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/init.h>
  15 #include <linux/kernel.h>
  16 #include <linux/errno.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/input.h>
  19 #include <linux/slab.h>
  20 #include <linux/mfd/pm8xxx/core.h>
  21
  22 #define VIB_DRV                 0x4A
  23
  24 #define VIB_DRV_SEL_MASK        0xf8
  25 #define VIB_DRV_SEL_SHIFT       0x03
  26 #define VIB_DRV_EN_MANUAL_MASK  0xfc
  27
  28 #define VIB_MAX_LEVEL_mV        (3100)
  29 #define VIB_MIN_LEVEL_mV        (1200)
  30 #define VIB_MAX_LEVELS          (VIB_MAX_LEVEL_mV - VIB_MIN_LEVEL_mV)
  31
  32 #define MAX_FF_SPEED            0xff
  33
  34 /**
  35  * struct pm8xxx_vib - structure to hold vibrator data
  36  * @vib_input_dev: input device supporting force feedback
  37  * @work: work structure to set the vibration parameters
  38  * @dev: device supporting force feedback
  39  * @speed: speed of vibration set from userland
  40  * @active: state of vibrator
  41  * @level: level of vibration to set in the chip
  42  * @reg_vib_drv: VIB_DRV register value
  43  */
  44 struct pm8xxx_vib {
  45         struct input_dev *vib_input_dev;
  46         struct work_struct work;
  47         struct device *dev;
  48         int speed;
  49         int level;
  50         bool active;
  51         u8  reg_vib_drv;
  52 };
  53
  54 /**
  55  * pm8xxx_vib_read_u8 - helper to read a byte from pmic chip
  56  * @vib: pointer to vibrator structure
  57  * @data: placeholder for data to be read
  58  * @reg: register address
  59  */
  60 static int pm8xxx_vib_read_u8(struct pm8xxx_vib *vib,
  61                                  u8 *data, u16 reg)
  62 {
  63         int rc;
  64
  65         rc = pm8xxx_readb(vib->dev->parent, reg, data);
  66         if (rc < 0)
  67                 dev_warn(vib->dev, "Error reading pm8xxx reg 0x%x(0x%x)\n",
  68                                 reg, rc);
  69         return rc;
  70 }
  71
  72 /**
  73  * pm8xxx_vib_write_u8 - helper to write a byte to pmic chip
  74  * @vib: pointer to vibrator structure
  75  * @data: data to write
  76  * @reg: register address
  77  */
  78 static int pm8xxx_vib_write_u8(struct pm8xxx_vib *vib,
  79                                  u8 data, u16 reg)
  80 {
  81         int rc;
  82
  83         rc = pm8xxx_writeb(vib->dev->parent, reg, data);
  84         if (rc < 0)
  85                 dev_warn(vib->dev, "Error writing pm8xxx reg 0x%x(0x%x)\n",
  86                                 reg, rc);
  87         return rc;
  88 }
  89
  90 /**
  91  * pm8xxx_vib_set - handler to start/stop vibration
  92  * @vib: pointer to vibrator structure
  93  * @on: state to set
  94  */
  95 static int pm8xxx_vib_set(struct pm8xxx_vib *vib, bool on)
  96 {
  97         int rc;
  98         u8 val = vib->reg_vib_drv;
  99
 100         if (on)
 101                 val |= ((vib->level << VIB_DRV_SEL_SHIFT) & VIB_DRV_SEL_MASK);
 102         else
 103                 val &= ~VIB_DRV_SEL_MASK;
 104
 105         rc = pm8xxx_vib_write_u8(vib, val, VIB_DRV);
 106         if (rc < 0)
 107                 return rc;
 108
 109         vib->reg_vib_drv = val;
 110         return 0;
 111 }
 112
 113 /**
 114  * pm8xxx_work_handler - worker to set vibration level
 115  * @work: pointer to work_struct
 116  */
 117 static void pm8xxx_work_handler(struct work_struct *work)
 118 {
 119         struct pm8xxx_vib *vib = container_of(work, struct pm8xxx_vib, work);
 120         int rc;
 121         u8 val;
 122
 123         rc = pm8xxx_vib_read_u8(vib, &val, VIB_DRV);
 124         if (rc < 0)
 125                 return;
 126
 127         /*
 128          * pmic vibrator supports voltage ranges from 1.2 to 3.1V, so
 129          * scale the level to fit into these ranges.
 130          */
 131         if (vib->speed) {
 132                 vib->active = true;
 133                 vib->level = ((VIB_MAX_LEVELS * vib->speed) / MAX_FF_SPEED) +
 134                                                 VIB_MIN_LEVEL_mV;
 135                 vib->level /= 100;
 136         } else {
 137                 vib->active = false;
 138                 vib->level = VIB_MIN_LEVEL_mV / 100;
 139         }
 140
 141         pm8xxx_vib_set(vib, vib->active);
 142 }
 143
 144 /**
 145  * pm8xxx_vib_close - callback of input close callback
 146  * @dev: input device pointer
 147  *
 148  * Turns off the vibrator.
 149  */
 150 static void pm8xxx_vib_close(struct input_dev *dev)
 151 {
 152         struct pm8xxx_vib *vib = input_get_drvdata(dev);
 153
 154         cancel_work_sync(&vib->work);
 155         if (vib->active)
 156                 pm8xxx_vib_set(vib, false);
 157 }
 158
 159 /**
 160  * pm8xxx_vib_play_effect - function to handle vib effects.
 161  * @dev: input device pointer
 162  * @data: data of effect
 163  * @effect: effect to play
 164  *
 165  * Currently this driver supports only rumble effects.
 166  */
 167 static int pm8xxx_vib_play_effect(struct input_dev *dev, void *data,
 168                                   struct ff_effect *effect)
 169 {
 170         struct pm8xxx_vib *vib = input_get_drvdata(dev);
 171
 172         vib->speed = effect->u.rumble.strong_magnitude >> 8;
 173         if (!vib->speed)
 174                 vib->speed = effect->u.rumble.weak_magnitude >> 9;
 175
 176         schedule_work(&vib->work);
 177
 178         return 0;
 179 }
 180
 181 static int pm8xxx_vib_probe(struct platform_device *pdev)
 182
 183 {
 184         struct pm8xxx_vib *vib;
 185         struct input_dev *input_dev;
 186         int error;
 187         u8 val;
 188
 189         vib = kzalloc(sizeof(*vib), GFP_KERNEL);
 190         input_dev = input_allocate_device();
 191         if (!vib || !input_dev) {
 192                 dev_err(&pdev->dev, "couldn't allocate memory\n");
 193                 error = -ENOMEM;
 194                 goto err_free_mem;
 195         }
 196
 197         INIT_WORK(&vib->work, pm8xxx_work_handler);
 198         vib->dev = &pdev->dev;
 199         vib->vib_input_dev = input_dev;
 200
 201         /* operate in manual mode */
 202         error = pm8xxx_vib_read_u8(vib, &val, VIB_DRV);
 203         if (error < 0)
 204                 goto err_free_mem;
 205         val &= ~VIB_DRV_EN_MANUAL_MASK;
 206         error = pm8xxx_vib_write_u8(vib, val, VIB_DRV);
 207         if (error < 0)
 208                 goto err_free_mem;
 209
 210         vib->reg_vib_drv = val;
 211
 212         input_dev->name = "pm8xxx_vib_ffmemless";
 213         input_dev->id.version = 1;
 214         input_dev->dev.parent = &pdev->dev;
 215         input_dev->close = pm8xxx_vib_close;
 216         input_set_drvdata(input_dev, vib);
 217         input_set_capability(vib->vib_input_dev, EV_FF, FF_RUMBLE);
 218
 219         error = input_ff_create_memless(input_dev, NULL,
 220                                         pm8xxx_vib_play_effect);
 221         if (error) {
 222                 dev_err(&pdev->dev,
 223                         "couldn't register vibrator as FF device\n");
 224                 goto err_free_mem;
 225         }
 226
 227         error = input_register_device(input_dev);
 228         if (error) {
 229                 dev_err(&pdev->dev, "couldn't register input device\n");
 230                 goto err_destroy_memless;
 231         }
 232
 233         platform_set_drvdata(pdev, vib);
 234         return 0;
 235
 236 err_destroy_memless:
 237         input_ff_destroy(input_dev);
 238 err_free_mem:
 239         input_free_device(input_dev);
 240         kfree(vib);
 241
 242         return error;
 243 }
 244
 245 static int pm8xxx_vib_remove(struct platform_device *pdev)
 246 {
 247         struct pm8xxx_vib *vib = platform_get_drvdata(pdev);
 248
 249         input_unregister_device(vib->vib_input_dev);
 250         kfree(vib);
 251
 252         return 0;
 253 }
 254
 255 #ifdef CONFIG_PM_SLEEP
 256 static int pm8xxx_vib_suspend(struct device *dev)
 257 {
 258         struct pm8xxx_vib *vib = dev_get_drvdata(dev);
 259
 260         /* Turn off the vibrator */
 261         pm8xxx_vib_set(vib, false);
 262
 263         return 0;
 264 }
 265 #endif
 266
 267 static SIMPLE_DEV_PM_OPS(pm8xxx_vib_pm_ops, pm8xxx_vib_suspend, NULL);
 268
 269 static struct platform_driver pm8xxx_vib_driver = {
 270         .probe          = pm8xxx_vib_probe,
 271         .remove         = pm8xxx_vib_remove,
 272         .driver         = {
 273                 .name   = "pm8xxx-vib",
 274                 .owner  = THIS_MODULE,
 275                 .pm     = &pm8xxx_vib_pm_ops,
 276         },
 277 };
 278 module_platform_driver(pm8xxx_vib_driver);
 279
 280 MODULE_ALIAS("platform:pm8xxx_vib");
 281 MODULE_DESCRIPTION("PMIC8xxx vibrator driver based on ff-memless framework");
 282 MODULE_LICENSE("GPL v2");
 283 MODULE_AUTHOR("Amy Maloche <amaloche@codeaurora.org>");