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-rw-r--r--MAINTAINERS3
-rw-r--r--drivers/iio/potentiometer/Kconfig11
-rw-r--r--drivers/iio/potentiometer/Makefile1
-rw-r--r--drivers/iio/potentiometer/mcp4018.c194
4 files changed, 208 insertions, 1 deletions
diff --git a/MAINTAINERS b/MAINTAINERS
index 885d20072d97..36f1442a9aae 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8586,11 +8586,12 @@ 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@axentia.se>
L: linux-iio@vger.kernel.org
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 8daf6d1f4e05..79ec2eba4969 100644
--- a/drivers/iio/potentiometer/Kconfig
+++ b/drivers/iio/potentiometer/Kconfig
@@ -47,6 +47,17 @@ 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 I2C
+ 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 dbc139cec376..4af657883c3f 100644
--- a/drivers/iio/potentiometer/Makefile
+++ b/drivers/iio/potentiometer/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_AD5272) += ad5272.o
obj-$(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@axentia.se>
+ *
+ * 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@axentia.se>");
+MODULE_DESCRIPTION("MCP4018 digital potentiometer");
+MODULE_LICENSE("GPL");