linux/drivers/input/misc/wm831x-on.c

151 lines
3.8 KiB
C

/**
* wm831x-on.c - WM831X ON pin driver
*
* Copyright (C) 2009 Wolfson Microelectronics plc
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file "COPYING" in the main directory of this
* archive for more details.
*
* 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
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/workqueue.h>
#include <linux/mfd/wm831x/core.h>
struct wm831x_on {
struct input_dev *dev;
struct delayed_work work;
struct wm831x *wm831x;
};
/*
* The chip gives us an interrupt when the ON pin is asserted but we
* then need to poll to see when the pin is deasserted.
*/
static void wm831x_poll_on(struct work_struct *work)
{
struct wm831x_on *wm831x_on = container_of(work, struct wm831x_on,
work.work);
struct wm831x *wm831x = wm831x_on->wm831x;
int poll, ret;
ret = wm831x_reg_read(wm831x, WM831X_ON_PIN_CONTROL);
if (ret >= 0) {
poll = !(ret & WM831X_ON_PIN_STS);
input_report_key(wm831x_on->dev, KEY_POWER, poll);
input_sync(wm831x_on->dev);
} else {
dev_err(wm831x->dev, "Failed to read ON status: %d\n", ret);
poll = 1;
}
if (poll)
schedule_delayed_work(&wm831x_on->work, 100);
}
static irqreturn_t wm831x_on_irq(int irq, void *data)
{
struct wm831x_on *wm831x_on = data;
schedule_delayed_work(&wm831x_on->work, 0);
return IRQ_HANDLED;
}
static int wm831x_on_probe(struct platform_device *pdev)
{
struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
struct wm831x_on *wm831x_on;
int irq = wm831x_irq(wm831x, platform_get_irq(pdev, 0));
int ret;
wm831x_on = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_on),
GFP_KERNEL);
if (!wm831x_on) {
dev_err(&pdev->dev, "Can't allocate data\n");
return -ENOMEM;
}
wm831x_on->wm831x = wm831x;
INIT_DELAYED_WORK(&wm831x_on->work, wm831x_poll_on);
wm831x_on->dev = devm_input_allocate_device(&pdev->dev);
if (!wm831x_on->dev) {
dev_err(&pdev->dev, "Can't allocate input dev\n");
ret = -ENOMEM;
goto err;
}
wm831x_on->dev->evbit[0] = BIT_MASK(EV_KEY);
wm831x_on->dev->keybit[BIT_WORD(KEY_POWER)] = BIT_MASK(KEY_POWER);
wm831x_on->dev->name = "wm831x_on";
wm831x_on->dev->phys = "wm831x_on/input0";
wm831x_on->dev->dev.parent = &pdev->dev;
ret = request_threaded_irq(irq, NULL, wm831x_on_irq,
IRQF_TRIGGER_RISING | IRQF_ONESHOT,
"wm831x_on",
wm831x_on);
if (ret < 0) {
dev_err(&pdev->dev, "Unable to request IRQ: %d\n", ret);
goto err_input_dev;
}
ret = input_register_device(wm831x_on->dev);
if (ret) {
dev_dbg(&pdev->dev, "Can't register input device: %d\n", ret);
goto err_irq;
}
platform_set_drvdata(pdev, wm831x_on);
return 0;
err_irq:
free_irq(irq, wm831x_on);
err_input_dev:
err:
return ret;
}
static int wm831x_on_remove(struct platform_device *pdev)
{
struct wm831x_on *wm831x_on = platform_get_drvdata(pdev);
int irq = platform_get_irq(pdev, 0);
free_irq(irq, wm831x_on);
cancel_delayed_work_sync(&wm831x_on->work);
return 0;
}
static struct platform_driver wm831x_on_driver = {
.probe = wm831x_on_probe,
.remove = wm831x_on_remove,
.driver = {
.name = "wm831x-on",
},
};
module_platform_driver(wm831x_on_driver);
MODULE_ALIAS("platform:wm831x-on");
MODULE_DESCRIPTION("WM831x ON pin");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");