alistair23-linux/drivers/iio/dac/ti-dac5571.c
Jonathan Cameron 16723c6eaa iio:dac:ti-dac5571: Drop of_match_ptr and CONFIG_OF protections
These prevent the use of this driver with ACPI via PRP0001 and are
an example of an anti pattern I'm trying to remove from IIO.
Hence drop them from this driver.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Link: https://lore.kernel.org/r/20200910173242.621168-16-jic23@kernel.org
2020-09-21 18:41:28 +01:00

428 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* ti-dac5571.c - Texas Instruments 8/10/12-bit 1/4-channel DAC driver
*
* Copyright (C) 2018 Prevas A/S
*
* https://www.ti.com/lit/ds/symlink/dac5571.pdf
* https://www.ti.com/lit/ds/symlink/dac6571.pdf
* https://www.ti.com/lit/ds/symlink/dac7571.pdf
* https://www.ti.com/lit/ds/symlink/dac5574.pdf
* https://www.ti.com/lit/ds/symlink/dac6574.pdf
* https://www.ti.com/lit/ds/symlink/dac7574.pdf
* https://www.ti.com/lit/ds/symlink/dac5573.pdf
* https://www.ti.com/lit/ds/symlink/dac6573.pdf
* https://www.ti.com/lit/ds/symlink/dac7573.pdf
*/
#include <linux/iio/iio.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/regulator/consumer.h>
enum chip_id {
single_8bit, single_10bit, single_12bit,
quad_8bit, quad_10bit, quad_12bit
};
struct dac5571_spec {
u8 num_channels;
u8 resolution;
};
static const struct dac5571_spec dac5571_spec[] = {
[single_8bit] = {.num_channels = 1, .resolution = 8},
[single_10bit] = {.num_channels = 1, .resolution = 10},
[single_12bit] = {.num_channels = 1, .resolution = 12},
[quad_8bit] = {.num_channels = 4, .resolution = 8},
[quad_10bit] = {.num_channels = 4, .resolution = 10},
[quad_12bit] = {.num_channels = 4, .resolution = 12},
};
struct dac5571_data {
struct i2c_client *client;
int id;
struct mutex lock;
struct regulator *vref;
u16 val[4];
bool powerdown[4];
u8 powerdown_mode[4];
struct dac5571_spec const *spec;
int (*dac5571_cmd)(struct dac5571_data *data, int channel, u16 val);
int (*dac5571_pwrdwn)(struct dac5571_data *data, int channel, u8 pwrdwn);
u8 buf[3] ____cacheline_aligned;
};
#define DAC5571_POWERDOWN(mode) ((mode) + 1)
#define DAC5571_POWERDOWN_FLAG BIT(0)
#define DAC5571_CHANNEL_SELECT 1
#define DAC5571_LOADMODE_DIRECT BIT(4)
#define DAC5571_SINGLE_PWRDWN_BITS 4
#define DAC5571_QUAD_PWRDWN_BITS 6
static int dac5571_cmd_single(struct dac5571_data *data, int channel, u16 val)
{
unsigned int shift;
shift = 12 - data->spec->resolution;
data->buf[1] = val << shift;
data->buf[0] = val >> (8 - shift);
if (i2c_master_send(data->client, data->buf, 2) != 2)
return -EIO;
return 0;
}
static int dac5571_cmd_quad(struct dac5571_data *data, int channel, u16 val)
{
unsigned int shift;
shift = 16 - data->spec->resolution;
data->buf[2] = val << shift;
data->buf[1] = (val >> (8 - shift));
data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) |
DAC5571_LOADMODE_DIRECT;
if (i2c_master_send(data->client, data->buf, 3) != 3)
return -EIO;
return 0;
}
static int dac5571_pwrdwn_single(struct dac5571_data *data, int channel, u8 pwrdwn)
{
data->buf[1] = 0;
data->buf[0] = pwrdwn << DAC5571_SINGLE_PWRDWN_BITS;
if (i2c_master_send(data->client, data->buf, 2) != 2)
return -EIO;
return 0;
}
static int dac5571_pwrdwn_quad(struct dac5571_data *data, int channel, u8 pwrdwn)
{
data->buf[2] = 0;
data->buf[1] = pwrdwn << DAC5571_QUAD_PWRDWN_BITS;
data->buf[0] = (channel << DAC5571_CHANNEL_SELECT) |
DAC5571_LOADMODE_DIRECT | DAC5571_POWERDOWN_FLAG;
if (i2c_master_send(data->client, data->buf, 3) != 3)
return -EIO;
return 0;
}
static const char *const dac5571_powerdown_modes[] = {
"1kohm_to_gnd", "100kohm_to_gnd", "three_state",
};
static int dac5571_get_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
struct dac5571_data *data = iio_priv(indio_dev);
return data->powerdown_mode[chan->channel];
}
static int dac5571_set_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
unsigned int mode)
{
struct dac5571_data *data = iio_priv(indio_dev);
int ret = 0;
if (data->powerdown_mode[chan->channel] == mode)
return 0;
mutex_lock(&data->lock);
if (data->powerdown[chan->channel]) {
ret = data->dac5571_pwrdwn(data, chan->channel,
DAC5571_POWERDOWN(mode));
if (ret)
goto out;
}
data->powerdown_mode[chan->channel] = mode;
out:
mutex_unlock(&data->lock);
return ret;
}
static const struct iio_enum dac5571_powerdown_mode = {
.items = dac5571_powerdown_modes,
.num_items = ARRAY_SIZE(dac5571_powerdown_modes),
.get = dac5571_get_powerdown_mode,
.set = dac5571_set_powerdown_mode,
};
static ssize_t dac5571_read_powerdown(struct iio_dev *indio_dev,
uintptr_t private,
const struct iio_chan_spec *chan,
char *buf)
{
struct dac5571_data *data = iio_priv(indio_dev);
return sprintf(buf, "%d\n", data->powerdown[chan->channel]);
}
static ssize_t dac5571_write_powerdown(struct iio_dev *indio_dev,
uintptr_t private,
const struct iio_chan_spec *chan,
const char *buf, size_t len)
{
struct dac5571_data *data = iio_priv(indio_dev);
bool powerdown;
int ret;
ret = strtobool(buf, &powerdown);
if (ret)
return ret;
if (data->powerdown[chan->channel] == powerdown)
return len;
mutex_lock(&data->lock);
if (powerdown)
ret = data->dac5571_pwrdwn(data, chan->channel,
DAC5571_POWERDOWN(data->powerdown_mode[chan->channel]));
else
ret = data->dac5571_cmd(data, chan->channel,
data->val[chan->channel]);
if (ret)
goto out;
data->powerdown[chan->channel] = powerdown;
out:
mutex_unlock(&data->lock);
return ret ? ret : len;
}
static const struct iio_chan_spec_ext_info dac5571_ext_info[] = {
{
.name = "powerdown",
.read = dac5571_read_powerdown,
.write = dac5571_write_powerdown,
.shared = IIO_SEPARATE,
},
IIO_ENUM("powerdown_mode", IIO_SEPARATE, &dac5571_powerdown_mode),
IIO_ENUM_AVAILABLE("powerdown_mode", &dac5571_powerdown_mode),
{},
};
#define dac5571_CHANNEL(chan, name) { \
.type = IIO_VOLTAGE, \
.channel = (chan), \
.address = (chan), \
.indexed = true, \
.output = true, \
.datasheet_name = name, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
.ext_info = dac5571_ext_info, \
}
static const struct iio_chan_spec dac5571_channels[] = {
dac5571_CHANNEL(0, "A"),
dac5571_CHANNEL(1, "B"),
dac5571_CHANNEL(2, "C"),
dac5571_CHANNEL(3, "D"),
};
static int dac5571_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct dac5571_data *data = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
*val = data->val[chan->channel];
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
ret = regulator_get_voltage(data->vref);
if (ret < 0)
return ret;
*val = ret / 1000;
*val2 = data->spec->resolution;
return IIO_VAL_FRACTIONAL_LOG2;
default:
return -EINVAL;
}
}
static int dac5571_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct dac5571_data *data = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
if (data->val[chan->channel] == val)
return 0;
if (val >= (1 << data->spec->resolution) || val < 0)
return -EINVAL;
if (data->powerdown[chan->channel])
return -EBUSY;
mutex_lock(&data->lock);
ret = data->dac5571_cmd(data, chan->channel, val);
if (ret == 0)
data->val[chan->channel] = val;
mutex_unlock(&data->lock);
return ret;
default:
return -EINVAL;
}
}
static int dac5571_write_raw_get_fmt(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
long mask)
{
return IIO_VAL_INT;
}
static const struct iio_info dac5571_info = {
.read_raw = dac5571_read_raw,
.write_raw = dac5571_write_raw,
.write_raw_get_fmt = dac5571_write_raw_get_fmt,
};
static int dac5571_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
const struct dac5571_spec *spec;
struct dac5571_data *data;
struct iio_dev *indio_dev;
int ret, i;
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
i2c_set_clientdata(client, indio_dev);
data->client = client;
indio_dev->info = &dac5571_info;
indio_dev->name = id->name;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = dac5571_channels;
spec = &dac5571_spec[id->driver_data];
indio_dev->num_channels = spec->num_channels;
data->spec = spec;
data->vref = devm_regulator_get(dev, "vref");
if (IS_ERR(data->vref))
return PTR_ERR(data->vref);
ret = regulator_enable(data->vref);
if (ret < 0)
return ret;
mutex_init(&data->lock);
switch (spec->num_channels) {
case 1:
data->dac5571_cmd = dac5571_cmd_single;
data->dac5571_pwrdwn = dac5571_pwrdwn_single;
break;
case 4:
data->dac5571_cmd = dac5571_cmd_quad;
data->dac5571_pwrdwn = dac5571_pwrdwn_quad;
break;
default:
goto err;
}
for (i = 0; i < spec->num_channels; i++) {
ret = data->dac5571_cmd(data, i, 0);
if (ret) {
dev_err(dev, "failed to initialize channel %d to 0\n", i);
goto err;
}
}
ret = iio_device_register(indio_dev);
if (ret)
goto err;
return 0;
err:
regulator_disable(data->vref);
return ret;
}
static int dac5571_remove(struct i2c_client *i2c)
{
struct iio_dev *indio_dev = i2c_get_clientdata(i2c);
struct dac5571_data *data = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
regulator_disable(data->vref);
return 0;
}
static const struct of_device_id dac5571_of_id[] = {
{.compatible = "ti,dac5571"},
{.compatible = "ti,dac6571"},
{.compatible = "ti,dac7571"},
{.compatible = "ti,dac5574"},
{.compatible = "ti,dac6574"},
{.compatible = "ti,dac7574"},
{.compatible = "ti,dac5573"},
{.compatible = "ti,dac6573"},
{.compatible = "ti,dac7573"},
{}
};
MODULE_DEVICE_TABLE(of, dac5571_of_id);
static const struct i2c_device_id dac5571_id[] = {
{"dac5571", single_8bit},
{"dac6571", single_10bit},
{"dac7571", single_12bit},
{"dac5574", quad_8bit},
{"dac6574", quad_10bit},
{"dac7574", quad_12bit},
{"dac5573", quad_8bit},
{"dac6573", quad_10bit},
{"dac7573", quad_12bit},
{}
};
MODULE_DEVICE_TABLE(i2c, dac5571_id);
static struct i2c_driver dac5571_driver = {
.driver = {
.name = "ti-dac5571",
.of_match_table = dac5571_of_id,
},
.probe = dac5571_probe,
.remove = dac5571_remove,
.id_table = dac5571_id,
};
module_i2c_driver(dac5571_driver);
MODULE_AUTHOR("Sean Nyekjaer <sean@geanix.dk>");
MODULE_DESCRIPTION("Texas Instruments 8/10/12-bit 1/4-channel DAC driver");
MODULE_LICENSE("GPL v2");