pm8xxx-vibrator.c
/* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/platform_device.h>
#include <linux/input.h>
#include <linux/slab.h>
#include <linux/mfd/pm8xxx/core.h>
#define VIB_DRV 0x4A
#define VIB_DRV_SEL_MASK 0xf8
#define VIB_DRV_SEL_SHIFT 0x03
#define VIB_DRV_EN_MANUAL_MASK 0xfc
#define VIB_MAX_LEVEL_mV (3100)
#define VIB_MIN_LEVEL_mV (1200)
#define VIB_MAX_LEVELS (VIB_MAX_LEVEL_mV - VIB_MIN_LEVEL_mV)
#define MAX_FF_SPEED 0xff
/**
* struct pm8xxx_vib - structure to hold vibrator data
* @vib_input_dev: input device supporting force feedback
* @work: work structure to set the vibration parameters
* @dev: device supporting force feedback
* @speed: speed of vibration set from userland
* @active: state of vibrator
* @level: level of vibration to set in the chip
* @reg_vib_drv: VIB_DRV register value
*/
struct pm8xxx_vib {
struct input_dev *vib_input_dev;
struct work_struct work;
struct device *dev;
int speed;
int level;
bool active;
u8 reg_vib_drv;
};
/**
* pm8xxx_vib_read_u8 - helper to read a byte from pmic chip
* @vib: pointer to vibrator structure
* @data: placeholder for data to be read
* @reg: register address
*/
static int pm8xxx_vib_read_u8(struct pm8xxx_vib *vib,
u8 *data, u16 reg)
{
int rc;
rc = pm8xxx_readb(vib->dev->parent, reg, data);
if (rc < 0)
dev_warn(vib->dev, "Error reading pm8xxx reg 0x%x(0x%x)\n",
reg, rc);
return rc;
}
/**
* pm8xxx_vib_write_u8 - helper to write a byte to pmic chip
* @vib: pointer to vibrator structure
* @data: data to write
* @reg: register address
*/
static int pm8xxx_vib_write_u8(struct pm8xxx_vib *vib,
u8 data, u16 reg)
{
int rc;
rc = pm8xxx_writeb(vib->dev->parent, reg, data);
if (rc < 0)
dev_warn(vib->dev, "Error writing pm8xxx reg 0x%x(0x%x)\n",
reg, rc);
return rc;
}
/**
* pm8xxx_vib_set - handler to start/stop vibration
* @vib: pointer to vibrator structure
* @on: state to set
*/
static int pm8xxx_vib_set(struct pm8xxx_vib *vib, bool on)
{
int rc;
u8 val = vib->reg_vib_drv;
if (on)
val |= ((vib->level << VIB_DRV_SEL_SHIFT) & VIB_DRV_SEL_MASK);
else
val &= ~VIB_DRV_SEL_MASK;
rc = pm8xxx_vib_write_u8(vib, val, VIB_DRV);
if (rc < 0)
return rc;
vib->reg_vib_drv = val;
return 0;
}
/**
* pm8xxx_work_handler - worker to set vibration level
* @work: pointer to work_struct
*/
static void pm8xxx_work_handler(struct work_struct *work)
{
struct pm8xxx_vib *vib = container_of(work, struct pm8xxx_vib, work);
int rc;
u8 val;
rc = pm8xxx_vib_read_u8(vib, &val, VIB_DRV);
if (rc < 0)
return;
/*
* pmic vibrator supports voltage ranges from 1.2 to 3.1V, so
* scale the level to fit into these ranges.
*/
if (vib->speed) {
vib->active = true;
vib->level = ((VIB_MAX_LEVELS * vib->speed) / MAX_FF_SPEED) +
VIB_MIN_LEVEL_mV;
vib->level /= 100;
} else {
vib->active = false;
vib->level = VIB_MIN_LEVEL_mV / 100;
}
pm8xxx_vib_set(vib, vib->active);
}
/**
* pm8xxx_vib_close - callback of input close callback
* @dev: input device pointer
*
* Turns off the vibrator.
*/
static void pm8xxx_vib_close(struct input_dev *dev)
{
struct pm8xxx_vib *vib = input_get_drvdata(dev);
cancel_work_sync(&vib->work);
if (vib->active)
pm8xxx_vib_set(vib, false);
}
/**
* pm8xxx_vib_play_effect - function to handle vib effects.
* @dev: input device pointer
* @data: data of effect
* @effect: effect to play
*
* Currently this driver supports only rumble effects.
*/
static int pm8xxx_vib_play_effect(struct input_dev *dev, void *data,
struct ff_effect *effect)
{
struct pm8xxx_vib *vib = input_get_drvdata(dev);
vib->speed = effect->u.rumble.strong_magnitude >> 8;
if (!vib->speed)
vib->speed = effect->u.rumble.weak_magnitude >> 9;
schedule_work(&vib->work);
return 0;
}
static int pm8xxx_vib_probe(struct platform_device *pdev)
{
struct pm8xxx_vib *vib;
struct input_dev *input_dev;
int error;
u8 val;
vib = kzalloc(sizeof(*vib), GFP_KERNEL);
input_dev = input_allocate_device();
if (!vib || !input_dev) {
dev_err(&pdev->dev, "couldn't allocate memory\n");
error = -ENOMEM;
goto err_free_mem;
}
INIT_WORK(&vib->work, pm8xxx_work_handler);
vib->dev = &pdev->dev;
vib->vib_input_dev = input_dev;
/* operate in manual mode */
error = pm8xxx_vib_read_u8(vib, &val, VIB_DRV);
if (error < 0)
goto err_free_mem;
val &= ~VIB_DRV_EN_MANUAL_MASK;
error = pm8xxx_vib_write_u8(vib, val, VIB_DRV);
if (error < 0)
goto err_free_mem;
vib->reg_vib_drv = val;
input_dev->name = "pm8xxx_vib_ffmemless";
input_dev->id.version = 1;
input_dev->dev.parent = &pdev->dev;
input_dev->close = pm8xxx_vib_close;
input_set_drvdata(input_dev, vib);
input_set_capability(vib->vib_input_dev, EV_FF, FF_RUMBLE);
error = input_ff_create_memless(input_dev, NULL,
pm8xxx_vib_play_effect);
if (error) {
dev_err(&pdev->dev,
"couldn't register vibrator as FF device\n");
goto err_free_mem;
}
error = input_register_device(input_dev);
if (error) {
dev_err(&pdev->dev, "couldn't register input device\n");
goto err_destroy_memless;
}
platform_set_drvdata(pdev, vib);
return 0;
err_destroy_memless:
input_ff_destroy(input_dev);
err_free_mem:
input_free_device(input_dev);
kfree(vib);
return error;
}
static int pm8xxx_vib_remove(struct platform_device *pdev)
{
struct pm8xxx_vib *vib = platform_get_drvdata(pdev);
input_unregister_device(vib->vib_input_dev);
kfree(vib);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int pm8xxx_vib_suspend(struct device *dev)
{
struct pm8xxx_vib *vib = dev_get_drvdata(dev);
/* Turn off the vibrator */
pm8xxx_vib_set(vib, false);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(pm8xxx_vib_pm_ops, pm8xxx_vib_suspend, NULL);
static struct platform_driver pm8xxx_vib_driver = {
.probe = pm8xxx_vib_probe,
.remove = pm8xxx_vib_remove,
.driver = {
.name = "pm8xxx-vib",
.owner = THIS_MODULE,
.pm = &pm8xxx_vib_pm_ops,
},
};
module_platform_driver(pm8xxx_vib_driver);
MODULE_ALIAS("platform:pm8xxx_vib");
MODULE_DESCRIPTION("PMIC8xxx vibrator driver based on ff-memless framework");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Amy Maloche <amaloche@codeaurora.org>");