drivers/input/misc/pm8xxx-vibrator.c

   1 /* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License version 2 and
   5  * only version 2 as published by the Free Software Foundation.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/kernel.h>
  15 #include <linux/errno.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/input.h>
  18 #include <linux/slab.h>
  19 #include <linux/regmap.h>
  20
  21 #define VIB_DRV                 0x4A
  22
  23 #define VIB_DRV_SEL_MASK        0xf8
  24 #define VIB_DRV_SEL_SHIFT       0x03
  25 #define VIB_DRV_EN_MANUAL_MASK  0xfc
  26
  27 #define VIB_MAX_LEVEL_mV        (3100)
  28 #define VIB_MIN_LEVEL_mV        (1200)
  29 #define VIB_MAX_LEVELS          (VIB_MAX_LEVEL_mV - VIB_MIN_LEVEL_mV)
  30
  31 #define MAX_FF_SPEED            0xff
  32
  33 /**
  34  * struct pm8xxx_vib - structure to hold vibrator data
  35  * @vib_input_dev: input device supporting force feedback
  36  * @work: work structure to set the vibration parameters
  37  * @regmap: regmap for register read/write
  38  * @speed: speed of vibration set from userland
  39  * @active: state of vibrator
  40  * @level: level of vibration to set in the chip
  41  * @reg_vib_drv: VIB_DRV register value
  42  */
  43 struct pm8xxx_vib {
  44         struct input_dev *vib_input_dev;
  45         struct work_struct work;
  46         struct regmap *regmap;
  47         int speed;
  48         int level;
  49         bool active;
  50         u8  reg_vib_drv;
  51 };
  52
  53 /**
  54  * pm8xxx_vib_set - handler to start/stop vibration
  55  * @vib: pointer to vibrator structure
  56  * @on: state to set
  57  */
  58 static int pm8xxx_vib_set(struct pm8xxx_vib *vib, bool on)
  59 {
  60         int rc;
  61         unsigned int val = vib->reg_vib_drv;
  62
  63         if (on)
  64                 val |= ((vib->level << VIB_DRV_SEL_SHIFT) & VIB_DRV_SEL_MASK);
  65         else
  66                 val &= ~VIB_DRV_SEL_MASK;
  67
  68         rc = regmap_write(vib->regmap, VIB_DRV, val);
  69         if (rc < 0)
  70                 return rc;
  71
  72         vib->reg_vib_drv = val;
  73         return 0;
  74 }
  75
  76 /**
  77  * pm8xxx_work_handler - worker to set vibration level
  78  * @work: pointer to work_struct
  79  */
  80 static void pm8xxx_work_handler(struct work_struct *work)
  81 {
  82         struct pm8xxx_vib *vib = container_of(work, struct pm8xxx_vib, work);
  83         int rc;
  84         unsigned int val;
  85
  86         rc = regmap_read(vib->regmap, VIB_DRV, &val);
  87         if (rc < 0)
  88                 return;
  89
  90         /*
  91          * pmic vibrator supports voltage ranges from 1.2 to 3.1V, so
  92          * scale the level to fit into these ranges.
  93          */
  94         if (vib->speed) {
  95                 vib->active = true;
  96                 vib->level = ((VIB_MAX_LEVELS * vib->speed) / MAX_FF_SPEED) +
  97                                                 VIB_MIN_LEVEL_mV;
  98                 vib->level /= 100;
  99         } else {
 100                 vib->active = false;
 101                 vib->level = VIB_MIN_LEVEL_mV / 100;
 102         }
 103
 104         pm8xxx_vib_set(vib, vib->active);
 105 }
 106
 107 /**
 108  * pm8xxx_vib_close - callback of input close callback
 109  * @dev: input device pointer
 110  *
 111  * Turns off the vibrator.
 112  */
 113 static void pm8xxx_vib_close(struct input_dev *dev)
 114 {
 115         struct pm8xxx_vib *vib = input_get_drvdata(dev);
 116
 117         cancel_work_sync(&vib->work);
 118         if (vib->active)
 119                 pm8xxx_vib_set(vib, false);
 120 }
 121
 122 /**
 123  * pm8xxx_vib_play_effect - function to handle vib effects.
 124  * @dev: input device pointer
 125  * @data: data of effect
 126  * @effect: effect to play
 127  *
 128  * Currently this driver supports only rumble effects.
 129  */
 130 static int pm8xxx_vib_play_effect(struct input_dev *dev, void *data,
 131                                   struct ff_effect *effect)
 132 {
 133         struct pm8xxx_vib *vib = input_get_drvdata(dev);
 134
 135         vib->speed = effect->u.rumble.strong_magnitude >> 8;
 136         if (!vib->speed)
 137                 vib->speed = effect->u.rumble.weak_magnitude >> 9;
 138
 139         schedule_work(&vib->work);
 140
 141         return 0;
 142 }
 143
 144 static int pm8xxx_vib_probe(struct platform_device *pdev)
 145
 146 {
 147         struct pm8xxx_vib *vib;
 148         struct input_dev *input_dev;
 149         int error;
 150         unsigned int val;
 151
 152         vib = devm_kzalloc(&pdev->dev, sizeof(*vib), GFP_KERNEL);
 153         if (!vib)
 154                 return -ENOMEM;
 155
 156         vib->regmap = dev_get_regmap(pdev->dev.parent, NULL);
 157         if (!vib->regmap)
 158                 return -ENODEV;
 159
 160         input_dev = devm_input_allocate_device(&pdev->dev);
 161         if (!input_dev)
 162                 return -ENOMEM;
 163
 164         INIT_WORK(&vib->work, pm8xxx_work_handler);
 165         vib->vib_input_dev = input_dev;
 166
 167         /* operate in manual mode */
 168         error = regmap_read(vib->regmap, VIB_DRV, &val);
 169         if (error < 0)
 170                 return error;
 171
 172         val &= ~VIB_DRV_EN_MANUAL_MASK;
 173         error = regmap_write(vib->regmap, VIB_DRV, val);
 174         if (error < 0)
 175                 return error;
 176
 177         vib->reg_vib_drv = val;
 178
 179         input_dev->name = "pm8xxx_vib_ffmemless";
 180         input_dev->id.version = 1;
 181         input_dev->close = pm8xxx_vib_close;
 182         input_set_drvdata(input_dev, vib);
 183         input_set_capability(vib->vib_input_dev, EV_FF, FF_RUMBLE);
 184
 185         error = input_ff_create_memless(input_dev, NULL,
 186                                         pm8xxx_vib_play_effect);
 187         if (error) {
 188                 dev_err(&pdev->dev,
 189                         "couldn't register vibrator as FF device\n");
 190                 return error;
 191         }
 192
 193         error = input_register_device(input_dev);
 194         if (error) {
 195                 dev_err(&pdev->dev, "couldn't register input device\n");
 196                 return error;
 197         }
 198
 199         platform_set_drvdata(pdev, vib);
 200         return 0;
 201 }
 202
 203 #ifdef CONFIG_PM_SLEEP
 204 static int pm8xxx_vib_suspend(struct device *dev)
 205 {
 206         struct pm8xxx_vib *vib = dev_get_drvdata(dev);
 207
 208         /* Turn off the vibrator */
 209         pm8xxx_vib_set(vib, false);
 210
 211         return 0;
 212 }
 213 #endif
 214
 215 static SIMPLE_DEV_PM_OPS(pm8xxx_vib_pm_ops, pm8xxx_vib_suspend, NULL);
 216
 217 static struct platform_driver pm8xxx_vib_driver = {
 218         .probe          = pm8xxx_vib_probe,
 219         .driver         = {
 220                 .name   = "pm8xxx-vib",
 221                 .owner  = THIS_MODULE,
 222                 .pm     = &pm8xxx_vib_pm_ops,
 223         },
 224 };
 225 module_platform_driver(pm8xxx_vib_driver);
 226
 227 MODULE_ALIAS("platform:pm8xxx_vib");
 228 MODULE_DESCRIPTION("PMIC8xxx vibrator driver based on ff-memless framework");
 229 MODULE_LICENSE("GPL v2");
 230 MODULE_AUTHOR("Amy Maloche <amaloche@codeaurora.org>");