diff options
Diffstat (limited to 'drivers/input/touchscreen/eeti_ts.c')
| -rw-r--r-- | drivers/input/touchscreen/eeti_ts.c | 286 |
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); + |