2 * Touchscreen driver for the tps6507x chip.
4 * Copyright (c) 2009 RidgeRun (todd.fischer@ridgerun.com)
8 * Using code from tsc2007, MtekVision Co., Ltd.
10 * For licencing details see kernel-base/COPYING
12 * TPS65070, TPS65073, TPS650731, and TPS650732 support
13 * 10 bit touch screen interface.
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>
25 #define TSC_DEFAULT_POLL_PERIOD 30 /* ms */
26 #define TPS_DEFAULT_MIN_PRESSURE 0x30
27 #define MAX_10BIT ((1 << 10) - 1)
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)
41 struct input_dev
*input_dev
;
44 struct delayed_work work
;
45 unsigned polling
; /* polling is active */
47 struct tps6507x_dev
*mfd
;
51 void (*clear_penirq
)(void);
52 unsigned long poll_period
; /* ms */
54 int vref
; /* non-zero to leave vref on */
57 static int tps6507x_read_u8(struct tps6507x_ts
*tsc
, u8 reg
, u8
*data
)
61 err
= tsc
->mfd
->read_dev(tsc
->mfd
, reg
, 1, data
);
69 static int tps6507x_write_u8(struct tps6507x_ts
*tsc
, u8 reg
, u8 data
)
71 return tsc
->mfd
->write_dev(tsc
->mfd
, reg
, 1, &data
);
74 static s32
tps6507x_adc_conversion(struct tps6507x_ts
*tsc
,
75 u8 tsc_mode
, u16
*value
)
81 /* Route input signal to A/D converter */
83 ret
= tps6507x_write_u8(tsc
, TPS6507X_REG_TSCMODE
, tsc_mode
);
85 dev_err(tsc
->dev
, "TSC mode read failed\n");
89 /* Start A/D conversion */
91 ret
= tps6507x_write_u8(tsc
, TPS6507X_REG_ADCONFIG
,
92 TPS6507X_ADCONFIG_CONVERT_TS
);
94 dev_err(tsc
->dev
, "ADC config write failed\n");
99 ret
= tps6507x_read_u8(tsc
, TPS6507X_REG_ADCONFIG
,
102 dev_err(tsc
->dev
, "ADC config read failed\n");
105 } while (adc_status
& TPS6507X_ADCONFIG_START_CONVERSION
);
107 ret
= tps6507x_read_u8(tsc
, TPS6507X_REG_ADRESULT_2
, &result
);
109 dev_err(tsc
->dev
, "ADC result 2 read failed\n");
113 *value
= (result
& TPS6507X_REG_ADRESULT_2_MASK
) << 8;
115 ret
= tps6507x_read_u8(tsc
, TPS6507X_REG_ADRESULT_1
, &result
);
117 dev_err(tsc
->dev
, "ADC result 1 read failed\n");
123 dev_dbg(tsc
->dev
, "TSC channel %d = 0x%X\n", tsc_mode
, *value
);
129 /* Need to call tps6507x_adc_standby() after using A/D converter for the
130 * touch screen interrupt to work properly.
133 static s32
tps6507x_adc_standby(struct tps6507x_ts
*tsc
)
139 ret
= tps6507x_write_u8(tsc
, TPS6507X_REG_ADCONFIG
,
140 TPS6507X_ADCONFIG_INPUT_TSC
);
144 ret
= tps6507x_write_u8(tsc
, TPS6507X_REG_TSCMODE
,
145 TPS6507X_TSCMODE_STANDBY
);
149 ret
= tps6507x_read_u8(tsc
, TPS6507X_REG_INT
, &val
);
153 while (val
& TPS6507X_REG_TSC_INT
) {
155 ret
= tps6507x_read_u8(tsc
, TPS6507X_REG_INT
, &val
);
164 static void tps6507x_ts_handler(struct work_struct
*work
)
166 struct tps6507x_ts
*tsc
= container_of(work
,
167 struct tps6507x_ts
, work
.work
);
168 struct input_dev
*input_dev
= tsc
->input_dev
;
174 ret
= tps6507x_adc_conversion(tsc
, TPS6507X_TSCMODE_PRESSURE
,
179 pendown
= tsc
->tc
.pressure
> tsc
->min_pressure
;
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
);
192 dev_dbg(tsc
->dev
, "DOWN\n");
193 input_report_key(input_dev
, BTN_TOUCH
, 1);
195 dev_dbg(tsc
->dev
, "still down\n");
197 ret
= tps6507x_adc_conversion(tsc
, TPS6507X_TSCMODE_X_POSITION
,
202 ret
= tps6507x_adc_conversion(tsc
, TPS6507X_TSCMODE_Y_POSITION
,
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
);
216 /* always poll if not using interrupts */
220 schd
= schedule_delayed_work(&tsc
->work
,
221 msecs_to_jiffies(tsc
->poll_period
));
226 dev_err(tsc
->dev
, "re-schedule failed");
231 ret
= tps6507x_adc_standby(tsc
);
234 static int tps6507x_ts_probe(struct platform_device
*pdev
)
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
;
245 * tps_board points to pmic related constants
246 * coming from the board-evm file.
249 tps_board
= (struct tps6507x_board
*)tps6507x_dev
->dev
->platform_data
;
252 dev_err(tps6507x_dev
->dev
,
253 "Could not find tps6507x platform data\n");
258 * init_data points to array of regulator_init structures
259 * coming from the board-evm file.
262 init_data
= tps_board
->tps6507x_ts_init_data
;
264 tsc
= kzalloc(sizeof(struct tps6507x_ts
), GFP_KERNEL
);
266 dev_err(tps6507x_dev
->dev
, "failed to allocate driver data\n");
271 tps6507x_dev
->ts
= tsc
;
272 tsc
->mfd
= tps6507x_dev
;
273 tsc
->dev
= tps6507x_dev
->dev
;
274 input_dev
= input_allocate_device();
276 dev_err(tsc
->dev
, "Failed to allocate input device.\n");
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
);
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);
288 input_dev
->name
= "TPS6507x Touchscreen";
289 input_dev
->id
.bustype
= BUS_I2C
;
290 input_dev
->dev
.parent
= tsc
->dev
;
292 snprintf(tsc
->phys
, sizeof(tsc
->phys
),
293 "%s/input0", dev_name(tsc
->dev
));
294 input_dev
->phys
= tsc
->phys
;
296 dev_dbg(tsc
->dev
, "device: %s\n", input_dev
->phys
);
298 input_set_drvdata(input_dev
, tsc
);
300 tsc
->input_dev
= input_dev
;
302 INIT_DELAYED_WORK(&tsc
->work
, tps6507x_ts_handler
);
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
;
312 tsc
->poll_period
= TSC_DEFAULT_POLL_PERIOD
;
313 tsc
->min_pressure
= TPS_DEFAULT_MIN_PRESSURE
;
316 error
= tps6507x_adc_standby(tsc
);
320 error
= input_register_device(input_dev
);
324 schd
= schedule_delayed_work(&tsc
->work
,
325 msecs_to_jiffies(tsc
->poll_period
));
331 dev_err(tsc
->dev
, "schedule failed");
334 platform_set_drvdata(pdev
, tps6507x_dev
);
339 cancel_delayed_work_sync(&tsc
->work
);
340 input_free_device(input_dev
);
343 tps6507x_dev
->ts
= NULL
;
348 static int tps6507x_ts_remove(struct platform_device
*pdev
)
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
;
354 cancel_delayed_work_sync(&tsc
->work
);
356 input_unregister_device(input_dev
);
358 tps6507x_dev
->ts
= NULL
;
364 static struct platform_driver tps6507x_ts_driver
= {
366 .name
= "tps6507x-ts",
367 .owner
= THIS_MODULE
,
369 .probe
= tps6507x_ts_probe
,
370 .remove
= tps6507x_ts_remove
,
372 module_platform_driver(tps6507x_ts_driver
);
374 MODULE_AUTHOR("Todd Fischer <todd.fischer@ridgerun.com>");
375 MODULE_DESCRIPTION("TPS6507x - TouchScreen driver");
376 MODULE_LICENSE("GPL v2");
377 MODULE_ALIAS("platform:tps6507x-ts");