kevin/linux
1
Fork 0
Code
b85daa5324
linux/drivers/hwmon/lis3lv02d.c
Daniel Mack 8f3128e714 lis3: add click function 
The LIS302DL accelerometer chip has a 'click' feature which can be used to
detect sudden motion on any of the three axis.  Configuration data is
passed via spi platform_data and no action is taken if that's not
specified, so it won't harm any existing platform.

To make the configuration effective, the IRQ lines need to be set up
appropriately.  This patch also adds a way to do that from board support
code.

The DD_* definitions were factored out to an own enum because they are
specific to LIS3LV02D devices.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Eric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-16 19:47:57 -07:00

479 lines
13 KiB
C
Raw Blame History

/*
* lis3lv02d.c - ST LIS3LV02DL accelerometer driver
*
* Copyright (C) 2007-2008 Yan Burman
* Copyright (C) 2008 Eric Piel
* Copyright (C) 2008-2009 Pavel Machek
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/dmi.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/input-polldev.h>
#include <linux/delay.h>
#include <linux/wait.h>
#include <linux/poll.h>
#include <linux/freezer.h>
#include <linux/uaccess.h>
#include <linux/miscdevice.h>
#include <asm/atomic.h>
#include "lis3lv02d.h"
#define DRIVER_NAME "lis3lv02d"
/* joystick device poll interval in milliseconds */
#define MDPS_POLL_INTERVAL 50
/*
* The sensor can also generate interrupts (DRDY) but it's pretty pointless
* because their are generated even if the data do not change. So it's better
* to keep the interrupt for the free-fall event. The values are updated at
* 40Hz (at the lowest frequency), but as it can be pretty time consuming on
* some low processor, we poll the sensor only at 20Hz... enough for the
* joystick.
*/
struct lis3lv02d lis3_dev = {
.misc_wait = __WAIT_QUEUE_HEAD_INITIALIZER(lis3_dev.misc_wait),
};
EXPORT_SYMBOL_GPL(lis3_dev);
static s16 lis3lv02d_read_8(struct lis3lv02d *lis3, int reg)
{
s8 lo;
if (lis3->read(lis3, reg, &lo) < 0)
return 0;
return lo;
}
static s16 lis3lv02d_read_16(struct lis3lv02d *lis3, int reg)
{
u8 lo, hi;
lis3->read(lis3, reg - 1, &lo);
lis3->read(lis3, reg, &hi);
/* In "12 bit right justified" mode, bit 6, bit 7, bit 8 = bit 5 */
return (s16)((hi << 8) | lo);
}
/**
* lis3lv02d_get_axis - For the given axis, give the value converted
* @axis: 1,2,3 - can also be negative
* @hw_values: raw values returned by the hardware
*
* Returns the converted value.
*/
static inline int lis3lv02d_get_axis(s8 axis, int hw_values[3])
{
if (axis > 0)
return hw_values[axis - 1];
else
return -hw_values[-axis - 1];
}
/**
* lis3lv02d_get_xyz - Get X, Y and Z axis values from the accelerometer
* @lis3: pointer to the device struct
* @x: where to store the X axis value
* @y: where to store the Y axis value
* @z: where to store the Z axis value
*
* Note that 40Hz input device can eat up about 10% CPU at 800MHZ
*/
static void lis3lv02d_get_xyz(struct lis3lv02d *lis3, int *x, int *y, int *z)
{
int position[3];
position[0] = lis3->read_data(lis3, OUTX);
position[1] = lis3->read_data(lis3, OUTY);
position[2] = lis3->read_data(lis3, OUTZ);
*x = lis3lv02d_get_axis(lis3->ac.x, position);
*y = lis3lv02d_get_axis(lis3->ac.y, position);
*z = lis3lv02d_get_axis(lis3->ac.z, position);
}
void lis3lv02d_poweroff(struct lis3lv02d *lis3)
{
/* disable X,Y,Z axis and power down */
lis3->write(lis3, CTRL_REG1, 0x00);
}
EXPORT_SYMBOL_GPL(lis3lv02d_poweroff);
void lis3lv02d_poweron(struct lis3lv02d *lis3)
{
u8 reg;
lis3->init(lis3);
/*
* Common configuration
* BDU: LSB and MSB values are not updated until both have been read.
* So the value read will always be correct.
*/
lis3->read(lis3, CTRL_REG2, &reg);
reg |= CTRL2_BDU;
lis3->write(lis3, CTRL_REG2, reg);
}
EXPORT_SYMBOL_GPL(lis3lv02d_poweron);
static irqreturn_t lis302dl_interrupt(int irq, void *dummy)
{
/*
* Be careful: on some HP laptops the bios force DD when on battery and
* the lid is closed. This leads to interrupts as soon as a little move
* is done.
*/
atomic_inc(&lis3_dev.count);
wake_up_interruptible(&lis3_dev.misc_wait);
kill_fasync(&lis3_dev.async_queue, SIGIO, POLL_IN);
return IRQ_HANDLED;
}
static int lis3lv02d_misc_open(struct inode *inode, struct file *file)
{
int ret;
if (test_and_set_bit(0, &lis3_dev.misc_opened))
return -EBUSY; /* already open */
atomic_set(&lis3_dev.count, 0);
/*
* The sensor can generate interrupts for free-fall and direction
* detection (distinguishable with FF_WU_SRC and DD_SRC) but to keep
* the things simple and _fast_ we activate it only for free-fall, so
* no need to read register (very slow with ACPI). For the same reason,
* we forbid shared interrupts.
*
* IRQF_TRIGGER_RISING seems pointless on HP laptops because the
* io-apic is not configurable (and generates a warning) but I keep it
* in case of support for other hardware.
*/
ret = request_irq(lis3_dev.irq, lis302dl_interrupt, IRQF_TRIGGER_RISING,
DRIVER_NAME, &lis3_dev);
if (ret) {
clear_bit(0, &lis3_dev.misc_opened);
printk(KERN_ERR DRIVER_NAME ": IRQ%d allocation failed\n", lis3_dev.irq);
return -EBUSY;
}
return 0;
}
static int lis3lv02d_misc_release(struct inode *inode, struct file *file)
{
fasync_helper(-1, file, 0, &lis3_dev.async_queue);
free_irq(lis3_dev.irq, &lis3_dev);
clear_bit(0, &lis3_dev.misc_opened); /* release the device */
return 0;
}
static ssize_t lis3lv02d_misc_read(struct file *file, char __user *buf,
size_t count, loff_t *pos)
{
DECLARE_WAITQUEUE(wait, current);
u32 data;
unsigned char byte_data;
ssize_t retval = 1;
if (count < 1)
return -EINVAL;
add_wait_queue(&lis3_dev.misc_wait, &wait);
while (true) {
set_current_state(TASK_INTERRUPTIBLE);
data = atomic_xchg(&lis3_dev.count, 0);
if (data)
break;
if (file->f_flags & O_NONBLOCK) {
retval = -EAGAIN;
goto out;
}
if (signal_pending(current)) {
retval = -ERESTARTSYS;
goto out;
}
schedule();
}
if (data < 255)
byte_data = data;
else
byte_data = 255;
/* make sure we are not going into copy_to_user() with
* TASK_INTERRUPTIBLE state */
set_current_state(TASK_RUNNING);
if (copy_to_user(buf, &byte_data, sizeof(byte_data)))
retval = -EFAULT;
out:
__set_current_state(TASK_RUNNING);
remove_wait_queue(&lis3_dev.misc_wait, &wait);
return retval;
}
static unsigned int lis3lv02d_misc_poll(struct file *file, poll_table *wait)
{
poll_wait(file, &lis3_dev.misc_wait, wait);
if (atomic_read(&lis3_dev.count))
return POLLIN | POLLRDNORM;
return 0;
}
static int lis3lv02d_misc_fasync(int fd, struct file *file, int on)
{
return fasync_helper(fd, file, on, &lis3_dev.async_queue);
}
static const struct file_operations lis3lv02d_misc_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.read = lis3lv02d_misc_read,
.open = lis3lv02d_misc_open,
.release = lis3lv02d_misc_release,
.poll = lis3lv02d_misc_poll,
.fasync = lis3lv02d_misc_fasync,
};
static struct miscdevice lis3lv02d_misc_device = {
.minor = MISC_DYNAMIC_MINOR,
.name = "freefall",
.fops = &lis3lv02d_misc_fops,
};
static void lis3lv02d_joystick_poll(struct input_polled_dev *pidev)
{
int x, y, z;
lis3lv02d_get_xyz(&lis3_dev, &x, &y, &z);
input_report_abs(pidev->input, ABS_X, x - lis3_dev.xcalib);
input_report_abs(pidev->input, ABS_Y, y - lis3_dev.ycalib);
input_report_abs(pidev->input, ABS_Z, z - lis3_dev.zcalib);
}
static inline void lis3lv02d_calibrate_joystick(void)
{
lis3lv02d_get_xyz(&lis3_dev,
&lis3_dev.xcalib, &lis3_dev.ycalib, &lis3_dev.zcalib);
}
int lis3lv02d_joystick_enable(void)
{
struct input_dev *input_dev;
int err;
if (lis3_dev.idev)
return -EINVAL;
lis3_dev.idev = input_allocate_polled_device();
if (!lis3_dev.idev)
return -ENOMEM;
lis3_dev.idev->poll = lis3lv02d_joystick_poll;
lis3_dev.idev->poll_interval = MDPS_POLL_INTERVAL;
input_dev = lis3_dev.idev->input;
lis3lv02d_calibrate_joystick();
input_dev->name = "ST LIS3LV02DL Accelerometer";
input_dev->phys = DRIVER_NAME "/input0";
input_dev->id.bustype = BUS_HOST;
input_dev->id.vendor = 0;
input_dev->dev.parent = &lis3_dev.pdev->dev;
set_bit(EV_ABS, input_dev->evbit);
input_set_abs_params(input_dev, ABS_X, -lis3_dev.mdps_max_val, lis3_dev.mdps_max_val, 3, 3);
input_set_abs_params(input_dev, ABS_Y, -lis3_dev.mdps_max_val, lis3_dev.mdps_max_val, 3, 3);
input_set_abs_params(input_dev, ABS_Z, -lis3_dev.mdps_max_val, lis3_dev.mdps_max_val, 3, 3);
err = input_register_polled_device(lis3_dev.idev);
if (err) {
input_free_polled_device(lis3_dev.idev);
lis3_dev.idev = NULL;
}
return err;
}
EXPORT_SYMBOL_GPL(lis3lv02d_joystick_enable);
void lis3lv02d_joystick_disable(void)
{
if (!lis3_dev.idev)
return;
if (lis3_dev.irq)
misc_deregister(&lis3lv02d_misc_device);
input_unregister_polled_device(lis3_dev.idev);
lis3_dev.idev = NULL;
}
EXPORT_SYMBOL_GPL(lis3lv02d_joystick_disable);
/* Sysfs stuff */
static ssize_t lis3lv02d_position_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
int x, y, z;
lis3lv02d_get_xyz(&lis3_dev, &x, &y, &z);
return sprintf(buf, "(%d,%d,%d)\n", x, y, z);
}
static ssize_t lis3lv02d_calibrate_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "(%d,%d,%d)\n", lis3_dev.xcalib, lis3_dev.ycalib, lis3_dev.zcalib);
}
static ssize_t lis3lv02d_calibrate_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
lis3lv02d_calibrate_joystick();
return count;
}
/* conversion btw sampling rate and the register values */
static int lis3lv02dl_df_val[4] = {40, 160, 640, 2560};
static ssize_t lis3lv02d_rate_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
u8 ctrl;
int val;
lis3_dev.read(&lis3_dev, CTRL_REG1, &ctrl);
val = (ctrl & (CTRL1_DF0 | CTRL1_DF1)) >> 4;
return sprintf(buf, "%d\n", lis3lv02dl_df_val[val]);
}
static DEVICE_ATTR(position, S_IRUGO, lis3lv02d_position_show, NULL);
static DEVICE_ATTR(calibrate, S_IRUGO|S_IWUSR, lis3lv02d_calibrate_show,
lis3lv02d_calibrate_store);
static DEVICE_ATTR(rate, S_IRUGO, lis3lv02d_rate_show, NULL);
static struct attribute *lis3lv02d_attributes[] = {
&dev_attr_position.attr,
&dev_attr_calibrate.attr,
&dev_attr_rate.attr,
NULL
};
static struct attribute_group lis3lv02d_attribute_group = {
.attrs = lis3lv02d_attributes
};
static int lis3lv02d_add_fs(struct lis3lv02d *lis3)
{
lis3->pdev = platform_device_register_simple(DRIVER_NAME, -1, NULL, 0);
if (IS_ERR(lis3->pdev))
return PTR_ERR(lis3->pdev);
return sysfs_create_group(&lis3->pdev->dev.kobj, &lis3lv02d_attribute_group);
}
int lis3lv02d_remove_fs(struct lis3lv02d *lis3)
{
sysfs_remove_group(&lis3->pdev->dev.kobj, &lis3lv02d_attribute_group);
platform_device_unregister(lis3->pdev);
return 0;
}
EXPORT_SYMBOL_GPL(lis3lv02d_remove_fs);
/*
* Initialise the accelerometer and the various subsystems.
* Should be rather independant of the bus system.
*/
int lis3lv02d_init_device(struct lis3lv02d *dev)
{
dev->whoami = lis3lv02d_read_8(dev, WHO_AM_I);
switch (dev->whoami) {
case LIS_DOUBLE_ID:
printk(KERN_INFO DRIVER_NAME ": 2-byte sensor found\n");
dev->read_data = lis3lv02d_read_16;
dev->mdps_max_val = 2048;
break;
case LIS_SINGLE_ID:
printk(KERN_INFO DRIVER_NAME ": 1-byte sensor found\n");
dev->read_data = lis3lv02d_read_8;
dev->mdps_max_val = 128;
break;
default:
printk(KERN_ERR DRIVER_NAME
": unknown sensor type 0x%X\n", dev->whoami);
return -EINVAL;
}
lis3lv02d_add_fs(dev);
lis3lv02d_poweron(dev);
if (lis3lv02d_joystick_enable())
printk(KERN_ERR DRIVER_NAME ": joystick initialization failed\n");
/* passing in platform specific data is purely optional and only
* used by the SPI transport layer at the moment */
if (dev->pdata) {
struct lis3lv02d_platform_data *p = dev->pdata;
if (p->click_flags && (dev->whoami == LIS_SINGLE_ID)) {
dev->write(dev, CLICK_CFG, p->click_flags);
dev->write(dev, CLICK_TIMELIMIT, p->click_time_limit);
dev->write(dev, CLICK_LATENCY, p->click_latency);
dev->write(dev, CLICK_WINDOW, p->click_window);
dev->write(dev, CLICK_THSZ, p->click_thresh_z & 0xf);
dev->write(dev, CLICK_THSY_X,
(p->click_thresh_x & 0xf) |
(p->click_thresh_y << 4));
}
if (p->irq_cfg)
dev->write(dev, CTRL_REG3, p->irq_cfg);
}
/* bail if we did not get an IRQ from the bus layer */
if (!dev->irq) {
printk(KERN_ERR DRIVER_NAME
": No IRQ. Disabling /dev/freefall\n");
goto out;
}
if (misc_register(&lis3lv02d_misc_device))
printk(KERN_ERR DRIVER_NAME ": misc_register failed\n");
out:
return 0;
}
EXPORT_SYMBOL_GPL(lis3lv02d_init_device);
MODULE_DESCRIPTION("ST LIS3LV02Dx three-axis digital accelerometer driver");
MODULE_AUTHOR("Yan Burman, Eric Piel, Pavel Machek");
MODULE_LICENSE("GPL");
View Git Blame Copy Permalink