Add dt-bindings and support for Maxim DS3502 into existing ds1803 driver.
DS3502 is a 7 bit Nonvolatile Digital Potentiometer.
Changes since v1:
1. Fixes the alignment to match the open parenthesis in separate patch
2. Adding available functionality for ds1803 driver in separate patch
3. Moving maxim_potentiometer members into ds1803_cfg structure
4. Droping of the INFO_ENABLE channel type
5. Firmware entry with data is used instead of id->driver_data to
to retrieve the chip specific data.
Jagath Jog J (4):
iio: potentiometer: Alignment to match the open parenthesis
iio: potentiometer: Add available functionality
iio: potentiometer: Add support for Maxim DS3502
dt-bindings: iio: potentiometer: Add Maxim DS3502 in trivial-devices
.../devicetree/bindings/trivial-devices.yaml | 2 +
drivers/iio/potentiometer/Kconfig | 6 +-
drivers/iio/potentiometer/ds1803.c | 141 +++++++++++++-----
3 files changed, 106 insertions(+), 43 deletions(-)
--
2.17.1
Maxim DS3502 is a 7 bit nonvolatile digital potentiometer.
Add DS3502 binding into trivial-devices.yaml
Signed-off-by: Jagath Jog J <[email protected]>
---
Documentation/devicetree/bindings/trivial-devices.yaml | 2 ++
1 file changed, 2 insertions(+)
diff --git a/Documentation/devicetree/bindings/trivial-devices.yaml b/Documentation/devicetree/bindings/trivial-devices.yaml
index 091792ba993e..b6187603317a 100644
--- a/Documentation/devicetree/bindings/trivial-devices.yaml
+++ b/Documentation/devicetree/bindings/trivial-devices.yaml
@@ -157,6 +157,8 @@ properties:
- maxim,ds1803-050
# 100 kOhm digital potentiometer with I2C interface
- maxim,ds1803-100
+ # 10 kOhm digital potentiometer with I2C interface
+ - maxim,ds3502
# Low-Power, 4-/12-Channel, 2-Wire Serial, 12-Bit ADCs
- maxim,max1237
# Temperature Sensor, I2C interface
--
2.17.1
On Mon, Feb 14, 2022 at 5:36 AM Jagath Jog J <[email protected]> wrote:
>
> Maxim DS3502 is a 7 bit nonvolatile digital potentiometer.
> Add DS3502 binding into trivial-devices.yaml
Missed grammar period here.
--
With Best Regards,
Andy Shevchenko
The DS3502 is a 7-bit, nonvolatile digital potentiometer featuring
an output voltage range of up to 15.5V.
DS3502 support is implemented into existing ds1803 driver
Datasheet: https://datasheets.maximintegrated.com/en/ds/DS3502.pdf
Signed-off-by: Jagath Jog J <[email protected]>
---
drivers/iio/potentiometer/Kconfig | 6 +-
drivers/iio/potentiometer/ds1803.c | 101 ++++++++++++++++++++---------
2 files changed, 75 insertions(+), 32 deletions(-)
diff --git a/drivers/iio/potentiometer/Kconfig b/drivers/iio/potentiometer/Kconfig
index 832df8da2bc6..cd9aaceb15fe 100644
--- a/drivers/iio/potentiometer/Kconfig
+++ b/drivers/iio/potentiometer/Kconfig
@@ -27,11 +27,11 @@ config AD5272
module will be called ad5272.
config DS1803
- tristate "Maxim Integrated DS1803 Digital Potentiometer driver"
+ tristate "Maxim Integrated DS1803 and similar Digital Potentiometer driver"
depends on I2C
help
- Say yes here to build support for the Maxim Integrated DS1803
- digital potentiometer chip.
+ Say yes here to build support for the Maxim Integrated DS1803 and
+ similar digital potentiometer chip.
To compile this driver as a module, choose M here: the
module will be called ds1803.
diff --git a/drivers/iio/potentiometer/ds1803.c b/drivers/iio/potentiometer/ds1803.c
index bccb9ccac931..0990536e7f36 100644
--- a/drivers/iio/potentiometer/ds1803.c
+++ b/drivers/iio/potentiometer/ds1803.c
@@ -1,12 +1,15 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * Maxim Integrated DS1803 digital potentiometer driver
+ * 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>
@@ -16,44 +19,64 @@
#include <linux/module.h>
#include <linux/mod_devicetable.h>
-#define DS1803_MAX_POS 255
-#define DS1803_WRITE(chan) (0xa8 | ((chan) + 1))
+#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 kohms;
int avail[3];
-};
-
-static const struct ds1803_cfg ds1803_cfg[] = {
- [DS1803_010] = { .avail = { 0, 1, 255 }, .kohms = 10, },
- [DS1803_050] = { .avail = { 0, 1, 255 }, .kohms = 50, },
- [DS1803_100] = { .avail = { 0, 1, 255 }, .kohms = 100, },
+ const struct iio_chan_spec *channels;
+ u8 num_channels;
};
struct ds1803_data {
struct i2c_client *client;
const struct ds1803_cfg *cfg;
+ enum ds1803_type chip_type;
};
-#define DS1803_CHANNEL(ch) { \
+#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_CHANNEL(1),
+ 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 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) },
+ [DS1803_050] = { .wipers = 2, .avail = { 0, 1, 255 }, .kohms = 50,
+ .channels = ds1803_channels,
+ .num_channels = ARRAY_SIZE(ds1803_channels) },
+ [DS1803_100] = { .wipers = 2, .avail = { 0, 1, 255 }, .kohms = 100,
+ .channels = ds1803_channels,
+ .num_channels = ARRAY_SIZE(ds1803_channels) },
+ [DS3502] = { .wipers = 1, .avail = { 0, 1, 127 }, .kohms = 10,
+ .channels = ds3502_channels,
+ .num_channels = ARRAY_SIZE(ds3502_channels) },
};
static int ds1803_read_raw(struct iio_dev *indio_dev,
@@ -67,17 +90,30 @@ static int ds1803_read_raw(struct iio_dev *indio_dev,
switch (mask) {
case IIO_CHAN_INFO_RAW:
- ret = i2c_master_recv(data->client, result,
- indio_dev->num_channels);
- if (ret < 0)
- return ret;
-
- *val = result[pot];
- return IIO_VAL_INT;
+ switch (data->chip_type) {
+ case DS1803_010:
+ case DS1803_050:
+ case DS1803_100:
+ ret = i2c_master_recv(data->client, result,
+ indio_dev->num_channels);
+ if (ret < 0)
+ return ret;
+ *val = result[pot];
+ return IIO_VAL_INT;
+ case DS3502:
+ ret = i2c_smbus_read_byte_data(data->client,
+ chan->address);
+ if (ret < 0)
+ return ret;
+ *val = ret;
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
case IIO_CHAN_INFO_SCALE:
*val = 1000 * data->cfg->kohms;
- *val2 = DS1803_MAX_POS;
+ *val2 = data->cfg->avail[2]; /* Max wiper position */
return IIO_VAL_FRACTIONAL;
}
@@ -89,21 +125,22 @@ static int ds1803_write_raw(struct iio_dev *indio_dev,
int val, int val2, long mask)
{
struct ds1803_data *data = iio_priv(indio_dev);
- int pot = chan->channel;
+ int max_pos = data->cfg->avail[2];
+ u8 addr = chan->address;
if (val2 != 0)
return -EINVAL;
switch (mask) {
case IIO_CHAN_INFO_RAW:
- if (val > DS1803_MAX_POS || val < 0)
+ if (val > max_pos || val < 0)
return -EINVAL;
break;
default:
return -EINVAL;
}
- return i2c_smbus_write_byte_data(data->client, DS1803_WRITE(pot), val);
+ 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,
@@ -142,20 +179,24 @@ static int ds1803_probe(struct i2c_client *client,
data = iio_priv(indio_dev);
data->client = client;
- data->cfg = &ds1803_cfg[id->driver_data];
+ data->chip_type = (uintptr_t)device_get_match_data(dev);
+ if (data->chip_type < DS1803_010 || data->chip_type > DS3502)
+ data->chip_type = id->driver_data;
+ data->cfg = &ds1803_cfg[data->chip_type];
indio_dev->info = &ds1803_info;
- indio_dev->channels = ds1803_channels;
- indio_dev->num_channels = ARRAY_SIZE(ds1803_channels);
+ 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,ds1803-010", .data = (void *)DS1803_010 },
+ { .compatible = "maxim,ds1803-050", .data = (void *)DS1803_050 },
+ { .compatible = "maxim,ds1803-100", .data = (void *)DS1803_100 },
+ { .compatible = "maxim,ds3502", .data = (void *)DS3502 },
{}
};
MODULE_DEVICE_TABLE(of, ds1803_dt_ids);
@@ -164,6 +205,7 @@ 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);
@@ -180,5 +222,6 @@ static struct i2c_driver ds1803_driver = {
module_i2c_driver(ds1803_driver);
MODULE_AUTHOR("Slawomir Stepien <[email protected]>");
+MODULE_AUTHOR("Jagath Jog J <[email protected]>");
MODULE_DESCRIPTION("DS1803 digital potentiometer");
MODULE_LICENSE("GPL v2");
--
2.17.1
Fix following checkpatch.pl check by removing black space
CHECK: Alignment should match open parenthesis
Signed-off-by: Jagath Jog J <[email protected]>
---
drivers/iio/potentiometer/ds1803.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/iio/potentiometer/ds1803.c b/drivers/iio/potentiometer/ds1803.c
index 20b45407eaac..3481dd460525 100644
--- a/drivers/iio/potentiometer/ds1803.c
+++ b/drivers/iio/potentiometer/ds1803.c
@@ -55,8 +55,8 @@ static const struct iio_chan_spec ds1803_channels[] = {
};
static int ds1803_read_raw(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- int *val, int *val2, long mask)
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
{
struct ds1803_data *data = iio_priv(indio_dev);
int pot = chan->channel;
@@ -66,7 +66,7 @@ static int ds1803_read_raw(struct iio_dev *indio_dev,
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = i2c_master_recv(data->client, result,
- indio_dev->num_channels);
+ indio_dev->num_channels);
if (ret < 0)
return ret;
@@ -83,8 +83,8 @@ static int ds1803_read_raw(struct iio_dev *indio_dev,
}
static int ds1803_write_raw(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- int val, int val2, long mask)
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
{
struct ds1803_data *data = iio_priv(indio_dev);
int pot = chan->channel;
@@ -110,7 +110,7 @@ static const struct iio_info ds1803_info = {
};
static int ds1803_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
+ const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
struct ds1803_data *data;
--
2.17.1
On Mon, Feb 14, 2022 at 5:36 AM Jagath Jog J <[email protected]> wrote:
>
> Fix following checkpatch.pl check by removing black space
> CHECK: Alignment should match open parenthesis
I believe in some cases you may make them more compact, like join
lines (it will be slightly longer, but still readable). OTOH, it
depends on the style of the entire driver.
--
With Best Regards,
Andy Shevchenko
Adding available functionality for ds1803 driver which
will show the minimum, step and maximum values
it can accepts through sysfs entry.
Signed-off-by: Jagath Jog J <[email protected]>
---
drivers/iio/potentiometer/ds1803.c | 38 ++++++++++++++++++++++--------
1 file changed, 28 insertions(+), 10 deletions(-)
diff --git a/drivers/iio/potentiometer/ds1803.c b/drivers/iio/potentiometer/ds1803.c
index 3481dd460525..bccb9ccac931 100644
--- a/drivers/iio/potentiometer/ds1803.c
+++ b/drivers/iio/potentiometer/ds1803.c
@@ -27,12 +27,13 @@ enum ds1803_type {
struct ds1803_cfg {
int kohms;
+ int avail[3];
};
static const struct ds1803_cfg ds1803_cfg[] = {
- [DS1803_010] = { .kohms = 10, },
- [DS1803_050] = { .kohms = 50, },
- [DS1803_100] = { .kohms = 100, },
+ [DS1803_010] = { .avail = { 0, 1, 255 }, .kohms = 10, },
+ [DS1803_050] = { .avail = { 0, 1, 255 }, .kohms = 50, },
+ [DS1803_100] = { .avail = { 0, 1, 255 }, .kohms = 100, },
};
struct ds1803_data {
@@ -40,13 +41,14 @@ struct ds1803_data {
const struct ds1803_cfg *cfg;
};
-#define DS1803_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), \
+#define DS1803_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), \
+ .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_RAW), \
}
static const struct iio_chan_spec ds1803_channels[] = {
@@ -104,9 +106,25 @@ static int ds1803_write_raw(struct iio_dev *indio_dev,
return i2c_smbus_write_byte_data(data->client, DS1803_WRITE(pot), 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,
--
2.17.1
On Mon, Feb 14, 2022 at 5:36 AM Jagath Jog J <[email protected]> wrote:
>
> Add dt-bindings and support for Maxim DS3502 into existing ds1803 driver.
> DS3502 is a 7 bit Nonvolatile Digital Potentiometer.
A very good start! A few minor comments to be addressed and one patch
has to be split to at least three.
--
With Best Regards,
Andy Shevchenko
On Mon, 14 Feb 2022 09:06:20 +0530, Jagath Jog J wrote:
> Maxim DS3502 is a 7 bit nonvolatile digital potentiometer.
> Add DS3502 binding into trivial-devices.yaml
>
> Signed-off-by: Jagath Jog J <[email protected]>
> ---
> Documentation/devicetree/bindings/trivial-devices.yaml | 2 ++
> 1 file changed, 2 insertions(+)
>
Please add Acked-by/Reviewed-by tags when posting new versions. However,
there's no need to repost patches *only* to add the tags. The upstream
maintainer will do that for acks received on the version they apply.
If a tag was not added on purpose, please state why and what changed.