On Thu, 8 Mar 2018 20:58:30 +0100 Peter Rosin <peda@xxxxxxxxxx> wrote: > Add support for Microchip digital potentiometers and rheostats > MCP4017, MCP4018, MCP4019 > > They all have one wiper with 128 steps and come in 5, 10, 50 and 100 kOhm > variations. > > Datasheet: http://www.microchip.com/downloads/en/DeviceDoc/22147a.pdf > > Signed-off-by: Peter Rosin <peda@xxxxxxxxxx> Nice little driver. Applied to the togreg branch of iio.git and pushed out as testing for the autobuilders to play with it. Thanks, Jonathan > --- > MAINTAINERS | 3 +- > drivers/iio/potentiometer/Kconfig | 11 ++ > drivers/iio/potentiometer/Makefile | 1 + > drivers/iio/potentiometer/mcp4018.c | 194 ++++++++++++++++++++++++++++++++++++ > 4 files changed, 208 insertions(+), 1 deletion(-) > create mode 100644 drivers/iio/potentiometer/mcp4018.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 4623caf8d72d..81527c75adee 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -8589,11 +8589,12 @@ W: https://linuxtv.org > S: Maintained > F: drivers/media/radio/radio-maxiradio* > > -MCP4531 MICROCHIP DIGITAL POTENTIOMETER DRIVER > +MCP4018 AND MCP4531 MICROCHIP DIGITAL POTENTIOMETER DRIVERS > M: Peter Rosin <peda@xxxxxxxxxx> > L: linux-iio@xxxxxxxxxxxxxxx > S: Maintained > F: Documentation/ABI/testing/sysfs-bus-iio-potentiometer-mcp4531 > +F: drivers/iio/potentiometer/mcp4018.c > F: drivers/iio/potentiometer/mcp4531.c > > MEASUREMENT COMPUTING CIO-DAC IIO DRIVER > diff --git a/drivers/iio/potentiometer/Kconfig b/drivers/iio/potentiometer/Kconfig > index 8bf282510be6..84bdbcd53114 100644 > --- a/drivers/iio/potentiometer/Kconfig > +++ b/drivers/iio/potentiometer/Kconfig > @@ -37,6 +37,17 @@ config MAX5487 > To compile this driver as a module, choose M here: the > module will be called max5487. > > +config MCP4018 > + tristate "Microchip MCP4017/18/19 Digital Potentiometer driver" > + depends on I2Cs > + help > + Say yes here to build support for the Microchip > + MCP4017, MCP4018, MCP4019 > + digital potentiometer chips. > + > + To compile this driver as a module, choose M here: the > + module will be called mcp4018. > + > config MCP4131 > tristate "Microchip MCP413X/414X/415X/416X/423X/424X/425X/426X Digital Potentiometer driver" > depends on SPI > diff --git a/drivers/iio/potentiometer/Makefile b/drivers/iio/potentiometer/Makefile > index 1afd1e70f8cc..0cff8a2916d5 100644 > --- a/drivers/iio/potentiometer/Makefile > +++ b/drivers/iio/potentiometer/Makefile > @@ -7,6 +7,7 @@ > obj-$(CONFIG_DS1803) += ds1803.o > obj-$(CONFIG_MAX5481) += max5481.o > obj-$(CONFIG_MAX5487) += max5487.o > +obj-$(CONFIG_MCP4018) += mcp4018.o > obj-$(CONFIG_MCP4131) += mcp4131.o > obj-$(CONFIG_MCP4531) += mcp4531.o > obj-$(CONFIG_TPL0102) += tpl0102.o > diff --git a/drivers/iio/potentiometer/mcp4018.c b/drivers/iio/potentiometer/mcp4018.c > new file mode 100644 > index 000000000000..601b25d1f387 > --- /dev/null > +++ b/drivers/iio/potentiometer/mcp4018.c > @@ -0,0 +1,194 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Industrial I/O driver for Microchip digital potentiometers > + * Copyright (c) 2018 Axentia Technologies AB > + * Author: Peter Rosin <peda@xxxxxxxxxx> > + * > + * Datasheet: http://www.microchip.com/downloads/en/DeviceDoc/22147a.pdf > + * > + * DEVID #Wipers #Positions Resistor Opts (kOhm) > + * mcp4017 1 128 5, 10, 50, 100 > + * mcp4018 1 128 5, 10, 50, 100 > + * mcp4019 1 128 5, 10, 50, 100 > + */ > + > +#include <linux/err.h> > +#include <linux/i2c.h> > +#include <linux/iio/iio.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/of_device.h> > + > +#define MCP4018_WIPER_MAX 127 > + > +struct mcp4018_cfg { > + int kohms; > +}; > + > +enum mcp4018_type { > + MCP4018_502, > + MCP4018_103, > + MCP4018_503, > + MCP4018_104, > +}; > + > +static const struct mcp4018_cfg mcp4018_cfg[] = { > + [MCP4018_502] = { .kohms = 5, }, > + [MCP4018_103] = { .kohms = 10, }, > + [MCP4018_503] = { .kohms = 50, }, > + [MCP4018_104] = { .kohms = 100, }, > +}; > + > +struct mcp4018_data { > + struct i2c_client *client; > + const struct mcp4018_cfg *cfg; > +}; > + > +static const struct iio_chan_spec mcp4018_channel = { > + .type = IIO_RESISTANCE, > + .indexed = 1, > + .output = 1, > + .channel = 0, > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), > +}; > + > +static int mcp4018_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, long mask) > +{ > + struct mcp4018_data *data = iio_priv(indio_dev); > + s32 ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + ret = i2c_smbus_read_byte(data->client); > + if (ret < 0) > + return ret; > + *val = ret; > + return IIO_VAL_INT; > + case IIO_CHAN_INFO_SCALE: > + *val = 1000 * data->cfg->kohms; > + *val2 = MCP4018_WIPER_MAX; > + return IIO_VAL_FRACTIONAL; > + } > + > + return -EINVAL; > +} > + > +static int mcp4018_write_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int val, int val2, long mask) > +{ > + struct mcp4018_data *data = iio_priv(indio_dev); > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + if (val > MCP4018_WIPER_MAX || val < 0) > + return -EINVAL; > + break; > + default: > + return -EINVAL; > + } > + > + return i2c_smbus_write_byte(data->client, val); > +} > + > +static const struct iio_info mcp4018_info = { > + .read_raw = mcp4018_read_raw, > + .write_raw = mcp4018_write_raw, > +}; > + > +#ifdef CONFIG_OF > + > +#define MCP4018_COMPATIBLE(of_compatible, cfg) { \ > + .compatible = of_compatible, \ > + .data = &mcp4018_cfg[cfg], \ > +} > + > +static const struct of_device_id mcp4018_of_match[] = { > + MCP4018_COMPATIBLE("microchip,mcp4017-502", MCP4018_502), > + MCP4018_COMPATIBLE("microchip,mcp4017-103", MCP4018_103), > + MCP4018_COMPATIBLE("microchip,mcp4017-503", MCP4018_503), > + MCP4018_COMPATIBLE("microchip,mcp4017-104", MCP4018_104), > + MCP4018_COMPATIBLE("microchip,mcp4018-502", MCP4018_502), > + MCP4018_COMPATIBLE("microchip,mcp4018-103", MCP4018_103), > + MCP4018_COMPATIBLE("microchip,mcp4018-503", MCP4018_503), > + MCP4018_COMPATIBLE("microchip,mcp4018-104", MCP4018_104), > + MCP4018_COMPATIBLE("microchip,mcp4019-502", MCP4018_502), > + MCP4018_COMPATIBLE("microchip,mcp4019-103", MCP4018_103), > + MCP4018_COMPATIBLE("microchip,mcp4019-503", MCP4018_503), > + MCP4018_COMPATIBLE("microchip,mcp4019-104", MCP4018_104), > + { /* sentinel */ } > +}; > +MODULE_DEVICE_TABLE(of, mcp4018_of_match); > + > +#endif > + > +static int mcp4018_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + struct device *dev = &client->dev; > + struct mcp4018_data *data; > + struct iio_dev *indio_dev; > + const struct of_device_id *match; > + > + if (!i2c_check_functionality(client->adapter, > + I2C_FUNC_SMBUS_BYTE)) { > + dev_err(dev, "SMBUS Byte transfers not supported\n"); > + return -EOPNOTSUPP; > + } > + > + 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; > + > + match = of_match_device(of_match_ptr(mcp4018_of_match), dev); > + if (match) > + data->cfg = of_device_get_match_data(dev); > + else > + data->cfg = &mcp4018_cfg[id->driver_data]; > + > + indio_dev->dev.parent = dev; > + indio_dev->info = &mcp4018_info; > + indio_dev->channels = &mcp4018_channel; > + indio_dev->num_channels = 1; > + indio_dev->name = client->name; > + > + return devm_iio_device_register(dev, indio_dev); > +} > + > +static const struct i2c_device_id mcp4018_id[] = { > + { "mcp4017-502", MCP4018_502 }, > + { "mcp4017-103", MCP4018_103 }, > + { "mcp4017-503", MCP4018_503 }, > + { "mcp4017-104", MCP4018_104 }, > + { "mcp4018-502", MCP4018_502 }, > + { "mcp4018-103", MCP4018_103 }, > + { "mcp4018-503", MCP4018_503 }, > + { "mcp4018-104", MCP4018_104 }, > + { "mcp4019-502", MCP4018_502 }, > + { "mcp4019-103", MCP4018_103 }, > + { "mcp4019-503", MCP4018_503 }, > + { "mcp4019-104", MCP4018_104 }, > + {} > +}; > +MODULE_DEVICE_TABLE(i2c, mcp4018_id); > + > +static struct i2c_driver mcp4018_driver = { > + .driver = { > + .name = "mcp4018", > + .of_match_table = of_match_ptr(mcp4018_of_match), > + }, > + .probe = mcp4018_probe, > + .id_table = mcp4018_id, > +}; > + > +module_i2c_driver(mcp4018_driver); > + > +MODULE_AUTHOR("Peter Rosin <peda@xxxxxxxxxx>"); > +MODULE_DESCRIPTION("MCP4018 digital potentiometer"); > +MODULE_LICENSE("GPL"); -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
