mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-23 20:24:12 +08:00
iio: potentiometer: Add driver for Microchip MCP41xxx/42xxx
This patch adds driver support for the Microchip MCP41xxx/42xxx family of digital potentiometers: DEVICE Wipers Positions Resistance (kOhm) MCP41010 1 256 10 MCP41050 1 256 50 MCP41100 1 256 100 MCP42010 2 256 10 MCP42050 2 256 50 MCP42100 2 256 100 Datasheet: http://ww1.microchip.com/downloads/en/devicedoc/11195c.pdf Signed-off-by: Chris Coffey <cmc@babblebit.net> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Chris Coffey
Jonathan Cameron
parent
f71b3c9912
commit
092cb71a60
@ -90,6 +90,18 @@ config MCP4531
|
||||
To compile this driver as a module, choose M here: the
|
||||
module will be called mcp4531.
|
||||
|
||||
config MCP41010
|
||||
tristate "Microchip MCP41xxx/MCP42xxx Digital Potentiometer driver"
|
||||
depends on SPI
|
||||
help
|
||||
Say yes here to build support for the Microchip
|
||||
MCP41010, MCP41050, MCP41100,
|
||||
MCP42010, MCP42050, MCP42100
|
||||
digital potentiometer chips.
|
||||
|
||||
To compile this driver as a module, choose M here: the
|
||||
module will be called mcp41010.
|
||||
|
||||
config TPL0102
|
||||
tristate "Texas Instruments digital potentiometer driver"
|
||||
depends on I2C
|
||||
|
||||
@ -11,4 +11,5 @@ obj-$(CONFIG_MAX5487) += max5487.o
|
||||
obj-$(CONFIG_MCP4018) += mcp4018.o
|
||||
obj-$(CONFIG_MCP4131) += mcp4131.o
|
||||
obj-$(CONFIG_MCP4531) += mcp4531.o
|
||||
obj-$(CONFIG_MCP41010) += mcp41010.o
|
||||
obj-$(CONFIG_TPL0102) += tpl0102.o
|
||||
|
||||
203
drivers/iio/potentiometer/mcp41010.c
Normal file
203
drivers/iio/potentiometer/mcp41010.c
Normal file
@ -0,0 +1,203 @@
|
||||
// SPDX-License-Identifier: GPL-2.0
|
||||
/*
|
||||
* Industrial I/O driver for Microchip digital potentiometers
|
||||
*
|
||||
* Copyright (c) 2018 Chris Coffey <cmc@babblebit.net>
|
||||
* Based on: Slawomir Stepien's code from mcp4131.c
|
||||
*
|
||||
* Datasheet: http://ww1.microchip.com/downloads/en/devicedoc/11195c.pdf
|
||||
*
|
||||
* DEVID #Wipers #Positions Resistance (kOhm)
|
||||
* mcp41010 1 256 10
|
||||
* mcp41050 1 256 50
|
||||
* mcp41100 1 256 100
|
||||
* mcp42010 2 256 10
|
||||
* mcp42050 2 256 50
|
||||
* mcp42100 2 256 100
|
||||
*/
|
||||
|
||||
#include <linux/cache.h>
|
||||
#include <linux/err.h>
|
||||
#include <linux/iio/iio.h>
|
||||
#include <linux/iio/types.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/mutex.h>
|
||||
#include <linux/of.h>
|
||||
#include <linux/of_device.h>
|
||||
#include <linux/spi/spi.h>
|
||||
|
||||
#define MCP41010_MAX_WIPERS 2
|
||||
#define MCP41010_WRITE BIT(4)
|
||||
#define MCP41010_WIPER_MAX 255
|
||||
#define MCP41010_WIPER_CHANNEL BIT(0)
|
||||
|
||||
struct mcp41010_cfg {
|
||||
char name[16];
|
||||
int wipers;
|
||||
int kohms;
|
||||
};
|
||||
|
||||
enum mcp41010_type {
|
||||
MCP41010,
|
||||
MCP41050,
|
||||
MCP41100,
|
||||
MCP42010,
|
||||
MCP42050,
|
||||
MCP42100,
|
||||
};
|
||||
|
||||
static const struct mcp41010_cfg mcp41010_cfg[] = {
|
||||
[MCP41010] = { .name = "mcp41010", .wipers = 1, .kohms = 10, },
|
||||
[MCP41050] = { .name = "mcp41050", .wipers = 1, .kohms = 50, },
|
||||
[MCP41100] = { .name = "mcp41100", .wipers = 1, .kohms = 100, },
|
||||
[MCP42010] = { .name = "mcp42010", .wipers = 2, .kohms = 10, },
|
||||
[MCP42050] = { .name = "mcp42050", .wipers = 2, .kohms = 50, },
|
||||
[MCP42100] = { .name = "mcp42100", .wipers = 2, .kohms = 100, },
|
||||
};
|
||||
|
||||
struct mcp41010_data {
|
||||
struct spi_device *spi;
|
||||
const struct mcp41010_cfg *cfg;
|
||||
struct mutex lock; /* Protect write sequences */
|
||||
unsigned int value[MCP41010_MAX_WIPERS]; /* Cache wiper values */
|
||||
u8 buf[2] ____cacheline_aligned;
|
||||
};
|
||||
|
||||
#define MCP41010_CHANNEL(ch) { \
|
||||
.type = IIO_RESISTANCE, \
|
||||
.indexed = 1, \
|
||||
.output = 1, \
|
||||
.channel = (ch), \
|
||||
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
|
||||
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
|
||||
}
|
||||
|
||||
static const struct iio_chan_spec mcp41010_channels[] = {
|
||||
MCP41010_CHANNEL(0),
|
||||
MCP41010_CHANNEL(1),
|
||||
};
|
||||
|
||||
static int mcp41010_read_raw(struct iio_dev *indio_dev,
|
||||
struct iio_chan_spec const *chan,
|
||||
int *val, int *val2, long mask)
|
||||
{
|
||||
struct mcp41010_data *data = iio_priv(indio_dev);
|
||||
int channel = chan->channel;
|
||||
|
||||
switch (mask) {
|
||||
case IIO_CHAN_INFO_RAW:
|
||||
*val = data->value[channel];
|
||||
return IIO_VAL_INT;
|
||||
|
||||
case IIO_CHAN_INFO_SCALE:
|
||||
*val = 1000 * data->cfg->kohms;
|
||||
*val2 = MCP41010_WIPER_MAX;
|
||||
return IIO_VAL_FRACTIONAL;
|
||||
}
|
||||
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
static int mcp41010_write_raw(struct iio_dev *indio_dev,
|
||||
struct iio_chan_spec const *chan,
|
||||
int val, int val2, long mask)
|
||||
{
|
||||
int err;
|
||||
struct mcp41010_data *data = iio_priv(indio_dev);
|
||||
int channel = chan->channel;
|
||||
|
||||
if (mask != IIO_CHAN_INFO_RAW)
|
||||
return -EINVAL;
|
||||
|
||||
if (val > MCP41010_WIPER_MAX || val < 0)
|
||||
return -EINVAL;
|
||||
|
||||
mutex_lock(&data->lock);
|
||||
|
||||
data->buf[0] = MCP41010_WIPER_CHANNEL << channel;
|
||||
data->buf[0] |= MCP41010_WRITE;
|
||||
data->buf[1] = val & 0xff;
|
||||
|
||||
err = spi_write(data->spi, data->buf, sizeof(data->buf));
|
||||
if (!err)
|
||||
data->value[channel] = val;
|
||||
|
||||
mutex_unlock(&data->lock);
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
static const struct iio_info mcp41010_info = {
|
||||
.read_raw = mcp41010_read_raw,
|
||||
.write_raw = mcp41010_write_raw,
|
||||
};
|
||||
|
||||
static int mcp41010_probe(struct spi_device *spi)
|
||||
{
|
||||
int err;
|
||||
struct device *dev = &spi->dev;
|
||||
struct mcp41010_data *data;
|
||||
struct iio_dev *indio_dev;
|
||||
|
||||
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
|
||||
if (!indio_dev)
|
||||
return -ENOMEM;
|
||||
|
||||
data = iio_priv(indio_dev);
|
||||
spi_set_drvdata(spi, indio_dev);
|
||||
data->spi = spi;
|
||||
data->cfg = of_device_get_match_data(&spi->dev);
|
||||
if (!data->cfg)
|
||||
data->cfg = &mcp41010_cfg[spi_get_device_id(spi)->driver_data];
|
||||
|
||||
mutex_init(&data->lock);
|
||||
|
||||
indio_dev->dev.parent = dev;
|
||||
indio_dev->info = &mcp41010_info;
|
||||
indio_dev->channels = mcp41010_channels;
|
||||
indio_dev->num_channels = data->cfg->wipers;
|
||||
indio_dev->name = data->cfg->name;
|
||||
|
||||
err = devm_iio_device_register(dev, indio_dev);
|
||||
if (err)
|
||||
dev_info(&spi->dev, "Unable to register %s\n", indio_dev->name);
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
static const struct of_device_id mcp41010_match[] = {
|
||||
{ .compatible = "microchip,mcp41010", .data = &mcp41010_cfg[MCP41010] },
|
||||
{ .compatible = "microchip,mcp41050", .data = &mcp41010_cfg[MCP41050] },
|
||||
{ .compatible = "microchip,mcp41100", .data = &mcp41010_cfg[MCP41100] },
|
||||
{ .compatible = "microchip,mcp42010", .data = &mcp41010_cfg[MCP42010] },
|
||||
{ .compatible = "microchip,mcp42050", .data = &mcp41010_cfg[MCP42050] },
|
||||
{ .compatible = "microchip,mcp42100", .data = &mcp41010_cfg[MCP42100] },
|
||||
{}
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, mcp41010_match);
|
||||
|
||||
static const struct spi_device_id mcp41010_id[] = {
|
||||
{ "mcp41010", MCP41010 },
|
||||
{ "mcp41050", MCP41050 },
|
||||
{ "mcp41100", MCP41100 },
|
||||
{ "mcp42010", MCP42010 },
|
||||
{ "mcp42050", MCP42050 },
|
||||
{ "mcp42100", MCP42100 },
|
||||
{}
|
||||
};
|
||||
MODULE_DEVICE_TABLE(spi, mcp41010_id);
|
||||
|
||||
static struct spi_driver mcp41010_driver = {
|
||||
.driver = {
|
||||
.name = "mcp41010",
|
||||
.of_match_table = mcp41010_match,
|
||||
},
|
||||
.probe = mcp41010_probe,
|
||||
.id_table = mcp41010_id,
|
||||
};
|
||||
|
||||
module_spi_driver(mcp41010_driver);
|
||||
|
||||
MODULE_AUTHOR("Chris Coffey <cmc@babblebit.net>");
|
||||
MODULE_DESCRIPTION("MCP41010 digital potentiometer");
|
||||
MODULE_LICENSE("GPL v2");
|
||||
Loading…
Reference in New Issue
Block a user