/*
* AD7280A Lithium Ion Battery Monitoring System
*
* Copyright 2011 Analog Devices Inc.
*
* Licensed under the GPL-2.
*/
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/spi/spi.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/events.h>
#include "ad7280a.h"
/* Registers */
#define AD7280A_CELL_VOLTAGE_1 0x0 /* D11 to D0, Read only */
#define AD7280A_CELL_VOLTAGE_2 0x1 /* D11 to D0, Read only */
#define AD7280A_CELL_VOLTAGE_3 0x2 /* D11 to D0, Read only */
#define AD7280A_CELL_VOLTAGE_4 0x3 /* D11 to D0, Read only */
#define AD7280A_CELL_VOLTAGE_5 0x4 /* D11 to D0, Read only */
#define AD7280A_CELL_VOLTAGE_6 0x5 /* D11 to D0, Read only */
#define AD7280A_AUX_ADC_1 0x6 /* D11 to D0, Read only */
#define AD7280A_AUX_ADC_2 0x7 /* D11 to D0, Read only */
#define AD7280A_AUX_ADC_3 0x8 /* D11 to D0, Read only */
#define AD7280A_AUX_ADC_4 0x9 /* D11 to D0, Read only */
#define AD7280A_AUX_ADC_5 0xA /* D11 to D0, Read only */
#define AD7280A_AUX_ADC_6 0xB /* D11 to D0, Read only */
#define AD7280A_SELF_TEST 0xC /* D11 to D0, Read only */
#define AD7280A_CONTROL_HB 0xD /* D15 to D8, Read/write */
#define AD7280A_CONTROL_LB 0xE /* D7 to D0, Read/write */
#define AD7280A_CELL_OVERVOLTAGE 0xF /* D7 to D0, Read/write */
#define AD7280A_CELL_UNDERVOLTAGE 0x10 /* D7 to D0, Read/write */
#define AD7280A_AUX_ADC_OVERVOLTAGE 0x11 /* D7 to D0, Read/write */
#define AD7280A_AUX_ADC_UNDERVOLTAGE 0x12 /* D7 to D0, Read/write */
#define AD7280A_ALERT 0x13 /* D7 to D0, Read/write */
#define AD7280A_CELL_BALANCE 0x14 /* D7 to D0, Read/write */
#define AD7280A_CB1_TIMER 0x15 /* D7 to D0, Read/write */
#define AD7280A_CB2_TIMER 0x16 /* D7 to D0, Read/write */
#define AD7280A_CB3_TIMER 0x17 /* D7 to D0, Read/write */
#define AD7280A_CB4_TIMER 0x18 /* D7 to D0, Read/write */
#define AD7280A_CB5_TIMER 0x19 /* D7 to D0, Read/write */
#define AD7280A_CB6_TIMER 0x1A /* D7 to D0, Read/write */
#define AD7280A_PD_TIMER 0x1B /* D7 to D0, Read/write */
#define AD7280A_READ 0x1C /* D7 to D0, Read/write */
#define AD7280A_CNVST_CONTROL 0x1D /* D7 to D0, Read/write */
/* Bits and Masks */
#define AD7280A_CTRL_HB_CONV_INPUT_ALL (0 << 6)
#define AD7280A_CTRL_HB_CONV_INPUT_6CELL_AUX1_3_4 (1 << 6)
#define AD7280A_CTRL_HB_CONV_INPUT_6CELL (2 << 6)
#define AD7280A_CTRL_HB_CONV_INPUT_SELF_TEST (3 << 6)
#define AD7280A_CTRL_HB_CONV_RES_READ_ALL (0 << 4)
#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL_AUX1_3_4 (1 << 4)
#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL (2 << 4)
#define AD7280A_CTRL_HB_CONV_RES_READ_NO (3 << 4)
#define AD7280A_CTRL_HB_CONV_START_CNVST (0 << 3)
#define AD7280A_CTRL_HB_CONV_START_CS (1 << 3)
#define AD7280A_CTRL_HB_CONV_AVG_DIS (0 << 1)
#define AD7280A_CTRL_HB_CONV_AVG_2 (1 << 1)
#define AD7280A_CTRL_HB_CONV_AVG_4 (2 << 1)
#define AD7280A_CTRL_HB_CONV_AVG_8 (3 << 1)
#define AD7280A_CTRL_HB_CONV_AVG(x) ((x) << 1)
#define AD7280A_CTRL_HB_PWRDN_SW (1 << 0)
#define AD7280A_CTRL_LB_SWRST (1 << 7)
#define AD7280A_CTRL_LB_ACQ_TIME_400ns (0 << 5)
#define AD7280A_CTRL_LB_ACQ_TIME_800ns (1 << 5)
#define AD7280A_CTRL_LB_ACQ_TIME_1200ns (2 << 5)
#define AD7280A_CTRL_LB_ACQ_TIME_1600ns (3 << 5)
#define AD7280A_CTRL_LB_ACQ_TIME(x) ((x) << 5)
#define AD7280A_CTRL_LB_MUST_SET (1 << 4)
#define AD7280A_CTRL_LB_THERMISTOR_EN (1 << 3)
#define AD7280A_CTRL_LB_LOCK_DEV_ADDR (1 << 2)
#define AD7280A_CTRL_LB_INC_DEV_ADDR (1 << 1)
#define AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN (1 << 0)
#define AD7280A_ALERT_GEN_STATIC_HIGH (1 << 6)
#define AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN (3 << 6)
#define AD7280A_ALL_CELLS (0xAD << 16)
#define AD7280A_MAX_SPI_CLK_Hz 700000 /* < 1MHz */
#define AD7280A_MAX_CHAIN 8
#define AD7280A_CELLS_PER_DEV 6
#define AD7280A_BITS 12
#define AD7280A_NUM_CH (AD7280A_AUX_ADC_6 - \
AD7280A_CELL_VOLTAGE_1 + 1)
#define AD7280A_DEVADDR_MASTER 0
#define AD7280A_DEVADDR_ALL 0x1F
/* 5-bit device address is sent LSB first */
#define AD7280A_DEVADDR(addr) (((addr & 0x1) << 4) | ((addr & 0x2) << 3) | \
(addr & 0x4) | ((addr & 0x8) >> 3) | \
((addr & 0x10) >> 4))
/* During a read a valid write is mandatory.
* So writing to the highest available address (Address 0x1F)
* and setting the address all parts bit to 0 is recommended
* So the TXVAL is AD7280A_DEVADDR_ALL + CRC
*/
#define AD7280A_READ_TXVAL 0xF800030A
/*
* AD7280 CRC
*
* P(x) = x^8 + x^5 + x^3 + x^2 + x^1 + x^0 = 0b100101111 => 0x2F
*/
#define POLYNOM 0x2F
#define POLYNOM_ORDER 8
#define HIGHBIT 1 << (POLYNOM_ORDER - 1);
struct ad7280_state {
struct spi_device *spi;
struct iio_chan_spec *channels;
struct iio_dev_attr *iio_attr;
int slave_num;
int scan_cnt;
int readback_delay_us;
unsigned char crc_tab[256];
unsigned char ctrl_hb;
unsigned char ctrl_lb;
unsigned char cell_threshhigh;
unsigned char cell_threshlow;
unsigned char aux_threshhigh;
unsigned char aux_threshlow;
unsigned char cb_mask[AD7280A_MAX_CHAIN];
};
static void ad7280_crc8_build_table(unsigned char *crc_tab)
{
unsigned char bit, crc;
int cnt, i;
for (cnt = 0; cnt < 256; cnt++) {
crc = cnt;
for (i = 0; i < 8; i++) {
bit = crc & HIGHBIT;
crc <<= 1;
if (bit)
crc ^= POLYNOM;
}
crc_tab[cnt] = crc;
}
}
static unsigned char ad7280_calc_crc8(unsigned char *crc_tab, unsigned val)
{
unsigned char crc;
crc = crc_tab[val >> 16 & 0xFF];
crc = crc_tab[crc ^ (val >> 8 & 0xFF)];
return crc ^ (val & 0xFF);
}
static int ad7280_check_crc(struct ad7280_state *st, unsigned val)
{
unsigned char crc = ad7280_calc_crc8(st->crc_tab, val >> 10);
if (crc != ((val >> 2) & 0xFF))
return -EIO;
return 0;
}
/* After initiating a conversion sequence we need to wait until the
* conversion is done. The delay is typically in the range of 15..30 us
* however depending an the number of devices in the daisy chain and the
* number of averages taken, conversion delays and acquisition time options
* it may take up to 250us, in this case we better sleep instead of busy
* wait.
*/
static void ad7280_delay(struct ad7280_state *st)
{
if (st->readback_delay_us < 50)
udelay(st->readback_delay_us);
else
msleep(1);
}
static int __ad7280_read32(struct spi_device *spi, unsigned *val)
{
unsigned rx_buf, tx_buf = cpu_to_be32(AD7280A_READ_TXVAL);
int ret;
struct spi_transfer t = {
.tx_buf = &tx_buf,
.rx_buf = &rx_buf,
.len = 4,
};
struct spi_message m;
spi_message_init(&m);
spi_message_add_tail(&t, &m);
ret = spi_sync(spi, &m);
if (ret)
return ret;
*val = be32_to_cpu(rx_buf);
return 0;
}
static int ad7280_write(struct ad7280_state *st, unsigned devaddr,
unsigned addr, bool all, unsigned val)
{
unsigned reg = (devaddr << 27 | addr << 21 |
(val & 0xFF) << 13 | all << 12);
reg |= ad7280_calc_crc8(st->crc_tab, reg >> 11) << 3 | 0x2;
reg = cpu_to_be32(reg);
return spi_write(st->spi, ®, 4);
}
static int ad7280_read(struct ad7280_state *st, unsigned devaddr,
unsigned addr)
{
int ret;
unsigned tmp;
/* turns off the read operation on all parts */
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
AD7280A_CTRL_HB_CONV_INPUT_ALL |
AD7280A_CTRL_HB_CONV_RES_READ_NO |
st->ctrl_hb);
if (ret)
return ret;
/* turns on the read operation on the addressed part */
ret = ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
AD7280A_CTRL_HB_CONV_INPUT_ALL |
AD7280A_CTRL_HB_CONV_RES_READ_ALL |
st->ctrl_hb);
if (ret)
return ret;
/* Set register address on the part to be read from */
ret = ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
if (ret)
return ret;
__ad7280_read32(st->spi, &tmp);
if (ad7280_check_crc(st, tmp))
return -EIO;
if (((tmp >> 27) != devaddr) || (((tmp >> 21) & 0x3F) != addr))
return -EFAULT;
return (tmp >> 13) & 0xFF;
}
static int ad7280_read_channel(struct ad7280_state *st, unsigned devaddr,
unsigned addr)
{
int ret;
unsigned tmp;
ret = ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
if (ret)
return ret;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
AD7280A_CTRL_HB_CONV_INPUT_ALL |
AD7280A_CTRL_HB_CONV_RES_READ_NO |
st->ctrl_hb);
if (ret)
return ret;
ret = ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
AD7280A_CTRL_HB_CONV_INPUT_ALL |
AD7280A_CTRL_HB_CONV_RES_READ_ALL |
AD7280A_CTRL_HB_CONV_START_CS |
st->ctrl_hb);
if (ret)
return ret;
ad7280_delay(st);
__ad7280_read32(st->spi, &tmp);
if (ad7280_check_crc(st, tmp))
return -EIO;
if (((tmp >> 27) != devaddr) || (((tmp >> 23) & 0xF) != addr))
return -EFAULT;
return (tmp >> 11) & 0xFFF;
}
static int ad7280_read_all_channels(struct ad7280_state *st, unsigned cnt,
unsigned *array)
{
int i, ret;
unsigned tmp, sum = 0;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
AD7280A_CELL_VOLTAGE_1 << 2);
if (ret)
return ret;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
AD7280A_CTRL_HB_CONV_INPUT_ALL |
AD7280A_CTRL_HB_CONV_RES_READ_ALL |
AD7280A_CTRL_HB_CONV_START_CS |
st->ctrl_hb);
if (ret)
return ret;
ad7280_delay(st);
for (i = 0; i < cnt; i++) {
__ad7280_read32(st->spi, &tmp);
if (ad7280_check_crc(st, tmp))
return -EIO;
if (array)
array[i] = tmp;
/* only sum cell voltages */
if (((tmp >> 23) & 0xF) <= AD7280A_CELL_VOLTAGE_6)
sum += ((tmp >> 11) & 0xFFF);
}
return sum;
}
static int ad7280_chain_setup(struct ad7280_state *st)
{
unsigned val, n;
int ret;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB, 1,
AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
AD7280A_CTRL_LB_LOCK_DEV_ADDR |
AD7280A_CTRL_LB_MUST_SET |
AD7280A_CTRL_LB_SWRST |
st->ctrl_lb);
if (ret)
return ret;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB, 1,
AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
AD7280A_CTRL_LB_LOCK_DEV_ADDR |
AD7280A_CTRL_LB_MUST_SET |
st->ctrl_lb);
if (ret)
return ret;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
AD7280A_CONTROL_LB << 2);
if (ret)
return ret;
for (n = 0; n <= AD7280A_MAX_CHAIN; n++) {
__ad7280_read32(st->spi, &val);
if (val == 0)
return n - 1;
if (ad7280_check_crc(st, val))
return -EIO;
if (n != AD7280A_DEVADDR(val >> 27))
return -EIO;
}
return -EFAULT;
}
static ssize_t ad7280_show_balance_sw(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct ad7280_state *st = iio_priv(indio_dev);
struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
return sprintf(buf, "%d\n",
!!(st->cb_mask[this_attr->address >> 8] &
(1 << ((this_attr->address & 0xFF) + 2))));
}
static ssize_t ad7280_store_balance_sw(struct device *dev,
struct device_attribute *attr,
const char *buf,
size_t len)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct ad7280_state *st = iio_priv(indio_dev);
struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
bool readin;
int ret;
unsigned devaddr, ch;
ret = strtobool(buf, &readin);
if (ret)
return ret;
devaddr = this_attr->address >> 8;
ch = this_attr->address & 0xFF;
mutex_lock(&indio_dev->mlock);
if (readin)
st->cb_mask[devaddr] |= 1 << (ch + 2);
else
st->cb_mask[devaddr] &= ~(1 << (ch + 2));
ret = ad7280_write(st, devaddr, AD7280A_CELL_BALANCE,
0, st->cb_mask[devaddr]);
mutex_unlock(&indio_dev->mlock);
return ret ? ret : len;
}
static ssize_t ad7280_show_balance_timer(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct ad7280_state *st = iio_priv(indio_dev);
struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
int ret;
unsigned msecs;
mutex_lock(&indio_dev->mlock);
ret = ad7280_read(st, this_attr->address >> 8,
this_attr->address & 0xFF);
mutex_unlock(&indio_dev->mlock);
if (ret < 0)
return ret;
msecs = (ret >> 3) * 71500;
return sprintf(buf, "%d\n", msecs);
}
static ssize_t ad7280_store_balance_timer(struct device *dev,
struct device_attribute *attr,
const char *buf,
size_t len)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct ad7280_state *st = iio_priv(indio_dev);
struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
unsigned long val;
int ret;
ret = kstrtoul(buf, 10, &val);
if (ret)
return ret;
val /= 71500;
if (val > 31)
return -EINVAL;
mutex_lock(&indio_dev->mlock);
ret = ad7280_write(st, this_attr->address >> 8,
this_attr->address & 0xFF,
0, (val & 0x1F) << 3);
mutex_unlock(&indio_dev->mlock);
return ret ? ret : len;
}
static struct attribute *ad7280_attributes[AD7280A_MAX_CHAIN *
AD7280A_CELLS_PER_DEV * 2 + 1];
static struct attribute_group ad7280_attrs_group = {
.attrs = ad7280_attributes,
};
static int ad7280_channel_init(struct ad7280_state *st)
{
int dev, ch, cnt;
st->channels = kcalloc((st->slave_num + 1) * 12 + 2,
sizeof(*st->channels), GFP_KERNEL);
if (st->channels == NULL)
return -ENOMEM;
for (dev = 0, cnt = 0; dev <= st->slave_num; dev++)
for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_AUX_ADC_6; ch++,
cnt++) {
if (ch < AD7280A_AUX_ADC_1) {
st->channels[cnt].type = IIO_VOLTAGE;
st->channels[cnt].differential = 1;
st->channels[cnt].channel = (dev * 6) + ch;
st->channels[cnt].channel2 =
st->channels[cnt].channel + 1;
} else {
st->channels[cnt].type = IIO_TEMP;
st->channels[cnt].channel = (dev * 6) + ch - 6;
}
st->channels[cnt].indexed = 1;
st->channels[cnt].info_mask =
IIO_CHAN_INFO_RAW_SEPARATE_BIT |
IIO_CHAN_INFO_SCALE_SHARED_BIT;
st->channels[cnt].address =
AD7280A_DEVADDR(dev) << 8 | ch;
st->channels[cnt].scan_index = cnt;
st->channels[cnt].scan_type.sign = 'u';
st->channels[cnt].scan_type.realbits = 12;
st->channels[cnt].scan_type.storagebits = 32;
st->channels[cnt].scan_type.shift = 0;
}
st->channels[cnt].type = IIO_VOLTAGE;
st->channels[cnt].differential = 1;
st->channels[cnt].channel = 0;
st->channels[cnt].channel2 = dev * 6;
st->channels[cnt].address = AD7280A_ALL_CELLS;
st->channels[cnt].indexed = 1;
st->channels[cnt].info_mask =
IIO_CHAN_INFO_RAW_SEPARATE_BIT |
IIO_CHAN_INFO_SCALE_SHARED_BIT;
st->channels[cnt].scan_index = cnt;
st->channels[cnt].scan_type.sign = 'u';
st->channels[cnt].scan_type.realbits = 32;
st->channels[cnt].scan_type.storagebits = 32;
st->channels[cnt].scan_type.shift = 0;
cnt++;
st->channels[cnt].type = IIO_TIMESTAMP;
st->channels[cnt].channel = -1;
st->channels[cnt].scan_index = cnt;
st->channels[cnt].scan_type.sign = 's';
st->channels[cnt].scan_type.realbits = 64;
st->channels[cnt].scan_type.storagebits = 64;
st->channels[cnt].scan_type.shift = 0;
return cnt + 1;
}
static int ad7280_attr_init(struct ad7280_state *st)
{
int dev, ch, cnt;
st->iio_attr = kzalloc(sizeof(*st->iio_attr) * (st->slave_num + 1) *
AD7280A_CELLS_PER_DEV * 2, GFP_KERNEL);
if (st->iio_attr == NULL)
return -ENOMEM;
for (dev = 0, cnt = 0; dev <= st->slave_num; dev++)
for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_CELL_VOLTAGE_6;
ch++, cnt++) {
st->iio_attr[cnt].address =
AD7280A_DEVADDR(dev) << 8 | ch;
st->iio_attr[cnt].dev_attr.attr.mode =
S_IWUSR | S_IRUGO;
st->iio_attr[cnt].dev_attr.show =
ad7280_show_balance_sw;
st->iio_attr[cnt].dev_attr.store =
ad7280_store_balance_sw;
st->iio_attr[cnt].dev_attr.attr.name =
kasprintf(GFP_KERNEL,
"in%d-in%d_balance_switch_en",
(dev * AD7280A_CELLS_PER_DEV) + ch,
(dev * AD7280A_CELLS_PER_DEV) + ch + 1);
ad7280_attributes[cnt] =
&st->iio_attr[cnt].dev_attr.attr;
cnt++;
st->iio_attr[cnt].address =
AD7280A_DEVADDR(dev) << 8 |
(AD7280A_CB1_TIMER + ch);
st->iio_attr[cnt].dev_attr.attr.mode =
S_IWUSR | S_IRUGO;
st->iio_attr[cnt].dev_attr.show =
ad7280_show_balance_timer;
st->iio_attr[cnt].dev_attr.store =
ad7280_store_balance_timer;
st->iio_attr[cnt].dev_attr.attr.name =
kasprintf(GFP_KERNEL, "in%d-in%d_balance_timer",
(dev * AD7280A_CELLS_PER_DEV) + ch,
(dev * AD7280A_CELLS_PER_DEV) + ch + 1);
ad7280_attributes[cnt] =
&st->iio_attr[cnt].dev_attr.attr;
}
ad7280_attributes[cnt] = NULL;
return 0;
}
static ssize_t ad7280_read_channel_config(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct ad7280_state *st = iio_priv(indio_dev);
struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
unsigned val;
switch ((u32) this_attr->address) {
case AD7280A_CELL_OVERVOLTAGE:
val = 1000 + (st->cell_threshhigh * 1568) / 100;
break;
case AD7280A_CELL_UNDERVOLTAGE:
val = 1000 + (st->cell_threshlow * 1568) / 100;
break;
case AD7280A_AUX_ADC_OVERVOLTAGE:
val = (st->aux_threshhigh * 196) / 10;
break;
case AD7280A_AUX_ADC_UNDERVOLTAGE:
val = (st->aux_threshlow * 196) / 10;
break;
default:
return -EINVAL;
}
return sprintf(buf, "%d\n", val);
}
static ssize_t ad7280_write_channel_config(struct device *dev,
struct device_attribute *attr,
const char *buf,
size_t len)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct ad7280_state *st = iio_priv(indio_dev);
struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
long val;
int ret;
ret = strict_strtol(buf, 10, &val);
if (ret)
return ret;
switch ((u32) this_attr->address) {
case AD7280A_CELL_OVERVOLTAGE:
case AD7280A_CELL_UNDERVOLTAGE:
val = ((val - 1000) * 100) / 1568; /* LSB 15.68mV */
break;
case AD7280A_AUX_ADC_OVERVOLTAGE:
case AD7280A_AUX_ADC_UNDERVOLTAGE:
val = (val * 10) / 196; /* LSB 19.6mV */
break;
default:
return -EFAULT;
}
val = clamp(val, 0L, 0xFFL);
mutex_lock(&indio_dev->mlock);
switch ((u32) this_attr->address) {
case AD7280A_CELL_OVERVOLTAGE:
st->cell_threshhigh = val;
break;
case AD7280A_CELL_UNDERVOLTAGE:
st->cell_threshlow = val;
break;
case AD7280A_AUX_ADC_OVERVOLTAGE:
st->aux_threshhigh = val;
break;
case AD7280A_AUX_ADC_UNDERVOLTAGE:
st->aux_threshlow = val;
break;
}
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
this_attr->address, 1, val);
mutex_unlock(&indio_dev->mlock);
return ret ? ret : len;
}
static irqreturn_t ad7280_event_handler(int irq, void *private)
{
struct iio_dev *indio_dev = private;
struct ad7280_state *st = iio_priv(indio_dev);
unsigned *channels;
int i, ret;
channels = kcalloc(st->scan_cnt, sizeof(*channels), GFP_KERNEL);
if (channels == NULL)
return IRQ_HANDLED;
ret = ad7280_read_all_channels(st, st->scan_cnt, channels);
if (ret < 0)
goto out;
for (i = 0; i < st->scan_cnt; i++) {
if (((channels[i] >> 23) & 0xF) <= AD7280A_CELL_VOLTAGE_6) {
if (((channels[i] >> 11) & 0xFFF) >=
st->cell_threshhigh)
iio_push_event(indio_dev,
IIO_EVENT_CODE(IIO_VOLTAGE,
1,
0,
IIO_EV_DIR_RISING,
IIO_EV_TYPE_THRESH,
0, 0, 0),
iio_get_time_ns());
else if (((channels[i] >> 11) & 0xFFF) <=
st->cell_threshlow)
iio_push_event(indio_dev,
IIO_EVENT_CODE(IIO_VOLTAGE,
1,
0,
IIO_EV_DIR_FALLING,
IIO_EV_TYPE_THRESH,
0, 0, 0),
iio_get_time_ns());
} else {
if (((channels[i] >> 11) & 0xFFF) >= st->aux_threshhigh)
iio_push_event(indio_dev,
IIO_UNMOD_EVENT_CODE(IIO_TEMP,
0,
IIO_EV_TYPE_THRESH,
IIO_EV_DIR_RISING),
iio_get_time_ns());
else if (((channels[i] >> 11) & 0xFFF) <=
st->aux_threshlow)
iio_push_event(indio_dev,
IIO_UNMOD_EVENT_CODE(IIO_TEMP,
0,
IIO_EV_TYPE_THRESH,
IIO_EV_DIR_FALLING),
iio_get_time_ns());
}
}
out:
kfree(channels);
return IRQ_HANDLED;
}
static IIO_DEVICE_ATTR_NAMED(in_thresh_low_value,
in_voltage-voltage_thresh_low_value,
S_IRUGO | S_IWUSR,
ad7280_read_channel_config,
ad7280_write_channel_config,
AD7280A_CELL_UNDERVOLTAGE);
static IIO_DEVICE_ATTR_NAMED(in_thresh_high_value,
in_voltage-voltage_thresh_high_value,
S_IRUGO | S_IWUSR,
ad7280_read_channel_config,
ad7280_write_channel_config,
AD7280A_CELL_OVERVOLTAGE);
static IIO_DEVICE_ATTR(in_temp_thresh_low_value,
S_IRUGO | S_IWUSR,
ad7280_read_channel_config,
ad7280_write_channel_config,
AD7280A_AUX_ADC_UNDERVOLTAGE);
static IIO_DEVICE_ATTR(in_temp_thresh_high_value,
S_IRUGO | S_IWUSR,
ad7280_read_channel_config,
ad7280_write_channel_config,
AD7280A_AUX_ADC_OVERVOLTAGE);
static struct attribute *ad7280_event_attributes[] = {
&iio_dev_attr_in_thresh_low_value.dev_attr.attr,
&iio_dev_attr_in_thresh_high_value.dev_attr.attr,
&iio_dev_attr_in_temp_thresh_low_value.dev_attr.attr,
&iio_dev_attr_in_temp_thresh_high_value.dev_attr.attr,
NULL,
};
static struct attribute_group ad7280_event_attrs_group = {
.attrs = ad7280_event_attributes,
};
static int ad7280_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val,
int *val2,
long m)
{
struct ad7280_state *st = iio_priv(indio_dev);
unsigned int scale_uv;
int ret;
switch (m) {
case IIO_CHAN_INFO_RAW:
mutex_lock(&indio_dev->mlock);
if (chan->address == AD7280A_ALL_CELLS)
ret = ad7280_read_all_channels(st, st->scan_cnt, NULL);
else
ret = ad7280_read_channel(st, chan->address >> 8,
chan->address & 0xFF);
mutex_unlock(&indio_dev->mlock);
if (ret < 0)
return ret;
*val = ret;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
if ((chan->address & 0xFF) <= AD7280A_CELL_VOLTAGE_6)
scale_uv = (4000 * 1000) >> AD7280A_BITS;
else
scale_uv = (5000 * 1000) >> AD7280A_BITS;
*val = scale_uv / 1000;
*val2 = (scale_uv % 1000) * 1000;
return IIO_VAL_INT_PLUS_MICRO;
}
return -EINVAL;
}
static const struct iio_info ad7280_info = {
.read_raw = &ad7280_read_raw,
.event_attrs = &ad7280_event_attrs_group,
.attrs = &ad7280_attrs_group,
.driver_module = THIS_MODULE,
};
static const struct ad7280_platform_data ad7793_default_pdata = {
.acquisition_time = AD7280A_ACQ_TIME_400ns,
.conversion_averaging = AD7280A_CONV_AVG_DIS,
.thermistor_term_en = true,
};
static int __devinit ad7280_probe(struct spi_device *spi)
{
const struct ad7280_platform_data *pdata = spi->dev.platform_data;
struct ad7280_state *st;
int ret;
const unsigned short tACQ_ns[4] = {465, 1010, 1460, 1890};
const unsigned short nAVG[4] = {1, 2, 4, 8};
struct iio_dev *indio_dev = iio_device_alloc(sizeof(*st));
if (indio_dev == NULL)
return -ENOMEM;
st = iio_priv(indio_dev);
spi_set_drvdata(spi, indio_dev);
st->spi = spi;
if (!pdata)
pdata = &ad7793_default_pdata;
ad7280_crc8_build_table(st->crc_tab);
st->spi->max_speed_hz = AD7280A_MAX_SPI_CLK_Hz;
st->spi->mode = SPI_MODE_1;
spi_setup(st->spi);
st->ctrl_lb = AD7280A_CTRL_LB_ACQ_TIME(pdata->acquisition_time & 0x3);
st->ctrl_hb = AD7280A_CTRL_HB_CONV_AVG(pdata->conversion_averaging
& 0x3) | (pdata->thermistor_term_en ?
AD7280A_CTRL_LB_THERMISTOR_EN : 0);
ret = ad7280_chain_setup(st);
if (ret < 0)
goto error_free_device;
st->slave_num = ret;
st->scan_cnt = (st->slave_num + 1) * AD7280A_NUM_CH;
st->cell_threshhigh = 0xFF;
st->aux_threshhigh = 0xFF;
/*
* Total Conversion Time = ((tACQ + tCONV) *
* (Number of Conversions per Part)) −
* tACQ + ((N - 1) * tDELAY)
*
* Readback Delay = Total Conversion Time + tWAIT
*/
st->readback_delay_us =
((tACQ_ns[pdata->acquisition_time & 0x3] + 695) *
(AD7280A_NUM_CH * nAVG[pdata->conversion_averaging & 0x3]))
- tACQ_ns[pdata->acquisition_time & 0x3] +
st->slave_num * 250;
/* Convert to usecs */
st->readback_delay_us = DIV_ROUND_UP(st->readback_delay_us, 1000);
st->readback_delay_us += 5; /* Add tWAIT */
indio_dev->name = spi_get_device_id(spi)->name;
indio_dev->dev.parent = &spi->dev;
indio_dev->modes = INDIO_DIRECT_MODE;
ret = ad7280_channel_init(st);
if (ret < 0)
goto error_free_device;
indio_dev->num_channels = ret;
indio_dev->channels = st->channels;
indio_dev->info = &ad7280_info;
ret = ad7280_attr_init(st);
if (ret < 0)
goto error_free_channels;
ret = iio_device_register(indio_dev);
if (ret)
goto error_free_attr;
if (spi->irq > 0) {
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
AD7280A_ALERT, 1,
AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN);
if (ret)
goto error_unregister;
ret = ad7280_write(st, AD7280A_DEVADDR(st->slave_num),
AD7280A_ALERT, 0,
AD7280A_ALERT_GEN_STATIC_HIGH |
(pdata->chain_last_alert_ignore & 0xF));
if (ret)
goto error_unregister;
ret = request_threaded_irq(spi->irq,
NULL,
ad7280_event_handler,
IRQF_TRIGGER_FALLING |
IRQF_ONESHOT,
indio_dev->name,
indio_dev);
if (ret)
goto error_unregister;
}
return 0;
error_unregister:
iio_device_unregister(indio_dev);
error_free_attr:
kfree(st->iio_attr);
error_free_channels:
kfree(st->channels);
error_free_device:
iio_device_free(indio_dev);
return ret;
}
static int __devexit ad7280_remove(struct spi_device *spi)
{
struct iio_dev *indio_dev = spi_get_drvdata(spi);
struct ad7280_state *st = iio_priv(indio_dev);
if (spi->irq > 0)
free_irq(spi->irq, indio_dev);
iio_device_unregister(indio_dev);
ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
AD7280A_CTRL_HB_PWRDN_SW | st->ctrl_hb);
kfree(st->channels);
kfree(st->iio_attr);
iio_device_free(indio_dev);
return 0;
}
static const struct spi_device_id ad7280_id[] = {
{"ad7280a", 0},
{}
};
MODULE_DEVICE_TABLE(spi, ad7280_id);
static struct spi_driver ad7280_driver = {
.driver = {
.name = "ad7280",
.owner = THIS_MODULE,
},
.probe = ad7280_probe,
.remove = __devexit_p(ad7280_remove),
.id_table = ad7280_id,
};
module_spi_driver(ad7280_driver);
MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
MODULE_DESCRIPTION("Analog Devices AD7280A");
MODULE_LICENSE("GPL v2");