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path: root/drivers/input/touchscreen/eeti_ts.c
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Diffstat (limited to 'drivers/input/touchscreen/eeti_ts.c')
-rw-r--r--drivers/input/touchscreen/eeti_ts.c286
1 files changed, 286 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/eeti_ts.c b/drivers/input/touchscreen/eeti_ts.c
new file mode 100644
index 00000000000..3ab92222a52
--- /dev/null
+++ b/drivers/input/touchscreen/eeti_ts.c
@@ -0,0 +1,286 @@
+/*
+ * Touch Screen driver for EETI's I2C connected touch screen panels
+ * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
+ *
+ * See EETI's software guide for the protocol specification:
+ * http://home.eeti.com.tw/web20/eg/guide.htm
+ *
+ * Based on migor_ts.c
+ * Copyright (c) 2008 Magnus Damm
+ * Copyright (c) 2007 Ujjwal Pande <ujjwal@kenati.com>
+ *
+ * This file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This file is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/kernel.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/i2c.h>
+#include <linux/timer.h>
+#include <linux/gpio.h>
+
+static int flip_x;
+module_param(flip_x, bool, 0644);
+MODULE_PARM_DESC(flip_x, "flip x coordinate");
+
+static int flip_y;
+module_param(flip_y, bool, 0644);
+MODULE_PARM_DESC(flip_y, "flip y coordinate");
+
+struct eeti_ts_priv {
+ struct i2c_client *client;
+ struct input_dev *input;
+ struct work_struct work;
+ struct mutex mutex;
+ int irq;
+};
+
+#define EETI_TS_BITDEPTH (11)
+#define EETI_MAXVAL ((1 << (EETI_TS_BITDEPTH + 1)) - 1)
+
+#define REPORT_BIT_PRESSED (1 << 0)
+#define REPORT_BIT_AD0 (1 << 1)
+#define REPORT_BIT_AD1 (1 << 2)
+#define REPORT_BIT_HAS_PRESSURE (1 << 6)
+#define REPORT_RES_BITS(v) (((v) >> 1) + EETI_TS_BITDEPTH)
+
+static void eeti_ts_read(struct work_struct *work)
+{
+ char buf[6];
+ unsigned int x, y, res, pressed, to = 100;
+ struct eeti_ts_priv *priv =
+ container_of(work, struct eeti_ts_priv, work);
+
+ mutex_lock(&priv->mutex);
+
+ while (!gpio_get_value(irq_to_gpio(priv->irq)) && --to)
+ i2c_master_recv(priv->client, buf, sizeof(buf));
+
+ if (!to) {
+ dev_err(&priv->client->dev,
+ "unable to clear IRQ - line stuck?\n");
+ goto out;
+ }
+
+ /* drop non-report packets */
+ if (!(buf[0] & 0x80))
+ goto out;
+
+ pressed = buf[0] & REPORT_BIT_PRESSED;
+ res = REPORT_RES_BITS(buf[0] & (REPORT_BIT_AD0 | REPORT_BIT_AD1));
+ x = buf[2] | (buf[1] << 8);
+ y = buf[4] | (buf[3] << 8);
+
+ /* fix the range to 11 bits */
+ x >>= res - EETI_TS_BITDEPTH;
+ y >>= res - EETI_TS_BITDEPTH;
+
+ if (flip_x)
+ x = EETI_MAXVAL - x;
+
+ if (flip_y)
+ y = EETI_MAXVAL - y;
+
+ if (buf[0] & REPORT_BIT_HAS_PRESSURE)
+ input_report_abs(priv->input, ABS_PRESSURE, buf[5]);
+
+ input_report_abs(priv->input, ABS_X, x);
+ input_report_abs(priv->input, ABS_Y, y);
+ input_report_key(priv->input, BTN_TOUCH, !!pressed);
+ input_sync(priv->input);
+
+out:
+ mutex_unlock(&priv->mutex);
+}
+
+static irqreturn_t eeti_ts_isr(int irq, void *dev_id)
+{
+ struct eeti_ts_priv *priv = dev_id;
+
+ /* postpone I2C transactions as we are atomic */
+ schedule_work(&priv->work);
+
+ return IRQ_HANDLED;
+}
+
+static int eeti_ts_open(struct input_dev *dev)
+{
+ struct eeti_ts_priv *priv = input_get_drvdata(dev);
+
+ enable_irq(priv->irq);
+
+ /* Read the events once to arm the IRQ */
+ eeti_ts_read(&priv->work);
+
+ return 0;
+}
+
+static void eeti_ts_close(struct input_dev *dev)
+{
+ struct eeti_ts_priv *priv = input_get_drvdata(dev);
+
+ disable_irq(priv->irq);
+ cancel_work_sync(&priv->work);
+}
+
+static int __devinit eeti_ts_probe(struct i2c_client *client,
+ const struct i2c_device_id *idp)
+{
+ struct eeti_ts_priv *priv;
+ struct input_dev *input;
+ int err = -ENOMEM;
+
+ /* In contrast to what's described in the datasheet, there seems
+ * to be no way of probing the presence of that device using I2C
+ * commands. So we need to blindly believe it is there, and wait
+ * for interrupts to occur. */
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv) {
+ dev_err(&client->dev, "failed to allocate driver data\n");
+ goto err0;
+ }
+
+ mutex_init(&priv->mutex);
+ input = input_allocate_device();
+
+ if (!input) {
+ dev_err(&client->dev, "Failed to allocate input device.\n");
+ goto err1;
+ }
+
+ input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+ input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+
+ input_set_abs_params(input, ABS_X, 0, EETI_MAXVAL, 0, 0);
+ input_set_abs_params(input, ABS_Y, 0, EETI_MAXVAL, 0, 0);
+ input_set_abs_params(input, ABS_PRESSURE, 0, 0xff, 0, 0);
+
+ input->name = client->name;
+ input->id.bustype = BUS_I2C;
+ input->dev.parent = &client->dev;
+ input->open = eeti_ts_open;
+ input->close = eeti_ts_close;
+
+ priv->client = client;
+ priv->input = input;
+ priv->irq = client->irq;
+
+ INIT_WORK(&priv->work, eeti_ts_read);
+ i2c_set_clientdata(client, priv);
+ input_set_drvdata(input, priv);
+
+ err = input_register_device(input);
+ if (err)
+ goto err1;
+
+ err = request_irq(priv->irq, eeti_ts_isr, IRQF_TRIGGER_FALLING,
+ client->name, priv);
+ if (err) {
+ dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
+ goto err2;
+ }
+
+ /* Disable the irq for now. It will be enabled once the input device
+ * is opened. */
+ disable_irq(priv->irq);
+
+ device_init_wakeup(&client->dev, 0);
+ return 0;
+
+err2:
+ input_unregister_device(input);
+ input = NULL; /* so we dont try to free it below */
+err1:
+ input_free_device(input);
+ i2c_set_clientdata(client, NULL);
+ kfree(priv);
+err0:
+ return err;
+}
+
+static int __devexit eeti_ts_remove(struct i2c_client *client)
+{
+ struct eeti_ts_priv *priv = i2c_get_clientdata(client);
+
+ free_irq(priv->irq, priv);
+ input_unregister_device(priv->input);
+ i2c_set_clientdata(client, NULL);
+ kfree(priv);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int eeti_ts_suspend(struct i2c_client *client, pm_message_t mesg)
+{
+ struct eeti_ts_priv *priv = i2c_get_clientdata(client);
+
+ if (device_may_wakeup(&client->dev))
+ enable_irq_wake(priv->irq);
+
+ return 0;
+}
+
+static int eeti_ts_resume(struct i2c_client *client)
+{
+ struct eeti_ts_priv *priv = i2c_get_clientdata(client);
+
+ if (device_may_wakeup(&client->dev))
+ disable_irq_wake(priv->irq);
+
+ return 0;
+}
+#else
+#define eeti_ts_suspend NULL
+#define eeti_ts_resume NULL
+#endif
+
+static const struct i2c_device_id eeti_ts_id[] = {
+ { "eeti_ts", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, eeti_ts_id);
+
+static struct i2c_driver eeti_ts_driver = {
+ .driver = {
+ .name = "eeti_ts",
+ },
+ .probe = eeti_ts_probe,
+ .remove = __devexit_p(eeti_ts_remove),
+ .suspend = eeti_ts_suspend,
+ .resume = eeti_ts_resume,
+ .id_table = eeti_ts_id,
+};
+
+static int __init eeti_ts_init(void)
+{
+ return i2c_add_driver(&eeti_ts_driver);
+}
+
+static void __exit eeti_ts_exit(void)
+{
+ i2c_del_driver(&eeti_ts_driver);
+}
+
+MODULE_DESCRIPTION("EETI Touchscreen driver");
+MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
+MODULE_LICENSE("GPL");
+
+module_init(eeti_ts_init);
+module_exit(eeti_ts_exit);
+