- 根目录:
- drivers
- staging
- iio
- resolver
- ad2s1210.c
/*
* ad2s1210.c support for the ADI Resolver to Digital Converters: AD2S1210
*
* Copyright (c) 2010-2010 Analog Devices Inc.
*
* 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.
*
*/
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/device.h>
#include <linux/spi/spi.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include "../iio.h"
#include "../sysfs.h"
#define DRV_NAME "ad2s1210"
#define DEF_CONTROL 0x7E
#define MSB_IS_HIGH 0x80
#define MSB_IS_LOW 0x7F
#define PHASE_LOCK_RANGE_44 0x20
#define ENABLE_HYSTERESIS 0x10
#define SET_ENRES1 0x08
#define SET_ENRES0 0x04
#define SET_RES1 0x02
#define SET_RES0 0x01
#define SET_ENRESOLUTION (SET_ENRES1 | SET_ENRES0)
#define SET_RESOLUTION (SET_RES1 | SET_RES0)
#define REG_POSITION 0x80
#define REG_VELOCITY 0x82
#define REG_LOS_THRD 0x88
#define REG_DOS_OVR_THRD 0x89
#define REG_DOS_MIS_THRD 0x8A
#define REG_DOS_RST_MAX_THRD 0x8B
#define REG_DOS_RST_MIN_THRD 0x8C
#define REG_LOT_HIGH_THRD 0x8D
#define REG_LOT_LOW_THRD 0x8E
#define REG_EXCIT_FREQ 0x91
#define REG_CONTROL 0x92
#define REG_SOFT_RESET 0xF0
#define REG_FAULT 0xFF
/* pin SAMPLE, A0, A1, RES0, RES1, is controlled by driver */
#define AD2S1210_SAA 3
#if defined(CONFIG_AD2S1210_GPIO_INPUT) || defined(CONFIG_AD2S1210_GPIO_OUTPUT)
# define AD2S1210_RES 2
#else
# define AD2S1210_RES 0
#endif
#define AD2S1210_PN (AD2S1210_SAA + AD2S1210_RES)
#define AD2S1210_MIN_CLKIN 6144000
#define AD2S1210_MAX_CLKIN 10240000
#define AD2S1210_MIN_EXCIT 2000
#define AD2S1210_MAX_EXCIT 20000
#define AD2S1210_MIN_FCW 0x4
#define AD2S1210_MAX_FCW 0x50
/* default input clock on serial interface */
#define AD2S1210_DEF_CLKIN 8192000
/* clock period in nano second */
#define AD2S1210_DEF_TCK (1000000000/AD2S1210_DEF_CLKIN)
#define AD2S1210_DEF_EXCIT 10000
enum ad2s1210_mode {
MOD_POS = 0,
MOD_VEL,
MOD_RESERVED,
MOD_CONFIG,
};
enum ad2s1210_res {
RES_10 = 10,
RES_12 = 12,
RES_14 = 14,
RES_16 = 16,
};
static unsigned int resolution_value[] = {
RES_10, RES_12, RES_14, RES_16};
struct ad2s1210_state {
struct mutex lock;
struct iio_dev *idev;
struct spi_device *sdev;
struct spi_transfer xfer;
unsigned int hysteresis;
unsigned int old_data;
enum ad2s1210_mode mode;
enum ad2s1210_res resolution;
unsigned int fclkin;
unsigned int fexcit;
unsigned short sample;
unsigned short a0;
unsigned short a1;
unsigned short res0;
unsigned short res1;
u8 rx[3];
u8 tx[3];
};
static inline void start_sample(struct ad2s1210_state *st)
{
gpio_set_value(st->sample, 0);
}
static inline void stop_sample(struct ad2s1210_state *st)
{
gpio_set_value(st->sample, 1);
}
static inline void set_mode(enum ad2s1210_mode mode, struct ad2s1210_state *st)
{
switch (mode) {
case MOD_POS:
gpio_set_value(st->a0, 0);
gpio_set_value(st->a1, 0);
break;
case MOD_VEL:
gpio_set_value(st->a0, 0);
gpio_set_value(st->a1, 1);
break;
case MOD_CONFIG:
gpio_set_value(st->a0, 1);
gpio_set_value(st->a1, 1);
break;
default:
/* set to reserved mode */
gpio_set_value(st->a0, 1);
gpio_set_value(st->a1, 0);
}
st->mode = mode;
}
/* write 1 bytes (address or data) to the chip */
static int config_write(struct ad2s1210_state *st,
unsigned char data)
{
struct spi_message msg;
int ret = 0;
st->xfer.len = 1;
set_mode(MOD_CONFIG, st);
spi_message_init(&msg);
spi_message_add_tail(&st->xfer, &msg);
st->tx[0] = data;
ret = spi_sync(st->sdev, &msg);
if (ret)
return ret;
st->old_data = 1;
return ret;
}
/* read value from one of the registers */
static int config_read(struct ad2s1210_state *st,
unsigned char address,
unsigned char *data)
{
struct spi_message msg;
int ret = 0;
st->xfer.len = 2;
set_mode(MOD_CONFIG, st);
spi_message_init(&msg);
spi_message_add_tail(&st->xfer, &msg);
st->tx[0] = address | MSB_IS_HIGH;
st->tx[1] = REG_FAULT;
ret = spi_sync(st->sdev, &msg);
if (ret)
return ret;
*data = st->rx[1];
st->old_data = 1;
return ret;
}
static inline void update_frequency_control_word(struct ad2s1210_state *st)
{
unsigned char fcw;
fcw = (unsigned char)(st->fexcit * (1 << 15) / st->fclkin);
if (fcw >= AD2S1210_MIN_FCW && fcw <= AD2S1210_MAX_FCW) {
config_write(st, REG_EXCIT_FREQ);
config_write(st, fcw);
} else
pr_err("ad2s1210: FCW out of range\n");
}
#if defined(CONFIG_AD2S1210_GPIO_INPUT)
static inline unsigned char read_resolution_pin(struct ad2s1210_state *st)
{
unsigned int data;
data = (gpio_get_value(st->res0) << 1) |
gpio_get_value(st->res1);
return resolution_value[data];
}
#elif defined(CONFIG_AD2S1210_GPIO_OUTPUT)
static inline void set_resolution_pin(struct ad2s1210_state *st)
{
switch (st->resolution) {
case RES_10:
gpio_set_value(st->res0, 0);
gpio_set_value(st->res1, 0);
break;
case RES_12:
gpio_set_value(st->res0, 0);
gpio_set_value(st->res1, 1);
break;
case RES_14:
gpio_set_value(st->res0, 1);
gpio_set_value(st->res1, 0);
break;
case RES_16:
gpio_set_value(st->res0, 1);
gpio_set_value(st->res1, 1);
break;
}
}
#endif
static inline void soft_reset(struct ad2s1210_state *st)
{
config_write(st, REG_SOFT_RESET);
config_write(st, 0x0);
}
/* return the OLD DATA since last spi bus write */
static ssize_t ad2s1210_show_raw(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
int ret;
mutex_lock(&st->lock);
if (st->old_data) {
ret = sprintf(buf, "0x%x\n", st->rx[0]);
st->old_data = 0;
} else
ret = 0;
mutex_unlock(&st->lock);
return ret;
}
static ssize_t ad2s1210_store_raw(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
unsigned long udata;
unsigned char data;
int ret;
ret = strict_strtoul(buf, 16, &udata);
if (ret)
return -EINVAL;
data = udata & 0xff;
mutex_lock(&st->lock);
config_write(st, data);
mutex_unlock(&st->lock);
return 1;
}
static ssize_t ad2s1210_store_softreset(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
mutex_lock(&st->lock);
soft_reset(st);
mutex_unlock(&st->lock);
return len;
}
static ssize_t ad2s1210_show_fclkin(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
return sprintf(buf, "%d\n", st->fclkin);
}
static ssize_t ad2s1210_store_fclkin(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
unsigned long fclkin;
int ret;
ret = strict_strtoul(buf, 10, &fclkin);
if (!ret && fclkin >= AD2S1210_MIN_CLKIN &&
fclkin <= AD2S1210_MAX_CLKIN) {
mutex_lock(&st->lock);
st->fclkin = fclkin;
} else {
pr_err("ad2s1210: fclkin out of range\n");
return -EINVAL;
}
update_frequency_control_word(st);
soft_reset(st);
mutex_unlock(&st->lock);
return len;
}
static ssize_t ad2s1210_show_fexcit(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
return sprintf(buf, "%d\n", st->fexcit);
}
static ssize_t ad2s1210_store_fexcit(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
unsigned long fexcit;
int ret;
ret = strict_strtoul(buf, 10, &fexcit);
if (!ret && fexcit >= AD2S1210_MIN_EXCIT &&
fexcit <= AD2S1210_MAX_EXCIT) {
mutex_lock(&st->lock);
st->fexcit = fexcit;
} else {
pr_err("ad2s1210: excitation frequency out of range\n");
return -EINVAL;
}
update_frequency_control_word(st);
soft_reset(st);
mutex_unlock(&st->lock);
return len;
}
static ssize_t ad2s1210_show_control(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
unsigned char data;
mutex_lock(&st->lock);
config_read(st, REG_CONTROL, &data);
mutex_unlock(&st->lock);
return sprintf(buf, "0x%x\n", data);
}
static ssize_t ad2s1210_store_control(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
unsigned long udata;
unsigned char data;
int ret;
ret = strict_strtoul(buf, 16, &udata);
if (ret) {
ret = -EINVAL;
goto error_ret;
}
mutex_lock(&st->lock);
config_write(st, REG_CONTROL);
data = udata & MSB_IS_LOW;
config_write(st, data);
config_read(st, REG_CONTROL, &data);
if (data & MSB_IS_HIGH) {
ret = -EIO;
pr_err("ad2s1210: write control register fail\n");
goto error_ret;
}
st->resolution = resolution_value[data & SET_RESOLUTION];
#if defined(CONFIG_AD2S1210_GPIO_INPUT)
data = read_resolution_pin(st);
if (data != st->resolution)
pr_warning("ad2s1210: resolution settings not match\n");
#elif defined(CONFIG_AD2S1210_GPIO_OUTPUT)
set_resolution_pin(st);
#endif
ret = len;
if (data & ENABLE_HYSTERESIS)
st->hysteresis = 1;
else
st->hysteresis = 0;
error_ret:
mutex_unlock(&st->lock);
return ret;
}
static ssize_t ad2s1210_show_resolution(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
return sprintf(buf, "%d\n", st->resolution);
}
static ssize_t ad2s1210_store_resolution(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
unsigned char data;
unsigned long udata;
int ret;
ret = strict_strtoul(buf, 10, &udata);
if (ret || udata < RES_10 || udata > RES_16) {
pr_err("ad2s1210: resolution out of range\n");
return -EINVAL;
}
mutex_lock(&st->lock);
config_read(st, REG_CONTROL, &data);
data &= ~SET_RESOLUTION;
data |= (udata - RES_10) >> 1;
config_write(st, REG_CONTROL);
config_write(st, data & MSB_IS_LOW);
config_read(st, REG_CONTROL, &data);
if (data & MSB_IS_HIGH) {
ret = -EIO;
pr_err("ad2s1210: setting resolution fail\n");
goto error_ret;
}
st->resolution = resolution_value[data & SET_RESOLUTION];
#if defined(CONFIG_AD2S1210_GPIO_INPUT)
data = read_resolution_pin(st);
if (data != st->resolution)
pr_warning("ad2s1210: resolution settings not match\n");
#elif defined(CONFIG_AD2S1210_GPIO_OUTPUT)
set_resolution_pin(st);
#endif
ret = len;
error_ret:
mutex_unlock(&st->lock);
return ret;
}
/* read the fault register since last sample */
static ssize_t ad2s1210_show_fault(struct device *dev,
struct device_attribute *attr, char *buf)
{
int ret = 0;
ssize_t len = 0;
unsigned char data;
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
mutex_lock(&st->lock);
ret = config_read(st, REG_FAULT, &data);
if (ret)
goto error_ret;
len = sprintf(buf, "0x%x\n", data);
error_ret:
mutex_unlock(&st->lock);
return ret ? ret : len;
}
static ssize_t ad2s1210_clear_fault(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
unsigned char data;
mutex_lock(&st->lock);
start_sample(st);
/* delay (2 * tck + 20) nano seconds */
udelay(1);
stop_sample(st);
config_read(st, REG_FAULT, &data);
start_sample(st);
stop_sample(st);
mutex_unlock(&st->lock);
return 0;
}
static ssize_t ad2s1210_show_reg(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
unsigned char data;
struct iio_dev_attr *iattr = to_iio_dev_attr(attr);
mutex_lock(&st->lock);
config_read(st, iattr->address, &data);
mutex_unlock(&st->lock);
return sprintf(buf, "%d\n", data);
}
static ssize_t ad2s1210_store_reg(struct device *dev,
struct device_attribute *attr, const char *buf, size_t len)
{
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
unsigned long data;
int ret;
struct iio_dev_attr *iattr = to_iio_dev_attr(attr);
ret = strict_strtoul(buf, 10, &data);
if (ret)
return -EINVAL;
mutex_lock(&st->lock);
config_write(st, iattr->address);
config_write(st, data & MSB_IS_LOW);
mutex_unlock(&st->lock);
return len;
}
static ssize_t ad2s1210_show_pos(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct spi_message msg;
int ret = 0;
ssize_t len = 0;
u16 pos;
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
st->xfer.len = 2;
mutex_lock(&st->lock);
start_sample(st);
/* delay (6 * tck + 20) nano seconds */
udelay(1);
set_mode(MOD_POS, st);
spi_message_init(&msg);
spi_message_add_tail(&st->xfer, &msg);
ret = spi_sync(st->sdev, &msg);
if (ret)
goto error_ret;
pos = ((((u16)(st->rx[0])) << 8) | (st->rx[1]));
if (st->hysteresis)
pos >>= 16 - st->resolution;
len = sprintf(buf, "%d\n", pos);
error_ret:
stop_sample(st);
/* delay (2 * tck + 20) nano seconds */
udelay(1);
mutex_unlock(&st->lock);
return ret ? ret : len;
}
static ssize_t ad2s1210_show_vel(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct spi_message msg;
unsigned short negative;
int ret = 0;
ssize_t len = 0;
s16 vel;
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
st->xfer.len = 2;
mutex_lock(&st->lock);
start_sample(st);
/* delay (6 * tck + 20) nano seconds */
udelay(1);
set_mode(MOD_VEL, st);
spi_message_init(&msg);
spi_message_add_tail(&st->xfer, &msg);
ret = spi_sync(st->sdev, &msg);
if (ret)
goto error_ret;
negative = st->rx[0] & 0x80;
vel = ((((s16)(st->rx[0])) << 8) | (st->rx[1]));
vel >>= 16 - st->resolution;
if (negative) {
negative = (0xffff >> st->resolution) << st->resolution;
vel |= negative;
}
len = sprintf(buf, "%d\n", vel);
error_ret:
stop_sample(st);
/* delay (2 * tck + 20) nano seconds */
udelay(1);
mutex_unlock(&st->lock);
return ret ? ret : len;
}
static ssize_t ad2s1210_show_pos_vel(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct spi_message msg;
unsigned short negative;
int ret = 0;
ssize_t len = 0;
u16 pos;
s16 vel;
struct iio_dev *idev = dev_get_drvdata(dev);
struct ad2s1210_state *st = idev->dev_data;
st->xfer.len = 2;
mutex_lock(&st->lock);
start_sample(st);
/* delay (6 * tck + 20) nano seconds */
udelay(1);
set_mode(MOD_POS, st);
spi_message_init(&msg);
spi_message_add_tail(&st->xfer, &msg);
ret = spi_sync(st->sdev, &msg);
if (ret)
goto error_ret;
pos = ((((u16)(st->rx[0])) << 8) | (st->rx[1]));
if (st->hysteresis)
pos >>= 16 - st->resolution;
len = sprintf(buf, "%d ", pos);
st->xfer.len = 2;
set_mode(MOD_VEL, st);
spi_message_init(&msg);
spi_message_add_tail(&st->xfer, &msg);
ret = spi_sync(st->sdev, &msg);
if (ret)
goto error_ret;
negative = st->rx[0] & 0x80;
vel = ((((s16)(st->rx[0])) << 8) | (st->rx[1]));
vel >>= 16 - st->resolution;
if (negative) {
negative = (0xffff >> st->resolution) << st->resolution;
vel |= negative;
}
len += sprintf(buf + len, "%d\n", vel);
error_ret:
stop_sample(st);
/* delay (2 * tck + 20) nano seconds */
udelay(1);
mutex_unlock(&st->lock);
return ret ? ret : len;
}
static IIO_CONST_ATTR(description,
"Variable Resolution, 10-Bit to 16Bit R/D\n\
Converter with Reference Oscillator");
static IIO_DEVICE_ATTR(raw_io, S_IRUGO | S_IWUSR,
ad2s1210_show_raw, ad2s1210_store_raw, 0);
static IIO_DEVICE_ATTR(reset, S_IWUSR,
NULL, ad2s1210_store_softreset, 0);
static IIO_DEVICE_ATTR(fclkin, S_IRUGO | S_IWUSR,
ad2s1210_show_fclkin, ad2s1210_store_fclkin, 0);
static IIO_DEVICE_ATTR(fexcit, S_IRUGO | S_IWUSR,
ad2s1210_show_fexcit, ad2s1210_store_fexcit, 0);
static IIO_DEVICE_ATTR(control, S_IRUGO | S_IWUSR,
ad2s1210_show_control, ad2s1210_store_control, 0);
static IIO_DEVICE_ATTR(bits, S_IRUGO | S_IWUSR,
ad2s1210_show_resolution, ad2s1210_store_resolution, 0);
static IIO_DEVICE_ATTR(fault, S_IRUGO | S_IWUSR,
ad2s1210_show_fault, ad2s1210_clear_fault, 0);
static IIO_DEVICE_ATTR(pos, S_IRUGO,
ad2s1210_show_pos, NULL, 0);
static IIO_DEVICE_ATTR(vel, S_IRUGO,
ad2s1210_show_vel, NULL, 0);
static IIO_DEVICE_ATTR(pos_vel, S_IRUGO,
ad2s1210_show_pos_vel, NULL, 0);
static IIO_DEVICE_ATTR(los_thrd, S_IRUGO | S_IWUSR,
ad2s1210_show_reg, ad2s1210_store_reg, REG_LOS_THRD);
static IIO_DEVICE_ATTR(dos_ovr_thrd, S_IRUGO | S_IWUSR,
ad2s1210_show_reg, ad2s1210_store_reg, REG_DOS_OVR_THRD);
static IIO_DEVICE_ATTR(dos_mis_thrd, S_IRUGO | S_IWUSR,
ad2s1210_show_reg, ad2s1210_store_reg, REG_DOS_MIS_THRD);
static IIO_DEVICE_ATTR(dos_rst_max_thrd, S_IRUGO | S_IWUSR,
ad2s1210_show_reg, ad2s1210_store_reg, REG_DOS_RST_MAX_THRD);
static IIO_DEVICE_ATTR(dos_rst_min_thrd, S_IRUGO | S_IWUSR,
ad2s1210_show_reg, ad2s1210_store_reg, REG_DOS_RST_MIN_THRD);
static IIO_DEVICE_ATTR(lot_high_thrd, S_IRUGO | S_IWUSR,
ad2s1210_show_reg, ad2s1210_store_reg, REG_LOT_HIGH_THRD);
static IIO_DEVICE_ATTR(lot_low_thrd, S_IRUGO | S_IWUSR,
ad2s1210_show_reg, ad2s1210_store_reg, REG_LOT_LOW_THRD);
static struct attribute *ad2s1210_attributes[] = {
&iio_const_attr_description.dev_attr.attr,
&iio_dev_attr_raw_io.dev_attr.attr,
&iio_dev_attr_reset.dev_attr.attr,
&iio_dev_attr_fclkin.dev_attr.attr,
&iio_dev_attr_fexcit.dev_attr.attr,
&iio_dev_attr_control.dev_attr.attr,
&iio_dev_attr_bits.dev_attr.attr,
&iio_dev_attr_fault.dev_attr.attr,
&iio_dev_attr_pos.dev_attr.attr,
&iio_dev_attr_vel.dev_attr.attr,
&iio_dev_attr_pos_vel.dev_attr.attr,
&iio_dev_attr_los_thrd.dev_attr.attr,
&iio_dev_attr_dos_ovr_thrd.dev_attr.attr,
&iio_dev_attr_dos_mis_thrd.dev_attr.attr,
&iio_dev_attr_dos_rst_max_thrd.dev_attr.attr,
&iio_dev_attr_dos_rst_min_thrd.dev_attr.attr,
&iio_dev_attr_lot_high_thrd.dev_attr.attr,
&iio_dev_attr_lot_low_thrd.dev_attr.attr,
NULL,
};
static const struct attribute_group ad2s1210_attribute_group = {
.name = DRV_NAME,
.attrs = ad2s1210_attributes,
};
static int __devinit ad2s1210_initial(struct ad2s1210_state *st)
{
unsigned char data;
int ret;
mutex_lock(&st->lock);
#if defined(CONFIG_AD2S1210_GPIO_INPUT)
st->resolution = read_resolution_pin(st);
#elif defined(CONFIG_AD2S1210_GPIO_OUTPUT)
set_resolution_pin(st);
#endif
config_write(st, REG_CONTROL);
data = DEF_CONTROL & ~(SET_RESOLUTION);
data |= (st->resolution - RES_10) >> 1;
config_write(st, data);
ret = config_read(st, REG_CONTROL, &data);
if (ret)
goto error_ret;
if (data & MSB_IS_HIGH) {
ret = -EIO;
goto error_ret;
}
update_frequency_control_word(st);
soft_reset(st);
error_ret:
mutex_unlock(&st->lock);
return ret;
}
static int __devinit ad2s1210_probe(struct spi_device *spi)
{
struct ad2s1210_state *st;
int pn, ret = 0;
unsigned short *pins = spi->dev.platform_data;
for (pn = 0; pn < AD2S1210_PN; pn++) {
if (gpio_request(pins[pn], DRV_NAME)) {
pr_err("%s: request gpio pin %d failed\n",
DRV_NAME, pins[pn]);
goto error_ret;
}
if (pn < AD2S1210_SAA)
gpio_direction_output(pins[pn], 1);
else {
#if defined(CONFIG_AD2S1210_GPIO_INPUT)
gpio_direction_input(pins[pn]);
#elif defined(CONFIG_AD2S1210_GPIO_OUTPUT)
gpio_direction_output(pins[pn], 1);
#endif
}
}
st = kzalloc(sizeof(*st), GFP_KERNEL);
if (st == NULL) {
ret = -ENOMEM;
goto error_ret;
}
spi_set_drvdata(spi, st);
mutex_init(&st->lock);
st->sdev = spi;
st->xfer.tx_buf = st->tx;
st->xfer.rx_buf = st->rx;
st->hysteresis = 1;
st->mode = MOD_CONFIG;
st->resolution = RES_12;
st->fclkin = AD2S1210_DEF_CLKIN;
st->fexcit = AD2S1210_DEF_EXCIT;
st->sample = pins[0];
st->a0 = pins[1];
st->a1 = pins[2];
st->res0 = pins[3];
st->res1 = pins[4];
st->idev = iio_allocate_device();
if (st->idev == NULL) {
ret = -ENOMEM;
goto error_free_st;
}
st->idev->dev.parent = &spi->dev;
st->idev->num_interrupt_lines = 0;
st->idev->event_attrs = NULL;
st->idev->attrs = &ad2s1210_attribute_group;
st->idev->dev_data = (void *)(st);
st->idev->driver_module = THIS_MODULE;
st->idev->modes = INDIO_DIRECT_MODE;
ret = iio_device_register(st->idev);
if (ret)
goto error_free_dev;
if (spi->max_speed_hz != AD2S1210_DEF_CLKIN)
st->fclkin = spi->max_speed_hz;
spi->mode = SPI_MODE_3;
spi_setup(spi);
ad2s1210_initial(st);
return 0;
error_free_dev:
iio_free_device(st->idev);
error_free_st:
kfree(st);
error_ret:
for (--pn; pn >= 0; pn--)
gpio_free(pins[pn]);
return ret;
}
static int __devexit ad2s1210_remove(struct spi_device *spi)
{
struct ad2s1210_state *st = spi_get_drvdata(spi);
iio_device_unregister(st->idev);
kfree(st);
return 0;
}
static struct spi_driver ad2s1210_driver = {
.driver = {
.name = DRV_NAME,
.owner = THIS_MODULE,
},
.probe = ad2s1210_probe,
.remove = __devexit_p(ad2s1210_remove),
};
static __init int ad2s1210_spi_init(void)
{
return spi_register_driver(&ad2s1210_driver);
}
module_init(ad2s1210_spi_init);
static __exit void ad2s1210_spi_exit(void)
{
spi_unregister_driver(&ad2s1210_driver);
}
module_exit(ad2s1210_spi_exit);
MODULE_AUTHOR("Graff Yang <graff.yang@gmail.com>");
MODULE_DESCRIPTION("Analog Devices AD2S1210 Resolver to Digital SPI driver");
MODULE_LICENSE("GPL v2");