2 * drivers/input/touchscreen/tps6507x_ts.c
4 * Touchscreen driver for the tps6507x chip.
6 * Copyright (c) 2009 RidgeRun (todd.fischer@ridgerun.com)
10 * Using code from tsc2007, MtekVision Co., Ltd.
12 * For licencing details see kernel-base/COPYING
14 * TPS65070, TPS65073, TPS650731, and TPS650732 support
15 * 10 bit touch screen interface.
18 #include <linux/module.h>
19 #include <linux/workqueue.h>
20 #include <linux/slab.h>
21 #include <linux/input.h>
22 #include <linux/platform_device.h>
23 #include <linux/mfd/tps6507x.h>
24 #include <linux/input/tps6507x-ts.h>
25 #include <linux/delay.h>
27 #define TSC_DEFAULT_POLL_PERIOD 30 /* ms */
28 #define TPS_DEFAULT_MIN_PRESSURE 0x30
29 #define MAX_10BIT ((1 << 10) - 1)
31 #define TPS6507X_ADCONFIG_CONVERT_TS (TPS6507X_ADCONFIG_AD_ENABLE | \
32 TPS6507X_ADCONFIG_START_CONVERSION | \
33 TPS6507X_ADCONFIG_INPUT_REAL_TSC)
34 #define TPS6507X_ADCONFIG_POWER_DOWN_TS (TPS6507X_ADCONFIG_INPUT_REAL_TSC)
43 struct input_dev *input_dev;
46 struct workqueue_struct *wq;
47 struct delayed_work work;
48 unsigned polling; /* polling is active */
50 struct tps6507x_dev *mfd;
54 void (*clear_penirq)(void);
55 unsigned long poll_period; /* ms */
57 int vref; /* non-zero to leave vref on */
60 static int tps6507x_read_u8(struct tps6507x_ts *tsc, u8 reg, u8 *data)
64 err = tsc->mfd->read_dev(tsc->mfd, reg, 1, data);
72 static int tps6507x_write_u8(struct tps6507x_ts *tsc, u8 reg, u8 data)
74 return tsc->mfd->write_dev(tsc->mfd, reg, 1, &data);
77 static s32 tps6507x_adc_conversion(struct tps6507x_ts *tsc,
78 u8 tsc_mode, u16 *value)
84 /* Route input signal to A/D converter */
86 ret = tps6507x_write_u8(tsc, TPS6507X_REG_TSCMODE, tsc_mode);
88 dev_err(tsc->dev, "TSC mode read failed\n");
92 /* Start A/D conversion */
94 ret = tps6507x_write_u8(tsc, TPS6507X_REG_ADCONFIG,
95 TPS6507X_ADCONFIG_CONVERT_TS);
97 dev_err(tsc->dev, "ADC config write failed\n");
102 ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADCONFIG,
105 dev_err(tsc->dev, "ADC config read failed\n");
108 } while (adc_status & TPS6507X_ADCONFIG_START_CONVERSION);
110 ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADRESULT_2, &result);
112 dev_err(tsc->dev, "ADC result 2 read failed\n");
116 *value = (result & TPS6507X_REG_ADRESULT_2_MASK) << 8;
118 ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADRESULT_1, &result);
120 dev_err(tsc->dev, "ADC result 1 read failed\n");
126 dev_dbg(tsc->dev, "TSC channel %d = 0x%X\n", tsc_mode, *value);
132 /* Need to call tps6507x_adc_standby() after using A/D converter for the
133 * touch screen interrupt to work properly.
136 static s32 tps6507x_adc_standby(struct tps6507x_ts *tsc)
142 ret = tps6507x_write_u8(tsc, TPS6507X_REG_ADCONFIG,
143 TPS6507X_ADCONFIG_INPUT_TSC);
147 ret = tps6507x_write_u8(tsc, TPS6507X_REG_TSCMODE,
148 TPS6507X_TSCMODE_STANDBY);
152 ret = tps6507x_read_u8(tsc, TPS6507X_REG_INT, &val);
156 while (val & TPS6507X_REG_TSC_INT) {
158 ret = tps6507x_read_u8(tsc, TPS6507X_REG_INT, &val);
167 static void tps6507x_ts_handler(struct work_struct *work)
169 struct tps6507x_ts *tsc = container_of(work,
170 struct tps6507x_ts, work.work);
171 struct input_dev *input_dev = tsc->input_dev;
177 ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_PRESSURE,
182 pendown = tsc->tc.pressure > tsc->min_pressure;
184 if (unlikely(!pendown && tsc->pendown)) {
185 dev_dbg(tsc->dev, "UP\n");
186 input_report_key(input_dev, BTN_TOUCH, 0);
187 input_report_abs(input_dev, ABS_PRESSURE, 0);
188 input_sync(input_dev);
195 dev_dbg(tsc->dev, "DOWN\n");
196 input_report_key(input_dev, BTN_TOUCH, 1);
198 dev_dbg(tsc->dev, "still down\n");
200 ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_X_POSITION,
205 ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_Y_POSITION,
210 input_report_abs(input_dev, ABS_X, tsc->tc.x);
211 input_report_abs(input_dev, ABS_Y, tsc->tc.y);
212 input_report_abs(input_dev, ABS_PRESSURE, tsc->tc.pressure);
213 input_sync(input_dev);
219 /* always poll if not using interrupts */
223 schd = queue_delayed_work(tsc->wq, &tsc->work,
224 msecs_to_jiffies(tsc->poll_period));
229 dev_err(tsc->dev, "re-schedule failed");
234 ret = tps6507x_adc_standby(tsc);
237 static int tps6507x_ts_probe(struct platform_device *pdev)
240 struct tps6507x_ts *tsc;
241 struct tps6507x_dev *tps6507x_dev = dev_get_drvdata(pdev->dev.parent);
242 struct touchscreen_init_data *init_data;
243 struct input_dev *input_dev;
244 struct tps6507x_board *tps_board;
248 * tps_board points to pmic related constants
249 * coming from the board-evm file.
252 tps_board = (struct tps6507x_board *)tps6507x_dev->dev->platform_data;
255 dev_err(tps6507x_dev->dev,
256 "Could not find tps6507x platform data\n");
261 * init_data points to array of regulator_init structures
262 * coming from the board-evm file.
265 init_data = tps_board->tps6507x_ts_init_data;
267 tsc = kzalloc(sizeof(struct tps6507x_ts), GFP_KERNEL);
269 dev_err(tps6507x_dev->dev, "failed to allocate driver data\n");
274 tps6507x_dev->ts = tsc;
275 tsc->mfd = tps6507x_dev;
276 tsc->dev = tps6507x_dev->dev;
277 input_dev = input_allocate_device();
279 dev_err(tsc->dev, "Failed to allocate input device.\n");
284 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
285 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
287 input_set_abs_params(input_dev, ABS_X, 0, MAX_10BIT, 0, 0);
288 input_set_abs_params(input_dev, ABS_Y, 0, MAX_10BIT, 0, 0);
289 input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_10BIT, 0, 0);
291 input_dev->name = "TPS6507x Touchscreen";
292 input_dev->id.bustype = BUS_I2C;
293 input_dev->dev.parent = tsc->dev;
295 snprintf(tsc->phys, sizeof(tsc->phys),
296 "%s/input0", dev_name(tsc->dev));
297 input_dev->phys = tsc->phys;
299 dev_dbg(tsc->dev, "device: %s\n", input_dev->phys);
301 input_set_drvdata(input_dev, tsc);
303 tsc->input_dev = input_dev;
305 INIT_DELAYED_WORK(&tsc->work, tps6507x_ts_handler);
306 tsc->wq = create_workqueue("TPS6507x Touchscreen");
309 tsc->poll_period = init_data->poll_period;
310 tsc->vref = init_data->vref;
311 tsc->min_pressure = init_data->min_pressure;
312 input_dev->id.vendor = init_data->vendor;
313 input_dev->id.product = init_data->product;
314 input_dev->id.version = init_data->version;
316 tsc->poll_period = TSC_DEFAULT_POLL_PERIOD;
317 tsc->min_pressure = TPS_DEFAULT_MIN_PRESSURE;
320 error = tps6507x_adc_standby(tsc);
324 error = input_register_device(input_dev);
328 schd = queue_delayed_work(tsc->wq, &tsc->work,
329 msecs_to_jiffies(tsc->poll_period));
335 dev_err(tsc->dev, "schedule failed");
338 platform_set_drvdata(pdev, tps6507x_dev);
343 cancel_delayed_work_sync(&tsc->work);
344 destroy_workqueue(tsc->wq);
345 input_free_device(input_dev);
348 tps6507x_dev->ts = NULL;
353 static int __devexit tps6507x_ts_remove(struct platform_device *pdev)
355 struct tps6507x_dev *tps6507x_dev = platform_get_drvdata(pdev);
356 struct tps6507x_ts *tsc = tps6507x_dev->ts;
357 struct input_dev *input_dev = tsc->input_dev;
359 cancel_delayed_work_sync(&tsc->work);
360 destroy_workqueue(tsc->wq);
362 input_unregister_device(input_dev);
364 tps6507x_dev->ts = NULL;
370 static struct platform_driver tps6507x_ts_driver = {
372 .name = "tps6507x-ts",
373 .owner = THIS_MODULE,
375 .probe = tps6507x_ts_probe,
376 .remove = __devexit_p(tps6507x_ts_remove),
379 static int __init tps6507x_ts_init(void)
381 return platform_driver_register(&tps6507x_ts_driver);
383 module_init(tps6507x_ts_init);
385 static void __exit tps6507x_ts_exit(void)
387 platform_driver_unregister(&tps6507x_ts_driver);
389 module_exit(tps6507x_ts_exit);
391 MODULE_AUTHOR("Todd Fischer <todd.fischer@ridgerun.com>");
392 MODULE_DESCRIPTION("TPS6507x - TouchScreen driver");
393 MODULE_LICENSE("GPL v2");
394 MODULE_ALIAS("platform:tps6507x-tsc");