LXR linux/drivers/input/misc/max8925

   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
  35struct 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 */
  47static 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
  66static 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
 136static 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
 150static 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
 164static SIMPLE_DEV_PM_OPS(max8925_onkey_pm_ops, max8925_onkey_suspend, max8925_onkey_resume);
 165
 166static 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};
 173module_platform_driver(max8925_onkey_driver);
 174
 175MODULE_DESCRIPTION("Maxim MAX8925 ONKEY driver");
 176MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
 177MODULE_LICENSE("GPL");
 178