- 根目录:
- drivers
- input
- touchscreen
- ucb1400_ts.c
/*
* Philips UCB1400 touchscreen driver
*
* Author: Nicolas Pitre
* Created: September 25, 2006
* Copyright: MontaVista Software, Inc.
*
* Spliting done by: Marek Vasut <marek.vasut@gmail.com>
* If something doesn't work and it worked before spliting, e-mail me,
* dont bother Nicolas please ;-)
*
* 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.
*
* This code is heavily based on ucb1x00-*.c copyrighted by Russell King
* covering the UCB1100, UCB1200 and UCB1300.. Support for the UCB1400 has
* been made separate from ucb1x00-core/ucb1x00-ts on Russell's request.
*/
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/input.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/ucb1400.h>
#define UCB1400_TS_POLL_PERIOD 10 /* ms */
static bool adcsync;
static int ts_delay = 55; /* us */
static int ts_delay_pressure; /* us */
/* Switch to interrupt mode. */
static void ucb1400_ts_mode_int(struct ucb1400_ts *ucb)
{
ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
UCB_TS_CR_MODE_INT);
}
/*
* Switch to pressure mode, and read pressure. We don't need to wait
* here, since both plates are being driven.
*/
static unsigned int ucb1400_ts_read_pressure(struct ucb1400_ts *ucb)
{
ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
UCB_TS_CR_TSMX_POW | UCB_TS_CR_TSPX_POW |
UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_GND |
UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
udelay(ts_delay_pressure);
return ucb1400_adc_read(ucb->ac97, UCB_ADC_INP_TSPY, adcsync);
}
/*
* Switch to X position mode and measure Y plate. We switch the plate
* configuration in pressure mode, then switch to position mode. This
* gives a faster response time. Even so, we need to wait about 55us
* for things to stabilise.
*/
static unsigned int ucb1400_ts_read_xpos(struct ucb1400_ts *ucb)
{
ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
udelay(ts_delay);
return ucb1400_adc_read(ucb->ac97, UCB_ADC_INP_TSPY, adcsync);
}
/*
* Switch to Y position mode and measure X plate. We switch the plate
* configuration in pressure mode, then switch to position mode. This
* gives a faster response time. Even so, we need to wait about 55us
* for things to stabilise.
*/
static int ucb1400_ts_read_ypos(struct ucb1400_ts *ucb)
{
ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
UCB_TS_CR_MODE_POS | UCB_TS_CR_BIAS_ENA);
udelay(ts_delay);
return ucb1400_adc_read(ucb->ac97, UCB_ADC_INP_TSPX, adcsync);
}
/*
* Switch to X plate resistance mode. Set MX to ground, PX to
* supply. Measure current.
*/
static unsigned int ucb1400_ts_read_xres(struct ucb1400_ts *ucb)
{
ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
UCB_TS_CR_TSMX_GND | UCB_TS_CR_TSPX_POW |
UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
return ucb1400_adc_read(ucb->ac97, 0, adcsync);
}
/*
* Switch to Y plate resistance mode. Set MY to ground, PY to
* supply. Measure current.
*/
static unsigned int ucb1400_ts_read_yres(struct ucb1400_ts *ucb)
{
ucb1400_reg_write(ucb->ac97, UCB_TS_CR,
UCB_TS_CR_TSMY_GND | UCB_TS_CR_TSPY_POW |
UCB_TS_CR_MODE_PRES | UCB_TS_CR_BIAS_ENA);
return ucb1400_adc_read(ucb->ac97, 0, adcsync);
}
static int ucb1400_ts_pen_up(struct ucb1400_ts *ucb)
{
unsigned short val = ucb1400_reg_read(ucb->ac97, UCB_TS_CR);
return val & (UCB_TS_CR_TSPX_LOW | UCB_TS_CR_TSMX_LOW);
}
static void ucb1400_ts_irq_enable(struct ucb1400_ts *ucb)
{
ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, UCB_IE_TSPX);
ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0);
ucb1400_reg_write(ucb->ac97, UCB_IE_FAL, UCB_IE_TSPX);
}
static void ucb1400_ts_irq_disable(struct ucb1400_ts *ucb)
{
ucb1400_reg_write(ucb->ac97, UCB_IE_FAL, 0);
}
static void ucb1400_ts_report_event(struct input_dev *idev, u16 pressure, u16 x, u16 y)
{
input_report_abs(idev, ABS_X, x);
input_report_abs(idev, ABS_Y, y);
input_report_abs(idev, ABS_PRESSURE, pressure);
input_report_key(idev, BTN_TOUCH, 1);
input_sync(idev);
}
static void ucb1400_ts_event_release(struct input_dev *idev)
{
input_report_abs(idev, ABS_PRESSURE, 0);
input_report_key(idev, BTN_TOUCH, 0);
input_sync(idev);
}
static void ucb1400_clear_pending_irq(struct ucb1400_ts *ucb)
{
unsigned int isr;
isr = ucb1400_reg_read(ucb->ac97, UCB_IE_STATUS);
ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, isr);
ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0);
if (isr & UCB_IE_TSPX)
ucb1400_ts_irq_disable(ucb);
else
dev_dbg(&ucb->ts_idev->dev,
"ucb1400: unexpected IE_STATUS = %#x\n", isr);
}
/*
* A restriction with interrupts exists when using the ucb1400, as
* the codec read/write routines may sleep while waiting for codec
* access completion and uses semaphores for access control to the
* AC97 bus. Therefore the driver is forced to use threaded interrupt
* handler.
*/
static irqreturn_t ucb1400_irq(int irqnr, void *devid)
{
struct ucb1400_ts *ucb = devid;
unsigned int x, y, p;
bool penup;
if (unlikely(irqnr != ucb->irq))
return IRQ_NONE;
ucb1400_clear_pending_irq(ucb);
/* Start with a small delay before checking pendown state */
msleep(UCB1400_TS_POLL_PERIOD);
while (!ucb->stopped && !(penup = ucb1400_ts_pen_up(ucb))) {
ucb1400_adc_enable(ucb->ac97);
x = ucb1400_ts_read_xpos(ucb);
y = ucb1400_ts_read_ypos(ucb);
p = ucb1400_ts_read_pressure(ucb);
ucb1400_adc_disable(ucb->ac97);
ucb1400_ts_report_event(ucb->ts_idev, p, x, y);
wait_event_timeout(ucb->ts_wait, ucb->stopped,
msecs_to_jiffies(UCB1400_TS_POLL_PERIOD));
}
ucb1400_ts_event_release(ucb->ts_idev);
if (!ucb->stopped) {
/* Switch back to interrupt mode. */
ucb1400_ts_mode_int(ucb);
ucb1400_ts_irq_enable(ucb);
}
return IRQ_HANDLED;
}
static void ucb1400_ts_stop(struct ucb1400_ts *ucb)
{
/* Signal IRQ thread to stop polling and disable the handler. */
ucb->stopped = true;
mb();
wake_up(&ucb->ts_wait);
disable_irq(ucb->irq);
ucb1400_ts_irq_disable(ucb);
ucb1400_reg_write(ucb->ac97, UCB_TS_CR, 0);
}
/* Must be called with ts->lock held */
static void ucb1400_ts_start(struct ucb1400_ts *ucb)
{
/* Tell IRQ thread that it may poll the device. */
ucb->stopped = false;
mb();
ucb1400_ts_mode_int(ucb);
ucb1400_ts_irq_enable(ucb);
enable_irq(ucb->irq);
}
static int ucb1400_ts_open(struct input_dev *idev)
{
struct ucb1400_ts *ucb = input_get_drvdata(idev);
ucb1400_ts_start(ucb);
return 0;
}
static void ucb1400_ts_close(struct input_dev *idev)
{
struct ucb1400_ts *ucb = input_get_drvdata(idev);
ucb1400_ts_stop(ucb);
}
#ifndef NO_IRQ
#define NO_IRQ 0
#endif
/*
* Try to probe our interrupt, rather than relying on lots of
* hard-coded machine dependencies.
*/
static int ucb1400_ts_detect_irq(struct ucb1400_ts *ucb,
struct platform_device *pdev)
{
unsigned long mask, timeout;
mask = probe_irq_on();
/* Enable the ADC interrupt. */
ucb1400_reg_write(ucb->ac97, UCB_IE_RIS, UCB_IE_ADC);
ucb1400_reg_write(ucb->ac97, UCB_IE_FAL, UCB_IE_ADC);
ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0xffff);
ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0);
/* Cause an ADC interrupt. */
ucb1400_reg_write(ucb->ac97, UCB_ADC_CR, UCB_ADC_ENA);
ucb1400_reg_write(ucb->ac97, UCB_ADC_CR, UCB_ADC_ENA | UCB_ADC_START);
/* Wait for the conversion to complete. */
timeout = jiffies + HZ/2;
while (!(ucb1400_reg_read(ucb->ac97, UCB_ADC_DATA) &
UCB_ADC_DAT_VALID)) {
cpu_relax();
if (time_after(jiffies, timeout)) {
dev_err(&pdev->dev, "timed out in IRQ probe\n");
probe_irq_off(mask);
return -ENODEV;
}
}
ucb1400_reg_write(ucb->ac97, UCB_ADC_CR, 0);
/* Disable and clear interrupt. */
ucb1400_reg_write(ucb->ac97, UCB_IE_RIS, 0);
ucb1400_reg_write(ucb->ac97, UCB_IE_FAL, 0);
ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0xffff);
ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0);
/* Read triggered interrupt. */
ucb->irq = probe_irq_off(mask);
if (ucb->irq < 0 || ucb->irq == NO_IRQ)
return -ENODEV;
return 0;
}
static int ucb1400_ts_probe(struct platform_device *pdev)
{
struct ucb1400_ts *ucb = dev_get_platdata(&pdev->dev);
int error, x_res, y_res;
u16 fcsr;
ucb->ts_idev = input_allocate_device();
if (!ucb->ts_idev) {
error = -ENOMEM;
goto err;
}
/* Only in case the IRQ line wasn't supplied, try detecting it */
if (ucb->irq < 0) {
error = ucb1400_ts_detect_irq(ucb, pdev);
if (error) {
dev_err(&pdev->dev, "IRQ probe failed\n");
goto err_free_devs;
}
}
dev_dbg(&pdev->dev, "found IRQ %d\n", ucb->irq);
init_waitqueue_head(&ucb->ts_wait);
input_set_drvdata(ucb->ts_idev, ucb);
ucb->ts_idev->dev.parent = &pdev->dev;
ucb->ts_idev->name = "UCB1400 touchscreen interface";
ucb->ts_idev->id.vendor = ucb1400_reg_read(ucb->ac97,
AC97_VENDOR_ID1);
ucb->ts_idev->id.product = ucb->id;
ucb->ts_idev->open = ucb1400_ts_open;
ucb->ts_idev->close = ucb1400_ts_close;
ucb->ts_idev->evbit[0] = BIT_MASK(EV_ABS) | BIT_MASK(EV_KEY);
ucb->ts_idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
/*
* Enable ADC filter to prevent horrible jitter on Colibri.
* This also further reduces jitter on boards where ADCSYNC
* pin is connected.
*/
fcsr = ucb1400_reg_read(ucb->ac97, UCB_FCSR);
ucb1400_reg_write(ucb->ac97, UCB_FCSR, fcsr | UCB_FCSR_AVE);
ucb1400_adc_enable(ucb->ac97);
x_res = ucb1400_ts_read_xres(ucb);
y_res = ucb1400_ts_read_yres(ucb);
ucb1400_adc_disable(ucb->ac97);
dev_dbg(&pdev->dev, "x/y = %d/%d\n", x_res, y_res);
input_set_abs_params(ucb->ts_idev, ABS_X, 0, x_res, 0, 0);
input_set_abs_params(ucb->ts_idev, ABS_Y, 0, y_res, 0, 0);
input_set_abs_params(ucb->ts_idev, ABS_PRESSURE, 0, 0, 0, 0);
ucb1400_ts_stop(ucb);
error = request_threaded_irq(ucb->irq, NULL, ucb1400_irq,
IRQF_TRIGGER_RISING | IRQF_ONESHOT,
"UCB1400", ucb);
if (error) {
dev_err(&pdev->dev,
"unable to grab irq%d: %d\n", ucb->irq, error);
goto err_free_devs;
}
error = input_register_device(ucb->ts_idev);
if (error)
goto err_free_irq;
return 0;
err_free_irq:
free_irq(ucb->irq, ucb);
err_free_devs:
input_free_device(ucb->ts_idev);
err:
return error;
}
static int ucb1400_ts_remove(struct platform_device *pdev)
{
struct ucb1400_ts *ucb = dev_get_platdata(&pdev->dev);
free_irq(ucb->irq, ucb);
input_unregister_device(ucb->ts_idev);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int ucb1400_ts_suspend(struct device *dev)
{
struct ucb1400_ts *ucb = dev_get_platdata(dev);
struct input_dev *idev = ucb->ts_idev;
mutex_lock(&idev->mutex);
if (idev->users)
ucb1400_ts_start(ucb);
mutex_unlock(&idev->mutex);
return 0;
}
static int ucb1400_ts_resume(struct device *dev)
{
struct ucb1400_ts *ucb = dev_get_platdata(dev);
struct input_dev *idev = ucb->ts_idev;
mutex_lock(&idev->mutex);
if (idev->users)
ucb1400_ts_stop(ucb);
mutex_unlock(&idev->mutex);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(ucb1400_ts_pm_ops,
ucb1400_ts_suspend, ucb1400_ts_resume);
static struct platform_driver ucb1400_ts_driver = {
.probe = ucb1400_ts_probe,
.remove = ucb1400_ts_remove,
.driver = {
.name = "ucb1400_ts",
.owner = THIS_MODULE,
.pm = &ucb1400_ts_pm_ops,
},
};
module_platform_driver(ucb1400_ts_driver);
module_param(adcsync, bool, 0444);
MODULE_PARM_DESC(adcsync, "Synchronize touch readings with ADCSYNC pin.");
module_param(ts_delay, int, 0444);
MODULE_PARM_DESC(ts_delay, "Delay between panel setup and"
" position read. Default = 55us.");
module_param(ts_delay_pressure, int, 0444);
MODULE_PARM_DESC(ts_delay_pressure,
"delay between panel setup and pressure read."
" Default = 0us.");
MODULE_DESCRIPTION("Philips UCB1400 touchscreen driver");
MODULE_LICENSE("GPL");