| /* |
| * 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> |
| #include <linux/input/eeti_ts.h> |
| #include <linux/slab.h> |
| |
| static bool flip_x; |
| module_param(flip_x, bool, 0644); |
| MODULE_PARM_DESC(flip_x, "flip x coordinate"); |
| |
| static bool 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_gpio, irq, irq_active_high; |
| }; |
| |
| #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 inline int eeti_ts_irq_active(struct eeti_ts_priv *priv) |
| { |
| return gpio_get_value(priv->irq_gpio) == priv->irq_active_high; |
| } |
| |
| 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 (eeti_ts_irq_active(priv) && --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 void eeti_ts_start(struct eeti_ts_priv *priv) |
| { |
| enable_irq(priv->irq); |
| |
| /* Read the events once to arm the IRQ */ |
| eeti_ts_read(&priv->work); |
| } |
| |
| static void eeti_ts_stop(struct eeti_ts_priv *priv) |
| { |
| disable_irq(priv->irq); |
| cancel_work_sync(&priv->work); |
| } |
| |
| static int eeti_ts_open(struct input_dev *dev) |
| { |
| struct eeti_ts_priv *priv = input_get_drvdata(dev); |
| |
| eeti_ts_start(priv); |
| |
| return 0; |
| } |
| |
| static void eeti_ts_close(struct input_dev *dev) |
| { |
| struct eeti_ts_priv *priv = input_get_drvdata(dev); |
| |
| eeti_ts_stop(priv); |
| } |
| |
| static int eeti_ts_probe(struct i2c_client *client, |
| const struct i2c_device_id *idp) |
| { |
| struct eeti_ts_platform_data *pdata = client->dev.platform_data; |
| struct eeti_ts_priv *priv; |
| struct input_dev *input; |
| unsigned int irq_flags; |
| 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_gpio = pdata->irq_gpio; |
| priv->irq = gpio_to_irq(pdata->irq_gpio); |
| |
| err = gpio_request_one(pdata->irq_gpio, GPIOF_IN, client->name); |
| if (err < 0) |
| goto err1; |
| |
| if (pdata) |
| priv->irq_active_high = pdata->irq_active_high; |
| |
| irq_flags = priv->irq_active_high ? |
| IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING; |
| |
| 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 err2; |
| |
| err = request_irq(priv->irq, eeti_ts_isr, irq_flags, |
| client->name, priv); |
| if (err) { |
| dev_err(&client->dev, "Unable to request touchscreen IRQ.\n"); |
| goto err3; |
| } |
| |
| /* |
| * Disable the device for now. It will be enabled once the |
| * input device is opened. |
| */ |
| eeti_ts_stop(priv); |
| |
| device_init_wakeup(&client->dev, 0); |
| return 0; |
| |
| err3: |
| input_unregister_device(input); |
| input = NULL; /* so we dont try to free it below */ |
| err2: |
| gpio_free(pdata->irq_gpio); |
| err1: |
| input_free_device(input); |
| 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); |
| /* |
| * eeti_ts_stop() leaves IRQ disabled. We need to re-enable it |
| * so that device still works if we reload the driver. |
| */ |
| enable_irq(priv->irq); |
| |
| input_unregister_device(priv->input); |
| kfree(priv); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM |
| static int eeti_ts_suspend(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| struct eeti_ts_priv *priv = i2c_get_clientdata(client); |
| struct input_dev *input_dev = priv->input; |
| |
| mutex_lock(&input_dev->mutex); |
| |
| if (input_dev->users) |
| eeti_ts_stop(priv); |
| |
| mutex_unlock(&input_dev->mutex); |
| |
| if (device_may_wakeup(&client->dev)) |
| enable_irq_wake(priv->irq); |
| |
| return 0; |
| } |
| |
| static int eeti_ts_resume(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| struct eeti_ts_priv *priv = i2c_get_clientdata(client); |
| struct input_dev *input_dev = priv->input; |
| |
| if (device_may_wakeup(&client->dev)) |
| disable_irq_wake(priv->irq); |
| |
| mutex_lock(&input_dev->mutex); |
| |
| if (input_dev->users) |
| eeti_ts_start(priv); |
| |
| mutex_unlock(&input_dev->mutex); |
| |
| return 0; |
| } |
| |
| static SIMPLE_DEV_PM_OPS(eeti_ts_pm, eeti_ts_suspend, eeti_ts_resume); |
| #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", |
| #ifdef CONFIG_PM |
| .pm = &eeti_ts_pm, |
| #endif |
| }, |
| .probe = eeti_ts_probe, |
| .remove = eeti_ts_remove, |
| .id_table = eeti_ts_id, |
| }; |
| |
| module_i2c_driver(eeti_ts_driver); |
| |
| MODULE_DESCRIPTION("EETI Touchscreen driver"); |
| MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>"); |
| MODULE_LICENSE("GPL"); |