--- /dev/null
+/*
+ * drivers/input/touchscreen/tsc2007.c
+ *
+ * Copyright (c) 2008 MtekVision Co., Ltd.
+ * Kwangwoo Lee <kwlee@mtekvision.com>
+ *
+ * Using code from:
+ * - ads7846.c
+ * Copyright (c) 2005 David Brownell
+ * Copyright (c) 2006 Nokia Corporation
+ * - corgi_ts.c
+ * Copyright (C) 2004-2005 Richard Purdie
+ * - omap_ts.[hc], ads7846.h, ts_osk.c
+ * Copyright (C) 2002 MontaVista Software
+ * Copyright (C) 2004 Texas Instruments
+ * Copyright (C) 2005 Dirk Behme
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/hrtimer.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/i2c.h>
+#include <linux/i2c/tsc2007.h>
+
+#define TS_POLL_DELAY (10 * 1000) /* ns delay before the first sample */
+#define TS_POLL_PERIOD (5 * 1000) /* ns delay between samples */
+
+#define TSC2007_MEASURE_TEMP0 (0x0 << 4)
+#define TSC2007_MEASURE_AUX (0x2 << 4)
+#define TSC2007_MEASURE_TEMP1 (0x4 << 4)
+#define TSC2007_ACTIVATE_XN (0x8 << 4)
+#define TSC2007_ACTIVATE_YN (0x9 << 4)
+#define TSC2007_ACTIVATE_YP_XN (0xa << 4)
+#define TSC2007_SETUP (0xb << 4)
+#define TSC2007_MEASURE_X (0xc << 4)
+#define TSC2007_MEASURE_Y (0xd << 4)
+#define TSC2007_MEASURE_Z1 (0xe << 4)
+#define TSC2007_MEASURE_Z2 (0xf << 4)
+
+#define TSC2007_POWER_OFF_IRQ_EN (0x0 << 2)
+#define TSC2007_ADC_ON_IRQ_DIS0 (0x1 << 2)
+#define TSC2007_ADC_OFF_IRQ_EN (0x2 << 2)
+#define TSC2007_ADC_ON_IRQ_DIS1 (0x3 << 2)
+
+#define TSC2007_12BIT (0x0 << 1)
+#define TSC2007_8BIT (0x1 << 1)
+
+#define MAX_12BIT ((1 << 12) - 1)
+
+#define ADC_ON_12BIT (TSC2007_12BIT | TSC2007_ADC_ON_IRQ_DIS0)
+
+#define READ_Y (ADC_ON_12BIT | TSC2007_MEASURE_Y)
+#define READ_Z1 (ADC_ON_12BIT | TSC2007_MEASURE_Z1)
+#define READ_Z2 (ADC_ON_12BIT | TSC2007_MEASURE_Z2)
+#define READ_X (ADC_ON_12BIT | TSC2007_MEASURE_X)
+#define PWRDOWN (TSC2007_12BIT | TSC2007_POWER_OFF_IRQ_EN)
+
+struct ts_event {
+ u16 x;
+ u16 y;
+ u16 z1, z2;
+};
+
+struct tsc2007 {
+ struct input_dev *input;
+ char phys[32];
+ struct hrtimer timer;
+ struct ts_event tc;
+
+ struct i2c_client *client;
+
+ spinlock_t lock;
+
+ u16 model;
+ u16 x_plate_ohms;
+
+ unsigned pendown;
+ int irq;
+
+ int (*get_pendown_state)(void);
+ void (*clear_penirq)(void);
+};
+
+static inline int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd)
+{
+ s32 data;
+ u16 val;
+
+ data = i2c_smbus_read_word_data(tsc->client, cmd);
+ if (data < 0) {
+ dev_err(&tsc->client->dev, "i2c io error: %d\n", data);
+ return data;
+ }
+
+ /* The protocol and raw data format from i2c interface:
+ * S Addr Wr [A] Comm [A] S Addr Rd [A] [DataLow] A [DataHigh] NA P
+ * Where DataLow has [D11-D4], DataHigh has [D3-D0 << 4 | Dummy 4bit].
+ */
+ val = swab16(data) >> 4;
+
+ dev_dbg(&tsc->client->dev, "data: 0x%x, val: 0x%x\n", data, val);
+
+ return val;
+}
+
+static void tsc2007_send_event(void *tsc)
+{
+ struct tsc2007 *ts = tsc;
+ u32 rt;
+ u16 x, y, z1, z2;
+
+ x = ts->tc.x;
+ y = ts->tc.y;
+ z1 = ts->tc.z1;
+ z2 = ts->tc.z2;
+
+ /* range filtering */
+ if (x == MAX_12BIT)
+ x = 0;
+
+ if (likely(x && z1)) {
+ /* compute touch pressure resistance using equation #1 */
+ rt = z2;
+ rt -= z1;
+ rt *= x;
+ rt *= ts->x_plate_ohms;
+ rt /= z1;
+ rt = (rt + 2047) >> 12;
+ } else
+ rt = 0;
+
+ /* Sample found inconsistent by debouncing or pressure is beyond
+ * the maximum. Don't report it to user space, repeat at least
+ * once more the measurement
+ */
+ if (rt > MAX_12BIT) {
+ dev_dbg(&ts->client->dev, "ignored pressure %d\n", rt);
+
+ hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
+ HRTIMER_MODE_REL);
+ return;
+ }
+
+ /* NOTE: We can't rely on the pressure to determine the pen down
+ * state, even this controller has a pressure sensor. The pressure
+ * value can fluctuate for quite a while after lifting the pen and
+ * in some cases may not even settle at the expected value.
+ *
+ * The only safe way to check for the pen up condition is in the
+ * timer by reading the pen signal state (it's a GPIO _and_ IRQ).
+ */
+ if (rt) {
+ struct input_dev *input = ts->input;
+
+ if (!ts->pendown) {
+ dev_dbg(&ts->client->dev, "DOWN\n");
+
+ input_report_key(input, BTN_TOUCH, 1);
+ ts->pendown = 1;
+ }
+
+ input_report_abs(input, ABS_X, x);
+ input_report_abs(input, ABS_Y, y);
+ input_report_abs(input, ABS_PRESSURE, rt);
+
+ input_sync(input);
+
+ dev_dbg(&ts->client->dev, "point(%4d,%4d), pressure (%4u)\n",
+ x, y, rt);
+ }
+
+ hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
+ HRTIMER_MODE_REL);
+}
+
+static int tsc2007_read_values(struct tsc2007 *tsc)
+{
+ /* y- still on; turn on only y+ (and ADC) */
+ tsc->tc.y = tsc2007_xfer(tsc, READ_Y);
+
+ /* turn y- off, x+ on, then leave in lowpower */
+ tsc->tc.x = tsc2007_xfer(tsc, READ_X);
+
+ /* turn y+ off, x- on; we'll use formula #1 */
+ tsc->tc.z1 = tsc2007_xfer(tsc, READ_Z1);
+ tsc->tc.z2 = tsc2007_xfer(tsc, READ_Z2);
+
+ /* power down */
+ tsc2007_xfer(tsc, PWRDOWN);
+
+ return 0;
+}
+
+static enum hrtimer_restart tsc2007_timer(struct hrtimer *handle)
+{
+ struct tsc2007 *ts = container_of(handle, struct tsc2007, timer);
+
+ spin_lock_irq(&ts->lock);
+
+ if (unlikely(!ts->get_pendown_state() && ts->pendown)) {
+ struct input_dev *input = ts->input;
+
+ dev_dbg(&ts->client->dev, "UP\n");
+
+ input_report_key(input, BTN_TOUCH, 0);
+ input_report_abs(input, ABS_PRESSURE, 0);
+ input_sync(input);
+
+ ts->pendown = 0;
+ enable_irq(ts->irq);
+ } else {
+ /* pen is still down, continue with the measurement */
+ dev_dbg(&ts->client->dev, "pen is still down\n");
+
+ tsc2007_read_values(ts);
+ tsc2007_send_event(ts);
+ }
+
+ spin_unlock_irq(&ts->lock);
+
+ return HRTIMER_NORESTART;
+}
+
+static irqreturn_t tsc2007_irq(int irq, void *handle)
+{
+ struct tsc2007 *ts = handle;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ts->lock, flags);
+
+ if (likely(ts->get_pendown_state())) {
+ disable_irq(ts->irq);
+ hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_DELAY),
+ HRTIMER_MODE_REL);
+ }
+
+ if (ts->clear_penirq)
+ ts->clear_penirq();
+
+ spin_unlock_irqrestore(&ts->lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+static int tsc2007_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct tsc2007 *ts;
+ struct tsc2007_platform_data *pdata = pdata = client->dev.platform_data;
+ struct input_dev *input_dev;
+ int err;
+
+ if (!pdata) {
+ dev_err(&client->dev, "platform data is required!\n");
+ return -EINVAL;
+ }
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_READ_WORD_DATA))
+ return -EIO;
+
+ ts = kzalloc(sizeof(struct tsc2007), GFP_KERNEL);
+ input_dev = input_allocate_device();
+ if (!ts || !input_dev) {
+ err = -ENOMEM;
+ goto err_free_mem;
+ }
+
+ ts->client = client;
+ i2c_set_clientdata(client, ts);
+
+ ts->input = input_dev;
+
+ hrtimer_init(&ts->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ ts->timer.function = tsc2007_timer;
+
+ spin_lock_init(&ts->lock);
+
+ ts->model = pdata->model;
+ ts->x_plate_ohms = pdata->x_plate_ohms;
+ ts->get_pendown_state = pdata->get_pendown_state;
+ ts->clear_penirq = pdata->clear_penirq;
+
+ pdata->init_platform_hw();
+
+ snprintf(ts->phys, sizeof(ts->phys), "%s/input0", client->dev.bus_id);
+
+ input_dev->name = "TSC2007 Touchscreen";
+ input_dev->phys = ts->phys;
+ input_dev->id.bustype = BUS_I2C;
+
+ input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+ input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+
+ input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, 0, 0);
+ input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0);
+ input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0);
+
+ tsc2007_read_values(ts);
+
+ ts->irq = client->irq;
+
+ err = request_irq(ts->irq, tsc2007_irq, 0,
+ client->dev.driver->name, ts);
+ if (err < 0) {
+ dev_err(&client->dev, "irq %d busy?\n", ts->irq);
+ goto err_free_mem;
+ }
+
+ err = input_register_device(input_dev);
+ if (err)
+ goto err_free_irq;
+
+ dev_info(&client->dev, "registered with irq (%d)\n", ts->irq);
+
+ return 0;
+
+ err_free_irq:
+ free_irq(ts->irq, ts);
+ hrtimer_cancel(&ts->timer);
+ err_free_mem:
+ input_free_device(input_dev);
+ kfree(ts);
+ return err;
+}
+
+static int tsc2007_remove(struct i2c_client *client)
+{
+ struct tsc2007 *ts = i2c_get_clientdata(client);
+ struct tsc2007_platform_data *pdata;
+
+ pdata = client->dev.platform_data;
+ pdata->exit_platform_hw();
+
+ free_irq(ts->irq, ts);
+ hrtimer_cancel(&ts->timer);
+ input_unregister_device(ts->input);
+ kfree(ts);
+
+ return 0;
+}
+
+static struct i2c_device_id tsc2007_idtable[] = {
+ { "tsc2007", 0 },
+ { }
+};
+
+MODULE_DEVICE_TABLE(i2c, tsc2007_idtable);
+
+static struct i2c_driver tsc2007_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "tsc2007"
+ },
+ .id_table = tsc2007_idtable,
+ .probe = tsc2007_probe,
+ .remove = tsc2007_remove,
+};
+
+static int __init tsc2007_init(void)
+{
+ return i2c_add_driver(&tsc2007_driver);
+}
+
+static void __exit tsc2007_exit(void)
+{
+ i2c_del_driver(&tsc2007_driver);
+}
+
+module_init(tsc2007_init);
+module_exit(tsc2007_exit);
+
+MODULE_AUTHOR("Kwangwoo Lee <kwlee@mtekvision.com>");
+MODULE_DESCRIPTION("TSC2007 TouchScreen Driver");
+MODULE_LICENSE("GPL");
projects / linux-2.6-omap-h63xx.git / commitdiff