linux-kernel-test/drivers/input/misc/wm831x-on.c
Mark Brown cd99758ba3 mfd: Convert wm831x to irq_domain
The modern idiom is to use irq_domain to allocate interrupts. This is
useful partly to allow further infrastructure to be based on the domains
and partly because it makes it much easier to allocate virtual interrupts
to devices as we don't need to allocate a contiguous range of interrupt
numbers.

Convert the wm831x driver over to this infrastructure, using a legacy
IRQ mapping if an irq_base is specified in platform data and otherwise
using a linear mapping, always registering the interrupts even if they
won't ever be used. Only boards which need to use the GPIOs as
interrupts should need to use an irq_base.

This means that we can't use the MFD irq_base management since the
unless we're using an explicit irq_base from platform data we can't rely
on a linear mapping of interrupts.  Instead we need to map things via
the irq_domain - provide a conveniencem function wm831x_irq() to save a
small amount of typing when doing so. Looking at this I couldn't clearly
see anything the MFD core could do to make this nicer.

Since we're not supporting device tree yet there's no meaningful
advantage if we don't do this conversion in one, the fact that the
interrupt resources are used for repeated IP blocks makes accessor
functions for the irq_domain more trouble to do than they're worth.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2012-05-20 17:27:07 +02:00

155 lines
4.0 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/init.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 __devinit 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 = kzalloc(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 = input_allocate_device();
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, "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:
input_free_device(wm831x_on->dev);
err:
kfree(wm831x_on);
return ret;
}
static int __devexit 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);
input_unregister_device(wm831x_on->dev);
kfree(wm831x_on);
return 0;
}
static struct platform_driver wm831x_on_driver = {
.probe = wm831x_on_probe,
.remove = __devexit_p(wm831x_on_remove),
.driver = {
.name = "wm831x-on",
.owner = THIS_MODULE,
},
};
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>");