You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
277 lines
6.2 KiB
277 lines
6.2 KiB
/*
|
|
* Apple Motion Sensor driver (I2C variant)
|
|
*
|
|
* Copyright (C) 2005 Stelian Pop (stelian@popies.net)
|
|
* Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
|
|
*
|
|
* Clean room implementation based on the reverse engineered Mac OS X driver by
|
|
* Johannes Berg <johannes@sipsolutions.net>, documentation available at
|
|
* http://johannes.sipsolutions.net/PowerBook/Apple_Motion_Sensor_Specification
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/types.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/init.h>
|
|
#include <linux/delay.h>
|
|
|
|
#include "ams.h"
|
|
|
|
/* AMS registers */
|
|
#define AMS_COMMAND 0x00 /* command register */
|
|
#define AMS_STATUS 0x01 /* status register */
|
|
#define AMS_CTRL1 0x02 /* read control 1 (number of values) */
|
|
#define AMS_CTRL2 0x03 /* read control 2 (offset?) */
|
|
#define AMS_CTRL3 0x04 /* read control 3 (size of each value?) */
|
|
#define AMS_DATA1 0x05 /* read data 1 */
|
|
#define AMS_DATA2 0x06 /* read data 2 */
|
|
#define AMS_DATA3 0x07 /* read data 3 */
|
|
#define AMS_DATA4 0x08 /* read data 4 */
|
|
#define AMS_DATAX 0x20 /* data X */
|
|
#define AMS_DATAY 0x21 /* data Y */
|
|
#define AMS_DATAZ 0x22 /* data Z */
|
|
#define AMS_FREEFALL 0x24 /* freefall int control */
|
|
#define AMS_SHOCK 0x25 /* shock int control */
|
|
#define AMS_SENSLOW 0x26 /* sensitivity low limit */
|
|
#define AMS_SENSHIGH 0x27 /* sensitivity high limit */
|
|
#define AMS_CTRLX 0x28 /* control X */
|
|
#define AMS_CTRLY 0x29 /* control Y */
|
|
#define AMS_CTRLZ 0x2A /* control Z */
|
|
#define AMS_UNKNOWN1 0x2B /* unknown 1 */
|
|
#define AMS_UNKNOWN2 0x2C /* unknown 2 */
|
|
#define AMS_UNKNOWN3 0x2D /* unknown 3 */
|
|
#define AMS_VENDOR 0x2E /* vendor */
|
|
|
|
/* AMS commands - use with the AMS_COMMAND register */
|
|
enum ams_i2c_cmd {
|
|
AMS_CMD_NOOP = 0,
|
|
AMS_CMD_VERSION,
|
|
AMS_CMD_READMEM,
|
|
AMS_CMD_WRITEMEM,
|
|
AMS_CMD_ERASEMEM,
|
|
AMS_CMD_READEE,
|
|
AMS_CMD_WRITEEE,
|
|
AMS_CMD_RESET,
|
|
AMS_CMD_START,
|
|
};
|
|
|
|
static int ams_i2c_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id);
|
|
static int ams_i2c_remove(struct i2c_client *client);
|
|
|
|
static const struct i2c_device_id ams_id[] = {
|
|
{ "ams", 0 },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, ams_id);
|
|
|
|
static struct i2c_driver ams_i2c_driver = {
|
|
.driver = {
|
|
.name = "ams",
|
|
.owner = THIS_MODULE,
|
|
},
|
|
.probe = ams_i2c_probe,
|
|
.remove = ams_i2c_remove,
|
|
.id_table = ams_id,
|
|
};
|
|
|
|
static s32 ams_i2c_read(u8 reg)
|
|
{
|
|
return i2c_smbus_read_byte_data(ams_info.i2c_client, reg);
|
|
}
|
|
|
|
static int ams_i2c_write(u8 reg, u8 value)
|
|
{
|
|
return i2c_smbus_write_byte_data(ams_info.i2c_client, reg, value);
|
|
}
|
|
|
|
static int ams_i2c_cmd(enum ams_i2c_cmd cmd)
|
|
{
|
|
s32 result;
|
|
int count = 3;
|
|
|
|
ams_i2c_write(AMS_COMMAND, cmd);
|
|
msleep(5);
|
|
|
|
while (count--) {
|
|
result = ams_i2c_read(AMS_COMMAND);
|
|
if (result == 0 || result & 0x80)
|
|
return 0;
|
|
|
|
schedule_timeout_uninterruptible(HZ / 20);
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
static void ams_i2c_set_irq(enum ams_irq reg, char enable)
|
|
{
|
|
if (reg & AMS_IRQ_FREEFALL) {
|
|
u8 val = ams_i2c_read(AMS_CTRLX);
|
|
if (enable)
|
|
val |= 0x80;
|
|
else
|
|
val &= ~0x80;
|
|
ams_i2c_write(AMS_CTRLX, val);
|
|
}
|
|
|
|
if (reg & AMS_IRQ_SHOCK) {
|
|
u8 val = ams_i2c_read(AMS_CTRLY);
|
|
if (enable)
|
|
val |= 0x80;
|
|
else
|
|
val &= ~0x80;
|
|
ams_i2c_write(AMS_CTRLY, val);
|
|
}
|
|
|
|
if (reg & AMS_IRQ_GLOBAL) {
|
|
u8 val = ams_i2c_read(AMS_CTRLZ);
|
|
if (enable)
|
|
val |= 0x80;
|
|
else
|
|
val &= ~0x80;
|
|
ams_i2c_write(AMS_CTRLZ, val);
|
|
}
|
|
}
|
|
|
|
static void ams_i2c_clear_irq(enum ams_irq reg)
|
|
{
|
|
if (reg & AMS_IRQ_FREEFALL)
|
|
ams_i2c_write(AMS_FREEFALL, 0);
|
|
|
|
if (reg & AMS_IRQ_SHOCK)
|
|
ams_i2c_write(AMS_SHOCK, 0);
|
|
}
|
|
|
|
static u8 ams_i2c_get_vendor(void)
|
|
{
|
|
return ams_i2c_read(AMS_VENDOR);
|
|
}
|
|
|
|
static void ams_i2c_get_xyz(s8 *x, s8 *y, s8 *z)
|
|
{
|
|
*x = ams_i2c_read(AMS_DATAX);
|
|
*y = ams_i2c_read(AMS_DATAY);
|
|
*z = ams_i2c_read(AMS_DATAZ);
|
|
}
|
|
|
|
static int ams_i2c_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
int vmaj, vmin;
|
|
int result;
|
|
|
|
/* There can be only one */
|
|
if (unlikely(ams_info.has_device))
|
|
return -ENODEV;
|
|
|
|
ams_info.i2c_client = client;
|
|
|
|
if (ams_i2c_cmd(AMS_CMD_RESET)) {
|
|
printk(KERN_INFO "ams: Failed to reset the device\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
if (ams_i2c_cmd(AMS_CMD_START)) {
|
|
printk(KERN_INFO "ams: Failed to start the device\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
/* get version/vendor information */
|
|
ams_i2c_write(AMS_CTRL1, 0x02);
|
|
ams_i2c_write(AMS_CTRL2, 0x85);
|
|
ams_i2c_write(AMS_CTRL3, 0x01);
|
|
|
|
ams_i2c_cmd(AMS_CMD_READMEM);
|
|
|
|
vmaj = ams_i2c_read(AMS_DATA1);
|
|
vmin = ams_i2c_read(AMS_DATA2);
|
|
if (vmaj != 1 || vmin != 52) {
|
|
printk(KERN_INFO "ams: Incorrect device version (%d.%d)\n",
|
|
vmaj, vmin);
|
|
return -ENODEV;
|
|
}
|
|
|
|
ams_i2c_cmd(AMS_CMD_VERSION);
|
|
|
|
vmaj = ams_i2c_read(AMS_DATA1);
|
|
vmin = ams_i2c_read(AMS_DATA2);
|
|
if (vmaj != 0 || vmin != 1) {
|
|
printk(KERN_INFO "ams: Incorrect firmware version (%d.%d)\n",
|
|
vmaj, vmin);
|
|
return -ENODEV;
|
|
}
|
|
|
|
/* Disable interrupts */
|
|
ams_i2c_set_irq(AMS_IRQ_ALL, 0);
|
|
|
|
result = ams_sensor_attach();
|
|
if (result < 0)
|
|
return result;
|
|
|
|
/* Set default values */
|
|
ams_i2c_write(AMS_SENSLOW, 0x15);
|
|
ams_i2c_write(AMS_SENSHIGH, 0x60);
|
|
ams_i2c_write(AMS_CTRLX, 0x08);
|
|
ams_i2c_write(AMS_CTRLY, 0x0F);
|
|
ams_i2c_write(AMS_CTRLZ, 0x4F);
|
|
ams_i2c_write(AMS_UNKNOWN1, 0x14);
|
|
|
|
/* Clear interrupts */
|
|
ams_i2c_clear_irq(AMS_IRQ_ALL);
|
|
|
|
ams_info.has_device = 1;
|
|
|
|
/* Enable interrupts */
|
|
ams_i2c_set_irq(AMS_IRQ_ALL, 1);
|
|
|
|
printk(KERN_INFO "ams: Found I2C based motion sensor\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ams_i2c_remove(struct i2c_client *client)
|
|
{
|
|
if (ams_info.has_device) {
|
|
ams_sensor_detach();
|
|
|
|
/* Disable interrupts */
|
|
ams_i2c_set_irq(AMS_IRQ_ALL, 0);
|
|
|
|
/* Clear interrupts */
|
|
ams_i2c_clear_irq(AMS_IRQ_ALL);
|
|
|
|
printk(KERN_INFO "ams: Unloading\n");
|
|
|
|
ams_info.has_device = 0;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void ams_i2c_exit(void)
|
|
{
|
|
i2c_del_driver(&ams_i2c_driver);
|
|
}
|
|
|
|
int __init ams_i2c_init(struct device_node *np)
|
|
{
|
|
int result;
|
|
|
|
/* Set implementation stuff */
|
|
ams_info.of_node = np;
|
|
ams_info.exit = ams_i2c_exit;
|
|
ams_info.get_vendor = ams_i2c_get_vendor;
|
|
ams_info.get_xyz = ams_i2c_get_xyz;
|
|
ams_info.clear_irq = ams_i2c_clear_irq;
|
|
ams_info.bustype = BUS_I2C;
|
|
|
|
result = i2c_add_driver(&ams_i2c_driver);
|
|
|
|
return result;
|
|
}
|
|
|