183
184 ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_Y_POSITION,
185 &tsc->tc.y);
186 if (ret)
187 goto done;
188
189 input_report_abs(input_dev, ABS_X, tsc->tc.x);
190 input_report_abs(input_dev, ABS_Y, tsc->tc.y);
191 input_report_abs(input_dev, ABS_PRESSURE, tsc->tc.pressure);
192 input_sync(input_dev);
193 tsc->pendown = true;
194 }
195
196done:
197 tps6507x_adc_standby(tsc);
198}
199
200static int tps6507x_ts_probe(struct platform_device *pdev)
201{
202 struct tps6507x_dev *tps6507x_dev = dev_get_drvdata(pdev->dev.parent);
203 const struct tps6507x_board *tps_board;
204 const struct touchscreen_init_data *init_data;
205 struct tps6507x_ts *tsc;
206 struct input_dev *input_dev;
207 int error;
208
209
210
211
212
213 tps_board = dev_get_platdata(tps6507x_dev->dev);
214 if (!tps_board) {
215 dev_err(tps6507x_dev->dev,
216 "Could not find tps6507x platform data\n");
217 return -ENODEV;
218 }
219
220
221
222
223
224 init_data = tps_board->tps6507x_ts_init_data;
225
226 tsc = devm_kzalloc(&pdev->dev, sizeof(struct tps6507x_ts), GFP_KERNEL);
227 if (!tsc) {
228 dev_err(tps6507x_dev->dev, "failed to allocate driver data\n");
229 return -ENOMEM;
230 }
231
232 tsc->mfd = tps6507x_dev;
233 tsc->dev = tps6507x_dev->dev;
234 tsc->min_pressure = init_data ?
235 init_data->min_pressure : TPS_DEFAULT_MIN_PRESSURE;
236
237 snprintf(tsc->phys, sizeof(tsc->phys),
238 "%s/input0", dev_name(tsc->dev));
239
240 input_dev = devm_input_allocate_device(&pdev->dev);
241 if (!input_dev) {
242 dev_err(tsc->dev, "Failed to allocate polled input device.\n");
243 return -ENOMEM;
244 }
245
246 tsc->input = input_dev;
247 input_set_drvdata(input_dev, tsc);
248
249 input_set_capability(input_dev, EV_KEY, BTN_TOUCH);
250 input_set_abs_params(input_dev, ABS_X, 0, MAX_10BIT, 0, 0);
251 input_set_abs_params(input_dev, ABS_Y, 0, MAX_10BIT, 0, 0);
252 input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_10BIT, 0, 0);
253
254 input_dev->name = "TPS6507x Touchscreen";
255 input_dev->phys = tsc->phys;
256 input_dev->dev.parent = tsc->dev;
257 input_dev->id.bustype = BUS_I2C;
258 if (init_data) {
259 input_dev->id.vendor = init_data->vendor;
260 input_dev->id.product = init_data->product;
261 input_dev->id.version = init_data->version;
262 }
263
264 error = tps6507x_adc_standby(tsc);
265 if (error)
266 return error;
267
268 error = input_setup_polling(input_dev, tps6507x_ts_poll);
269 if (error)
270 return error;
271
272 input_set_poll_interval(input_dev,
273 init_data ? init_data->poll_period :
274 TSC_DEFAULT_POLL_PERIOD);
275
276 error = input_register_device(input_dev);
277 if (error)
278 return error;
279
280 return 0;
281}
282
283static struct platform_driver tps6507x_ts_driver = {
284 .driver = {
285 .name = "tps6507x-ts",
286 },
287 .probe = tps6507x_ts_probe,
288};
289module_platform_driver(tps6507x_ts_driver);
290
291MODULE_AUTHOR("Todd Fischer <todd.fischer@ridgerun.com>");
292MODULE_DESCRIPTION("TPS6507x - TouchScreen driver");
293MODULE_LICENSE("GPL v2");
294MODULE_ALIAS("platform:tps6507x-ts");
295
