- 根目录:
- drivers
- input
- touchscreen
- pixcir_i2c_ts.c
/*
* Driver for Pixcir I2C touchscreen controllers.
*
* Copyright (C) 2010-2011 Pixcir, Inc.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program 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/delay.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/input/pixcir_ts.h>
#include <linux/gpio.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/of_device.h>
#define PIXCIR_MAX_SLOTS 5 /* Max fingers supported by driver */
struct pixcir_i2c_ts_data {
struct i2c_client *client;
struct input_dev *input;
const struct pixcir_ts_platform_data *pdata;
bool running;
int max_fingers; /* Max fingers supported in this instance */
};
struct pixcir_touch {
int x;
int y;
int id;
};
struct pixcir_report_data {
int num_touches;
struct pixcir_touch touches[PIXCIR_MAX_SLOTS];
};
static void pixcir_ts_parse(struct pixcir_i2c_ts_data *tsdata,
struct pixcir_report_data *report)
{
u8 rdbuf[2 + PIXCIR_MAX_SLOTS * 5];
u8 wrbuf[1] = { 0 };
u8 *bufptr;
u8 touch;
int ret, i;
int readsize;
const struct pixcir_i2c_chip_data *chip = &tsdata->pdata->chip;
memset(report, 0, sizeof(struct pixcir_report_data));
i = chip->has_hw_ids ? 1 : 0;
readsize = 2 + tsdata->max_fingers * (4 + i);
if (readsize > sizeof(rdbuf))
readsize = sizeof(rdbuf);
ret = i2c_master_send(tsdata->client, wrbuf, sizeof(wrbuf));
if (ret != sizeof(wrbuf)) {
dev_err(&tsdata->client->dev,
"%s: i2c_master_send failed(), ret=%d\n",
__func__, ret);
return;
}
ret = i2c_master_recv(tsdata->client, rdbuf, readsize);
if (ret != sizeof(rdbuf)) {
dev_err(&tsdata->client->dev,
"%s: i2c_master_recv failed(), ret=%d\n",
__func__, ret);
return;
}
touch = rdbuf[0] & 0x7;
if (touch > tsdata->max_fingers)
touch = tsdata->max_fingers;
report->num_touches = touch;
bufptr = &rdbuf[2];
for (i = 0; i < touch; i++) {
report->touches[i].x = (bufptr[1] << 8) | bufptr[0];
report->touches[i].y = (bufptr[3] << 8) | bufptr[2];
if (chip->has_hw_ids) {
report->touches[i].id = bufptr[4];
bufptr = bufptr + 5;
} else {
bufptr = bufptr + 4;
}
}
}
static void pixcir_ts_report(struct pixcir_i2c_ts_data *ts,
struct pixcir_report_data *report)
{
struct input_mt_pos pos[PIXCIR_MAX_SLOTS];
int slots[PIXCIR_MAX_SLOTS];
struct pixcir_touch *touch;
int n, i, slot;
struct device *dev = &ts->client->dev;
const struct pixcir_i2c_chip_data *chip = &ts->pdata->chip;
n = report->num_touches;
if (n > PIXCIR_MAX_SLOTS)
n = PIXCIR_MAX_SLOTS;
if (!chip->has_hw_ids) {
for (i = 0; i < n; i++) {
touch = &report->touches[i];
pos[i].x = touch->x;
pos[i].y = touch->y;
}
input_mt_assign_slots(ts->input, slots, pos, n, 0);
}
for (i = 0; i < n; i++) {
touch = &report->touches[i];
if (chip->has_hw_ids) {
slot = input_mt_get_slot_by_key(ts->input, touch->id);
if (slot < 0) {
dev_dbg(dev, "no free slot for id 0x%x\n",
touch->id);
continue;
}
} else {
slot = slots[i];
}
input_mt_slot(ts->input, slot);
input_mt_report_slot_state(ts->input,
MT_TOOL_FINGER, true);
input_event(ts->input, EV_ABS, ABS_MT_POSITION_X, touch->x);
input_event(ts->input, EV_ABS, ABS_MT_POSITION_Y, touch->y);
dev_dbg(dev, "%d: slot %d, x %d, y %d\n",
i, slot, touch->x, touch->y);
}
input_mt_sync_frame(ts->input);
input_sync(ts->input);
}
static irqreturn_t pixcir_ts_isr(int irq, void *dev_id)
{
struct pixcir_i2c_ts_data *tsdata = dev_id;
const struct pixcir_ts_platform_data *pdata = tsdata->pdata;
struct pixcir_report_data report;
while (tsdata->running) {
/* parse packet */
pixcir_ts_parse(tsdata, &report);
/* report it */
pixcir_ts_report(tsdata, &report);
if (gpio_get_value(pdata->gpio_attb)) {
if (report.num_touches) {
/*
* Last report with no finger up?
* Do it now then.
*/
input_mt_sync_frame(tsdata->input);
input_sync(tsdata->input);
}
break;
}
msleep(20);
}
return IRQ_HANDLED;
}
static int pixcir_set_power_mode(struct pixcir_i2c_ts_data *ts,
enum pixcir_power_mode mode)
{
struct device *dev = &ts->client->dev;
int ret;
ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_POWER_MODE);
if (ret < 0) {
dev_err(dev, "%s: can't read reg 0x%x : %d\n",
__func__, PIXCIR_REG_POWER_MODE, ret);
return ret;
}
ret &= ~PIXCIR_POWER_MODE_MASK;
ret |= mode;
/* Always AUTO_IDLE */
ret |= PIXCIR_POWER_ALLOW_IDLE;
ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_POWER_MODE, ret);
if (ret < 0) {
dev_err(dev, "%s: can't write reg 0x%x : %d\n",
__func__, PIXCIR_REG_POWER_MODE, ret);
return ret;
}
return 0;
}
/*
* Set the interrupt mode for the device i.e. ATTB line behaviour
*
* @polarity : 1 for active high, 0 for active low.
*/
static int pixcir_set_int_mode(struct pixcir_i2c_ts_data *ts,
enum pixcir_int_mode mode, bool polarity)
{
struct device *dev = &ts->client->dev;
int ret;
ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_INT_MODE);
if (ret < 0) {
dev_err(dev, "%s: can't read reg 0x%x : %d\n",
__func__, PIXCIR_REG_INT_MODE, ret);
return ret;
}
ret &= ~PIXCIR_INT_MODE_MASK;
ret |= mode;
if (polarity)
ret |= PIXCIR_INT_POL_HIGH;
else
ret &= ~PIXCIR_INT_POL_HIGH;
ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_INT_MODE, ret);
if (ret < 0) {
dev_err(dev, "%s: can't write reg 0x%x : %d\n",
__func__, PIXCIR_REG_INT_MODE, ret);
return ret;
}
return 0;
}
/*
* Enable/disable interrupt generation
*/
static int pixcir_int_enable(struct pixcir_i2c_ts_data *ts, bool enable)
{
struct device *dev = &ts->client->dev;
int ret;
ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_INT_MODE);
if (ret < 0) {
dev_err(dev, "%s: can't read reg 0x%x : %d\n",
__func__, PIXCIR_REG_INT_MODE, ret);
return ret;
}
if (enable)
ret |= PIXCIR_INT_ENABLE;
else
ret &= ~PIXCIR_INT_ENABLE;
ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_INT_MODE, ret);
if (ret < 0) {
dev_err(dev, "%s: can't write reg 0x%x : %d\n",
__func__, PIXCIR_REG_INT_MODE, ret);
return ret;
}
return 0;
}
static int pixcir_start(struct pixcir_i2c_ts_data *ts)
{
struct device *dev = &ts->client->dev;
int error;
/* LEVEL_TOUCH interrupt with active low polarity */
error = pixcir_set_int_mode(ts, PIXCIR_INT_LEVEL_TOUCH, 0);
if (error) {
dev_err(dev, "Failed to set interrupt mode: %d\n", error);
return error;
}
ts->running = true;
mb(); /* Update status before IRQ can fire */
/* enable interrupt generation */
error = pixcir_int_enable(ts, true);
if (error) {
dev_err(dev, "Failed to enable interrupt generation: %d\n",
error);
return error;
}
return 0;
}
static int pixcir_stop(struct pixcir_i2c_ts_data *ts)
{
int error;
/* Disable interrupt generation */
error = pixcir_int_enable(ts, false);
if (error) {
dev_err(&ts->client->dev,
"Failed to disable interrupt generation: %d\n",
error);
return error;
}
/* Exit ISR if running, no more report parsing */
ts->running = false;
mb(); /* update status before we synchronize irq */
/* Wait till running ISR is complete */
synchronize_irq(ts->client->irq);
return 0;
}
static int pixcir_input_open(struct input_dev *dev)
{
struct pixcir_i2c_ts_data *ts = input_get_drvdata(dev);
return pixcir_start(ts);
}
static void pixcir_input_close(struct input_dev *dev)
{
struct pixcir_i2c_ts_data *ts = input_get_drvdata(dev);
pixcir_stop(ts);
}
static int __maybe_unused pixcir_i2c_ts_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct pixcir_i2c_ts_data *ts = i2c_get_clientdata(client);
struct input_dev *input = ts->input;
int ret = 0;
mutex_lock(&input->mutex);
if (device_may_wakeup(&client->dev)) {
if (!input->users) {
ret = pixcir_start(ts);
if (ret) {
dev_err(dev, "Failed to start\n");
goto unlock;
}
}
enable_irq_wake(client->irq);
} else if (input->users) {
ret = pixcir_stop(ts);
}
unlock:
mutex_unlock(&input->mutex);
return ret;
}
static int __maybe_unused pixcir_i2c_ts_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct pixcir_i2c_ts_data *ts = i2c_get_clientdata(client);
struct input_dev *input = ts->input;
int ret = 0;
mutex_lock(&input->mutex);
if (device_may_wakeup(&client->dev)) {
disable_irq_wake(client->irq);
if (!input->users) {
ret = pixcir_stop(ts);
if (ret) {
dev_err(dev, "Failed to stop\n");
goto unlock;
}
}
} else if (input->users) {
ret = pixcir_start(ts);
}
unlock:
mutex_unlock(&input->mutex);
return ret;
}
static SIMPLE_DEV_PM_OPS(pixcir_dev_pm_ops,
pixcir_i2c_ts_suspend, pixcir_i2c_ts_resume);
#ifdef CONFIG_OF
static const struct of_device_id pixcir_of_match[];
static struct pixcir_ts_platform_data *pixcir_parse_dt(struct device *dev)
{
struct pixcir_ts_platform_data *pdata;
struct device_node *np = dev->of_node;
const struct of_device_id *match;
match = of_match_device(of_match_ptr(pixcir_of_match), dev);
if (!match)
return ERR_PTR(-EINVAL);
pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return ERR_PTR(-ENOMEM);
pdata->chip = *(const struct pixcir_i2c_chip_data *)match->data;
pdata->gpio_attb = of_get_named_gpio(np, "attb-gpio", 0);
/* gpio_attb validity is checked in probe */
if (of_property_read_u32(np, "touchscreen-size-x", &pdata->x_max)) {
dev_err(dev, "Failed to get touchscreen-size-x property\n");
return ERR_PTR(-EINVAL);
}
pdata->x_max -= 1;
if (of_property_read_u32(np, "touchscreen-size-y", &pdata->y_max)) {
dev_err(dev, "Failed to get touchscreen-size-y property\n");
return ERR_PTR(-EINVAL);
}
pdata->y_max -= 1;
dev_dbg(dev, "%s: x %d, y %d, gpio %d\n", __func__,
pdata->x_max + 1, pdata->y_max + 1, pdata->gpio_attb);
return pdata;
}
#else
static struct pixcir_ts_platform_data *pixcir_parse_dt(struct device *dev)
{
return ERR_PTR(-EINVAL);
}
#endif
static int pixcir_i2c_ts_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
const struct pixcir_ts_platform_data *pdata =
dev_get_platdata(&client->dev);
struct device *dev = &client->dev;
struct device_node *np = dev->of_node;
struct pixcir_i2c_ts_data *tsdata;
struct input_dev *input;
int error;
if (np && !pdata) {
pdata = pixcir_parse_dt(dev);
if (IS_ERR(pdata))
return PTR_ERR(pdata);
}
if (!pdata) {
dev_err(&client->dev, "platform data not defined\n");
return -EINVAL;
}
if (!gpio_is_valid(pdata->gpio_attb)) {
dev_err(dev, "Invalid gpio_attb in pdata\n");
return -EINVAL;
}
if (!pdata->chip.max_fingers) {
dev_err(dev, "Invalid max_fingers in pdata\n");
return -EINVAL;
}
tsdata = devm_kzalloc(dev, sizeof(*tsdata), GFP_KERNEL);
if (!tsdata)
return -ENOMEM;
input = devm_input_allocate_device(dev);
if (!input) {
dev_err(dev, "Failed to allocate input device\n");
return -ENOMEM;
}
tsdata->client = client;
tsdata->input = input;
tsdata->pdata = pdata;
input->name = client->name;
input->id.bustype = BUS_I2C;
input->open = pixcir_input_open;
input->close = pixcir_input_close;
input->dev.parent = &client->dev;
__set_bit(EV_KEY, input->evbit);
__set_bit(EV_ABS, input->evbit);
__set_bit(BTN_TOUCH, input->keybit);
input_set_abs_params(input, ABS_X, 0, pdata->x_max, 0, 0);
input_set_abs_params(input, ABS_Y, 0, pdata->y_max, 0, 0);
input_set_abs_params(input, ABS_MT_POSITION_X, 0, pdata->x_max, 0, 0);
input_set_abs_params(input, ABS_MT_POSITION_Y, 0, pdata->y_max, 0, 0);
tsdata->max_fingers = tsdata->pdata->chip.max_fingers;
if (tsdata->max_fingers > PIXCIR_MAX_SLOTS) {
tsdata->max_fingers = PIXCIR_MAX_SLOTS;
dev_info(dev, "Limiting maximum fingers to %d\n",
tsdata->max_fingers);
}
error = input_mt_init_slots(input, tsdata->max_fingers,
INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
if (error) {
dev_err(dev, "Error initializing Multi-Touch slots\n");
return error;
}
input_set_drvdata(input, tsdata);
error = devm_gpio_request_one(dev, pdata->gpio_attb,
GPIOF_DIR_IN, "pixcir_i2c_attb");
if (error) {
dev_err(dev, "Failed to request ATTB gpio\n");
return error;
}
error = devm_request_threaded_irq(dev, client->irq, NULL, pixcir_ts_isr,
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
client->name, tsdata);
if (error) {
dev_err(dev, "failed to request irq %d\n", client->irq);
return error;
}
/* Always be in IDLE mode to save power, device supports auto wake */
error = pixcir_set_power_mode(tsdata, PIXCIR_POWER_IDLE);
if (error) {
dev_err(dev, "Failed to set IDLE mode\n");
return error;
}
/* Stop device till opened */
error = pixcir_stop(tsdata);
if (error)
return error;
error = input_register_device(input);
if (error)
return error;
i2c_set_clientdata(client, tsdata);
device_init_wakeup(&client->dev, 1);
return 0;
}
static int pixcir_i2c_ts_remove(struct i2c_client *client)
{
device_init_wakeup(&client->dev, 0);
return 0;
}
static const struct i2c_device_id pixcir_i2c_ts_id[] = {
{ "pixcir_ts", 0 },
{ "pixcir_tangoc", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, pixcir_i2c_ts_id);
#ifdef CONFIG_OF
static const struct pixcir_i2c_chip_data pixcir_ts_data = {
.max_fingers = 2,
/* no hw id support */
};
static const struct pixcir_i2c_chip_data pixcir_tangoc_data = {
.max_fingers = 5,
.has_hw_ids = true,
};
static const struct of_device_id pixcir_of_match[] = {
{ .compatible = "pixcir,pixcir_ts", .data = &pixcir_ts_data },
{ .compatible = "pixcir,pixcir_tangoc", .data = &pixcir_tangoc_data },
{ }
};
MODULE_DEVICE_TABLE(of, pixcir_of_match);
#endif
static struct i2c_driver pixcir_i2c_ts_driver = {
.driver = {
.owner = THIS_MODULE,
.name = "pixcir_ts",
.pm = &pixcir_dev_pm_ops,
.of_match_table = of_match_ptr(pixcir_of_match),
},
.probe = pixcir_i2c_ts_probe,
.remove = pixcir_i2c_ts_remove,
.id_table = pixcir_i2c_ts_id,
};
module_i2c_driver(pixcir_i2c_ts_driver);
MODULE_AUTHOR("Jianchun Bian <jcbian@pixcir.com.cn>, Dequan Meng <dqmeng@pixcir.com.cn>");
MODULE_DESCRIPTION("Pixcir I2C Touchscreen Driver");
MODULE_LICENSE("GPL");