drivers/input/misc/max8925_onkey.c

   1 /**
   2  * 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 #include <linux/device.h>
  30
  31 #define SW_INPUT                (1 << 7)        /* 0/1 -- up/down */
  32 #define HARDRESET_EN            (1 << 7)
  33 #define PWREN_EN                (1 << 7)
  34
  35 struct max8925_onkey_info {
  36         struct input_dev        *idev;
  37         struct i2c_client       *i2c;
  38         struct device           *dev;
  39         unsigned int            irq[2];
  40 };
  41
  42 /*
  43  * MAX8925 gives us an interrupt when ONKEY is pressed or released.
  44  * max8925_set_bits() operates I2C bus and may sleep. So implement
  45  * it in thread IRQ handler.
  46  */
  47 static irqreturn_t max8925_onkey_handler(int irq, void *data)
  48 {
  49         struct max8925_onkey_info *info = data;
  50         int state;
  51
  52         state = max8925_reg_read(info->i2c, MAX8925_ON_OFF_STATUS);
  53
  54         input_report_key(info->idev, KEY_POWER, state & SW_INPUT);
  55         input_sync(info->idev);
  56
  57         dev_dbg(info->dev, "onkey state:%d\n", state);
  58
  59         /* Enable hardreset to halt if system isn't shutdown on time */
  60         max8925_set_bits(info->i2c, MAX8925_SYSENSEL,
  61                          HARDRESET_EN, HARDRESET_EN);
  62
  63         return IRQ_HANDLED;
  64 }
  65
  66 static int max8925_onkey_probe(struct platform_device *pdev)
  67 {
  68         struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
  69         struct max8925_onkey_info *info;
  70         struct input_dev *input;
  71         int irq[2], error;
  72
  73         irq[0] = platform_get_irq(pdev, 0);
  74         if (irq[0] < 0)
  75                 return -EINVAL;
  76
  77         irq[1] = platform_get_irq(pdev, 1);
  78         if (irq[1] < 0)
  79                 return -EINVAL;
  80
  81         info = devm_kzalloc(&pdev->dev, sizeof(struct max8925_onkey_info),
  82                             GFP_KERNEL);
  83         if (!info)
  84                 return -ENOMEM;
  85
  86         input = devm_input_allocate_device(&pdev->dev);
  87         if (!input)
  88                 return -ENOMEM;
  89
  90         info->idev = input;
  91         info->i2c = chip->i2c;
  92         info->dev = &pdev->dev;
  93         info->irq[0] = irq[0];
  94         info->irq[1] = irq[1];
  95
  96         input->name = "max8925_on";
  97         input->phys = "max8925_on/input0";
  98         input->id.bustype = BUS_I2C;
  99         input->dev.parent = &pdev->dev;
 100         input_set_capability(input, EV_KEY, KEY_POWER);
 101
 102         error = devm_request_threaded_irq(&pdev->dev, irq[0], NULL,
 103                                           max8925_onkey_handler, IRQF_ONESHOT,
 104                                           "onkey-down", info);
 105         if (error < 0) {
 106                 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
 107                         irq[0], error);
 108                 return error;
 109         }
 110
 111         error = devm_request_threaded_irq(&pdev->dev, irq[1], NULL,
 112                                           max8925_onkey_handler, IRQF_ONESHOT,
 113                                           "onkey-up", info);
 114         if (error < 0) {
 115                 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
 116                         irq[1], error);
 117                 return error;
 118         }
 119
 120         error = input_register_device(info->idev);
 121         if (error) {
 122                 dev_err(chip->dev, "Can't register input device: %d\n", error);
 123                 return error;
 124         }
 125
 126         platform_set_drvdata(pdev, info);
 127         device_init_wakeup(&pdev->dev, 1);
 128
 129         return 0;
 130 }
 131
 132 static int __maybe_unused max8925_onkey_suspend(struct device *dev)
 133 {
 134         struct platform_device *pdev = to_platform_device(dev);
 135         struct max8925_onkey_info *info = platform_get_drvdata(pdev);
 136         struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
 137
 138         if (device_may_wakeup(dev)) {
 139                 chip->wakeup_flag |= 1 << info->irq[0];
 140                 chip->wakeup_flag |= 1 << info->irq[1];
 141         }
 142
 143         return 0;
 144 }
 145
 146 static int __maybe_unused max8925_onkey_resume(struct device *dev)
 147 {
 148         struct platform_device *pdev = to_platform_device(dev);
 149         struct max8925_onkey_info *info = platform_get_drvdata(pdev);
 150         struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
 151
 152         if (device_may_wakeup(dev)) {
 153                 chip->wakeup_flag &= ~(1 << info->irq[0]);
 154                 chip->wakeup_flag &= ~(1 << info->irq[1]);
 155         }
 156
 157         return 0;
 158 }
 159
 160 static SIMPLE_DEV_PM_OPS(max8925_onkey_pm_ops, max8925_onkey_suspend, max8925_onkey_resume);
 161
 162 static struct platform_driver max8925_onkey_driver = {
 163         .driver         = {
 164                 .name   = "max8925-onkey",
 165                 .pm     = &max8925_onkey_pm_ops,
 166         },
 167         .probe          = max8925_onkey_probe,
 168 };
 169 module_platform_driver(max8925_onkey_driver);
 170
 171 MODULE_DESCRIPTION("Maxim MAX8925 ONKEY driver");
 172 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
 173 MODULE_LICENSE("GPL");