/*
* Samsung S3C24XX touchscreen driver
*
* This program is free software; you can redistribute it and/or modify
* it under the term 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 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 program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Copyright 2004 Arnaud Patard <arnaud.patard@rtp-net.org>
* Copyright 2008 Ben Dooks <ben-linux@fluff.org>
* Copyright 2009 Simtec Electronics <linux@simtec.co.uk>
*
* Additional work by Herbert Pötzl <herbert@13thfloor.at> and
* Harald Welte <laforge@openmoko.org>
*/
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/gpio.h>
#include <linux/input.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <plat/adc.h>
#include <plat/regs-adc.h>
#include <mach/regs-gpio.h>
#include <mach/ts.h>
#define TSC_SLEEP (S3C2410_ADCTSC_PULL_UP_DISABLE | S3C2410_ADCTSC_XY_PST(0))
#define INT_DOWN (0)
#define INT_UP (1 << 8)
#define WAIT4INT (S3C2410_ADCTSC_YM_SEN | \
S3C2410_ADCTSC_YP_SEN | \
S3C2410_ADCTSC_XP_SEN | \
S3C2410_ADCTSC_XY_PST(3))
#define AUTOPST (S3C2410_ADCTSC_YM_SEN | \
S3C2410_ADCTSC_YP_SEN | \
S3C2410_ADCTSC_XP_SEN | \
S3C2410_ADCTSC_AUTO_PST | \
S3C2410_ADCTSC_XY_PST(0))
/* Per-touchscreen data. */
/**
* struct s3c2410ts - driver touchscreen state.
* @client: The ADC client we registered with the core driver.
* @dev: The device we are bound to.
* @input: The input device we registered with the input subsystem.
* @clock: The clock for the adc.
* @io: Pointer to the IO base.
* @xp: The accumulated X position data.
* @yp: The accumulated Y position data.
* @irq_tc: The interrupt number for pen up/down interrupt
* @count: The number of samples collected.
* @shift: The log2 of the maximum count to read in one go.
*/
struct s3c2410ts {
struct s3c_adc_client *client;
struct device *dev;
struct input_dev *input;
struct clk *clock;
void __iomem *io;
unsigned long xp;
unsigned long yp;
int irq_tc;
int count;
int shift;
};
static struct s3c2410ts ts;
/**
* s3c2410_ts_connect - configure gpio for s3c2410 systems
*
* Configure the GPIO for the S3C2410 system, where we have external FETs
* connected to the device (later systems such as the S3C2440 integrate
* these into the device).
*/
static inline void s3c2410_ts_connect(void)
{
s3c2410_gpio_cfgpin(S3C2410_GPG(12), S3C2410_GPG12_XMON);
s3c2410_gpio_cfgpin(S3C2410_GPG(13), S3C2410_GPG13_nXPON);
s3c2410_gpio_cfgpin(S3C2410_GPG(14), S3C2410_GPG14_YMON);
s3c2410_gpio_cfgpin(S3C2410_GPG(15), S3C2410_GPG15_nYPON);
}
/**
* get_down - return the down state of the pen
* @data0: The data read from ADCDAT0 register.
* @data1: The data read from ADCDAT1 register.
*
* Return non-zero if both readings show that the pen is down.
*/
static inline bool get_down(unsigned long data0, unsigned long data1)
{
/* returns true if both data values show stylus down */
return (!(data0 & S3C2410_ADCDAT0_UPDOWN) &&
!(data1 & S3C2410_ADCDAT0_UPDOWN));
}
static void touch_timer_fire(unsigned long data)
{
unsigned long data0;
unsigned long data1;
bool down;
data0 = readl(ts.io + S3C2410_ADCDAT0);
data1 = readl(ts.io + S3C2410_ADCDAT1);
down = get_down(data0, data1);
if (down) {
if (ts.count == (1 << ts.shift)) {
ts.xp >>= ts.shift;
ts.yp >>= ts.shift;
dev_dbg(ts.dev, "%s: X=%lu, Y=%lu, count=%d\n",
__func__, ts.xp, ts.yp, ts.count);
input_report_abs(ts.input, ABS_X, ts.xp);
input_report_abs(ts.input, ABS_Y, ts.yp);
input_report_key(ts.input, BTN_TOUCH, 1);
input_sync(ts.input);
ts.xp = 0;
ts.yp = 0;
ts.count = 0;
}
s3c_adc_start(ts.client, 0, 1 << ts.shift);
} else {
ts.xp = 0;
ts.yp = 0;
ts.count = 0;
input_report_key(ts.input, BTN_TOUCH, 0);
input_sync(ts.input);
writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC);
}
}
static DEFINE_TIMER(touch_timer, touch_timer_fire, 0, 0);
/**
* stylus_irq - touchscreen stylus event interrupt
* @irq: The interrupt number
* @dev_id: The device ID.
*
* Called when the IRQ_TC is fired for a pen up or down event.
*/
static irqreturn_t stylus_irq(int irq, void *dev_id)
{
unsigned long data0;
unsigned long data1;
bool down;
data0 = readl(ts.io + S3C2410_ADCDAT0);
data1 = readl(ts.io + S3C2410_ADCDAT1);
down = get_down(data0, data1);
/* TODO we should never get an interrupt with down set while
* the timer is running, but maybe we ought to verify that the
* timer isn't running anyways. */
if (down)
s3c_adc_start(ts.client, 0, 1 << ts.shift);
else
dev_info(ts.dev, "%s: count=%d\n", __func__, ts.count);
return IRQ_HANDLED;
}
/**
* s3c24xx_ts_conversion - ADC conversion callback
* @client: The client that was registered with the ADC core.
* @data0: The reading from ADCDAT0.
* @data1: The reading from ADCDAT1.
* @left: The number of samples left.
*
* Called when a conversion has finished.
*/
static void s3c24xx_ts_conversion(struct s3c_adc_client *client,
unsigned data0, unsigned data1,
unsigned *left)
{
dev_dbg(ts.dev, "%s: %d,%d\n", __func__, data0, data1);
ts.xp += data0;
ts.yp += data1;
ts.count++;
/* From tests, it seems that it is unlikely to get a pen-up
* event during the conversion process which means we can
* ignore any pen-up events with less than the requisite
* count done.
*
* In several thousand conversions, no pen-ups where detected
* before count completed.
*/
}
/**
* s3c24xx_ts_select - ADC selection callback.
* @client: The client that was registered with the ADC core.
* @select: The reason for select.
*
* Called when the ADC core selects (or deslects) us as a client.
*/
static void s3c24xx_ts_select(struct s3c_adc_client *client, unsigned select)
{
if (select) {
writel(S3C2410_ADCTSC_PULL_UP_DISABLE | AUTOPST,
ts.io + S3C2410_ADCTSC);
} else {
mod_timer(&touch_timer, jiffies+1);
writel(WAIT4INT | INT_UP, ts.io + S3C2410_ADCTSC);
}
}
/**
* s3c2410ts_probe - device core probe entry point
* @pdev: The device we are being bound to.
*
* Initialise, find and allocate any resources we need to run and then
* register with the ADC and input systems.
*/
static int __devinit s3c2410ts_probe(struct platform_device *pdev)
{
struct s3c2410_ts_mach_info *info;
struct device *dev = &pdev->dev;
struct input_dev *input_dev;
struct resource *res;
int ret = -EINVAL;
/* Initialise input stuff */
memset(&ts, 0, sizeof(struct s3c2410ts));
ts.dev = dev;
info = pdev->dev.platform_data;
if (!info) {
dev_err(dev, "no platform data, cannot attach\n");
return -EINVAL;
}
dev_dbg(dev, "initialising touchscreen\n");
ts.clock = clk_get(dev, "adc");
if (IS_ERR(ts.clock)) {
dev_err(dev, "cannot get adc clock source\n");
return -ENOENT;
}
clk_enable(ts.clock);
dev_dbg(dev, "got and enabled clocks\n");
ts.irq_tc = ret = platform_get_irq(pdev, 0);
if (ret < 0) {
dev_err(dev, "no resource for interrupt\n");
goto err_clk;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(dev, "no resource for registers\n");
ret = -ENOENT;
goto err_clk;
}
ts.io = ioremap(res->start, resource_size(res));
if (ts.io == NULL) {
dev_err(dev, "cannot map registers\n");
ret = -ENOMEM;
goto err_clk;
}
/* Configure the touchscreen external FETs on the S3C2410 */
if (!platform_get_device_id(pdev)->driver_data)
s3c2410_ts_connect();
ts.client = s3c_adc_register(pdev, s3c24xx_ts_select,
s3c24xx_ts_conversion, 1);
if (IS_ERR(ts.client)) {
dev_err(dev, "failed to register adc client\n");
ret = PTR_ERR(ts.client);
goto err_iomap;
}
/* Initialise registers */
if ((info->delay & 0xffff) > 0)
writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY);
writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC);
input_dev = input_allocate_device();
if (!input_dev) {
dev_err(dev, "Unable to allocate the input device !!\n");
ret = -ENOMEM;
goto err_iomap;
}
ts.input = input_dev;
ts.input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
ts.input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
input_set_abs_params(ts.input, ABS_X, 0, 0x3FF, 0, 0);
input_set_abs_params(ts.input, ABS_Y, 0, 0x3FF, 0, 0);
ts.input->name = "S3C24XX TouchScreen";
ts.input->id.bustype = BUS_HOST;
ts.input->id.vendor = 0xDEAD;
ts.input->id.product = 0xBEEF;
ts.input->id.version = 0x0102;
ts.shift = info->oversampling_shift;
ret = request_irq(ts.irq_tc, stylus_irq, IRQF_DISABLED,
"s3c2410_ts_pen", ts.input);
if (ret) {
dev_err(dev, "cannot get TC interrupt\n");
goto err_inputdev;
}
dev_info(dev, "driver attached, registering input device\n");
/* All went ok, so register to the input system */
ret = input_register_device(ts.input);
if (ret < 0) {
dev_err(dev, "failed to register input device\n");
ret = -EIO;
goto err_tcirq;
}
return 0;
err_tcirq:
free_irq(ts.irq_tc, ts.input);
err_inputdev:
input_unregister_device(ts.input);
err_iomap:
iounmap(ts.io);
err_clk:
del_timer_sync(&touch_timer);
clk_put(ts.clock);
return ret;
}
/**
* s3c2410ts_remove - device core removal entry point
* @pdev: The device we are being removed from.
*
* Free up our state ready to be removed.
*/
static int __devexit s3c2410ts_remove(struct platform_device *pdev)
{
free_irq(ts.irq_tc, ts.input);
del_timer_sync(&touch_timer);
clk_disable(ts.clock);
clk_put(ts.clock);
input_unregister_device(ts.input);
iounmap(ts.io);
return 0;
}
#ifdef CONFIG_PM
static int s3c2410ts_suspend(struct device *dev)
{
writel(TSC_SLEEP, ts.io + S3C2410_ADCTSC);
disable_irq(ts.irq_tc);
clk_disable(ts.clock);
return 0;
}
static int s3c2410ts_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct s3c2410_ts_mach_info *info = pdev->dev.platform_data;
clk_enable(ts.clock);
enable_irq(ts.irq_tc);
/* Initialise registers */
if ((info->delay & 0xffff) > 0)
writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY);
writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC);
return 0;
}
static struct dev_pm_ops s3c_ts_pmops = {
.suspend = s3c2410ts_suspend,
.resume = s3c2410ts_resume,
};
#endif
static struct platform_device_id s3cts_driver_ids[] = {
{ "s3c2410-ts", 0 },
{ "s3c2440-ts", 1 },
{ }
};
MODULE_DEVICE_TABLE(platform, s3cts_driver_ids);
static struct platform_driver s3c_ts_driver = {
.driver = {
.name = "s3c24xx-ts",
.owner = THIS_MODULE,
#ifdef CONFIG_PM
.pm = &s3c_ts_pmops,
#endif
},
.id_table = s3cts_driver_ids,
.probe = s3c2410ts_probe,
.remove = __devexit_p(s3c2410ts_remove),
};
static int __init s3c2410ts_init(void)
{
return platform_driver_register(&s3c_ts_driver);
}
static void __exit s3c2410ts_exit(void)
{
platform_driver_unregister(&s3c_ts_driver);
}
module_init(s3c2410ts_init);
module_exit(s3c2410ts_exit);
MODULE_AUTHOR("Arnaud Patard <arnaud.patard@rtp-net.org>, "
"Ben Dooks <ben@simtec.co.uk>, "
"Simtec Electronics <linux@simtec.co.uk>");
MODULE_DESCRIPTION("S3C24XX Touchscreen driver");
MODULE_LICENSE("GPL v2");
