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 <jagathjog1996@xxxxxxxxx> --- 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 <sst@xxxxxxxxx>"); +MODULE_AUTHOR("Jagath Jog J <jagathjog1996@xxxxxxxxx>"); MODULE_DESCRIPTION("DS1803 digital potentiometer"); MODULE_LICENSE("GPL v2"); -- 2.17.1
