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 SW_INPUT                (1 << 7)        /* 0/1 -- up/down */
  31 #define HARDRESET_EN            (1 << 7)
  32 #define PWREN_EN                (1 << 7)
  33
  34 struct max8925_onkey_info {
  35         struct input_dev        *idev;
  36         struct i2c_client       *i2c;
  37         struct device           *dev;
  38         int                     irq[2];
  39 };
  40
  41 /*
  42  * MAX8925 gives us an interrupt when ONKEY is pressed or released.
  43  * max8925_set_bits() operates I2C bus and may sleep. So implement
  44  * it in thread IRQ handler.
  45  */
  46 static irqreturn_t max8925_onkey_handler(int irq, void *data)
  47 {
  48         struct max8925_onkey_info *info = data;
  49         int ret, event;
  50
  51         ret = max8925_reg_read(info->i2c, MAX8925_ON_OFF_STATUS);
  52         if (ret & SW_INPUT)
  53                 event = 1;
  54         else
  55                 event = 0;
  56         input_report_key(info->idev, KEY_POWER, event);
  57         input_sync(info->idev);
  58
  59         dev_dbg(info->dev, "onkey event:%d\n", event);
  60
  61         /* Enable hardreset to halt if system isn't shutdown on time */
  62         max8925_set_bits(info->i2c, MAX8925_SYSENSEL,
  63                          HARDRESET_EN, HARDRESET_EN);
  64
  65         return IRQ_HANDLED;
  66 }
  67
  68 static int __devinit max8925_onkey_probe(struct platform_device *pdev)
  69 {
  70         struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
  71         struct max8925_onkey_info *info;
  72         int irq[2], error;
  73
  74         irq[0] = platform_get_irq(pdev, 0);
  75         if (irq[0] < 0) {
  76                 dev_err(&pdev->dev, "No IRQ resource!\n");
  77                 return -EINVAL;
  78         }
  79         irq[1] = platform_get_irq(pdev, 1);
  80         if (irq[1] < 0) {
  81                 dev_err(&pdev->dev, "No IRQ resource!\n");
  82                 return -EINVAL;
  83         }
  84
  85         info = kzalloc(sizeof(struct max8925_onkey_info), GFP_KERNEL);
  86         if (!info)
  87                 return -ENOMEM;
  88
  89         info->i2c = chip->i2c;
  90         info->dev = &pdev->dev;
  91         irq[0] += chip->irq_base;
  92         irq[1] += chip->irq_base;
  93
  94         error = request_threaded_irq(irq[0], NULL, max8925_onkey_handler,
  95                                      IRQF_ONESHOT, "onkey-down", info);
  96         if (error < 0) {
  97                 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
  98                         irq[0], error);
  99                 goto out;
 100         }
 101         error = request_threaded_irq(irq[1], NULL, max8925_onkey_handler,
 102                                      IRQF_ONESHOT, "onkey-up", info);
 103         if (error < 0) {
 104                 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
 105                         irq[1], error);
 106                 goto out_irq;
 107         }
 108
 109         info->idev = input_allocate_device();
 110         if (!info->idev) {
 111                 dev_err(chip->dev, "Failed to allocate input dev\n");
 112                 error = -ENOMEM;
 113                 goto out_input;
 114         }
 115
 116         info->idev->name = "max8925_on";
 117         info->idev->phys = "max8925_on/input0";
 118         info->idev->id.bustype = BUS_I2C;
 119         info->idev->dev.parent = &pdev->dev;
 120         info->irq[0] = irq[0];
 121         info->irq[1] = irq[1];
 122         info->idev->evbit[0] = BIT_MASK(EV_KEY);
 123         info->idev->keybit[BIT_WORD(KEY_POWER)] = BIT_MASK(KEY_POWER);
 124
 125
 126         error = input_register_device(info->idev);
 127         if (error) {
 128                 dev_err(chip->dev, "Can't register input device: %d\n", error);
 129                 goto out_reg;
 130         }
 131
 132         platform_set_drvdata(pdev, info);
 133
 134         return 0;
 135
 136 out_reg:
 137         input_free_device(info->idev);
 138 out_input:
 139         free_irq(info->irq[1], info);
 140 out_irq:
 141         free_irq(info->irq[0], info);
 142 out:
 143         kfree(info);
 144         return error;
 145 }
 146
 147 static int __devexit max8925_onkey_remove(struct platform_device *pdev)
 148 {
 149         struct max8925_onkey_info *info = platform_get_drvdata(pdev);
 150
 151         free_irq(info->irq[0], info);
 152         free_irq(info->irq[1], info);
 153         input_unregister_device(info->idev);
 154         kfree(info);
 155
 156         platform_set_drvdata(pdev, NULL);
 157
 158         return 0;
 159 }
 160
 161 static struct platform_driver max8925_onkey_driver = {
 162         .driver         = {
 163                 .name   = "max8925-onkey",
 164                 .owner  = THIS_MODULE,
 165         },
 166         .probe          = max8925_onkey_probe,
 167         .remove         = __devexit_p(max8925_onkey_remove),
 168 };
 169
 170 static int __init max8925_onkey_init(void)
 171 {
 172         return platform_driver_register(&max8925_onkey_driver);
 173 }
 174 module_init(max8925_onkey_init);
 175
 176 static void __exit max8925_onkey_exit(void)
 177 {
 178         platform_driver_unregister(&max8925_onkey_driver);
 179 }
 180 module_exit(max8925_onkey_exit);
 181
 182 MODULE_DESCRIPTION("Maxim MAX8925 ONKEY driver");
 183 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
 184 MODULE_LICENSE("GPL");