diff options
Diffstat (limited to 'kernel/drivers/input/misc/wm831x-on.c')
| -rw-r--r-- | kernel/drivers/input/misc/wm831x-on.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/kernel/drivers/input/misc/wm831x-on.c b/kernel/drivers/input/misc/wm831x-on.c new file mode 100644 index 000000000..59d4f7bcb --- /dev/null +++ b/kernel/drivers/input/misc/wm831x-on.c @@ -0,0 +1,149 @@ +/** + * 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, "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>"); + |