drivers/input/misc/twl4030-pwrbutton.c

   1 /**
   2  * twl4030-pwrbutton.c - TWL4030 Power Button Input Driver
   3  *
   4  * Copyright (C) 2008-2009 Nokia Corporation
   5  *
   6  * Written by Peter De Schrijver <peter.de-schrijver@nokia.com>
   7  * Several fixes by Felipe Balbi <felipe.balbi@nokia.com>
   8  *
   9  * This file is subject to the terms and conditions of the GNU General
  10  * Public License. See the file "COPYING" in the main directory of this
  11  * archive for more details.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25 #include <linux/kernel.h>
  26 #include <linux/errno.h>
  27 #include <linux/input.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/platform_device.h>
  30 #include <linux/i2c/twl.h>
  31
  32 #define PWR_PWRON_IRQ (1 << 0)
  33
  34 #define STS_HW_CONDITIONS 0xf
  35
  36 static irqreturn_t powerbutton_irq(int irq, void *_pwr)
  37 {
  38         struct input_dev *pwr = _pwr;
  39         int err;
  40         u8 value;
  41
  42         err = twl_i2c_read_u8(TWL4030_MODULE_PM_MASTER, &value,
  43                                 STS_HW_CONDITIONS);
  44         if (!err)  {
  45                 input_report_key(pwr, KEY_POWER, value & PWR_PWRON_IRQ);
  46                 input_sync(pwr);
  47         } else {
  48                 dev_err(pwr->dev.parent, "twl4030: i2c error %d while reading"
  49                         " TWL4030 PM_MASTER STS_HW_CONDITIONS register\n", err);
  50         }
  51
  52         return IRQ_HANDLED;
  53 }
  54
  55 static int __init twl4030_pwrbutton_probe(struct platform_device *pdev)
  56 {
  57         struct input_dev *pwr;
  58         int irq = platform_get_irq(pdev, 0);
  59         int err;
  60
  61         pwr = input_allocate_device();
  62         if (!pwr) {
  63                 dev_dbg(&pdev->dev, "Can't allocate power button\n");
  64                 return -ENOMEM;
  65         }
  66
  67         pwr->evbit[0] = BIT_MASK(EV_KEY);
  68         pwr->keybit[BIT_WORD(KEY_POWER)] = BIT_MASK(KEY_POWER);
  69         pwr->name = "twl4030_pwrbutton";
  70         pwr->phys = "twl4030_pwrbutton/input0";
  71         pwr->dev.parent = &pdev->dev;
  72
  73         err = request_threaded_irq(irq, NULL, powerbutton_irq,
  74                         IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
  75                         "twl4030_pwrbutton", pwr);
  76         if (err < 0) {
  77                 dev_dbg(&pdev->dev, "Can't get IRQ for pwrbutton: %d\n", err);
  78                 goto free_input_dev;
  79         }
  80
  81         err = input_register_device(pwr);
  82         if (err) {
  83                 dev_dbg(&pdev->dev, "Can't register power button: %d\n", err);
  84                 goto free_irq;
  85         }
  86
  87         platform_set_drvdata(pdev, pwr);
  88
  89         return 0;
  90
  91 free_irq:
  92         free_irq(irq, pwr);
  93 free_input_dev:
  94         input_free_device(pwr);
  95         return err;
  96 }
  97
  98 static int __exit twl4030_pwrbutton_remove(struct platform_device *pdev)
  99 {
 100         struct input_dev *pwr = platform_get_drvdata(pdev);
 101         int irq = platform_get_irq(pdev, 0);
 102
 103         free_irq(irq, pwr);
 104         input_unregister_device(pwr);
 105
 106         return 0;
 107 }
 108
 109 static struct platform_driver twl4030_pwrbutton_driver = {
 110         .remove         = __exit_p(twl4030_pwrbutton_remove),
 111         .driver         = {
 112                 .name   = "twl4030_pwrbutton",
 113                 .owner  = THIS_MODULE,
 114         },
 115 };
 116
 117 static int __init twl4030_pwrbutton_init(void)
 118 {
 119         return platform_driver_probe(&twl4030_pwrbutton_driver,
 120                         twl4030_pwrbutton_probe);
 121 }
 122 module_init(twl4030_pwrbutton_init);
 123
 124 static void __exit twl4030_pwrbutton_exit(void)
 125 {
 126         platform_driver_unregister(&twl4030_pwrbutton_driver);
 127 }
 128 module_exit(twl4030_pwrbutton_exit);
 129
 130 MODULE_ALIAS("platform:twl4030_pwrbutton");
 131 MODULE_DESCRIPTION("Triton2 Power Button");
 132 MODULE_LICENSE("GPL");
 133 MODULE_AUTHOR("Peter De Schrijver <peter.de-schrijver@nokia.com>");
 134 MODULE_AUTHOR("Felipe Balbi <felipe.balbi@nokia.com>");
 135