/** * 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 = 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>");