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 | 4 +- drivers/iio/potentiometer/ds1803.c | 150 +++++++++++++++++++++++------ 2 files changed, 120 insertions(+), 34 deletions(-) diff --git a/drivers/iio/potentiometer/Kconfig b/drivers/iio/potentiometer/Kconfig index 832df8da2bc6..1741af33672c 100644 --- a/drivers/iio/potentiometer/Kconfig +++ b/drivers/iio/potentiometer/Kconfig @@ -27,10 +27,10 @@ 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 + Say yes here to build support for the Maxim Integrated DS1803 and DS3502 digital potentiometer chip. To compile this driver as a module, choose M here: the diff --git a/drivers/iio/potentiometer/ds1803.c b/drivers/iio/potentiometer/ds1803.c index 20b45407eaac..5e403e3400f7 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 DS3502 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> @@ -16,47 +19,88 @@ #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) +#define DS3502_CR (0x02) +#define DS3502_MODE0 (0x00) +#define DS3502_MODE1 (0x80) enum ds1803_type { DS1803_010, DS1803_050, DS1803_100, + DS3502, }; struct ds1803_cfg { + int wipers; + int avail[3]; int kohms; }; static const struct ds1803_cfg ds1803_cfg[] = { - [DS1803_010] = { .kohms = 10, }, - [DS1803_050] = { .kohms = 50, }, - [DS1803_100] = { .kohms = 100, }, + [DS1803_010] = { .wipers = 2, .avail = { 0, 1, 255 }, .kohms = 10, }, + [DS1803_050] = { .wipers = 2, .avail = { 0, 1, 255 }, .kohms = 50, }, + [DS1803_100] = { .wipers = 2, .avail = { 0, 1, 255 }, .kohms = 100, }, + [DS3502] = { .wipers = 1, .avail = { 0, 1, 127 }, .kohms = 10, }, +}; + +struct maxim_potentiometer { + const struct iio_chan_spec *channels; + u8 num_channels; }; struct ds1803_data { struct i2c_client *client; + enum ds1803_type chip_type; const struct ds1803_cfg *cfg; + const struct maxim_potentiometer *chip; }; -#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, 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[] = { + { + .type = IIO_RESISTANCE, + .indexed = 1, + .output = 1, + .channel = 0, + .address = (DS3502_WR_IVR), + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_ENABLE), + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), + .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_RAW), + }, +}; + +static const struct maxim_potentiometer maxim_potentiometer_chips[] = { + [DS1803_100] = { + .channels = ds1803_channels, + .num_channels = ARRAY_SIZE(ds1803_channels), + }, + [DS3502] = { + .channels = ds3502_channels, + .num_channels = ARRAY_SIZE(ds3502_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; @@ -65,17 +109,28 @@ 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); + switch (data->chip_type) { + case DS1803_010: + case DS1803_050: + case DS1803_100: + ret = i2c_master_recv(data->client, result, + indio_dev->num_channels); + *val = result[pot]; + break; + case DS3502: + ret = i2c_smbus_read_byte_data(data->client, chan->address); + *val = ret; + break; + default: + return -EINVAL; + } + if (ret < 0) return ret; - - *val = result[pot]; return IIO_VAL_INT; - case IIO_CHAN_INFO_SCALE: *val = 1000 * data->cfg->kohms; - *val2 = DS1803_MAX_POS; + *val2 = data->cfg->avail[2]; return IIO_VAL_FRACTIONAL; } @@ -83,38 +138,64 @@ 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; + 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; + case IIO_CHAN_INFO_ENABLE: + if (val == 1) + val = DS3502_MODE1; + else if (val != DS3502_MODE0) return -EINVAL; + addr = DS3502_CR; 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, + 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, + .read_avail = ds1803_read_avail, .write_raw = ds1803_write_raw, }; 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; struct iio_dev *indio_dev; + enum ds1803_type chip_type = (id->driver_data <= DS1803_100 ? DS1803_100 : DS3502); + const struct maxim_potentiometer *chip = &maxim_potentiometer_chips[chip_type]; indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); if (!indio_dev) @@ -125,10 +206,12 @@ 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 = chip; + data->chip_type = chip_type; indio_dev->info = &ds1803_info; - indio_dev->channels = ds1803_channels; - indio_dev->num_channels = ARRAY_SIZE(ds1803_channels); + indio_dev->channels = chip->channels; + indio_dev->num_channels = chip->num_channels; indio_dev->name = client->name; return devm_iio_device_register(dev, indio_dev); @@ -138,6 +221,7 @@ 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); @@ -146,6 +230,7 @@ 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); @@ -162,5 +247,6 @@ static struct i2c_driver ds1803_driver = { module_i2c_driver(ds1803_driver); MODULE_AUTHOR("Slawomir Stepien <sst@xxxxxxxxx>"); -MODULE_DESCRIPTION("DS1803 digital potentiometer"); +MODULE_AUTHOR("Jagath Jog J <jagathjog1996@xxxxxxxxx>"); +MODULE_DESCRIPTION("DS1803 and DS3502 digital potentiometer"); MODULE_LICENSE("GPL v2"); -- 2.17.1
