// SPDX-License-Identifier: GPL-2.0
/*
* AD7280A Lithium Ion Battery Monitoring System
*
* Copyright 2011 Analog Devices Inc.
*/
#include <linux/bitfield.h>
#include <linux/bits.h>
#include <linux/crc8.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/spi/spi.h>
#include <linux/iio/events.h>
#include <linux/iio/iio.h>
/* Registers */
#define AD7280A_CELL_VOLTAGE_1_REG 0x0 /* D11 to D0, Read only */
#define AD7280A_CELL_VOLTAGE_2_REG 0x1 /* D11 to D0, Read only */
#define AD7280A_CELL_VOLTAGE_3_REG 0x2 /* D11 to D0, Read only */
#define AD7280A_CELL_VOLTAGE_4_REG 0x3 /* D11 to D0, Read only */
#define AD7280A_CELL_VOLTAGE_5_REG 0x4 /* D11 to D0, Read only */
#define AD7280A_CELL_VOLTAGE_6_REG 0x5 /* D11 to D0, Read only */
#define AD7280A_AUX_ADC_1_REG 0x6 /* D11 to D0, Read only */
#define AD7280A_AUX_ADC_2_REG 0x7 /* D11 to D0, Read only */
#define AD7280A_AUX_ADC_3_REG 0x8 /* D11 to D0, Read only */
#define AD7280A_AUX_ADC_4_REG 0x9 /* D11 to D0, Read only */
#define AD7280A_AUX_ADC_5_REG 0xA /* D11 to D0, Read only */
#define AD7280A_AUX_ADC_6_REG 0xB /* D11 to D0, Read only */
#define AD7280A_SELF_TEST_REG 0xC /* D11 to D0, Read only */
#define AD7280A_CTRL_HB_REG 0xD /* D15 to D8, Read/write */
#define AD7280A_CTRL_HB_CONV_INPUT_MSK GENMASK(7, 6)
#define AD7280A_CTRL_HB_CONV_INPUT_ALL 0
#define AD7280A_CTRL_HB_CONV_INPUT_6CELL_AUX1_3_5 1
#define AD7280A_CTRL_HB_CONV_INPUT_6CELL 2
#define AD7280A_CTRL_HB_CONV_INPUT_SELF_TEST 3
#define AD7280A_CTRL_HB_CONV_RREAD_MSK GENMASK(5, 4)
#define AD7280A_CTRL_HB_CONV_RREAD_ALL 0
#define AD7280A_CTRL_HB_CONV_RREAD_6CELL_AUX1_3_5 1
#define AD7280A_CTRL_HB_CONV_RREAD_6CELL 2
#define AD7280A_CTRL_HB_CONV_RREAD_NO 3
#define AD7280A_CTRL_HB_CONV_START_MSK BIT(3)
#define AD7280A_CTRL_HB_CONV_START_CNVST 0
#define AD7280A_CTRL_HB_CONV_START_CS 1
#define AD7280A_CTRL_HB_CONV_AVG_MSK GENMASK(2, 1)
#define AD7280A_CTRL_HB_CONV_AVG_DIS 0
#define AD7280A_CTRL_HB_CONV_AVG_2 1
#define AD7280A_CTRL_HB_CONV_AVG_4 2
#define AD7280A_CTRL_HB_CONV_AVG_8 3
#define AD7280A_CTRL_HB_PWRDN_SW BIT(0)
#define AD7280A_CTRL_LB_REG 0xE /* D7 to D0, Read/write */
#define AD7280A_CTRL_LB_SWRST_MSK BIT(7)
#define AD7280A_CTRL_LB_ACQ_TIME_MSK GENMASK(6, 5)
#define AD7280A_CTRL_LB_ACQ_TIME_400ns 0
#define AD7280A_CTRL_LB_ACQ_TIME_800ns 1
#define AD7280A_CTRL_LB_ACQ_TIME_1200ns 2
#define AD7280A_CTRL_LB_ACQ_TIME_1600ns 3
#define AD7280A_CTRL_LB_MUST_SET BIT(4)
#define AD7280A_CTRL_LB_THERMISTOR_MSK BIT(3)
#define AD7280A_CTRL_LB_LOCK_DEV_ADDR_MSK BIT(2)
#define AD7280A_CTRL_LB_INC_DEV_ADDR_MSK BIT(1)
#define AD7280A_CTRL_LB_DAISY_CHAIN_RB_MSK BIT(0)
#define AD7280A_CELL_OVERVOLTAGE_REG 0xF /* D7 to D0, Read/write */
#define AD7280A_CELL_UNDERVOLTAGE_REG 0x10 /* D7 to D0, Read/write */
#define AD7280A_AUX_ADC_OVERVOLTAGE_REG 0x11 /* D7 to D0, Read/write */
#define AD7280A_AUX_ADC_UNDERVOLTAGE_REG 0x12 /* D7 to D0, Read/write */
#define AD7280A_ALERT_REG 0x13 /* D7 to D0, Read/write */
#define AD7280A_ALERT_REMOVE_MSK GENMASK(3, 0)
#define AD7280A_ALERT_REMOVE_AUX5 BIT(0)
#define AD7280A_ALERT_REMOVE_AUX3_AUX5 BIT(1)
#define AD7280A_ALERT_REMOVE_VIN5 BIT(2)
#define AD7280A_ALERT_REMOVE_VIN4_VIN5 BIT(3)
#define AD7280A_ALERT_GEN_STATIC_HIGH BIT(6)
#define AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN (BIT(7) | BIT(6))
#define AD7280A_CELL_BALANCE_REG 0x14 /* D7 to D0, Read/write */
#define AD7280A_CELL_BALANCE_CHAN_BITMAP_MSK GENMASK(7, 2)
#define AD7280A_CB1_TIMER_REG 0x15 /* D7 to D0, Read/write */
#define AD7280A_CB_TIMER_VAL_MSK GENMASK(7, 3)
#define AD7280A_CB2_TIMER_REG 0x16 /* D7 to D0, Read/write */
#define AD7280A_CB3_TIMER_REG 0x17 /* D7 to D0, Read/write */
#define AD7280A_CB4_TIMER_REG 0x18 /* D7 to D0, Read/write */
#define AD7280A_CB5_TIMER_REG 0x19 /* D7 to D0, Read/write */
#define AD7280A_CB6_TIMER_REG 0x1A /* D7 to D0, Read/write */
#define AD7280A_PD_TIMER_REG 0x1B /* D7 to D0, Read/write */
#define AD7280A_READ_REG 0x1C /* D7 to D0, Read/write */
#define AD7280A_READ_ADDR_MSK GENMASK(7, 2)
#define AD7280A_CNVST_CTRL_REG 0x1D /* D7 to D0, Read/write */
/* Transfer fields */
#define AD7280A_TRANS_WRITE_DEVADDR_MSK GENMASK(31, 27)
#define AD7280A_TRANS_WRITE_ADDR_MSK GENMASK(26, 21)
#define AD7280A_TRANS_WRITE_VAL_MSK GENMASK(20, 13)
#define AD7280A_TRANS_WRITE_ALL_MSK BIT(12)
#define AD7280A_TRANS_WRITE_CRC_MSK GENMASK(10, 3)
#define AD7280A_TRANS_WRITE_RES_PATTERN 0x2
/* Layouts differ for channel vs other registers */
#define AD7280A_TRANS_READ_DEVADDR_MSK GENMASK(31, 27)
#define AD7280A_TRANS_READ_CONV_CHANADDR_MSK GENMASK(26, 23)
#define AD7280A_TRANS_READ_CONV_DATA_MSK GENMASK(22, 11)
#define AD7280A_TRANS_READ_REG_REGADDR_MSK GENMASK(26, 21)
#define AD7280A_TRANS_READ_REG_DATA_MSK GENMASK(20, 13)
#define AD7280A_TRANS_READ_WRITE_ACK_MSK BIT(10)
#define AD7280A_TRANS_READ_CRC_MSK GENMASK(9, 2)
/* Magic value used to indicate this special case */
#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_REG - \
AD7280A_CELL_VOLTAGE_1_REG + 1)
#define AD7280A_CALC_VOLTAGE_CHAN_NUM(d, c) (((d) * AD7280A_CELLS_PER_DEV) + \
(c))
#define AD7280A_CALC_TEMP_CHAN_NUM(d, c) (((d) * AD7280A_CELLS_PER_DEV) + \
(c) - AD7280A_CELLS_PER_DEV)
#define AD7280A_DEVADDR_MASTER 0
#define AD7280A_DEVADDR_ALL 0x1F
static const unsigned short ad7280a_n_avg[4] = {1, 2, 4, 8};
static const unsigned short ad7280a_t_acq_ns[4] = {470, 1030, 1510, 1945};
/* 5-bit device address is sent LSB first */
static unsigned int ad7280a_devaddr(unsigned int addr)
{
return ((addr & 0x1) << 4) |
((addr & 0x2) << 2) |
(addr & 0x4) |
((addr & 0x8) >> 2) |
((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
struct ad7280_state {
struct spi_device *spi;
struct iio_chan_spec *channels;
unsigned int chain_last_alert_ignore;
bool thermistor_term_en;
int slave_num;
int scan_cnt;
int readback_delay_us;
unsigned char crc_tab[CRC8_TABLE_SIZE];
u8 oversampling_ratio;
u8 acquisition_time;
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];
struct mutex lock; /* protect sensor state */
__be32 tx __aligned(IIO_DMA_MINALIGN);
__be32 rx;
};
static unsigned char ad7280_calc_crc8(unsigned char *crc_tab, unsigned int 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 int 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..30us however depending on
* the number of devices in the daisy chain, 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
usleep_range(250, 500);
}
static int __ad7280_read32(struct ad7280_state *st, unsigned int *val)
{
int ret;
struct spi_transfer t = {
.tx_buf = &st->tx,
.rx_buf = &st->rx,
.len = sizeof(st->tx),
};
st->tx = cpu_to_be32(AD7280A_READ_TXVAL);
ret = spi_sync_transfer(st->spi, &t, 1);
if (ret)
return ret;
*val = be32_to_cpu(st->rx);
return 0;
}
static int ad7280_write(struct ad7280_state *st, unsigned int devaddr,
unsigned int addr, bool all, unsigned int val)
{
unsigned int reg = FIELD_PREP(AD7280A_TRANS_WRITE_DEVADDR_MSK, devaddr) |
FIELD_PREP(AD7280A_TRANS_WRITE_ADDR_MSK, addr) |
FIELD_PREP(AD7280A_TRANS_WRITE_VAL_MSK, val) |
FIELD_PREP(AD7280A_TRANS_WRITE_ALL_MSK, all);
reg |= FIELD_PREP(AD7280A_TRANS_WRITE_CRC_MSK,
ad7280_calc_crc8(st->crc_tab, reg >> 11));
/* Reserved b010 pattern not included crc calc */
reg |= AD7280A_TRANS_WRITE_RES_PATTERN;
st->tx = cpu_to_be32(reg);
return spi_write(st->spi, &st->tx, sizeof(st->tx));
}
static int ad7280_read_reg(struct ad7280_state *st, unsigned int devaddr,
unsigned int addr)
{
int ret;
unsigned int tmp;
/* turns off the read operation on all parts */
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,
FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,
AD7280A_CTRL_HB_CONV_INPUT_ALL) |
FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,
AD7280A_CTRL_HB_CONV_RREAD_NO) |
FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,
st->oversampling_ratio));
if (ret)
return ret;
/* turns on the read operation on the addressed part */
ret = ad7280_write(st, devaddr, AD7280A_CTRL_HB_REG, 0,
FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,
AD7280A_CTRL_HB_CONV_INPUT_ALL) |
FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,
AD7280A_CTRL_HB_CONV_RREAD_ALL) |
FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,
st->oversampling_ratio));
if (ret)
return ret;
/* Set register address on the part to be read from */
ret = ad7280_write(st, devaddr, AD7280A_READ_REG, 0,
FIELD_PREP(AD7280A_READ_ADDR_MSK, addr));
if (ret)
return ret;
ret = __ad7280_read32(st, &tmp);
if (ret)
return ret;
if (ad7280_check_crc(st, tmp))
return -EIO;
if ((FIELD_GET(AD7280A_TRANS_READ_DEVADDR_MSK, tmp) != devaddr) ||
(FIELD_GET(AD7280A_TRANS_READ_REG_REGADDR_MSK, tmp) != addr))
return -EFAULT;
return FIELD_GET(AD7280A_TRANS_READ_REG_DATA_MSK, tmp);
}
static int ad7280_read_channel(struct ad7280_state *st, unsigned int devaddr,
unsigned int addr)
{
int ret;
unsigned int tmp;
ret = ad7280_write(st, devaddr, AD7280A_READ_REG, 0,
FIELD_PREP(AD7280A_READ_ADDR_MSK, addr));
if (ret)
return ret;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,
FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,
AD7280A_CTRL_HB_CONV_INPUT_ALL) |
FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,
AD7280A_CTRL_HB_CONV_RREAD_NO) |
FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,
st->oversampling_ratio));
if (ret)
return ret;
ret = ad7280_write(st, devaddr, AD7280A_CTRL_HB_REG, 0,
FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,
AD7280A_CTRL_HB_CONV_INPUT_ALL) |
FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,
AD7280A_CTRL_HB_CONV_RREAD_ALL) |
FIELD_PREP(AD7280A_CTRL_HB_CONV_START_MSK,
AD7280A_CTRL_HB_CONV_START_CS) |
FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,
st->oversampling_ratio));
if (ret)
return ret;
ad7280_delay(st);
ret = __ad7280_read32(st, &tmp);
if (ret)
return ret;
if (ad7280_check_crc(st, tmp))
return -EIO;
if ((FIELD_GET(AD7280A_TRANS_READ_DEVADDR_MSK, tmp) != devaddr) ||
(FIELD_GET(AD7280A_TRANS_READ_CONV_CHANADDR_MSK, tmp) != addr))
return -EFAULT;
return FIELD_GET(AD7280A_TRANS_READ_CONV_DATA_MSK, tmp);
}
static int ad7280_read_all_channels(struct ad7280_state *st, unsigned int cnt,
unsigned int *array)
{
int i, ret;
unsigned int tmp, sum = 0;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ_REG, 1,
AD7280A_CELL_VOLTAGE_1_REG << 2);
if (ret)
return ret;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,
FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,
AD7280A_CTRL_HB_CONV_INPUT_ALL) |
FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,
AD7280A_CTRL_HB_CONV_RREAD_ALL) |
FIELD_PREP(AD7280A_CTRL_HB_CONV_START_MSK,
AD7280A_CTRL_HB_CONV_START_CS) |
FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,
st->oversampling_ratio));
if (ret)
return ret;
ad7280_delay(st);
for (i = 0; i < cnt; i++) {
ret = __ad7280_read32(st, &tmp);
if (ret)
return ret;
if (ad7280_check_crc(st, tmp))
return -EIO;
if (array)
array[i] = tmp;
/* only sum cell voltages */
if (FIELD_GET(AD7280A_TRANS_READ_CONV_CHANADDR_MSK, tmp) <=
AD7280A_CELL_VOLTAGE_6_REG)
sum += FIELD_GET(AD7280A_TRANS_READ_CONV_DATA_MSK, tmp);
}
return sum;
}
static void ad7280_sw_power_down(void *data)
{
struct ad7280_state *st = data;
ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,
AD7280A_CTRL_HB_PWRDN_SW |
FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK, st->oversampling_ratio));
}
static int ad7280_chain_setup(struct ad7280_state *st)
{
unsigned int val, n;
int ret;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_LB_REG, 1,
FIELD_PREP(AD7280A_CTRL_LB_DAISY_CHAIN_RB_MSK, 1) |
FIELD_PREP(AD7280A_CTRL_LB_LOCK_DEV_ADDR_MSK, 1) |
AD7280A_CTRL_LB_MUST_SET |
FIELD_PREP(AD7280A_CTRL_LB_SWRST_MSK, 1) |
st->ctrl_lb);
if (ret)
return ret;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_LB_REG, 1,
FIELD_PREP(AD7280A_CTRL_LB_DAISY_CHAIN_RB_MSK, 1) |
FIELD_PREP(AD7280A_CTRL_LB_LOCK_DEV_ADDR_MSK, 1) |
AD7280A_CTRL_LB_MUST_SET |
FIELD_PREP(AD7280A_CTRL_LB_SWRST_MSK, 0) |
st->ctrl_lb);
if (ret)
goto error_power_down;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ_REG, 1,
FIELD_PREP(AD7280A_READ_ADDR_MSK, AD7280A_CTRL_LB_REG));
if (ret)
goto error_power_down;
for (n = 0; n <= AD7280A_MAX_CHAIN; n++) {
ret = __ad7280_read32(st, &val);
if (ret)
goto error_power_down;
if (val == 0)
return n - 1;
if (ad7280_check_crc(st, val)) {
ret = -EIO;
goto error_power_down;
}
if (n != ad7280a_devaddr(FIELD_GET(AD7280A_TRANS_READ_DEVADDR_MSK, val))) {
ret = -EIO;
goto error_power_down;
}
}
ret = -EFAULT;
error_power_down:
ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,
AD7280A_CTRL_HB_PWRDN_SW |
FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK, st->oversampling_ratio));
return ret;
}
static ssize_t ad7280_show_balance_sw(struct iio_dev *indio_dev,
uintptr_t private,
const struct iio_chan_spec *chan, char *buf)
{
struct ad7280_state *st = iio_priv(indio_dev);
return sysfs_emit(buf, "%d\n",
!!(st->cb_mask[chan->address >> 8] &
BIT(chan->address & 0xFF)));
}
static ssize_t ad7280_store_balance_sw(struct iio_dev *indio_dev,
uintptr_t private,
const struct iio_chan_spec *chan,
const char *buf, size_t len)
{
struct ad7280_state *st = iio_priv(indio_dev);
unsigned int devaddr, ch;
bool readin;
int ret;
ret = kstrtobool(buf, &readin);
if (ret)
return ret;
devaddr = chan->address >> 8;
ch = chan->address & 0xFF;
mutex_lock(&st->lock);
if (readin)
st->cb_mask[devaddr] |= BIT(ch);
else
st->cb_mask[devaddr] &= ~BIT(ch);
ret = ad7280_write(st, devaddr, AD7280A_CELL_BALANCE_REG, 0,
FIELD_PREP(AD7280A_CELL_BALANCE_CHAN_BITMAP_MSK,
st->cb_mask[devaddr]));
mutex_unlock(&st->lock);
return ret ? ret : len;
}
static ssize_t ad7280_show_balance_timer(struct iio_dev *indio_dev,
uintptr_t private,
const struct iio_chan_spec *chan,
char *buf)
{
struct ad7280_state *st = iio_priv(indio_dev);
unsigned int msecs;
int ret;
mutex_lock(&st->lock);
ret = ad7280_read_reg(st, chan->address >> 8,
(chan->address & 0xFF) + AD7280A_CB1_TIMER_REG);
mutex_unlock(&st->lock);
if (ret < 0)
return ret;
msecs = FIELD_GET(AD7280A_CB_TIMER_VAL_MSK, ret) * 71500;
return sysfs_emit(buf, "%u.%u\n", msecs / 1000, msecs % 1000);
}
static ssize_t ad7280_store_balance_timer(struct iio_dev *indio_dev,
uintptr_t private,
const struct iio_chan_spec *chan,
const char *buf, size_t len)
{
struct ad7280_state *st = iio_priv(indio_dev);
int val, val2;
int ret;
ret = iio_str_to_fixpoint(buf, 1000, &val, &val2);
if (ret)
return ret;
val = val * 1000 + val2;
val /= 71500;
if (val > 31)
return -EINVAL;
mutex_lock(&st->lock);
ret = ad7280_write(st, chan->address >> 8,
(chan->address & 0xFF) + AD7280A_CB1_TIMER_REG, 0,
FIELD_PREP(AD7280A_CB_TIMER_VAL_MSK, val));
mutex_unlock(&st->lock);
return ret ? ret : len;
}
static const struct iio_chan_spec_ext_info ad7280_cell_ext_info[] = {
{
.name = "balance_switch_en",
.read = ad7280_show_balance_sw,
.write = ad7280_store_balance_sw,
.shared = IIO_SEPARATE,
}, {
.name = "balance_switch_timer",
.read = ad7280_show_balance_timer,
.write = ad7280_store_balance_timer,
.shared = IIO_SEPARATE,
},
{}
};
static const struct iio_event_spec ad7280_events[] = {
{
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_RISING,
.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE),
}, {
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_FALLING,
.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE),
},
};
static void ad7280_voltage_channel_init(struct iio_chan_spec *chan, int i,
bool irq_present)
{
chan->type = IIO_VOLTAGE;
chan->differential = 1;
chan->channel = i;
chan->channel2 = chan->channel + 1;
if (irq_present) {
chan->event_spec = ad7280_events;
chan->num_event_specs = ARRAY_SIZE(ad7280_events);
}
chan->ext_info = ad7280_cell_ext_info;
}
static void ad7280_temp_channel_init(struct iio_chan_spec *chan, int i,
bool irq_present)
{
chan->type = IIO_TEMP;
chan->channel = i;
if (irq_present) {
chan->event_spec = ad7280_events;
chan->num_event_specs = ARRAY_SIZE(ad7280_events);
}
}
static void ad7280_common_fields_init(struct iio_chan_spec *chan, int addr,
int cnt)
{
chan->indexed = 1;
chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);
chan->info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO);
chan->address = addr;
chan->scan_index = cnt;
chan->scan_type.sign = 'u';
chan->scan_type.realbits = 12;
chan->scan_type.storagebits = 32;
}
static void ad7280_total_voltage_channel_init(struct iio_chan_spec *chan,
int cnt, int dev)
{
chan->type = IIO_VOLTAGE;
chan->differential = 1;
chan->channel = 0;
chan->channel2 = dev * AD7280A_CELLS_PER_DEV;
chan->address = AD7280A_ALL_CELLS;
chan->indexed = 1;
chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);
chan->scan_index = cnt;
chan->scan_type.sign = 'u';
chan->scan_type.realbits = 32;
chan->scan_type.storagebits = 32;
}
static void ad7280_init_dev_channels(struct ad7280_state *st, int dev, int *cnt,
bool irq_present)
{
int addr, ch, i;
struct iio_chan_spec *chan;
for (ch = AD7280A_CELL_VOLTAGE_1_REG; ch <= AD7280A_AUX_ADC_6_REG; ch++) {
chan = &st->channels[*cnt];
if (ch < AD7280A_AUX_ADC_1_REG) {
i = AD7280A_CALC_VOLTAGE_CHAN_NUM(dev, ch);
ad7280_voltage_channel_init(chan, i, irq_present);
} else {
i = AD7280A_CALC_TEMP_CHAN_NUM(dev, ch);
ad7280_temp_channel_init(chan, i, irq_present);
}
addr = ad7280a_devaddr(dev) << 8 | ch;
ad7280_common_fields_init(chan, addr, *cnt);
(*cnt)++;
}
}
static int ad7280_channel_init(struct ad7280_state *st, bool irq_present)
{
int dev, cnt = 0;
st->channels = devm_kcalloc(&st->spi->dev, (st->slave_num + 1) * 12 + 1,
sizeof(*st->channels), GFP_KERNEL);
if (!st->channels)
return -ENOMEM;
for (dev = 0; dev <= st->slave_num; dev++)
ad7280_init_dev_channels(st, dev, &cnt, irq_present);
ad7280_total_voltage_channel_init(&st->channels[cnt], cnt, dev);
return cnt + 1;
}
static int ad7280a_read_thresh(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir,
enum iio_event_info info, int *val, int *val2)
{
struct ad7280_state *st = iio_priv(indio_dev);
switch (chan->type) {
case IIO_VOLTAGE:
switch (dir) {
case IIO_EV_DIR_RISING:
*val = 1000 + (st->cell_threshhigh * 1568L) / 100;
return IIO_VAL_INT;
case IIO_EV_DIR_FALLING:
*val = 1000 + (st->cell_threshlow * 1568L) / 100;
return IIO_VAL_INT;
default:
return -EINVAL;
}
break;
case IIO_TEMP:
switch (dir) {
case IIO_EV_DIR_RISING:
*val = ((st->aux_threshhigh) * 196L) / 10;
return IIO_VAL_INT;
case IIO_EV_DIR_FALLING:
*val = (st->aux_threshlow * 196L) / 10;
return IIO_VAL_INT;
default:
return -EINVAL;
}
break;
default:
return -EINVAL;
}
}
static int ad7280a_write_thresh(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir,
enum iio_event_info info,
int val, int val2)
{
struct ad7280_state *st = iio_priv(indio_dev);
unsigned int addr;
long value;
int ret;
if (val2 != 0)
return -EINVAL;
mutex_lock(&st->lock);
switch (chan->type) {
case IIO_VOLTAGE:
value = ((val - 1000) * 100) / 1568; /* LSB 15.68mV */
value = clamp(value, 0L, 0xFFL);
switch (dir) {
case IIO_EV_DIR_RISING:
addr = AD7280A_CELL_OVERVOLTAGE_REG;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr,
1, value);
if (ret)
break;
st->cell_threshhigh = value;
break;
case IIO_EV_DIR_FALLING:
addr = AD7280A_CELL_UNDERVOLTAGE_REG;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr,
1, value);
if (ret)
break;
st->cell_threshlow = value;
break;
default:
ret = -EINVAL;
goto err_unlock;
}
break;
case IIO_TEMP:
value = (val * 10) / 196; /* LSB 19.6mV */
value = clamp(value, 0L, 0xFFL);
switch (dir) {
case IIO_EV_DIR_RISING:
addr = AD7280A_AUX_ADC_OVERVOLTAGE_REG;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr,
1, value);
if (ret)
break;
st->aux_threshhigh = value;
break;
case IIO_EV_DIR_FALLING:
addr = AD7280A_AUX_ADC_UNDERVOLTAGE_REG;
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr,
1, value);
if (ret)
break;
st->aux_threshlow = value;
break;
default:
ret = -EINVAL;
goto err_unlock;
}
break;
default:
ret = -EINVAL;
goto err_unlock;
}
err_unlock:
mutex_unlock(&st->lock);
return ret;
}
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 int *channels;
int i, ret;
channels = kcalloc(st->scan_cnt, sizeof(*channels), GFP_KERNEL);
if (!channels)
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++) {
unsigned int val;
val = FIELD_GET(AD7280A_TRANS_READ_CONV_DATA_MSK, channels[i]);
if (FIELD_GET(AD7280A_TRANS_READ_CONV_CHANADDR_MSK, channels[i]) <=
AD7280A_CELL_VOLTAGE_6_REG) {
if (val >= st->cell_threshhigh) {
u64 tmp = IIO_EVENT_CODE(IIO_VOLTAGE, 1, 0,
IIO_EV_DIR_RISING,
IIO_EV_TYPE_THRESH,
0, 0, 0);
iio_push_event(indio_dev, tmp,
iio_get_time_ns(indio_dev));
} else if (val <= st->cell_threshlow) {
u64 tmp = IIO_EVENT_CODE(IIO_VOLTAGE, 1, 0,
IIO_EV_DIR_FALLING,
IIO_EV_TYPE_THRESH,
0, 0, 0);
iio_push_event(indio_dev, tmp,
iio_get_time_ns(indio_dev));
}
} else {
if (val >= st->aux_threshhigh) {
u64 tmp = IIO_UNMOD_EVENT_CODE(IIO_TEMP, 0,
IIO_EV_TYPE_THRESH,
IIO_EV_DIR_RISING);
iio_push_event(indio_dev, tmp,
iio_get_time_ns(indio_dev));
} else if (val <= st->aux_threshlow) {
u64 tmp = IIO_UNMOD_EVENT_CODE(IIO_TEMP, 0,
IIO_EV_TYPE_THRESH,
IIO_EV_DIR_FALLING);
iio_push_event(indio_dev, tmp,
iio_get_time_ns(indio_dev));
}
}
}
out:
kfree(channels);
return IRQ_HANDLED;
}
static void ad7280_update_delay(struct ad7280_state *st)
{
/*
* Total Conversion Time = ((tACQ + tCONV) *
* (Number of Conversions per Part)) −
* tACQ + ((N - 1) * tDELAY)
*
* Readback Delay = Total Conversion Time + tWAIT
*/
st->readback_delay_us =
((ad7280a_t_acq_ns[st->acquisition_time & 0x3] + 720) *
(AD7280A_NUM_CH * ad7280a_n_avg[st->oversampling_ratio & 0x3])) -
ad7280a_t_acq_ns[st->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 */
}
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);
int ret;
switch (m) {
case IIO_CHAN_INFO_RAW:
mutex_lock(&st->lock);
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(&st->lock);
if (ret < 0)
return ret;
*val = ret;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
if ((chan->address & 0xFF) <= AD7280A_CELL_VOLTAGE_6_REG)
*val = 4000;
else
*val = 5000;
*val2 = AD7280A_BITS;
return IIO_VAL_FRACTIONAL_LOG2;
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
*val = ad7280a_n_avg[st->oversampling_ratio];
return IIO_VAL_INT;
}
return -EINVAL;
}
static int ad7280_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct ad7280_state *st = iio_priv(indio_dev);
int i;
switch (mask) {
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
if (val2 != 0)
return -EINVAL;
for (i = 0; i < ARRAY_SIZE(ad7280a_n_avg); i++) {
if (val == ad7280a_n_avg[i]) {
st->oversampling_ratio = i;
ad7280_update_delay(st);
return 0;
}
}
return -EINVAL;
default:
return -EINVAL;
}
}
static const struct iio_info ad7280_info = {
.read_raw = ad7280_read_raw,
.write_raw = ad7280_write_raw,
.read_event_value = &ad7280a_read_thresh,
.write_event_value = &ad7280a_write_thresh,
};
static const struct iio_info ad7280_info_no_irq = {
.read_raw = ad7280_read_raw,
.write_raw = ad7280_write_raw,
};
static int ad7280_probe(struct spi_device *spi)
{
struct device *dev = &spi->dev;
struct ad7280_state *st;
int ret;
struct iio_dev *indio_dev;
indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
if (!indio_dev)
return -ENOMEM;
st = iio_priv(indio_dev);
spi_set_drvdata(spi, indio_dev);
st->spi = spi;
mutex_init(&st->lock);
st->thermistor_term_en =
device_property_read_bool(dev, "adi,thermistor-termination");
if (device_property_present(dev, "adi,acquisition-time-ns")) {
u32 val;
ret = device_property_read_u32(dev, "adi,acquisition-time-ns", &val);
if (ret)
return ret;
switch (val) {
case 400:
st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_400ns;
break;
case 800:
st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_800ns;
break;
case 1200:
st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_1200ns;
break;
case 1600:
st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_1600ns;
break;
default:
dev_err(dev, "Firmware provided acquisition time is invalid\n");
return -EINVAL;
}
} else {
st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_400ns;
}
/* Alert masks are intended for when particular inputs are not wired up */
if (device_property_present(dev, "adi,voltage-alert-last-chan")) {
u32 val;
ret = device_property_read_u32(dev, "adi,voltage-alert-last-chan", &val);
if (ret)
return ret;
switch (val) {
case 3:
st->chain_last_alert_ignore |= AD7280A_ALERT_REMOVE_VIN4_VIN5;
break;
case 4:
st->chain_last_alert_ignore |= AD7280A_ALERT_REMOVE_VIN5;
break;
case 5:
break;
default:
dev_err(dev,
"Firmware provided last voltage alert channel invalid\n");
break;
}
}
crc8_populate_msb(st->crc_tab, POLYNOM);
st->spi->max_speed_hz = AD7280A_MAX_SPI_CLK_HZ;
st->spi->mode = SPI_MODE_1;
spi_setup(st->spi);
st->ctrl_lb = FIELD_PREP(AD7280A_CTRL_LB_ACQ_TIME_MSK, st->acquisition_time) |
FIELD_PREP(AD7280A_CTRL_LB_THERMISTOR_MSK, st->thermistor_term_en);
st->oversampling_ratio = 0; /* No oversampling */
ret = ad7280_chain_setup(st);
if (ret < 0)
return ret;
st->slave_num = ret;
st->scan_cnt = (st->slave_num + 1) * AD7280A_NUM_CH;
st->cell_threshhigh = 0xFF;
st->aux_threshhigh = 0xFF;
ret = devm_add_action_or_reset(dev, ad7280_sw_power_down, st);
if (ret)
return ret;
ad7280_update_delay(st);
indio_dev->name = spi_get_device_id(spi)->name;
indio_dev->modes = INDIO_DIRECT_MODE;
ret = ad7280_channel_init(st, spi->irq > 0);
if (ret < 0)
return ret;
indio_dev->num_channels = ret;
indio_dev->channels = st->channels;
if (spi->irq > 0) {
ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
AD7280A_ALERT_REG, 1,
AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN);
if (ret)
return ret;
ret = ad7280_write(st, ad7280a_devaddr(st->slave_num),
AD7280A_ALERT_REG, 0,
AD7280A_ALERT_GEN_STATIC_HIGH |
FIELD_PREP(AD7280A_ALERT_REMOVE_MSK,
st->chain_last_alert_ignore));
if (ret)
return ret;
ret = devm_request_threaded_irq(dev, spi->irq,
NULL,
ad7280_event_handler,
IRQF_TRIGGER_FALLING |
IRQF_ONESHOT,
indio_dev->name,
indio_dev);
if (ret)
return ret;
indio_dev->info = &ad7280_info;
} else {
indio_dev->info = &ad7280_info_no_irq;
}
return devm_iio_device_register(dev, indio_dev);
}
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",
},
.probe = ad7280_probe,
.id_table = ad7280_id,
};
module_spi_driver(ad7280_driver);
MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
MODULE_DESCRIPTION("Analog Devices AD7280A");
MODULE_LICENSE("GPL v2");
