/drivers/staging/iio/accel/sca3000_core.c
C | 1272 lines | 968 code | 130 blank | 174 comment | 119 complexity | 05581f1ae65d1ff83c446e689079ab58 MD5 | raw file
Possible License(s): GPL-2.0, LGPL-2.0, AGPL-1.0
/*
* sca3000_core.c -- support VTI sca3000 series accelerometers via SPI
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*
* Copyright (c) 2009 Jonathan Cameron <jic23@cam.ac.uk>
*
* See industrialio/accels/sca3000.h for comments.
*/
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <linux/fs.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/spi/spi.h>
#include <linux/sysfs.h>
#include "../iio.h"
#include "../sysfs.h"
#include "../ring_generic.h"
#include "accel.h"
#include "sca3000.h"
enum sca3000_variant {
d01,
e02,
e04,
e05,
};
/* Note where option modes are not defined, the chip simply does not
* support any.
* Other chips in the sca3000 series use i2c and are not included here.
*
* Some of these devices are only listed in the family data sheet and
* do not actually appear to be available.
*/
static const struct sca3000_chip_info sca3000_spi_chip_info_tbl[] = {
[d01] = {
.scale = 7357,
.temp_output = true,
.measurement_mode_freq = 250,
.option_mode_1 = SCA3000_OP_MODE_BYPASS,
.option_mode_1_freq = 250,
.mot_det_mult_xz = {50, 100, 200, 350, 650, 1300},
.mot_det_mult_y = {50, 100, 150, 250, 450, 850, 1750},
},
[e02] = {
.scale = 9810,
.measurement_mode_freq = 125,
.option_mode_1 = SCA3000_OP_MODE_NARROW,
.option_mode_1_freq = 63,
.mot_det_mult_xz = {100, 150, 300, 550, 1050, 2050},
.mot_det_mult_y = {50, 100, 200, 350, 700, 1350, 2700},
},
[e04] = {
.scale = 19620,
.measurement_mode_freq = 100,
.option_mode_1 = SCA3000_OP_MODE_NARROW,
.option_mode_1_freq = 50,
.option_mode_2 = SCA3000_OP_MODE_WIDE,
.option_mode_2_freq = 400,
.mot_det_mult_xz = {200, 300, 600, 1100, 2100, 4100},
.mot_det_mult_y = {100, 200, 400, 7000, 1400, 2700, 54000},
},
[e05] = {
.scale = 61313,
.measurement_mode_freq = 200,
.option_mode_1 = SCA3000_OP_MODE_NARROW,
.option_mode_1_freq = 50,
.option_mode_2 = SCA3000_OP_MODE_WIDE,
.option_mode_2_freq = 400,
.mot_det_mult_xz = {600, 900, 1700, 3200, 6100, 11900},
.mot_det_mult_y = {300, 600, 1200, 2000, 4100, 7800, 15600},
},
};
int sca3000_write_reg(struct sca3000_state *st, u8 address, u8 val)
{
st->tx[0] = SCA3000_WRITE_REG(address);
st->tx[1] = val;
return spi_write(st->us, st->tx, 2);
}
int sca3000_read_data_short(struct sca3000_state *st,
uint8_t reg_address_high,
int len)
{
struct spi_message msg;
struct spi_transfer xfer[2] = {
{
.len = 1,
.tx_buf = st->tx,
}, {
.len = len,
.rx_buf = st->rx,
}
};
st->tx[0] = SCA3000_READ_REG(reg_address_high);
spi_message_init(&msg);
spi_message_add_tail(&xfer[0], &msg);
spi_message_add_tail(&xfer[1], &msg);
return spi_sync(st->us, &msg);
}
/**
* sca3000_reg_lock_on() test if the ctrl register lock is on
*
* Lock must be held.
**/
static int sca3000_reg_lock_on(struct sca3000_state *st)
{
int ret;
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_STATUS, 1);
if (ret < 0)
return ret;
return !(st->rx[0] & SCA3000_LOCKED);
}
/**
* __sca3000_unlock_reg_lock() unlock the control registers
*
* Note the device does not appear to support doing this in a single transfer.
* This should only ever be used as part of ctrl reg read.
* Lock must be held before calling this
**/
static int __sca3000_unlock_reg_lock(struct sca3000_state *st)
{
struct spi_message msg;
struct spi_transfer xfer[3] = {
{
.len = 2,
.cs_change = 1,
.tx_buf = st->tx,
}, {
.len = 2,
.cs_change = 1,
.tx_buf = st->tx + 2,
}, {
.len = 2,
.tx_buf = st->tx + 4,
},
};
st->tx[0] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK);
st->tx[1] = 0x00;
st->tx[2] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK);
st->tx[3] = 0x50;
st->tx[4] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK);
st->tx[5] = 0xA0;
spi_message_init(&msg);
spi_message_add_tail(&xfer[0], &msg);
spi_message_add_tail(&xfer[1], &msg);
spi_message_add_tail(&xfer[2], &msg);
return spi_sync(st->us, &msg);
}
/**
* sca3000_write_ctrl_reg() write to a lock protect ctrl register
* @sel: selects which registers we wish to write to
* @val: the value to be written
*
* Certain control registers are protected against overwriting by the lock
* register and use a shared write address. This function allows writing of
* these registers.
* Lock must be held.
**/
static int sca3000_write_ctrl_reg(struct sca3000_state *st,
uint8_t sel,
uint8_t val)
{
int ret;
ret = sca3000_reg_lock_on(st);
if (ret < 0)
goto error_ret;
if (ret) {
ret = __sca3000_unlock_reg_lock(st);
if (ret)
goto error_ret;
}
/* Set the control select register */
ret = sca3000_write_reg(st, SCA3000_REG_ADDR_CTRL_SEL, sel);
if (ret)
goto error_ret;
/* Write the actual value into the register */
ret = sca3000_write_reg(st, SCA3000_REG_ADDR_CTRL_DATA, val);
error_ret:
return ret;
}
/* Crucial that lock is called before calling this */
/**
* sca3000_read_ctrl_reg() read from lock protected control register.
*
* Lock must be held.
**/
static int sca3000_read_ctrl_reg(struct sca3000_state *st,
u8 ctrl_reg)
{
int ret;
ret = sca3000_reg_lock_on(st);
if (ret < 0)
goto error_ret;
if (ret) {
ret = __sca3000_unlock_reg_lock(st);
if (ret)
goto error_ret;
}
/* Set the control select register */
ret = sca3000_write_reg(st, SCA3000_REG_ADDR_CTRL_SEL, ctrl_reg);
if (ret)
goto error_ret;
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_CTRL_DATA, 1);
if (ret)
goto error_ret;
else
return st->rx[0];
error_ret:
return ret;
}
#ifdef SCA3000_DEBUG
/**
* sca3000_check_status() check the status register
*
* Only used for debugging purposes
**/
static int sca3000_check_status(struct device *dev)
{
int ret;
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct sca3000_state *st = indio_dev->dev_data;
mutex_lock(&st->lock);
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_STATUS, 1);
if (ret < 0)
goto error_ret;
if (st->rx[0] & SCA3000_EEPROM_CS_ERROR)
dev_err(dev, "eeprom error\n");
if (st->rx[0] & SCA3000_SPI_FRAME_ERROR)
dev_err(dev, "Previous SPI Frame was corrupt\n");
error_ret:
mutex_unlock(&st->lock);
return ret;
}
#endif /* SCA3000_DEBUG */
/**
* sca3000_show_reg() - sysfs interface to read the chip revision number
**/
static ssize_t sca3000_show_rev(struct device *dev,
struct device_attribute *attr,
char *buf)
{
int len = 0, ret;
struct iio_dev *dev_info = dev_get_drvdata(dev);
struct sca3000_state *st = dev_info->dev_data;
mutex_lock(&st->lock);
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_REVID, 1);
if (ret < 0)
goto error_ret;
len += sprintf(buf + len,
"major=%d, minor=%d\n",
st->rx[0] & SCA3000_REVID_MAJOR_MASK,
st->rx[0] & SCA3000_REVID_MINOR_MASK);
error_ret:
mutex_unlock(&st->lock);
return ret ? ret : len;
}
/**
* sca3000_show_available_measurement_modes() display available modes
*
* This is all read from chip specific data in the driver. Not all
* of the sca3000 series support modes other than normal.
**/
static ssize_t
sca3000_show_available_measurement_modes(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *dev_info = dev_get_drvdata(dev);
struct sca3000_state *st = dev_info->dev_data;
int len = 0;
len += sprintf(buf + len, "0 - normal mode");
switch (st->info->option_mode_1) {
case SCA3000_OP_MODE_NARROW:
len += sprintf(buf + len, ", 1 - narrow mode");
break;
case SCA3000_OP_MODE_BYPASS:
len += sprintf(buf + len, ", 1 - bypass mode");
break;
}
switch (st->info->option_mode_2) {
case SCA3000_OP_MODE_WIDE:
len += sprintf(buf + len, ", 2 - wide mode");
break;
}
/* always supported */
len += sprintf(buf + len, " 3 - motion detection\n");
return len;
}
/**
* sca3000_show_measurmenet_mode() sysfs read of current mode
**/
static ssize_t
sca3000_show_measurement_mode(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *dev_info = dev_get_drvdata(dev);
struct sca3000_state *st = dev_info->dev_data;
int len = 0, ret;
mutex_lock(&st->lock);
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
if (ret)
goto error_ret;
/* mask bottom 2 bits - only ones that are relevant */
st->rx[0] &= 0x03;
switch (st->rx[0]) {
case SCA3000_MEAS_MODE_NORMAL:
len += sprintf(buf + len, "0 - normal mode\n");
break;
case SCA3000_MEAS_MODE_MOT_DET:
len += sprintf(buf + len, "3 - motion detection\n");
break;
case SCA3000_MEAS_MODE_OP_1:
switch (st->info->option_mode_1) {
case SCA3000_OP_MODE_NARROW:
len += sprintf(buf + len, "1 - narrow mode\n");
break;
case SCA3000_OP_MODE_BYPASS:
len += sprintf(buf + len, "1 - bypass mode\n");
break;
}
break;
case SCA3000_MEAS_MODE_OP_2:
switch (st->info->option_mode_2) {
case SCA3000_OP_MODE_WIDE:
len += sprintf(buf + len, "2 - wide mode\n");
break;
}
break;
}
error_ret:
mutex_unlock(&st->lock);
return ret ? ret : len;
}
/**
* sca3000_store_measurement_mode() set the current mode
**/
static ssize_t
sca3000_store_measurement_mode(struct device *dev,
struct device_attribute *attr,
const char *buf,
size_t len)
{
struct iio_dev *dev_info = dev_get_drvdata(dev);
struct sca3000_state *st = dev_info->dev_data;
int ret;
int mask = 0x03;
long val;
mutex_lock(&st->lock);
ret = strict_strtol(buf, 10, &val);
if (ret)
goto error_ret;
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
if (ret)
goto error_ret;
st->rx[0] &= ~mask;
st->rx[0] |= (val & mask);
ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE, st->rx[0]);
if (ret)
goto error_ret;
mutex_unlock(&st->lock);
return len;
error_ret:
mutex_unlock(&st->lock);
return ret;
}
/* Not even vaguely standard attributes so defined here rather than
* in the relevant IIO core headers
*/
static IIO_DEVICE_ATTR(measurement_mode_available, S_IRUGO,
sca3000_show_available_measurement_modes,
NULL, 0);
static IIO_DEVICE_ATTR(measurement_mode, S_IRUGO | S_IWUSR,
sca3000_show_measurement_mode,
sca3000_store_measurement_mode,
0);
/* More standard attributes */
static IIO_DEV_ATTR_REV(sca3000_show_rev);
#define SCA3000_INFO_MASK \
(1 << IIO_CHAN_INFO_SCALE_SHARED)
#define SCA3000_EVENT_MASK \
(IIO_EV_BIT(IIO_EV_TYPE_MAG, IIO_EV_DIR_RISING))
static struct iio_chan_spec sca3000_channels[] = {
IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_X, SCA3000_INFO_MASK,
0, 0, IIO_ST('s', 11, 16, 5), SCA3000_EVENT_MASK),
IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_Y, SCA3000_INFO_MASK,
1, 1, IIO_ST('s', 11, 16, 5), SCA3000_EVENT_MASK),
IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_Z, SCA3000_INFO_MASK,
2, 2, IIO_ST('s', 11, 16, 5), SCA3000_EVENT_MASK),
};
static u8 sca3000_addresses[3][3] = {
[0] = {SCA3000_REG_ADDR_X_MSB, SCA3000_REG_CTRL_SEL_MD_X_TH,
SCA3000_MD_CTRL_OR_X},
[1] = {SCA3000_REG_ADDR_Y_MSB, SCA3000_REG_CTRL_SEL_MD_Y_TH,
SCA3000_MD_CTRL_OR_Y},
[2] = {SCA3000_REG_ADDR_Z_MSB, SCA3000_REG_CTRL_SEL_MD_Z_TH,
SCA3000_MD_CTRL_OR_Z},
};
static int sca3000_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val,
int *val2,
long mask)
{
struct sca3000_state *st = indio_dev->dev_data;
int ret;
u8 address;
switch (mask) {
case 0:
mutex_lock(&st->lock);
if (st->mo_det_use_count) {
mutex_unlock(&st->lock);
return -EBUSY;
}
address = sca3000_addresses[chan->address][0];
ret = sca3000_read_data_short(st, address, 2);
if (ret < 0) {
mutex_unlock(&st->lock);
return ret;
}
*val = (be16_to_cpup((__be16 *)st->rx) >> 3) & 0x1FFF;
*val = ((*val) << (sizeof(*val)*8 - 13)) >>
(sizeof(*val)*8 - 13);
mutex_unlock(&st->lock);
return IIO_VAL_INT;
case (1 << IIO_CHAN_INFO_SCALE_SHARED):
*val = 0;
if (chan->type == IIO_ACCEL)
*val2 = st->info->scale;
else /* temperature */
*val2 = 555556;
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
/**
* sca3000_read_av_freq() sysfs function to get available frequencies
*
* The later modes are only relevant to the ring buffer - and depend on current
* mode. Note that data sheet gives rather wide tolerances for these so integer
* division will give good enough answer and not all chips have them specified
* at all.
**/
static ssize_t sca3000_read_av_freq(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct sca3000_state *st = indio_dev->dev_data;
int len = 0, ret, val;
mutex_lock(&st->lock);
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
val = st->rx[0];
mutex_unlock(&st->lock);
if (ret)
goto error_ret;
switch (val & 0x03) {
case SCA3000_MEAS_MODE_NORMAL:
len += sprintf(buf + len, "%d %d %d\n",
st->info->measurement_mode_freq,
st->info->measurement_mode_freq/2,
st->info->measurement_mode_freq/4);
break;
case SCA3000_MEAS_MODE_OP_1:
len += sprintf(buf + len, "%d %d %d\n",
st->info->option_mode_1_freq,
st->info->option_mode_1_freq/2,
st->info->option_mode_1_freq/4);
break;
case SCA3000_MEAS_MODE_OP_2:
len += sprintf(buf + len, "%d %d %d\n",
st->info->option_mode_2_freq,
st->info->option_mode_2_freq/2,
st->info->option_mode_2_freq/4);
break;
}
return len;
error_ret:
return ret;
}
/**
* __sca3000_get_base_frequency() obtain mode specific base frequency
*
* lock must be held
**/
static inline int __sca3000_get_base_freq(struct sca3000_state *st,
const struct sca3000_chip_info *info,
int *base_freq)
{
int ret;
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
if (ret)
goto error_ret;
switch (0x03 & st->rx[0]) {
case SCA3000_MEAS_MODE_NORMAL:
*base_freq = info->measurement_mode_freq;
break;
case SCA3000_MEAS_MODE_OP_1:
*base_freq = info->option_mode_1_freq;
break;
case SCA3000_MEAS_MODE_OP_2:
*base_freq = info->option_mode_2_freq;
break;
}
error_ret:
return ret;
}
/**
* sca3000_read_frequency() sysfs interface to get the current frequency
**/
static ssize_t sca3000_read_frequency(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct sca3000_state *st = indio_dev->dev_data;
int ret, len = 0, base_freq = 0, val;
mutex_lock(&st->lock);
ret = __sca3000_get_base_freq(st, st->info, &base_freq);
if (ret)
goto error_ret_mut;
ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL);
mutex_unlock(&st->lock);
if (ret)
goto error_ret;
val = ret;
if (base_freq > 0)
switch (val & 0x03) {
case 0x00:
case 0x03:
len = sprintf(buf, "%d\n", base_freq);
break;
case 0x01:
len = sprintf(buf, "%d\n", base_freq/2);
break;
case 0x02:
len = sprintf(buf, "%d\n", base_freq/4);
break;
}
return len;
error_ret_mut:
mutex_unlock(&st->lock);
error_ret:
return ret;
}
/**
* sca3000_set_frequency() sysfs interface to set the current frequency
**/
static ssize_t sca3000_set_frequency(struct device *dev,
struct device_attribute *attr,
const char *buf,
size_t len)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct sca3000_state *st = indio_dev->dev_data;
int ret, base_freq = 0;
int ctrlval;
long val;
ret = strict_strtol(buf, 10, &val);
if (ret)
return ret;
mutex_lock(&st->lock);
/* What mode are we in? */
ret = __sca3000_get_base_freq(st, st->info, &base_freq);
if (ret)
goto error_free_lock;
ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL);
if (ret < 0)
goto error_free_lock;
ctrlval = ret;
/* clear the bits */
ctrlval &= ~0x03;
if (val == base_freq/2) {
ctrlval |= SCA3000_OUT_CTRL_BUF_DIV_2;
} else if (val == base_freq/4) {
ctrlval |= SCA3000_OUT_CTRL_BUF_DIV_4;
} else if (val != base_freq) {
ret = -EINVAL;
goto error_free_lock;
}
ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL,
ctrlval);
error_free_lock:
mutex_unlock(&st->lock);
return ret ? ret : len;
}
/* Should only really be registered if ring buffer support is compiled in.
* Does no harm however and doing it right would add a fair bit of complexity
*/
static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(sca3000_read_av_freq);
static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
sca3000_read_frequency,
sca3000_set_frequency);
/**
* sca3000_read_temp() sysfs interface to get the temperature when available
*
* The alignment of data in here is downright odd. See data sheet.
* Converting this into a meaningful value is left to inline functions in
* userspace part of header.
**/
static ssize_t sca3000_read_temp(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct sca3000_state *st = indio_dev->dev_data;
int ret;
int val;
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_TEMP_MSB, 2);
if (ret < 0)
goto error_ret;
val = ((st->rx[0] & 0x3F) << 3) | ((st->rx[1] & 0xE0) >> 5);
return sprintf(buf, "%d\n", val);
error_ret:
return ret;
}
static IIO_DEV_ATTR_TEMP_RAW(sca3000_read_temp);
static IIO_CONST_ATTR_TEMP_SCALE("0.555556");
static IIO_CONST_ATTR_TEMP_OFFSET("-214.6");
/**
* sca3000_read_thresh() - query of a threshold
**/
static int sca3000_read_thresh(struct iio_dev *indio_dev,
int e,
int *val)
{
int ret, i;
struct sca3000_state *st = indio_dev->dev_data;
int num = IIO_EVENT_CODE_EXTRACT_MODIFIER(e);
mutex_lock(&st->lock);
ret = sca3000_read_ctrl_reg(st, sca3000_addresses[num][1]);
mutex_unlock(&st->lock);
if (ret < 0)
return ret;
*val = 0;
if (num == 1)
for_each_set_bit(i, (unsigned long *)&ret,
ARRAY_SIZE(st->info->mot_det_mult_y))
*val += st->info->mot_det_mult_y[i];
else
for_each_set_bit(i, (unsigned long *)&ret,
ARRAY_SIZE(st->info->mot_det_mult_xz))
*val += st->info->mot_det_mult_xz[i];
return 0;
}
/**
* sca3000_write_thresh() control of threshold
**/
static int sca3000_write_thresh(struct iio_dev *indio_dev,
int e,
int val)
{
struct sca3000_state *st = indio_dev->dev_data;
int num = IIO_EVENT_CODE_EXTRACT_MODIFIER(e);
int ret;
int i;
u8 nonlinear = 0;
if (num == 1) {
i = ARRAY_SIZE(st->info->mot_det_mult_y);
while (i > 0)
if (val >= st->info->mot_det_mult_y[--i]) {
nonlinear |= (1 << i);
val -= st->info->mot_det_mult_y[i];
}
} else {
i = ARRAY_SIZE(st->info->mot_det_mult_xz);
while (i > 0)
if (val >= st->info->mot_det_mult_xz[--i]) {
nonlinear |= (1 << i);
val -= st->info->mot_det_mult_xz[i];
}
}
mutex_lock(&st->lock);
ret = sca3000_write_ctrl_reg(st, sca3000_addresses[num][1], nonlinear);
mutex_unlock(&st->lock);
return ret;
}
static struct attribute *sca3000_attributes[] = {
&iio_dev_attr_revision.dev_attr.attr,
&iio_dev_attr_measurement_mode_available.dev_attr.attr,
&iio_dev_attr_measurement_mode.dev_attr.attr,
&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
&iio_dev_attr_sampling_frequency.dev_attr.attr,
NULL,
};
static struct attribute *sca3000_attributes_with_temp[] = {
&iio_dev_attr_revision.dev_attr.attr,
&iio_dev_attr_measurement_mode_available.dev_attr.attr,
&iio_dev_attr_measurement_mode.dev_attr.attr,
&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
&iio_dev_attr_sampling_frequency.dev_attr.attr,
/* Only present if temp sensor is */
&iio_dev_attr_temp_raw.dev_attr.attr,
&iio_const_attr_temp_offset.dev_attr.attr,
&iio_const_attr_temp_scale.dev_attr.attr,
NULL,
};
static const struct attribute_group sca3000_attribute_group = {
.attrs = sca3000_attributes,
};
static const struct attribute_group sca3000_attribute_group_with_temp = {
.attrs = sca3000_attributes_with_temp,
};
/* RING RELATED interrupt handler */
/* depending on event, push to the ring buffer event chrdev or the event one */
/**
* sca3000_event_handler() - handling ring and non ring events
*
* This function is complicated by the fact that the devices can signify ring
* and non ring events via the same interrupt line and they can only
* be distinguished via a read of the relevant status register.
**/
static irqreturn_t sca3000_event_handler(int irq, void *private)
{
struct iio_dev *indio_dev = private;
struct sca3000_state *st;
int ret, val;
s64 last_timestamp = iio_get_time_ns();
st = indio_dev->dev_data;
/* Could lead if badly timed to an extra read of status reg,
* but ensures no interrupt is missed.
*/
mutex_lock(&st->lock);
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_STATUS, 1);
val = st->rx[0];
mutex_unlock(&st->lock);
if (ret)
goto done;
sca3000_ring_int_process(val, st->indio_dev->ring);
if (val & SCA3000_INT_STATUS_FREE_FALL)
iio_push_event(st->indio_dev, 0,
IIO_MOD_EVENT_CODE(IIO_EV_CLASS_ACCEL,
0,
IIO_EV_MOD_X_AND_Y_AND_Z,
IIO_EV_TYPE_MAG,
IIO_EV_DIR_FALLING),
last_timestamp);
if (val & SCA3000_INT_STATUS_Y_TRIGGER)
iio_push_event(st->indio_dev, 0,
IIO_MOD_EVENT_CODE(IIO_EV_CLASS_ACCEL,
0,
IIO_EV_MOD_Y,
IIO_EV_TYPE_MAG,
IIO_EV_DIR_RISING),
last_timestamp);
if (val & SCA3000_INT_STATUS_X_TRIGGER)
iio_push_event(st->indio_dev, 0,
IIO_MOD_EVENT_CODE(IIO_EV_CLASS_ACCEL,
0,
IIO_EV_MOD_X,
IIO_EV_TYPE_MAG,
IIO_EV_DIR_RISING),
last_timestamp);
if (val & SCA3000_INT_STATUS_Z_TRIGGER)
iio_push_event(st->indio_dev, 0,
IIO_MOD_EVENT_CODE(IIO_EV_CLASS_ACCEL,
0,
IIO_EV_MOD_Z,
IIO_EV_TYPE_MAG,
IIO_EV_DIR_RISING),
last_timestamp);
done:
return IRQ_HANDLED;
}
/**
* sca3000_read_event_config() what events are enabled
**/
static int sca3000_read_event_config(struct iio_dev *indio_dev,
int e)
{
struct sca3000_state *st = indio_dev->dev_data;
int ret;
u8 protect_mask = 0x03;
int num = IIO_EVENT_CODE_EXTRACT_MODIFIER(e);
/* read current value of mode register */
mutex_lock(&st->lock);
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
if (ret)
goto error_ret;
if ((st->rx[0] & protect_mask) != SCA3000_MEAS_MODE_MOT_DET)
ret = 0;
else {
ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL);
if (ret < 0)
goto error_ret;
/* only supporting logical or's for now */
ret = !!(ret & sca3000_addresses[num][2]);
}
error_ret:
mutex_unlock(&st->lock);
return ret;
}
/**
* sca3000_query_free_fall_mode() is free fall mode enabled
**/
static ssize_t sca3000_query_free_fall_mode(struct device *dev,
struct device_attribute *attr,
char *buf)
{
int ret, len;
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct sca3000_state *st = indio_dev->dev_data;
int val;
mutex_lock(&st->lock);
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
val = st->rx[0];
mutex_unlock(&st->lock);
if (ret < 0)
return ret;
len = sprintf(buf, "%d\n",
!!(val & SCA3000_FREE_FALL_DETECT));
return len;
}
/**
* sca3000_set_free_fall_mode() simple on off control for free fall int
*
* In these chips the free fall detector should send an interrupt if
* the device falls more than 25cm. This has not been tested due
* to fragile wiring.
**/
static ssize_t sca3000_set_free_fall_mode(struct device *dev,
struct device_attribute *attr,
const char *buf,
size_t len)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct sca3000_state *st = indio_dev->dev_data;
long val;
int ret;
u8 protect_mask = SCA3000_FREE_FALL_DETECT;
mutex_lock(&st->lock);
ret = strict_strtol(buf, 10, &val);
if (ret)
goto error_ret;
/* read current value of mode register */
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
if (ret)
goto error_ret;
/*if off and should be on*/
if (val && !(st->rx[0] & protect_mask))
ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
(st->rx[0] | SCA3000_FREE_FALL_DETECT));
/* if on and should be off */
else if (!val && (st->rx[0] & protect_mask))
ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
(st->rx[0] & ~protect_mask));
error_ret:
mutex_unlock(&st->lock);
return ret ? ret : len;
}
/**
* sca3000_set_mo_det() simple on off control for motion detector
*
* This is a per axis control, but enabling any will result in the
* motion detector unit being enabled.
* N.B. enabling motion detector stops normal data acquisition.
* There is a complexity in knowing which mode to return to when
* this mode is disabled. Currently normal mode is assumed.
**/
static int sca3000_write_event_config(struct iio_dev *indio_dev,
int e,
int state)
{
struct sca3000_state *st = indio_dev->dev_data;
int ret, ctrlval;
u8 protect_mask = 0x03;
int num = IIO_EVENT_CODE_EXTRACT_MODIFIER(e);
mutex_lock(&st->lock);
/* First read the motion detector config to find out if
* this axis is on*/
ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL);
if (ret < 0)
goto exit_point;
ctrlval = ret;
/* Off and should be on */
if (state && !(ctrlval & sca3000_addresses[num][2])) {
ret = sca3000_write_ctrl_reg(st,
SCA3000_REG_CTRL_SEL_MD_CTRL,
ctrlval |
sca3000_addresses[num][2]);
if (ret)
goto exit_point;
st->mo_det_use_count++;
} else if (!state && (ctrlval & sca3000_addresses[num][2])) {
ret = sca3000_write_ctrl_reg(st,
SCA3000_REG_CTRL_SEL_MD_CTRL,
ctrlval &
~(sca3000_addresses[num][2]));
if (ret)
goto exit_point;
st->mo_det_use_count--;
}
/* read current value of mode register */
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
if (ret)
goto exit_point;
/*if off and should be on*/
if ((st->mo_det_use_count)
&& ((st->rx[0] & protect_mask) != SCA3000_MEAS_MODE_MOT_DET))
ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
(st->rx[0] & ~protect_mask)
| SCA3000_MEAS_MODE_MOT_DET);
/* if on and should be off */
else if (!(st->mo_det_use_count)
&& ((st->rx[0] & protect_mask) == SCA3000_MEAS_MODE_MOT_DET))
ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
(st->rx[0] & ~protect_mask));
exit_point:
mutex_unlock(&st->lock);
return ret;
}
/* Free fall detector related event attribute */
static IIO_DEVICE_ATTR_NAMED(accel_xayaz_mag_falling_en,
accel_x&y&z_mag_falling_en,
S_IRUGO | S_IWUSR,
sca3000_query_free_fall_mode,
sca3000_set_free_fall_mode,
0);
static IIO_CONST_ATTR_NAMED(accel_xayaz_mag_falling_period,
accel_x&y&z_mag_falling_period,
"0.226");
static struct attribute *sca3000_event_attributes[] = {
&iio_dev_attr_accel_xayaz_mag_falling_en.dev_attr.attr,
&iio_const_attr_accel_xayaz_mag_falling_period.dev_attr.attr,
NULL,
};
static struct attribute_group sca3000_event_attribute_group = {
.attrs = sca3000_event_attributes,
};
/**
* sca3000_clean_setup() get the device into a predictable state
*
* Devices use flash memory to store many of the register values
* and hence can come up in somewhat unpredictable states.
* Hence reset everything on driver load.
**/
static int sca3000_clean_setup(struct sca3000_state *st)
{
int ret;
mutex_lock(&st->lock);
/* Ensure all interrupts have been acknowledged */
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_STATUS, 1);
if (ret)
goto error_ret;
/* Turn off all motion detection channels */
ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL);
if (ret < 0)
goto error_ret;
ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL,
ret & SCA3000_MD_CTRL_PROT_MASK);
if (ret)
goto error_ret;
/* Disable ring buffer */
ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL);
ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL,
(ret & SCA3000_OUT_CTRL_PROT_MASK)
| SCA3000_OUT_CTRL_BUF_X_EN
| SCA3000_OUT_CTRL_BUF_Y_EN
| SCA3000_OUT_CTRL_BUF_Z_EN
| SCA3000_OUT_CTRL_BUF_DIV_4);
if (ret)
goto error_ret;
/* Enable interrupts, relevant to mode and set up as active low */
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_MASK, 1);
if (ret)
goto error_ret;
ret = sca3000_write_reg(st,
SCA3000_REG_ADDR_INT_MASK,
(ret & SCA3000_INT_MASK_PROT_MASK)
| SCA3000_INT_MASK_ACTIVE_LOW);
if (ret)
goto error_ret;
/* Select normal measurement mode, free fall off, ring off */
/* Ring in 12 bit mode - it is fine to overwrite reserved bits 3,5
* as that occurs in one of the example on the datasheet */
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
if (ret)
goto error_ret;
ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
(st->rx[0] & SCA3000_MODE_PROT_MASK));
st->bpse = 11;
error_ret:
mutex_unlock(&st->lock);
return ret;
}
static const struct iio_info sca3000_info = {
.attrs = &sca3000_attribute_group,
.read_raw = &sca3000_read_raw,
.num_interrupt_lines = 1,
.event_attrs = &sca3000_event_attribute_group,
.read_event_value = &sca3000_read_thresh,
.write_event_value = &sca3000_write_thresh,
.read_event_config = &sca3000_read_event_config,
.write_event_config = &sca3000_write_event_config,
.driver_module = THIS_MODULE,
};
static const struct iio_info sca3000_info_with_temp = {
.attrs = &sca3000_attribute_group_with_temp,
.read_raw = &sca3000_read_raw,
.read_event_value = &sca3000_read_thresh,
.write_event_value = &sca3000_write_thresh,
.read_event_config = &sca3000_read_event_config,
.write_event_config = &sca3000_write_event_config,
.driver_module = THIS_MODULE,
};
static int __devinit sca3000_probe(struct spi_device *spi)
{
int ret, regdone = 0;
struct sca3000_state *st;
st = kzalloc(sizeof(struct sca3000_state), GFP_KERNEL);
if (st == NULL) {
ret = -ENOMEM;
goto error_ret;
}
spi_set_drvdata(spi, st);
st->us = spi;
mutex_init(&st->lock);
st->info = &sca3000_spi_chip_info_tbl[spi_get_device_id(spi)
->driver_data];
st->indio_dev = iio_allocate_device(0);
if (st->indio_dev == NULL) {
ret = -ENOMEM;
goto error_clear_st;
}
st->indio_dev->dev.parent = &spi->dev;
st->indio_dev->name = spi_get_device_id(spi)->name;
if (st->info->temp_output)
st->indio_dev->info = &sca3000_info_with_temp;
else {
st->indio_dev->info = &sca3000_info;
st->indio_dev->channels = sca3000_channels;
st->indio_dev->num_channels = ARRAY_SIZE(sca3000_channels);
}
st->indio_dev->dev_data = (void *)(st);
st->indio_dev->modes = INDIO_DIRECT_MODE;
sca3000_configure_ring(st->indio_dev);
ret = iio_device_register(st->indio_dev);
if (ret < 0)
goto error_free_dev;
regdone = 1;
ret = iio_ring_buffer_register_ex(st->indio_dev->ring, 0,
sca3000_channels,
ARRAY_SIZE(sca3000_channels));
if (ret < 0)
goto error_unregister_dev;
if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0) {
ret = request_threaded_irq(spi->irq,
NULL,
&sca3000_event_handler,
IRQF_TRIGGER_FALLING,
"sca3000",
st->indio_dev);
if (ret)
goto error_unregister_ring;
}
sca3000_register_ring_funcs(st->indio_dev);
ret = sca3000_clean_setup(st);
if (ret)
goto error_free_irq;
return 0;
error_free_irq:
if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0)
free_irq(spi->irq, st->indio_dev);
error_unregister_ring:
iio_ring_buffer_unregister(st->indio_dev->ring);
error_unregister_dev:
error_free_dev:
if (regdone)
iio_device_unregister(st->indio_dev);
else
iio_free_device(st->indio_dev);
error_clear_st:
kfree(st);
error_ret:
return ret;
}
static int sca3000_stop_all_interrupts(struct sca3000_state *st)
{
int ret;
mutex_lock(&st->lock);
ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_MASK, 1);
if (ret)
goto error_ret;
ret = sca3000_write_reg(st, SCA3000_REG_ADDR_INT_MASK,
(st->rx[0] &
~(SCA3000_INT_MASK_RING_THREE_QUARTER |
SCA3000_INT_MASK_RING_HALF |
SCA3000_INT_MASK_ALL_INTS)));
error_ret:
mutex_unlock(&st->lock);
return ret;
}
static int sca3000_remove(struct spi_device *spi)
{
struct sca3000_state *st = spi_get_drvdata(spi);
struct iio_dev *indio_dev = st->indio_dev;
int ret;
/* Must ensure no interrupts can be generated after this!*/
ret = sca3000_stop_all_interrupts(st);
if (ret)
return ret;
if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0)
free_irq(spi->irq, indio_dev);
iio_ring_buffer_unregister(indio_dev->ring);
sca3000_unconfigure_ring(indio_dev);
iio_device_unregister(indio_dev);
kfree(st);
return 0;
}
static const struct spi_device_id sca3000_id[] = {
{"sca3000_d01", d01},
{"sca3000_e02", e02},
{"sca3000_e04", e04},
{"sca3000_e05", e05},
{}
};
static struct spi_driver sca3000_driver = {
.driver = {
.name = "sca3000",
.owner = THIS_MODULE,
},
.probe = sca3000_probe,
.remove = __devexit_p(sca3000_remove),
.id_table = sca3000_id,
};
static __init int sca3000_init(void)
{
return spi_register_driver(&sca3000_driver);
}
module_init(sca3000_init);
static __exit void sca3000_exit(void)
{
spi_unregister_driver(&sca3000_driver);
}
module_exit(sca3000_exit);
MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>");
MODULE_DESCRIPTION("VTI SCA3000 Series Accelerometers SPI driver");
MODULE_LICENSE("GPL v2");