drivers/input/misc/max8925_onkey.c

   1 /**
   2  * max8925_onkey.c - MAX8925 ONKEY driver
   3  *
   4  * Copyright (C) 2009 Marvell International Ltd.
   5  *      Haojian Zhuang <haojian.zhuang@marvell.com>
   6  *
   7  * This file is subject to the terms and conditions of the GNU General
   8  * Public License. See the file "COPYING" in the main directory of this
   9  * archive for more details.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include <linux/kernel.h>
  22 #include <linux/module.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/i2c.h>
  25 #include <linux/input.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/mfd/max8925.h>
  28 #include <linux/slab.h>
  29
  30 #define HARDRESET_EN            (1 << 7)
  31 #define PWREN_EN                (1 << 7)
  32
  33 struct max8925_onkey_info {
  34         struct input_dev        *idev;
  35         struct i2c_client       *i2c;
  36         int                     irq;
  37 };
  38
  39 /*
  40  * MAX8925 gives us an interrupt when ONKEY is held for 3 seconds.
  41  * max8925_set_bits() operates I2C bus and may sleep. So implement
  42  * it in thread IRQ handler.
  43  */
  44 static irqreturn_t max8925_onkey_handler(int irq, void *data)
  45 {
  46         struct max8925_onkey_info *info = data;
  47
  48         input_report_key(info->idev, KEY_POWER, 1);
  49         input_sync(info->idev);
  50
  51         /* Enable hardreset to halt if system isn't shutdown on time */
  52         max8925_set_bits(info->i2c, MAX8925_SYSENSEL,
  53                          HARDRESET_EN, HARDRESET_EN);
  54
  55         return IRQ_HANDLED;
  56 }
  57
  58 static int __devinit max8925_onkey_probe(struct platform_device *pdev)
  59 {
  60         struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
  61         struct max8925_onkey_info *info;
  62         int error;
  63
  64         info = kzalloc(sizeof(struct max8925_onkey_info), GFP_KERNEL);
  65         if (!info)
  66                 return -ENOMEM;
  67
  68         info->i2c = chip->i2c;
  69         info->irq = chip->irq_base + MAX8925_IRQ_GPM_SW_3SEC;
  70
  71         info->idev = input_allocate_device();
  72         if (!info->idev) {
  73                 dev_err(chip->dev, "Failed to allocate input dev\n");
  74                 error = -ENOMEM;
  75                 goto out_input;
  76         }
  77
  78         info->idev->name = "max8925_on";
  79         info->idev->phys = "max8925_on/input0";
  80         info->idev->id.bustype = BUS_I2C;
  81         info->idev->dev.parent = &pdev->dev;
  82         info->idev->evbit[0] = BIT_MASK(EV_KEY);
  83         info->idev->keybit[BIT_WORD(KEY_POWER)] = BIT_MASK(KEY_POWER);
  84
  85         error = request_threaded_irq(info->irq, NULL, max8925_onkey_handler,
  86                                      IRQF_ONESHOT, "onkey", info);
  87         if (error < 0) {
  88                 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
  89                         info->irq, error);
  90                 goto out_irq;
  91         }
  92
  93         error = input_register_device(info->idev);
  94         if (error) {
  95                 dev_err(chip->dev, "Can't register input device: %d\n", error);
  96                 goto out;
  97         }
  98
  99         platform_set_drvdata(pdev, info);
 100
 101         return 0;
 102
 103 out:
 104         free_irq(info->irq, info);
 105 out_irq:
 106         input_free_device(info->idev);
 107 out_input:
 108         kfree(info);
 109         return error;
 110 }
 111
 112 static int __devexit max8925_onkey_remove(struct platform_device *pdev)
 113 {
 114         struct max8925_onkey_info *info = platform_get_drvdata(pdev);
 115
 116         free_irq(info->irq, info);
 117         input_unregister_device(info->idev);
 118         kfree(info);
 119
 120         platform_set_drvdata(pdev, NULL);
 121
 122         return 0;
 123 }
 124
 125 static struct platform_driver max8925_onkey_driver = {
 126         .driver         = {
 127                 .name   = "max8925-onkey",
 128                 .owner  = THIS_MODULE,
 129         },
 130         .probe          = max8925_onkey_probe,
 131         .remove         = __devexit_p(max8925_onkey_remove),
 132 };
 133
 134 static int __init max8925_onkey_init(void)
 135 {
 136         return platform_driver_register(&max8925_onkey_driver);
 137 }
 138 module_init(max8925_onkey_init);
 139
 140 static void __exit max8925_onkey_exit(void)
 141 {
 142         platform_driver_unregister(&max8925_onkey_driver);
 143 }
 144 module_exit(max8925_onkey_exit);
 145
 146 MODULE_DESCRIPTION("Maxim MAX8925 ONKEY driver");
 147 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
 148 MODULE_LICENSE("GPL");