drivers/input/misc/twl6030-pwrbutton.c

   1 /**
   2  * twl6030-pwrbutton.c - TWL6030 Power Button Input Driver
   3  *
   4  * Copyright (C) 2011
   5  *
   6  * Written by Dan Murphy <DMurphy@ti.com>
   7  *
   8  * This file is subject to the terms and conditions of the GNU General
   9  * Public License. See the file "COPYING" in the main directory of this
  10  * archive for more details.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  *
  21  * Derived Work from: twl4030-pwrbutton.c from
  22  * Peter De Schrijver <peter.de-schrijver@nokia.com>
  23  * Felipe Balbi <felipe.balbi@nokia.com>
  24  *
  25  */
  26
  27 #include <linux/module.h>
  28 #include <linux/init.h>
  29 #include <linux/kernel.h>
  30 #include <linux/errno.h>
  31 #include <linux/input.h>
  32 #include <linux/interrupt.h>
  33 #include <linux/platform_device.h>
  34 #include <linux/slab.h>
  35 #include <linux/i2c/twl.h>
  36 #include <linux/delay.h>
  37
  38 #define PWR_PWRON_IRQ (1 << 0)
  39 #define STS_HW_CONDITIONS 0x21
  40
  41 struct twl6030_pwr_button {
  42         struct input_dev *input_dev;
  43         struct device           *dev;
  44         struct mutex            irq_lock;
  45         int report_key;
  46 };
  47
  48 static inline int twl6030_readb(struct twl6030_pwr_button *twl,
  49                 u8 module, u8 address)
  50 {
  51         u8 data = 0;
  52         int ret = 0;
  53
  54         ret = twl_i2c_read_u8(module, &data, address);
  55         if (ret >= 0)
  56                 ret = data;
  57         else
  58                 dev_dbg(twl->dev,
  59                         "TWL6030:readb[0x%x,0x%x] Error %d\n",
  60                                         module, address, ret);
  61
  62         return ret;
  63 }
  64
  65 static inline int twl6030_writeb(struct twl6030_pwr_button *twl, u8 module,
  66                                                 u8 data, u8 address)
  67 {
  68         int ret = 0;
  69
  70         ret = twl_i2c_write_u8(module, data, address);
  71         if (ret < 0)
  72                 dev_dbg(twl->dev,
  73                         "TWL6030:Write[0x%x] Error %d\n", address, ret);
  74         return ret;
  75 }
  76
  77 static irqreturn_t powerbutton_irq(int irq, void *_pwr)
  78 {
  79         struct twl6030_pwr_button *pwr = _pwr;
  80         int hw_state;
  81         int pwr_val;
  82         static int prev_hw_state = 0xFFFF;
  83         static int push_release_flag = 0 ;
  84
  85         mutex_lock(& pwr ->irq_lock);
  86         hw_state = twl6030_readb(pwr, TWL6030_MODULE_ID0, STS_HW_CONDITIONS);
  87         pwr_val = !(hw_state & PWR_PWRON_IRQ);
  88
  89         if ((prev_hw_state != pwr_val) && (prev_hw_state != 0xFFFF)) {
  90                 push_release_flag = 0;
  91                 input_report_key(pwr->input_dev, pwr->report_key, pwr_val);
  92                 input_sync(pwr->input_dev);
  93         } else if (!push_release_flag) {
  94                 push_release_flag = 1;
  95                 if(prev_hw_state != 0xFFFF){
  96                         input_report_key(pwr->input_dev, pwr->report_key, !pwr_val);
  97                         input_sync(pwr->input_dev);
  98
  99                         msleep(20);
 100                         input_report_key(pwr->input_dev, pwr->report_key, pwr_val);
 101                         input_sync(pwr->input_dev);
 102                 }
 103                 else    {
 104                         input_report_key(pwr->input_dev, pwr->report_key, pwr_val);
 105                         input_sync(pwr->input_dev);
 106                 }
 107         } else
 108                 push_release_flag = 0;
 109
 110         prev_hw_state = pwr_val;
 111         mutex_unlock(& pwr ->irq_lock);
 112
 113         return IRQ_HANDLED;
 114 }
 115
 116 static int __devinit twl6030_pwrbutton_probe(struct platform_device *pdev)
 117 {
 118         struct twl6030_pwr_button *pwr_button;
 119         int irq = platform_get_irq(pdev, 0);
 120         int err = -ENODEV;
 121
 122         pr_info("%s: Enter\n", __func__);
 123         pwr_button = kzalloc(sizeof(struct twl6030_pwr_button), GFP_KERNEL);
 124         if (!pwr_button)
 125                 return -ENOMEM;
 126
 127         pwr_button->input_dev = input_allocate_device();
 128         if (!pwr_button->input_dev) {
 129                 dev_dbg(&pdev->dev, "Can't allocate power button\n");
 130                 goto input_error;
 131         }
 132
 133         __set_bit(EV_KEY, pwr_button->input_dev->evbit);
 134
 135         pwr_button->report_key = KEY_POWER;
 136         pwr_button->dev = &pdev->dev;
 137         pwr_button->input_dev->evbit[0] = BIT_MASK(EV_KEY);
 138         pwr_button->input_dev->keybit[BIT_WORD(pwr_button->report_key)] =
 139                         BIT_MASK(pwr_button->report_key);
 140         pwr_button->input_dev->name = "twl6030_pwrbutton";
 141         pwr_button->input_dev->phys = "twl6030_pwrbutton/input0";
 142         pwr_button->input_dev->dev.parent = &pdev->dev;
 143
 144         err = request_threaded_irq(irq, NULL, powerbutton_irq,
 145                         IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
 146                         "twl6030_pwrbutton", pwr_button);
 147         if (err < 0) {
 148                 dev_dbg(&pdev->dev, "Can't get IRQ for pwrbutton: %d\n", err);
 149                 goto free_input_dev;
 150         }
 151
 152         err = input_register_device(pwr_button->input_dev);
 153         if (err) {
 154                 dev_dbg(&pdev->dev, "Can't register power button: %d\n", err);
 155                 goto free_irq;
 156         }
 157         mutex_init(&pwr_button->irq_lock);
 158
 159         twl6030_interrupt_unmask(0x01, REG_INT_MSK_LINE_A);
 160         twl6030_interrupt_unmask(0x01, REG_INT_MSK_STS_A);
 161
 162         platform_set_drvdata(pdev, pwr_button);
 163
 164         return 0;
 165
 166 free_irq:
 167         free_irq(irq, NULL);
 168 free_input_dev:
 169         input_free_device(pwr_button->input_dev);
 170 input_error:
 171         kfree(pwr_button);
 172         return err;
 173 }
 174
 175 static int __devexit twl6030_pwrbutton_remove(struct platform_device *pdev)
 176 {
 177         struct input_dev *pwr = platform_get_drvdata(pdev);
 178         int irq = platform_get_irq(pdev, 0);
 179
 180         free_irq(irq, pwr);
 181         input_unregister_device(pwr);
 182
 183         return 0;
 184 }
 185
 186 struct platform_driver twl6030_pwrbutton_driver = {
 187         .probe          = twl6030_pwrbutton_probe,
 188         .remove         = __devexit_p(twl6030_pwrbutton_remove),
 189         .driver         = {
 190                 .name   = "twl6030_pwrbutton",
 191                 .owner  = THIS_MODULE,
 192         },
 193 };
 194
 195 static int __init twl6030_pwrbutton_init(void)
 196 {
 197         return platform_driver_register(&twl6030_pwrbutton_driver);
 198 }
 199 module_init(twl6030_pwrbutton_init);
 200
 201 static void __exit twl6030_pwrbutton_exit(void)
 202 {
 203         platform_driver_unregister(&twl6030_pwrbutton_driver);
 204 }
 205 module_exit(twl6030_pwrbutton_exit);
 206
 207 MODULE_ALIAS("platform:twl6030_pwrbutton");
 208 MODULE_DESCRIPTION("Triton2 Power Button");
 209 MODULE_LICENSE("GPL");
 210 MODULE_AUTHOR("Dan Murphy <DMurphy@ti.com>");