2 * TSC2005 touchscreen driver
4 * Copyright (C) 2006-2008 Nokia Corporation
6 * Author: Lauri Leukkunen <lauri.leukkunen@nokia.com>
7 * based on TSC2301 driver by Klaus K. Pedersen <klaus.k.pedersen@nokia.com>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/input.h>
28 #include <linux/interrupt.h>
29 #include <linux/delay.h>
30 #include <linux/spi/spi.h>
32 #ifdef CONFIG_ARCH_OMAP
33 #include <asm/arch/gpio.h>
36 #include <linux/spi/tsc2005.h>
39 * The touchscreen interface operates as follows:
42 * Request access to GPIO103 (DAV)
43 * tsc2005_dav_irq_handler will trigger when DAV line goes down
45 * 1) Pen is pressed against touchscreeen
46 * 2) TSC2005 performs AD conversion
47 * 3) After the conversion is done TSC2005 drives DAV line down
48 * 4) GPIO IRQ is received and tsc2005_dav_irq_handler is called
49 * 5) tsc2005_ts_irq_handler queues up an spi transfer to fetch
50 * the x, y, z1, z2 values
51 * 6) tsc2005_ts_rx() reports coordinates to input layer and
52 * sets up tsc2005_ts_timer() to be called after TSC2005_TS_SCAN_TIME
53 * 7) When the penup_timer expires, there have not been DAV interrupts
54 * during the last 20ms which means the pen has been lifted.
57 #define TSC2005_VDD_LOWER_27
59 #ifdef TSC2005_VDD_LOWER_27
60 #define TSC2005_HZ (10000000)
62 #define TSC2005_HZ (25000000)
65 #define TSC2005_CMD (0x80)
66 #define TSC2005_REG (0x00)
68 #define TSC2005_CMD_STOP (1)
69 #define TSC2005_CMD_10BIT (0 << 2)
70 #define TSC2005_CMD_12BIT (1 << 2)
72 #define TSC2005_CMD_SCAN_XYZZ (0 << 3)
73 #define TSC2005_CMD_SCAN_XY (1 << 3)
74 #define TSC2005_CMD_SCAN_X (2 << 3)
75 #define TSC2005_CMD_SCAN_Y (3 << 3)
76 #define TSC2005_CMD_SCAN_ZZ (4 << 3)
77 #define TSC2005_CMD_AUX_SINGLE (5 << 3)
78 #define TSC2005_CMD_TEMP1 (6 << 3)
79 #define TSC2005_CMD_TEMP2 (7 << 3)
80 #define TSC2005_CMD_AUX_CONT (8 << 3)
81 #define TSC2005_CMD_TEST_X_CONN (9 << 3)
82 #define TSC2005_CMD_TEST_Y_CONN (10 << 3)
83 /* command 11 reserved */
84 #define TSC2005_CMD_TEST_SHORT (12 << 3)
85 #define TSC2005_CMD_DRIVE_XX (13 << 3)
86 #define TSC2005_CMD_DRIVE_YY (14 << 3)
87 #define TSC2005_CMD_DRIVE_YX (15 << 3)
89 #define TSC2005_REG_X (0 << 3)
90 #define TSC2005_REG_Y (1 << 3)
91 #define TSC2005_REG_Z1 (2 << 3)
92 #define TSC2005_REG_Z2 (3 << 3)
93 #define TSC2005_REG_AUX (4 << 3)
94 #define TSC2005_REG_TEMP1 (5 << 3)
95 #define TSC2005_REG_TEMP2 (6 << 3)
96 #define TSC2005_REG_STATUS (7 << 3)
97 #define TSC2005_REG_AUX_HIGH (8 << 3)
98 #define TSC2005_REG_AUX_LOW (9 << 3)
99 #define TSC2005_REG_TEMP_HIGH (10 << 3)
100 #define TSC2005_REG_TEMP_LOW (11 << 3)
101 #define TSC2005_REG_CFR0 (12 << 3)
102 #define TSC2005_REG_CFR1 (13 << 3)
103 #define TSC2005_REG_CFR2 (14 << 3)
104 #define TSC2005_REG_FUNCTION (15 << 3)
106 #define TSC2005_REG_PND0 (1 << 1)
107 #define TSC2005_REG_READ (0x01)
108 #define TSC2005_REG_WRITE (0x00)
111 #define TSC2005_CFR0_LONGSAMPLING (1)
112 #define TSC2005_CFR0_DETECTINWAIT (1 << 1)
113 #define TSC2005_CFR0_SENSETIME_32US (0)
114 #define TSC2005_CFR0_SENSETIME_96US (1 << 2)
115 #define TSC2005_CFR0_SENSETIME_544US (1 << 3)
116 #define TSC2005_CFR0_SENSETIME_2080US (1 << 4)
117 #define TSC2005_CFR0_SENSETIME_2656US (0x001C)
118 #define TSC2005_CFR0_PRECHARGE_20US (0x0000)
119 #define TSC2005_CFR0_PRECHARGE_84US (0x0020)
120 #define TSC2005_CFR0_PRECHARGE_276US (0x0040)
121 #define TSC2005_CFR0_PRECHARGE_1044US (0x0080)
122 #define TSC2005_CFR0_PRECHARGE_1364US (0x00E0)
123 #define TSC2005_CFR0_STABTIME_0US (0x0000)
124 #define TSC2005_CFR0_STABTIME_100US (0x0100)
125 #define TSC2005_CFR0_STABTIME_500US (0x0200)
126 #define TSC2005_CFR0_STABTIME_1MS (0x0300)
127 #define TSC2005_CFR0_STABTIME_5MS (0x0400)
128 #define TSC2005_CFR0_STABTIME_100MS (0x0700)
129 #define TSC2005_CFR0_CLOCK_4MHZ (0x0000)
130 #define TSC2005_CFR0_CLOCK_2MHZ (0x0800)
131 #define TSC2005_CFR0_CLOCK_1MHZ (0x1000)
132 #define TSC2005_CFR0_RESOLUTION12 (0x2000)
133 #define TSC2005_CFR0_STATUS (0x4000)
134 #define TSC2005_CFR0_PENMODE (0x8000)
136 #define TSC2005_CFR0_INITVALUE (TSC2005_CFR0_STABTIME_1MS | \
137 TSC2005_CFR0_CLOCK_1MHZ | \
138 TSC2005_CFR0_RESOLUTION12 | \
139 TSC2005_CFR0_PRECHARGE_276US | \
140 TSC2005_CFR0_PENMODE)
142 #define TSC2005_CFR1_BATCHDELAY_0MS (0x0000)
143 #define TSC2005_CFR1_BATCHDELAY_1MS (0x0001)
144 #define TSC2005_CFR1_BATCHDELAY_2MS (0x0002)
145 #define TSC2005_CFR1_BATCHDELAY_4MS (0x0003)
146 #define TSC2005_CFR1_BATCHDELAY_10MS (0x0004)
147 #define TSC2005_CFR1_BATCHDELAY_20MS (0x0005)
148 #define TSC2005_CFR1_BATCHDELAY_40MS (0x0006)
149 #define TSC2005_CFR1_BATCHDELAY_100MS (0x0007)
151 #define TSC2005_CFR1_INITVALUE (TSC2005_CFR1_BATCHDELAY_2MS)
153 #define TSC2005_CFR2_MAVE_TEMP (0x0001)
154 #define TSC2005_CFR2_MAVE_AUX (0x0002)
155 #define TSC2005_CFR2_MAVE_Z (0x0004)
156 #define TSC2005_CFR2_MAVE_Y (0x0008)
157 #define TSC2005_CFR2_MAVE_X (0x0010)
158 #define TSC2005_CFR2_AVG_1 (0x0000)
159 #define TSC2005_CFR2_AVG_3 (0x0400)
160 #define TSC2005_CFR2_AVG_7 (0x0800)
161 #define TSC2005_CFR2_MEDIUM_1 (0x0000)
162 #define TSC2005_CFR2_MEDIUM_3 (0x1000)
163 #define TSC2005_CFR2_MEDIUM_7 (0x2000)
164 #define TSC2005_CFR2_MEDIUM_15 (0x3000)
166 #define TSC2005_CFR2_IRQ_DAV (0x4000)
167 #define TSC2005_CFR2_IRQ_PEN (0x8000)
168 #define TSC2005_CFR2_IRQ_PENDAV (0x0000)
170 #define TSC2005_CFR2_INITVALUE (TSC2005_CFR2_IRQ_DAV | \
171 TSC2005_CFR2_MAVE_X | \
172 TSC2005_CFR2_MAVE_Y | \
173 TSC2005_CFR2_MAVE_Z | \
174 TSC2005_CFR2_MEDIUM_15 | \
177 #define MAX_12BIT ((1 << 12) - 1)
179 #define TS_RECT_SIZE 8
180 #define TSC2005_TS_PENUP_TIME 20
182 static const u32 tsc2005_read_reg[] = {
183 (TSC2005_REG | TSC2005_REG_X | TSC2005_REG_READ) << 16,
184 (TSC2005_REG | TSC2005_REG_Y | TSC2005_REG_READ) << 16,
185 (TSC2005_REG | TSC2005_REG_Z1 | TSC2005_REG_READ) << 16,
186 (TSC2005_REG | TSC2005_REG_Z2 | TSC2005_REG_READ) << 16,
188 #define NUM_READ_REGS (sizeof(tsc2005_read_reg)/sizeof(tsc2005_read_reg[0]))
191 struct spi_device *spi;
193 struct input_dev *idev;
195 struct timer_list penup_timer;
199 struct spi_message read_msg;
200 struct spi_transfer read_xfer[NUM_READ_REGS];
201 u32 data[NUM_READ_REGS];
207 /* average accumulators for each component */
229 static void tsc2005_cmd(struct tsc2005 *ts, u8 cmd)
231 u16 data = TSC2005_CMD | TSC2005_CMD_12BIT | cmd;
232 struct spi_message msg;
233 struct spi_transfer xfer = { 0 };
238 xfer.bits_per_word = 8;
240 spi_message_init(&msg);
241 spi_message_add_tail(&xfer, &msg);
242 spi_sync(ts->spi, &msg);
245 static void tsc2005_write(struct tsc2005 *ts, u8 reg, u16 value)
248 struct spi_message msg;
249 struct spi_transfer xfer = { 0 };
251 tx = (TSC2005_REG | reg | TSC2005_REG_PND0 |
252 TSC2005_REG_WRITE) << 16;
258 xfer.bits_per_word = 24;
260 spi_message_init(&msg);
261 spi_message_add_tail(&xfer, &msg);
262 spi_sync(ts->spi, &msg);
265 static void tsc2005_ts_update_pen_state(struct tsc2005 *ts,
266 int x, int y, int pressure)
269 input_report_abs(ts->idev, ABS_X, x);
270 input_report_abs(ts->idev, ABS_Y, y);
271 input_report_abs(ts->idev, ABS_PRESSURE, pressure);
273 input_report_key(ts->idev, BTN_TOUCH, 1);
277 input_report_abs(ts->idev, ABS_PRESSURE, 0);
279 input_report_key(ts->idev, BTN_TOUCH, 0);
284 input_sync(ts->idev);
288 * This function is called by the SPI framework after the coordinates
289 * have been read from TSC2005
291 static void tsc2005_ts_rx(void *arg)
293 struct tsc2005 *ts = arg;
295 int inside_rect, pressure_limit;
296 int x, y, z1, z2, pressure;
298 spin_lock_irqsave(&ts->lock, flags);
305 /* validate pressure and position */
306 if (x > MAX_12BIT || y > MAX_12BIT)
309 /* skip coords if the pressure-components are out of range */
310 if (z1 < 100 || z2 > 4000)
313 /* don't run average on the "pen down" event */
314 if (ts->sample_sent) {
320 if (++ts->sample_cnt < TS_SAMPLES)
323 x = ts->avg_x / TS_SAMPLES;
324 y = ts->avg_y / TS_SAMPLES;
325 z1 = ts->avg_z1 / TS_SAMPLES;
326 z2 = ts->avg_z2 / TS_SAMPLES;
336 pressure = x * (z2 - z1) / z1;
337 pressure = pressure * ts->x_plate_ohm / 4096;
341 pressure_limit = ts->sample_sent? ts->p_max: ts->touch_pressure;
342 if (pressure > pressure_limit)
345 /* discard the event if it still is within the previous rect - unless
346 * if the pressure is harder, but then use previous x,y position */
347 inside_rect = (ts->sample_sent &&
348 x > (int)ts->x - TS_RECT_SIZE &&
349 x < (int)ts->x + TS_RECT_SIZE &&
350 y > (int)ts->y - TS_RECT_SIZE &&
351 y < (int)ts->y + TS_RECT_SIZE);
353 x = ts->x, y = ts->y;
355 if (!inside_rect || pressure < ts->p) {
356 tsc2005_ts_update_pen_state(ts, x, y, pressure);
364 spin_unlock_irqrestore(&ts->lock, flags);
366 /* kick pen up timer - to make sure it expires again(!) */
368 mod_timer(&ts->penup_timer,
369 jiffies + msecs_to_jiffies(TSC2005_TS_PENUP_TIME));
372 static void tsc2005_ts_penup_timer_handler(unsigned long data)
374 struct tsc2005 *ts = (struct tsc2005 *)data;
376 if (ts->sample_sent) {
377 tsc2005_ts_update_pen_state(ts, 0, 0, 0);
383 * This interrupt is called when pen is down and coordinates are
384 * available. That is indicated by a falling edge on DAV line.
386 static irqreturn_t tsc2005_ts_irq_handler(int irq, void *dev_id)
388 struct tsc2005 *ts = dev_id;
395 r = spi_async(ts->spi, &ts->read_msg);
397 dev_err(&ts->spi->dev, "ts: spi_async() failed");
399 /* kick pen up timer */
400 mod_timer(&ts->penup_timer,
401 jiffies + msecs_to_jiffies(TSC2005_TS_PENUP_TIME));
406 static void tsc2005_ts_setup_spi_xfer(struct tsc2005 *ts)
408 struct spi_message *m = &ts->read_msg;
409 struct spi_transfer *x = &ts->read_xfer[0];
414 for (i = 0; i < NUM_READ_REGS; i++, x++) {
415 x->tx_buf = &tsc2005_read_reg[i];
416 x->rx_buf = &ts->data[i];
418 x->bits_per_word = 24;
419 x->cs_change = i < (NUM_READ_REGS - 1);
420 spi_message_add_tail(x, m);
423 m->complete = tsc2005_ts_rx;
427 static ssize_t tsc2005_ts_pen_down_show(struct device *dev,
428 struct device_attribute *attr,
431 struct tsc2005 *tsc = dev_get_drvdata(dev);
433 return sprintf(buf, "%u\n", tsc->pen_down);
436 static DEVICE_ATTR(pen_down, S_IRUGO, tsc2005_ts_pen_down_show, NULL);
438 static int tsc2005_configure(struct tsc2005 *tsc, int flags)
440 tsc2005_write(tsc, TSC2005_REG_CFR0, TSC2005_CFR0_INITVALUE);
441 tsc2005_write(tsc, TSC2005_REG_CFR1, TSC2005_CFR1_INITVALUE);
442 tsc2005_write(tsc, TSC2005_REG_CFR2, TSC2005_CFR2_INITVALUE);
443 tsc2005_cmd(tsc, flags);
448 static void tsc2005_start_scan(struct tsc2005 *tsc)
450 tsc2005_configure(tsc, TSC2005_CMD_SCAN_XYZZ);
453 static void tsc2005_stop_scan(struct tsc2005 *tsc)
455 tsc2005_cmd(tsc, TSC2005_CMD_STOP);
458 /* Must be called with mutex held */
459 static void tsc2005_disable(struct tsc2005 *ts)
461 if (ts->disable_depth++ != 0)
464 disable_irq(ts->irq);
466 /* wait until penup timer expire normally */
469 } while (ts->sample_sent);
471 tsc2005_stop_scan(ts);
474 static void tsc2005_enable(struct tsc2005 *ts)
476 if (--ts->disable_depth != 0)
481 tsc2005_start_scan(ts);
484 static ssize_t tsc2005_disable_show(struct device *dev,
485 struct device_attribute *attr, char *buf)
487 struct tsc2005 *ts = dev_get_drvdata(dev);
489 return sprintf(buf, "%u\n", ts->disabled);
492 static ssize_t tsc2005_disable_store(struct device *dev,
493 struct device_attribute *attr,
494 const char *buf, size_t count)
496 struct tsc2005 *tsc = dev_get_drvdata(dev);
500 i = strict_strtoul(buf, 10, &res);
503 mutex_lock(&tsc->mutex);
504 if (i == tsc->disabled)
509 tsc2005_disable(tsc);
513 mutex_unlock(&tsc->mutex);
517 static DEVICE_ATTR(disable_ts, 0664, tsc2005_disable_show,
518 tsc2005_disable_store);
521 static int __devinit tsc2005_ts_init(struct tsc2005 *ts,
522 struct tsc2005_platform_data *pdata)
524 struct input_dev *idev;
527 int x_fudge, y_fudge, p_fudge;
529 if (pdata->dav_gpio < 0) {
530 dev_err(&ts->spi->dev, "need DAV GPIO");
533 dav_gpio = pdata->dav_gpio;
534 ts->dav_gpio = dav_gpio;
535 dev_dbg(&ts->spi->dev, "TSC2005: DAV GPIO = %d\n", dav_gpio);
537 #ifdef CONFIG_ARCH_OMAP
538 r = omap_request_gpio(dav_gpio);
540 dev_err(&ts->spi->dev, "unable to get DAV GPIO");
543 omap_set_gpio_direction(dav_gpio, 1);
544 ts->irq = OMAP_GPIO_IRQ(dav_gpio);
545 dev_dbg(&ts->spi->dev, "TSC2005: DAV IRQ = %d\n", ts->irq);
547 init_timer(&ts->penup_timer);
548 setup_timer(&ts->penup_timer, tsc2005_ts_penup_timer_handler,
551 spin_lock_init(&ts->lock);
552 mutex_init(&ts->mutex);
554 ts->x_plate_ohm = pdata->ts_x_plate_ohm ? : 280;
555 ts->hw_avg_max = pdata->ts_hw_avg;
556 ts->stab_time = pdata->ts_stab_time;
557 x_max = pdata->ts_x_max ? : 4096;
558 x_fudge = pdata->ts_x_fudge ? : 4;
559 y_max = pdata->ts_y_max ? : 4096;
560 y_fudge = pdata->ts_y_fudge ? : 8;
561 ts->p_max = pdata->ts_pressure_max ? : MAX_12BIT;
562 ts->touch_pressure = pdata->ts_touch_pressure ? : ts->p_max;
563 p_fudge = pdata->ts_pressure_fudge ? : 2;
565 idev = input_allocate_device();
571 idev->name = "TSC2005 touchscreen";
572 snprintf(ts->phys, sizeof(ts->phys), "%s/input-ts",
573 ts->spi->dev.bus_id);
574 idev->phys = ts->phys;
576 idev->evbit[0] = BIT(EV_ABS) | BIT(EV_KEY);
577 idev->absbit[0] = BIT(ABS_X) | BIT(ABS_Y) | BIT(ABS_PRESSURE);
580 tsc2005_ts_setup_spi_xfer(ts);
582 input_set_abs_params(idev, ABS_X, 0, x_max, x_fudge, 0);
583 input_set_abs_params(idev, ABS_Y, 0, y_max, y_fudge, 0);
584 input_set_abs_params(idev, ABS_PRESSURE, 0, ts->p_max, p_fudge, 0);
586 tsc2005_start_scan(ts);
588 r = request_irq(ts->irq, tsc2005_ts_irq_handler,
589 IRQF_TRIGGER_FALLING | IRQF_DISABLED |
590 IRQF_SAMPLE_RANDOM, "tsc2005", ts);
592 dev_err(&ts->spi->dev, "unable to get DAV IRQ");
596 set_irq_wake(ts->irq, 1);
598 r = input_register_device(idev);
600 dev_err(&ts->spi->dev, "can't register touchscreen device\n");
604 /* We can tolerate these failing */
605 if (device_create_file(&ts->spi->dev, &dev_attr_pen_down));
606 if (device_create_file(&ts->spi->dev, &dev_attr_disable_ts));
610 free_irq(ts->irq, ts);
612 tsc2005_stop_scan(ts);
613 input_free_device(idev);
615 #ifdef CONFIG_ARCH_OMAP
616 omap_free_gpio(dav_gpio);
622 static int __devinit tsc2005_probe(struct spi_device *spi)
625 struct tsc2005_platform_data *pdata = spi->dev.platform_data;
629 dev_dbg(&spi->dev, "no platform data?\n");
633 tsc = kzalloc(sizeof(*tsc), GFP_KERNEL);
637 dev_set_drvdata(&spi->dev, tsc);
639 spi->dev.power.power_state = PMSG_ON;
641 spi->mode = SPI_MODE_0;
642 spi->bits_per_word = 8;
643 /* The max speed might've been defined by the board-specific
645 if (!spi->max_speed_hz)
646 spi->max_speed_hz = TSC2005_HZ;
650 r = tsc2005_ts_init(tsc, pdata);
661 static int __devexit tsc2005_remove(struct spi_device *spi)
663 struct tsc2005 *ts = dev_get_drvdata(&spi->dev);
665 mutex_lock(&ts->mutex);
667 mutex_unlock(&ts->mutex);
669 device_remove_file(&ts->spi->dev, &dev_attr_disable_ts);
670 device_remove_file(&ts->spi->dev, &dev_attr_pen_down);
672 free_irq(ts->irq, ts);
673 input_unregister_device(ts->idev);
675 #ifdef CONFIG_ARCH_OMAP
676 omap_free_gpio(ts->dav_gpio);
684 static int tsc2005_suspend(struct spi_device *spi, pm_message_t mesg)
686 struct tsc2005 *ts = dev_get_drvdata(&spi->dev);
688 mutex_lock(&ts->mutex);
690 mutex_unlock(&ts->mutex);
695 static int tsc2005_resume(struct spi_device *spi)
697 struct tsc2005 *ts = dev_get_drvdata(&spi->dev);
699 mutex_lock(&ts->mutex);
701 mutex_unlock(&ts->mutex);
707 static struct spi_driver tsc2005_driver = {
710 .owner = THIS_MODULE,
713 .suspend = tsc2005_suspend,
714 .resume = tsc2005_resume,
716 .probe = tsc2005_probe,
717 .remove = __devexit_p(tsc2005_remove),
720 static int __init tsc2005_init(void)
722 printk(KERN_INFO "TSC2005 driver initializing\n");
724 return spi_register_driver(&tsc2005_driver);
726 module_init(tsc2005_init);
728 static void __exit tsc2005_exit(void)
730 spi_unregister_driver(&tsc2005_driver);
732 module_exit(tsc2005_exit);
734 MODULE_AUTHOR("Lauri Leukkunen <lauri.leukkunen@nokia.com>");
735 MODULE_LICENSE("GPL");
736 MODULE_ALIAS("platform:tsc2005");