mirror of
https://github.com/torvalds/linux.git
synced 2024-11-10 14:11:52 +00:00
iio: add MCP4728 I2C DAC driver
MCP4728 is a 12-bit quad channel DAC with I2C interface. support for: * per-channel gain * per-channel power state * per-channel power down mode control * per-channel vref selection internal/vdd * store current state to on-chip EEPROM Signed-off-by: Andrea Collamati <andrea.collamati@gmail.com> Link: https://lore.kernel.org/r/a0933003ed3c855f9d80d6ce0a40add2b6f0ba36.1691066050.git.andrea.collamati@gmail.com Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Andrea Collamati
Jonathan Cameron
parent
74d4cd7a91
commit
7b24a034ad
@ -389,6 +389,17 @@ config MCP4725
|
||||
To compile this driver as a module, choose M here: the module
|
||||
will be called mcp4725.
|
||||
|
||||
config MCP4728
|
||||
tristate "MCP4728 DAC driver"
|
||||
depends on I2C
|
||||
help
|
||||
Say Y here if you want to build a driver for the Microchip
|
||||
MCP4728 quad channel, 12-bit digital-to-analog converter (DAC)
|
||||
with I2C interface.
|
||||
|
||||
To compile this driver as a module, choose M here: the module
|
||||
will be called mcp4728.
|
||||
|
||||
config MCP4922
|
||||
tristate "MCP4902, MCP4912, MCP4922 DAC driver"
|
||||
depends on SPI
|
||||
|
||||
@ -41,6 +41,7 @@ obj-$(CONFIG_MAX517) += max517.o
|
||||
obj-$(CONFIG_MAX5522) += max5522.o
|
||||
obj-$(CONFIG_MAX5821) += max5821.o
|
||||
obj-$(CONFIG_MCP4725) += mcp4725.o
|
||||
obj-$(CONFIG_MCP4728) += mcp4728.o
|
||||
obj-$(CONFIG_MCP4922) += mcp4922.o
|
||||
obj-$(CONFIG_STM32_DAC_CORE) += stm32-dac-core.o
|
||||
obj-$(CONFIG_STM32_DAC) += stm32-dac.o
|
||||
|
||||
618
drivers/iio/dac/mcp4728.c
Normal file
618
drivers/iio/dac/mcp4728.c
Normal file
@ -0,0 +1,618 @@
|
||||
// SPDX-License-Identifier: GPL-2.0-only
|
||||
/*
|
||||
* Support for Microchip MCP4728
|
||||
*
|
||||
* Copyright (C) 2023 Andrea Collamati <andrea.collamati@gmail.com>
|
||||
*
|
||||
* Based on mcp4725 by Peter Meerwald <pmeerw@pmeerw.net>
|
||||
*
|
||||
* Driver for the Microchip I2C 12-bit digital-to-analog quad channels
|
||||
* converter (DAC).
|
||||
*
|
||||
* (7-bit I2C slave address 0x60, the three LSBs can be configured in
|
||||
* hardware)
|
||||
*/
|
||||
|
||||
#include <linux/bitfield.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/err.h>
|
||||
#include <linux/i2c.h>
|
||||
#include <linux/iio/iio.h>
|
||||
#include <linux/iio/sysfs.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/mod_devicetable.h>
|
||||
#include <linux/property.h>
|
||||
#include <linux/regulator/consumer.h>
|
||||
|
||||
#define MCP4728_RESOLUTION 12
|
||||
#define MCP4728_N_CHANNELS 4
|
||||
|
||||
#define MCP4728_CMD_MASK GENMASK(7, 3)
|
||||
#define MCP4728_CHSEL_MASK GENMASK(2, 1)
|
||||
#define MCP4728_UDAC_MASK BIT(0)
|
||||
|
||||
#define MCP4728_VREF_MASK BIT(7)
|
||||
#define MCP4728_PDMODE_MASK GENMASK(6, 5)
|
||||
#define MCP4728_GAIN_MASK BIT(4)
|
||||
|
||||
#define MCP4728_DAC_H_MASK GENMASK(3, 0)
|
||||
#define MCP4728_DAC_L_MASK GENMASK(7, 0)
|
||||
|
||||
#define MCP4728_RDY_MASK BIT(7)
|
||||
|
||||
#define MCP4728_MW_CMD 0x08 /* Multiwrite Command */
|
||||
#define MCP4728_SW_CMD 0x0A /* Sequential Write Command with EEPROM */
|
||||
|
||||
#define MCP4728_READ_RESPONSE_LEN (MCP4728_N_CHANNELS * 3 * 2)
|
||||
#define MCP4728_WRITE_EEPROM_LEN (1 + MCP4728_N_CHANNELS * 2)
|
||||
|
||||
enum vref_mode {
|
||||
MCP4728_VREF_EXTERNAL_VDD = 0,
|
||||
MCP4728_VREF_INTERNAL_2048mV = 1,
|
||||
};
|
||||
|
||||
enum gain_mode {
|
||||
MCP4728_GAIN_X1 = 0,
|
||||
MCP4728_GAIN_X2 = 1,
|
||||
};
|
||||
|
||||
enum iio_powerdown_mode {
|
||||
MCP4728_IIO_1K,
|
||||
MCP4728_IIO_100K,
|
||||
MCP4728_IIO_500K,
|
||||
};
|
||||
|
||||
struct mcp4728_channel_data {
|
||||
enum vref_mode ref_mode;
|
||||
enum iio_powerdown_mode pd_mode;
|
||||
enum gain_mode g_mode;
|
||||
u16 dac_value;
|
||||
};
|
||||
|
||||
/* MCP4728 Full Scale Ranges
|
||||
* the device available ranges are
|
||||
* - VREF = VDD FSR = from 0.0V to VDD
|
||||
* - VREF = Internal Gain = 1 FSR = from 0.0V to VREF
|
||||
* - VREF = Internal Gain = 2 FSR = from 0.0V to 2*VREF
|
||||
*/
|
||||
enum mcp4728_scale {
|
||||
MCP4728_SCALE_VDD,
|
||||
MCP4728_SCALE_VINT_NO_GAIN,
|
||||
MCP4728_SCALE_VINT_GAIN_X2,
|
||||
MCP4728_N_SCALES
|
||||
};
|
||||
|
||||
struct mcp4728_data {
|
||||
struct i2c_client *client;
|
||||
struct regulator *vdd_reg;
|
||||
bool powerdown;
|
||||
int scales_avail[MCP4728_N_SCALES * 2];
|
||||
struct mcp4728_channel_data chdata[MCP4728_N_CHANNELS];
|
||||
};
|
||||
|
||||
#define MCP4728_CHAN(chan) { \
|
||||
.type = IIO_VOLTAGE, \
|
||||
.output = 1, \
|
||||
.indexed = 1, \
|
||||
.channel = chan, \
|
||||
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
|
||||
BIT(IIO_CHAN_INFO_SCALE), \
|
||||
.info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SCALE), \
|
||||
.ext_info = mcp4728_ext_info, \
|
||||
}
|
||||
|
||||
static int mcp4728_suspend(struct device *dev);
|
||||
static int mcp4728_resume(struct device *dev);
|
||||
|
||||
static ssize_t mcp4728_store_eeprom(struct device *dev,
|
||||
struct device_attribute *attr,
|
||||
const char *buf, size_t len)
|
||||
{
|
||||
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
|
||||
struct mcp4728_data *data = iio_priv(indio_dev);
|
||||
u8 outbuf[MCP4728_WRITE_EEPROM_LEN];
|
||||
int tries = 20;
|
||||
u8 inbuf[3];
|
||||
bool state;
|
||||
int ret;
|
||||
unsigned int i;
|
||||
|
||||
ret = kstrtobool(buf, &state);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
if (!state)
|
||||
return 0;
|
||||
|
||||
outbuf[0] = FIELD_PREP(MCP4728_CMD_MASK, MCP4728_SW_CMD);
|
||||
|
||||
for (i = 0; i < MCP4728_N_CHANNELS; i++) {
|
||||
struct mcp4728_channel_data *ch = &data->chdata[i];
|
||||
int offset = 1 + i * 2;
|
||||
|
||||
outbuf[offset] = FIELD_PREP(MCP4728_VREF_MASK, ch->ref_mode);
|
||||
|
||||
if (data->powerdown) {
|
||||
u8 mcp4728_pd_mode = ch->pd_mode + 1;
|
||||
|
||||
outbuf[offset] |= FIELD_PREP(MCP4728_PDMODE_MASK,
|
||||
mcp4728_pd_mode);
|
||||
}
|
||||
|
||||
outbuf[offset] |= FIELD_PREP(MCP4728_GAIN_MASK, ch->g_mode);
|
||||
outbuf[offset] |=
|
||||
FIELD_PREP(MCP4728_DAC_H_MASK, ch->dac_value >> 8);
|
||||
outbuf[offset + 1] =
|
||||
FIELD_PREP(MCP4728_DAC_L_MASK, ch->dac_value);
|
||||
}
|
||||
|
||||
ret = i2c_master_send(data->client, outbuf, MCP4728_WRITE_EEPROM_LEN);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
else if (ret != MCP4728_WRITE_EEPROM_LEN)
|
||||
return -EIO;
|
||||
|
||||
/* wait RDY signal for write complete, takes up to 50ms */
|
||||
while (tries--) {
|
||||
msleep(20);
|
||||
ret = i2c_master_recv(data->client, inbuf, 3);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
else if (ret != 3)
|
||||
return -EIO;
|
||||
|
||||
if (FIELD_GET(MCP4728_RDY_MASK, inbuf[0]))
|
||||
break;
|
||||
}
|
||||
|
||||
if (tries < 0) {
|
||||
dev_err(&data->client->dev, "%s failed, incomplete\n",
|
||||
__func__);
|
||||
return -EIO;
|
||||
}
|
||||
return len;
|
||||
}
|
||||
|
||||
static IIO_DEVICE_ATTR(store_eeprom, 0200, NULL, mcp4728_store_eeprom, 0);
|
||||
|
||||
static struct attribute *mcp4728_attributes[] = {
|
||||
&iio_dev_attr_store_eeprom.dev_attr.attr,
|
||||
NULL,
|
||||
};
|
||||
|
||||
static const struct attribute_group mcp4728_attribute_group = {
|
||||
.attrs = mcp4728_attributes,
|
||||
};
|
||||
|
||||
static int mcp4728_program_channel_cfg(int channel, struct iio_dev *indio_dev)
|
||||
{
|
||||
struct mcp4728_data *data = iio_priv(indio_dev);
|
||||
struct mcp4728_channel_data *ch = &data->chdata[channel];
|
||||
u8 outbuf[3];
|
||||
int ret;
|
||||
|
||||
outbuf[0] = FIELD_PREP(MCP4728_CMD_MASK, MCP4728_MW_CMD);
|
||||
outbuf[0] |= FIELD_PREP(MCP4728_CHSEL_MASK, channel);
|
||||
outbuf[0] |= FIELD_PREP(MCP4728_UDAC_MASK, 0);
|
||||
|
||||
outbuf[1] = FIELD_PREP(MCP4728_VREF_MASK, ch->ref_mode);
|
||||
|
||||
if (data->powerdown)
|
||||
outbuf[1] |= FIELD_PREP(MCP4728_PDMODE_MASK, ch->pd_mode + 1);
|
||||
|
||||
outbuf[1] |= FIELD_PREP(MCP4728_GAIN_MASK, ch->g_mode);
|
||||
outbuf[1] |= FIELD_PREP(MCP4728_DAC_H_MASK, ch->dac_value >> 8);
|
||||
outbuf[2] = FIELD_PREP(MCP4728_DAC_L_MASK, ch->dac_value);
|
||||
|
||||
ret = i2c_master_send(data->client, outbuf, 3);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
else if (ret != 3)
|
||||
return -EIO;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const char *const mcp4728_powerdown_modes[] = { "1kohm_to_gnd",
|
||||
"100kohm_to_gnd",
|
||||
"500kohm_to_gnd" };
|
||||
|
||||
static int mcp4728_get_powerdown_mode(struct iio_dev *indio_dev,
|
||||
const struct iio_chan_spec *chan)
|
||||
{
|
||||
struct mcp4728_data *data = iio_priv(indio_dev);
|
||||
|
||||
return data->chdata[chan->channel].pd_mode;
|
||||
}
|
||||
|
||||
static int mcp4728_set_powerdown_mode(struct iio_dev *indio_dev,
|
||||
const struct iio_chan_spec *chan,
|
||||
unsigned int mode)
|
||||
{
|
||||
struct mcp4728_data *data = iio_priv(indio_dev);
|
||||
|
||||
data->chdata[chan->channel].pd_mode = mode;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static ssize_t mcp4728_read_powerdown(struct iio_dev *indio_dev,
|
||||
uintptr_t private,
|
||||
const struct iio_chan_spec *chan,
|
||||
char *buf)
|
||||
{
|
||||
struct mcp4728_data *data = iio_priv(indio_dev);
|
||||
|
||||
return sysfs_emit(buf, "%d\n", data->powerdown);
|
||||
}
|
||||
|
||||
static ssize_t mcp4728_write_powerdown(struct iio_dev *indio_dev,
|
||||
uintptr_t private,
|
||||
const struct iio_chan_spec *chan,
|
||||
const char *buf, size_t len)
|
||||
{
|
||||
struct mcp4728_data *data = iio_priv(indio_dev);
|
||||
bool state;
|
||||
int ret;
|
||||
|
||||
ret = kstrtobool(buf, &state);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
if (state)
|
||||
ret = mcp4728_suspend(&data->client->dev);
|
||||
else
|
||||
ret = mcp4728_resume(&data->client->dev);
|
||||
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
return len;
|
||||
}
|
||||
|
||||
static const struct iio_enum mcp4728_powerdown_mode_enum = {
|
||||
.items = mcp4728_powerdown_modes,
|
||||
.num_items = ARRAY_SIZE(mcp4728_powerdown_modes),
|
||||
.get = mcp4728_get_powerdown_mode,
|
||||
.set = mcp4728_set_powerdown_mode,
|
||||
};
|
||||
|
||||
static const struct iio_chan_spec_ext_info mcp4728_ext_info[] = {
|
||||
{
|
||||
.name = "powerdown",
|
||||
.read = mcp4728_read_powerdown,
|
||||
.write = mcp4728_write_powerdown,
|
||||
.shared = IIO_SEPARATE,
|
||||
},
|
||||
IIO_ENUM("powerdown_mode", IIO_SEPARATE, &mcp4728_powerdown_mode_enum),
|
||||
IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE,
|
||||
&mcp4728_powerdown_mode_enum),
|
||||
{},
|
||||
};
|
||||
|
||||
static const struct iio_chan_spec mcp4728_channels[MCP4728_N_CHANNELS] = {
|
||||
MCP4728_CHAN(0),
|
||||
MCP4728_CHAN(1),
|
||||
MCP4728_CHAN(2),
|
||||
MCP4728_CHAN(3),
|
||||
};
|
||||
|
||||
static void mcp4728_get_scale_avail(enum mcp4728_scale scale,
|
||||
struct mcp4728_data *data, int *val,
|
||||
int *val2)
|
||||
{
|
||||
*val = data->scales_avail[scale * 2];
|
||||
*val2 = data->scales_avail[scale * 2 + 1];
|
||||
}
|
||||
|
||||
static void mcp4728_get_scale(int channel, struct mcp4728_data *data, int *val,
|
||||
int *val2)
|
||||
{
|
||||
int ref_mode = data->chdata[channel].ref_mode;
|
||||
int g_mode = data->chdata[channel].g_mode;
|
||||
|
||||
if (ref_mode == MCP4728_VREF_EXTERNAL_VDD) {
|
||||
mcp4728_get_scale_avail(MCP4728_SCALE_VDD, data, val, val2);
|
||||
} else {
|
||||
if (g_mode == MCP4728_GAIN_X1) {
|
||||
mcp4728_get_scale_avail(MCP4728_SCALE_VINT_NO_GAIN,
|
||||
data, val, val2);
|
||||
} else {
|
||||
mcp4728_get_scale_avail(MCP4728_SCALE_VINT_GAIN_X2,
|
||||
data, val, val2);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
static int mcp4728_find_matching_scale(struct mcp4728_data *data, int val,
|
||||
int val2)
|
||||
{
|
||||
for (int i = 0; i < MCP4728_N_SCALES; i++) {
|
||||
if (data->scales_avail[i * 2] == val &&
|
||||
data->scales_avail[i * 2 + 1] == val2)
|
||||
return i;
|
||||
}
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
static int mcp4728_set_scale(int channel, struct mcp4728_data *data, int val,
|
||||
int val2)
|
||||
{
|
||||
int scale = mcp4728_find_matching_scale(data, val, val2);
|
||||
|
||||
if (scale < 0)
|
||||
return scale;
|
||||
|
||||
switch (scale) {
|
||||
case MCP4728_SCALE_VDD:
|
||||
data->chdata[channel].ref_mode = MCP4728_VREF_EXTERNAL_VDD;
|
||||
return 0;
|
||||
case MCP4728_SCALE_VINT_NO_GAIN:
|
||||
data->chdata[channel].ref_mode = MCP4728_VREF_INTERNAL_2048mV;
|
||||
data->chdata[channel].g_mode = MCP4728_GAIN_X1;
|
||||
return 0;
|
||||
case MCP4728_SCALE_VINT_GAIN_X2:
|
||||
data->chdata[channel].ref_mode = MCP4728_VREF_INTERNAL_2048mV;
|
||||
data->chdata[channel].g_mode = MCP4728_GAIN_X2;
|
||||
return 0;
|
||||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
}
|
||||
|
||||
static int mcp4728_read_raw(struct iio_dev *indio_dev,
|
||||
struct iio_chan_spec const *chan, int *val,
|
||||
int *val2, long mask)
|
||||
{
|
||||
struct mcp4728_data *data = iio_priv(indio_dev);
|
||||
|
||||
switch (mask) {
|
||||
case IIO_CHAN_INFO_RAW:
|
||||
*val = data->chdata[chan->channel].dac_value;
|
||||
return IIO_VAL_INT;
|
||||
case IIO_CHAN_INFO_SCALE:
|
||||
mcp4728_get_scale(chan->channel, data, val, val2);
|
||||
return IIO_VAL_INT_PLUS_MICRO;
|
||||
}
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
static int mcp4728_write_raw(struct iio_dev *indio_dev,
|
||||
struct iio_chan_spec const *chan, int val,
|
||||
int val2, long mask)
|
||||
{
|
||||
struct mcp4728_data *data = iio_priv(indio_dev);
|
||||
int ret;
|
||||
|
||||
switch (mask) {
|
||||
case IIO_CHAN_INFO_RAW:
|
||||
if (val < 0 || val > GENMASK(MCP4728_RESOLUTION - 1, 0))
|
||||
return -EINVAL;
|
||||
data->chdata[chan->channel].dac_value = val;
|
||||
return mcp4728_program_channel_cfg(chan->channel, indio_dev);
|
||||
case IIO_CHAN_INFO_SCALE:
|
||||
ret = mcp4728_set_scale(chan->channel, data, val, val2);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
return mcp4728_program_channel_cfg(chan->channel, indio_dev);
|
||||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
}
|
||||
|
||||
static void mcp4728_init_scale_avail(enum mcp4728_scale scale, int vref_mv,
|
||||
struct mcp4728_data *data)
|
||||
{
|
||||
s64 tmp;
|
||||
int value_micro;
|
||||
int value_int;
|
||||
|
||||
tmp = (s64)vref_mv * 1000000LL >> MCP4728_RESOLUTION;
|
||||
value_int = div_s64_rem(tmp, 1000000LL, &value_micro);
|
||||
|
||||
data->scales_avail[scale * 2] = value_int;
|
||||
data->scales_avail[scale * 2 + 1] = value_micro;
|
||||
}
|
||||
|
||||
static int mcp4728_init_scales_avail(struct mcp4728_data *data)
|
||||
{
|
||||
int ret;
|
||||
|
||||
ret = regulator_get_voltage(data->vdd_reg);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
mcp4728_init_scale_avail(MCP4728_SCALE_VDD, ret / 1000, data);
|
||||
mcp4728_init_scale_avail(MCP4728_SCALE_VINT_NO_GAIN, 2048, data);
|
||||
mcp4728_init_scale_avail(MCP4728_SCALE_VINT_GAIN_X2, 4096, data);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int mcp4728_read_avail(struct iio_dev *indio_dev,
|
||||
struct iio_chan_spec const *chan,
|
||||
const int **vals, int *type, int *length,
|
||||
long info)
|
||||
{
|
||||
struct mcp4728_data *data = iio_priv(indio_dev);
|
||||
|
||||
switch (info) {
|
||||
case IIO_CHAN_INFO_SCALE:
|
||||
*type = IIO_VAL_INT_PLUS_MICRO;
|
||||
|
||||
switch (chan->type) {
|
||||
case IIO_VOLTAGE:
|
||||
*vals = data->scales_avail;
|
||||
*length = MCP4728_N_SCALES * 2;
|
||||
return IIO_AVAIL_LIST;
|
||||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
}
|
||||
|
||||
static const struct iio_info mcp4728_info = {
|
||||
.read_raw = mcp4728_read_raw,
|
||||
.write_raw = mcp4728_write_raw,
|
||||
.read_avail = &mcp4728_read_avail,
|
||||
.attrs = &mcp4728_attribute_group,
|
||||
};
|
||||
|
||||
static int mcp4728_suspend(struct device *dev)
|
||||
{
|
||||
struct iio_dev *indio_dev = dev_get_drvdata(dev);
|
||||
struct mcp4728_data *data = iio_priv(indio_dev);
|
||||
unsigned int i;
|
||||
|
||||
data->powerdown = true;
|
||||
|
||||
for (i = 0; i < MCP4728_N_CHANNELS; i++) {
|
||||
int err = mcp4728_program_channel_cfg(i, indio_dev);
|
||||
|
||||
if (err)
|
||||
return err;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int mcp4728_resume(struct device *dev)
|
||||
{
|
||||
struct iio_dev *indio_dev = dev_get_drvdata(dev);
|
||||
struct mcp4728_data *data = iio_priv(indio_dev);
|
||||
int err = 0;
|
||||
unsigned int i;
|
||||
|
||||
data->powerdown = false;
|
||||
|
||||
for (i = 0; i < MCP4728_N_CHANNELS; i++) {
|
||||
int ret = mcp4728_program_channel_cfg(i, indio_dev);
|
||||
|
||||
if (ret)
|
||||
err = ret;
|
||||
}
|
||||
return err;
|
||||
}
|
||||
|
||||
static DEFINE_SIMPLE_DEV_PM_OPS(mcp4728_pm_ops, mcp4728_suspend,
|
||||
mcp4728_resume);
|
||||
|
||||
static int mcp4728_init_channels_data(struct mcp4728_data *data)
|
||||
{
|
||||
u8 inbuf[MCP4728_READ_RESPONSE_LEN];
|
||||
int ret;
|
||||
unsigned int i;
|
||||
|
||||
ret = i2c_master_recv(data->client, inbuf, MCP4728_READ_RESPONSE_LEN);
|
||||
if (ret < 0) {
|
||||
return dev_err_probe(&data->client->dev, ret,
|
||||
"failed to read mcp4728 conf.\n");
|
||||
} else if (ret != MCP4728_READ_RESPONSE_LEN) {
|
||||
return dev_err_probe(&data->client->dev, -EIO,
|
||||
"failed to read mcp4728 conf. Wrong Response Len ret=%d\n",
|
||||
ret);
|
||||
}
|
||||
|
||||
for (i = 0; i < MCP4728_N_CHANNELS; i++) {
|
||||
struct mcp4728_channel_data *ch = &data->chdata[i];
|
||||
u8 r2 = inbuf[i * 6 + 1];
|
||||
u8 r3 = inbuf[i * 6 + 2];
|
||||
|
||||
ch->dac_value = FIELD_GET(MCP4728_DAC_H_MASK, r2) << 8 |
|
||||
FIELD_GET(MCP4728_DAC_L_MASK, r3);
|
||||
ch->ref_mode = FIELD_GET(MCP4728_VREF_MASK, r2);
|
||||
ch->pd_mode = FIELD_GET(MCP4728_PDMODE_MASK, r2);
|
||||
ch->g_mode = FIELD_GET(MCP4728_GAIN_MASK, r2);
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void mcp4728_reg_disable(void *reg)
|
||||
{
|
||||
regulator_disable(reg);
|
||||
}
|
||||
|
||||
static int mcp4728_probe(struct i2c_client *client)
|
||||
{
|
||||
const struct i2c_device_id *id = i2c_client_get_device_id(client);
|
||||
struct mcp4728_data *data;
|
||||
struct iio_dev *indio_dev;
|
||||
int err;
|
||||
|
||||
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
|
||||
if (!indio_dev)
|
||||
return -ENOMEM;
|
||||
|
||||
data = iio_priv(indio_dev);
|
||||
i2c_set_clientdata(client, indio_dev);
|
||||
data->client = client;
|
||||
|
||||
data->vdd_reg = devm_regulator_get(&client->dev, "vdd");
|
||||
if (IS_ERR(data->vdd_reg))
|
||||
return PTR_ERR(data->vdd_reg);
|
||||
|
||||
err = regulator_enable(data->vdd_reg);
|
||||
if (err)
|
||||
return err;
|
||||
|
||||
err = devm_add_action_or_reset(&client->dev, mcp4728_reg_disable,
|
||||
data->vdd_reg);
|
||||
if (err)
|
||||
return err;
|
||||
|
||||
/*
|
||||
* MCP4728 has internal EEPROM that save each channel boot
|
||||
* configuration. It means that device configuration is unknown to the
|
||||
* driver at kernel boot. mcp4728_init_channels_data() reads back DAC
|
||||
* settings and stores them in data structure.
|
||||
*/
|
||||
err = mcp4728_init_channels_data(data);
|
||||
if (err) {
|
||||
return dev_err_probe(&client->dev, err,
|
||||
"failed to read mcp4728 current configuration\n");
|
||||
}
|
||||
|
||||
err = mcp4728_init_scales_avail(data);
|
||||
if (err) {
|
||||
return dev_err_probe(&client->dev, err,
|
||||
"failed to init scales\n");
|
||||
}
|
||||
|
||||
indio_dev->name = id->name;
|
||||
indio_dev->info = &mcp4728_info;
|
||||
indio_dev->channels = mcp4728_channels;
|
||||
indio_dev->num_channels = MCP4728_N_CHANNELS;
|
||||
indio_dev->modes = INDIO_DIRECT_MODE;
|
||||
|
||||
return devm_iio_device_register(&client->dev, indio_dev);
|
||||
}
|
||||
|
||||
static const struct i2c_device_id mcp4728_id[] = {
|
||||
{ "mcp4728", 0 },
|
||||
{}
|
||||
};
|
||||
MODULE_DEVICE_TABLE(i2c, mcp4728_id);
|
||||
|
||||
static const struct of_device_id mcp4728_of_match[] = {
|
||||
{ .compatible = "microchip,mcp4728" },
|
||||
{}
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, mcp4728_of_match);
|
||||
|
||||
static struct i2c_driver mcp4728_driver = {
|
||||
.driver = {
|
||||
.name = "mcp4728",
|
||||
.of_match_table = mcp4728_of_match,
|
||||
.pm = pm_sleep_ptr(&mcp4728_pm_ops),
|
||||
},
|
||||
.probe = mcp4728_probe,
|
||||
.id_table = mcp4728_id,
|
||||
};
|
||||
module_i2c_driver(mcp4728_driver);
|
||||
|
||||
MODULE_AUTHOR("Andrea Collamati <andrea.collamati@gmail.com>");
|
||||
MODULE_DESCRIPTION("MCP4728 12-bit DAC");
|
||||
MODULE_LICENSE("GPL");
|
||||
Loading…
Reference in New Issue
Block a user