Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 264 insertions, 0 deletions

diff --git a/drivers/iio/potentiometer/ds1803.c b/drivers/iio/potentiometer/ds1803.c
new file mode 100644
index 0000000000..fc183e0790
--- /dev/null
+++ b/drivers/iio/potentiometer/ds1803.c
@@ -0,0 +1,264 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Maxim Integrated DS1803 and similar digital potentiometer driver
+ * Copyright (c) 2016 Slawomir Stepien
+ * Copyright (c) 2022 Jagath Jog J
+ *
+ * Datasheet: https://datasheets.maximintegrated.com/en/ds/DS1803.pdf
+ * Datasheet: https://datasheets.maximintegrated.com/en/ds/DS3502.pdf
+ *
+ * DEVID	#Wipers	#Positions	Resistor Opts (kOhm)	i2c address
+ * ds1803	2	256		10, 50, 100		0101xxx
+ * ds3502	1	128		10			01010xx
+ */
+
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/property.h>
+
+#define DS1803_WIPER_0         0xA9
+#define DS1803_WIPER_1         0xAA
+#define DS3502_WR_IVR          0x00
+
+enum ds1803_type {
+	DS1803_010,
+	DS1803_050,
+	DS1803_100,
+	DS3502,
+};
+
+struct ds1803_cfg {
+	int wipers;
+	int avail[3];
+	int kohms;
+	const struct iio_chan_spec *channels;
+	u8 num_channels;
+	int (*read)(struct iio_dev *indio_dev,
+		    struct iio_chan_spec const *chan, int *val);
+};
+
+struct ds1803_data {
+	struct i2c_client *client;
+	const struct ds1803_cfg *cfg;
+};
+
+#define DS1803_CHANNEL(ch, addr) {					\
+	.type = IIO_RESISTANCE,						\
+	.indexed = 1,							\
+	.output = 1,							\
+	.channel = (ch),						\
+	.address = (addr),						\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
+	.info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_RAW),   \
+}
+
+static const struct iio_chan_spec ds1803_channels[] = {
+	DS1803_CHANNEL(0, DS1803_WIPER_0),
+	DS1803_CHANNEL(1, DS1803_WIPER_1),
+};
+
+static const struct iio_chan_spec ds3502_channels[] = {
+	DS1803_CHANNEL(0, DS3502_WR_IVR),
+};
+
+static int ds1803_read(struct iio_dev *indio_dev,
+		       struct iio_chan_spec const *chan,
+		       int *val)
+{
+	struct ds1803_data *data = iio_priv(indio_dev);
+	int ret;
+	u8 result[ARRAY_SIZE(ds1803_channels)];
+
+	ret = i2c_master_recv(data->client, result, indio_dev->num_channels);
+	if (ret < 0)
+		return ret;
+
+	*val = result[chan->channel];
+	return ret;
+}
+
+static int ds3502_read(struct iio_dev *indio_dev,
+		       struct iio_chan_spec const *chan,
+		       int *val)
+{
+	struct ds1803_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, chan->address);
+	if (ret < 0)
+		return ret;
+
+	*val = ret;
+	return ret;
+}
+
+static const struct ds1803_cfg ds1803_cfg[] = {
+	[DS1803_010] = {
+		.wipers = 2,
+		.avail = { 0, 1, 255 },
+		.kohms =  10,
+		.channels = ds1803_channels,
+		.num_channels = ARRAY_SIZE(ds1803_channels),
+		.read = ds1803_read,
+	},
+	[DS1803_050] = {
+		.wipers = 2,
+		.avail = { 0, 1, 255 },
+		.kohms =  50,
+		.channels = ds1803_channels,
+		.num_channels = ARRAY_SIZE(ds1803_channels),
+		.read = ds1803_read,
+	},
+	[DS1803_100] = {
+		.wipers = 2,
+		.avail = { 0, 1, 255 },
+		.kohms = 100,
+		.channels = ds1803_channels,
+		.num_channels = ARRAY_SIZE(ds1803_channels),
+		.read = ds1803_read,
+	},
+	[DS3502] = {
+	  .wipers = 1,
+	  .avail = { 0, 1, 127 },
+	  .kohms =  10,
+	  .channels = ds3502_channels,
+	  .num_channels = ARRAY_SIZE(ds3502_channels),
+	  .read = ds3502_read,
+	},
+};
+
+static int ds1803_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val, int *val2, long mask)
+{
+	struct ds1803_data *data = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		ret = data->cfg->read(indio_dev, chan, val);
+		if (ret < 0)
+			return ret;
+
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SCALE:
+		*val = 1000 * data->cfg->kohms;
+		*val2 = data->cfg->avail[2]; /* Max wiper position */
+		return IIO_VAL_FRACTIONAL;
+	}
+
+	return -EINVAL;
+}
+
+static int ds1803_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val, int val2, long mask)
+{
+	struct ds1803_data *data = iio_priv(indio_dev);
+	u8 addr = chan->address;
+	int max_pos = data->cfg->avail[2];
+
+	if (val2 != 0)
+		return -EINVAL;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		if (val > max_pos || val < 0)
+			return -EINVAL;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return i2c_smbus_write_byte_data(data->client, addr, val);
+}
+
+static int ds1803_read_avail(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     const int **vals, int *type,
+			     int *length, long mask)
+{
+	struct ds1803_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		*vals = data->cfg->avail;
+		*length = ARRAY_SIZE(data->cfg->avail);
+		*type = IIO_VAL_INT;
+		return IIO_AVAIL_RANGE;
+	}
+	return -EINVAL;
+}
+
+static const struct iio_info ds1803_info = {
+	.read_raw = ds1803_read_raw,
+	.write_raw = ds1803_write_raw,
+	.read_avail = ds1803_read_avail,
+};
+
+static int ds1803_probe(struct i2c_client *client)
+{
+	const struct i2c_device_id *id = i2c_client_get_device_id(client);
+	struct device *dev = &client->dev;
+	struct ds1803_data *data;
+	struct iio_dev *indio_dev;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	i2c_set_clientdata(client, indio_dev);
+
+	data = iio_priv(indio_dev);
+	data->client = client;
+	data->cfg = device_get_match_data(dev);
+	if (!data->cfg)
+		data->cfg = &ds1803_cfg[id->driver_data];
+
+	indio_dev->info = &ds1803_info;
+	indio_dev->channels = data->cfg->channels;
+	indio_dev->num_channels = data->cfg->num_channels;
+	indio_dev->name = client->name;
+
+	return devm_iio_device_register(dev, indio_dev);
+}
+
+static const struct of_device_id ds1803_dt_ids[] = {
+	{ .compatible = "maxim,ds1803-010", .data = &ds1803_cfg[DS1803_010] },
+	{ .compatible = "maxim,ds1803-050", .data = &ds1803_cfg[DS1803_050] },
+	{ .compatible = "maxim,ds1803-100", .data = &ds1803_cfg[DS1803_100] },
+	{ .compatible = "maxim,ds3502", .data = &ds1803_cfg[DS3502] },
+	{}
+};
+MODULE_DEVICE_TABLE(of, ds1803_dt_ids);
+
+static const struct i2c_device_id ds1803_id[] = {
+	{ "ds1803-010", DS1803_010 },
+	{ "ds1803-050", DS1803_050 },
+	{ "ds1803-100", DS1803_100 },
+	{ "ds3502", DS3502 },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, ds1803_id);
+
+static struct i2c_driver ds1803_driver = {
+	.driver = {
+		.name	= "ds1803",
+		.of_match_table = ds1803_dt_ids,
+	},
+	.probe		= ds1803_probe,
+	.id_table	= ds1803_id,
+};
+
+module_i2c_driver(ds1803_driver);
+
+MODULE_AUTHOR("Slawomir Stepien <sst@poczta.fm>");
+MODULE_AUTHOR("Jagath Jog J <jagathjog1996@gmail.com>");
+MODULE_DESCRIPTION("DS1803 digital potentiometer");
+MODULE_LICENSE("GPL v2");