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                 dev_err(&pdev->dev, "No IRQ resource!\n");
  76                 return -EINVAL;
  77         }
  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 = devm_kzalloc(&pdev->dev, sizeof(struct max8925_onkey_info),
  86                             GFP_KERNEL);
  87         if (!info)
  88                 return -ENOMEM;
  89
  90         input = devm_input_allocate_device(&pdev->dev);
  91         if (!input)
  92                 return -ENOMEM;
  93
  94         info->idev = input;
  95         info->i2c = chip->i2c;
  96         info->dev = &pdev->dev;
  97         info->irq[0] = irq[0];
  98         info->irq[1] = irq[1];
  99
 100         input->name = "max8925_on";
 101         input->phys = "max8925_on/input0";
 102         input->id.bustype = BUS_I2C;
 103         input->dev.parent = &pdev->dev;
 104         input_set_capability(input, EV_KEY, KEY_POWER);
 105
 106         error = devm_request_threaded_irq(&pdev->dev, irq[0], NULL,
 107                                           max8925_onkey_handler, IRQF_ONESHOT,
 108                                           "onkey-down", info);
 109         if (error < 0) {
 110                 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
 111                         irq[0], error);
 112                 return error;
 113         }
 114
 115         error = devm_request_threaded_irq(&pdev->dev, irq[1], NULL,
 116                                           max8925_onkey_handler, IRQF_ONESHOT,
 117                                           "onkey-up", info);
 118         if (error < 0) {
 119                 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
 120                         irq[1], error);
 121                 return error;
 122         }
 123
 124         error = input_register_device(info->idev);
 125         if (error) {
 126                 dev_err(chip->dev, "Can't register input device: %d\n", error);
 127                 return error;
 128         }
 129
 130         platform_set_drvdata(pdev, info);
 131         device_init_wakeup(&pdev->dev, 1);
 132
 133         return 0;
 134 }
 135
 136 static int __maybe_unused max8925_onkey_suspend(struct device *dev)
 137 {
 138         struct platform_device *pdev = to_platform_device(dev);
 139         struct max8925_onkey_info *info = platform_get_drvdata(pdev);
 140         struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
 141
 142         if (device_may_wakeup(dev)) {
 143                 chip->wakeup_flag |= 1 << info->irq[0];
 144                 chip->wakeup_flag |= 1 << info->irq[1];
 145         }
 146
 147         return 0;
 148 }
 149
 150 static int __maybe_unused max8925_onkey_resume(struct device *dev)
 151 {
 152         struct platform_device *pdev = to_platform_device(dev);
 153         struct max8925_onkey_info *info = platform_get_drvdata(pdev);
 154         struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
 155
 156         if (device_may_wakeup(dev)) {
 157                 chip->wakeup_flag &= ~(1 << info->irq[0]);
 158                 chip->wakeup_flag &= ~(1 << info->irq[1]);
 159         }
 160
 161         return 0;
 162 }
 163
 164 static SIMPLE_DEV_PM_OPS(max8925_onkey_pm_ops, max8925_onkey_suspend, max8925_onkey_resume);
 165
 166 static struct platform_driver max8925_onkey_driver = {
 167         .driver         = {
 168                 .name   = "max8925-onkey",
 169                 .pm     = &max8925_onkey_pm_ops,
 170         },
 171         .probe          = max8925_onkey_probe,
 172 };
 173 module_platform_driver(max8925_onkey_driver);
 174
 175 MODULE_DESCRIPTION("Maxim MAX8925 ONKEY driver");
 176 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
 177 MODULE_LICENSE("GPL");