| Message ID | 20221106165928.223318-1-angelo.dureghello@timesys.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [v3] iio: dac: add support for max5522 | expand |
On Sun, 6 Nov 2022 17:59:28 +0100 Angelo Dureghello <angelo.dureghello@timesys.com> wrote: > Add initial support for DAC max5522. > > Tested writing DAC A and B with some values, > from 0 to 1023, measured output voltages, driver works properly. > > Additions for max5523/24/25 will follow. > > Signed-off-by: Angelo Dureghello <angelo.dureghello@timesys.com> I've been dozy up to now. This needs a (fairly simple) device tree binding doc in Documentation/devicetree/bindings/iio/dac/ Make sure to include the device tree binding maintainers on that and to follow the instructions to test the binding. Feel free to send as a separate patch but refer back to this one. I'll hold off applying this just in case it needs any changes resulting form the binding review. > > --- > Changes for v.2 > - fix commit message > - Kconfig, fix depends and select > - Kconfig, fix typo > - fix include alphabetical order > - remove sysfs includes > - fix MAX5522_REG_DATA macro > - use devm_ as much as possible > - add regulator_enable > - remove useless code > - remove commas after structure initializers and null terminators > - change to use simplier module_spi_driver > - get id->name from device info structure > - regulator voltage read always from read_raw (no cache) > > Changes for v.3 > - move signed-off to be before the changelog > - re-fix include alphabetical order > - remove vrefin_mv references > - align function params with opening bracket > - try to get chip_info from firmware > - name always read from max5522_chip_info_tbl > - remove line break before MODULE_DEVICE_TABLE > --- > drivers/iio/dac/Kconfig | 13 +++ > drivers/iio/dac/Makefile | 1 + > drivers/iio/dac/max5522.c | 207 ++++++++++++++++++++++++++++++++++++++ > 3 files changed, 221 insertions(+) > create mode 100644 drivers/iio/dac/max5522.c > > diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig > index 80521bd28d0f..6c49523fe357 100644 > --- a/drivers/iio/dac/Kconfig > +++ b/drivers/iio/dac/Kconfig > @@ -357,6 +357,19 @@ config MAX517 > This driver can also be built as a module. If so, the module > will be called max517. > > +config MAX5522 > + tristate "Maxim MAX5522 DAC driver" > + depends on SPI_MASTER > + select REGMAP_SPI > + help > + Say Y here if you want to build a driver for the Maxim MAX5522. > + > + MAX5522 is a dual, ultra-low-power, 10-Bit, voltage-output > + digital to analog converter (DAC) offering rail-to-rail buffered > + voltage outputs. > + > + If compiled as a module, it will be called max5522. > + > config MAX5821 > tristate "Maxim MAX5821 DAC driver" > depends on I2C > diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile > index ec3e42713f00..6c74fea21736 100644 > --- a/drivers/iio/dac/Makefile > +++ b/drivers/iio/dac/Makefile > @@ -38,6 +38,7 @@ obj-$(CONFIG_LTC2632) += ltc2632.o > obj-$(CONFIG_LTC2688) += ltc2688.o > obj-$(CONFIG_M62332) += m62332.o > obj-$(CONFIG_MAX517) += max517.o > +obj-$(CONFIG_MAX5522) += max5522.o > obj-$(CONFIG_MAX5821) += max5821.o > obj-$(CONFIG_MCP4725) += mcp4725.o > obj-$(CONFIG_MCP4922) += mcp4922.o > diff --git a/drivers/iio/dac/max5522.c b/drivers/iio/dac/max5522.c > new file mode 100644 > index 000000000000..00ba4e98fb9c > --- /dev/null > +++ b/drivers/iio/dac/max5522.c > @@ -0,0 +1,207 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Maxim MAX5522 > + * Dual, Ultra-Low-Power 10-Bit, Voltage-Output DACs > + * > + * Copyright 2022 Timesys Corp. > + */ > + > +#include <linux/device.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/mod_devicetable.h> > +#include <linux/regmap.h> > +#include <linux/regulator/consumer.h> > +#include <linux/slab.h> > +#include <linux/spi/spi.h> > + > +#include <linux/iio/iio.h> > + > +#define MAX5522_MAX_ADDR 15 > +#define MAX5522_CTRL_NONE 0 > +#define MAX5522_CTRL_LOAD_IN_A 9 > +#define MAX5522_CTRL_LOAD_IN_B 10 > + > +#define MAX5522_REG_DATA(x) ((x) + MAX5522_CTRL_LOAD_IN_A) > + > +struct max5522_chip_info { > + const char *name; > + const struct iio_chan_spec *channels; > + unsigned int num_channels; > +}; > + > +struct max5522_state { > + struct regmap *regmap; > + const struct max5522_chip_info *chip_info; > + unsigned short dac_cache[2]; > + struct regulator *vrefin_reg; > +}; > + > +#define MAX5522_CHANNEL(chan) { \ > + .type = IIO_VOLTAGE, \ > + .indexed = 1, \ > + .output = 1, \ > + .channel = chan, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ > + BIT(IIO_CHAN_INFO_SCALE), \ > + .scan_type = { \ > + .sign = 'u', \ > + .realbits = 10, \ > + .storagebits = 16, \ > + .shift = 2, \ > + } \ > +} > + > +const struct iio_chan_spec max5522_channels[] = { > + MAX5522_CHANNEL(0), > + MAX5522_CHANNEL(1), > +}; > + > +enum max5522_type { > + ID_MAX5522, > +}; > + > +static const struct max5522_chip_info max5522_chip_info_tbl[] = { > + [ID_MAX5522] = { > + .name = "max5522", > + .channels = max5522_channels, > + .num_channels = 2, > + }, > +}; > + > +static inline int max5522_info_to_reg(struct iio_chan_spec const *chan) > +{ > + return MAX5522_REG_DATA(chan->channel); > +} > + > +static int max5522_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, long info) > +{ > + struct max5522_state *state = iio_priv(indio_dev); > + int ret; > + > + switch (info) { > + case IIO_CHAN_INFO_RAW: > + *val = state->dac_cache[chan->channel]; > + return IIO_VAL_INT; > + case IIO_CHAN_INFO_SCALE: > + ret = regulator_get_voltage(state->vrefin_reg); > + if (ret < 0) > + return -EINVAL; > + *val = ret / 1000; > + *val2 = 10; > + return IIO_VAL_FRACTIONAL_LOG2; > + default: > + return -EINVAL; > + } > + > + return -EINVAL; > +} > + > +static int max5522_write_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int val, int val2, long info) > +{ > + struct max5522_state *state = iio_priv(indio_dev); > + int rval; > + > + if (val > 1023 || val < 0) > + return -EINVAL; > + > + rval = regmap_write(state->regmap, max5522_info_to_reg(chan), > + val << chan->scan_type.shift); > + if (rval < 0) > + return rval; > + > + state->dac_cache[chan->channel] = val; > + > + return 0; > +} > + > +static const struct iio_info max5522_info = { > + .read_raw = max5522_read_raw, > + .write_raw = max5522_write_raw, > +}; > + > +static const struct regmap_config max5522_regmap_config = { > + .reg_bits = 4, > + .val_bits = 12, > + .max_register = MAX5522_MAX_ADDR, > +}; > + > +static int max5522_spi_probe(struct spi_device *spi) > +{ > + const struct spi_device_id *id = spi_get_device_id(spi); > + struct iio_dev *indio_dev; > + struct max5522_state *state; > + int ret; > + > + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*state)); > + if (indio_dev == NULL) { > + dev_err(&spi->dev, "failed to allocate iio device\n"); > + return -ENOMEM; > + } > + > + state = iio_priv(indio_dev); > + state->chip_info = device_get_match_data(&spi->dev); > + if (!state->chip_info) { > + state->chip_info = > + (struct max5522_chip_info *)(id->driver_data); > + if (!state->chip_info) > + return -EINVAL; > + } > + > + state->vrefin_reg = devm_regulator_get(&spi->dev, "vrefin"); > + if (IS_ERR(state->vrefin_reg)) > + return dev_err_probe(&spi->dev, PTR_ERR(state->vrefin_reg), > + "Vrefin regulator not specified\n"); > + > + ret = regulator_enable(state->vrefin_reg); > + if (ret) { > + return dev_err_probe(&spi->dev, ret, > + "Failed to enable vref regulators\n"); > + } > + > + state->regmap = devm_regmap_init_spi(spi, &max5522_regmap_config); > + > + if (IS_ERR(state->regmap)) > + return PTR_ERR(state->regmap); > + > + indio_dev->info = &max5522_info; > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->channels = max5522_channels; > + indio_dev->num_channels = ARRAY_SIZE(max5522_channels); > + indio_dev->name = max5522_chip_info_tbl[ID_MAX5522].name; > + > + return devm_iio_device_register(&spi->dev, indio_dev); > +} > + > +static const struct spi_device_id max5522_ids[] = { > + { "max5522", (kernel_ulong_t)&max5522_chip_info_tbl[ID_MAX5522] }, > + {} > +}; > +MODULE_DEVICE_TABLE(spi, max5522_ids); > + > +static const struct of_device_id max5522_of_match[] = { > + { > + .compatible = "maxim,max5522", > + .data = &max5522_chip_info_tbl[ID_MAX5522], > + }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, max5522_of_match); > + > +static struct spi_driver max5522_spi_driver = { > + .driver = { > + .name = "max5522", > + .of_match_table = max5522_of_match, > + }, > + .probe = max5522_spi_probe, > + .id_table = max5522_ids, > +}; > +module_spi_driver(max5522_spi_driver); > + > +MODULE_AUTHOR("Angelo Dureghello <angelo.dureghello@timesys.com"); > +MODULE_DESCRIPTION("MAX5522 DAC driver"); > +MODULE_LICENSE("GPL");
diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig index 80521bd28d0f..6c49523fe357 100644 --- a/drivers/iio/dac/Kconfig +++ b/drivers/iio/dac/Kconfig @@ -357,6 +357,19 @@ config MAX517 This driver can also be built as a module. If so, the module will be called max517. +config MAX5522 + tristate "Maxim MAX5522 DAC driver" + depends on SPI_MASTER + select REGMAP_SPI + help + Say Y here if you want to build a driver for the Maxim MAX5522. + + MAX5522 is a dual, ultra-low-power, 10-Bit, voltage-output + digital to analog converter (DAC) offering rail-to-rail buffered + voltage outputs. + + If compiled as a module, it will be called max5522. + config MAX5821 tristate "Maxim MAX5821 DAC driver" depends on I2C diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile index ec3e42713f00..6c74fea21736 100644 --- a/drivers/iio/dac/Makefile +++ b/drivers/iio/dac/Makefile @@ -38,6 +38,7 @@ obj-$(CONFIG_LTC2632) += ltc2632.o obj-$(CONFIG_LTC2688) += ltc2688.o obj-$(CONFIG_M62332) += m62332.o obj-$(CONFIG_MAX517) += max517.o +obj-$(CONFIG_MAX5522) += max5522.o obj-$(CONFIG_MAX5821) += max5821.o obj-$(CONFIG_MCP4725) += mcp4725.o obj-$(CONFIG_MCP4922) += mcp4922.o diff --git a/drivers/iio/dac/max5522.c b/drivers/iio/dac/max5522.c new file mode 100644 index 000000000000..00ba4e98fb9c --- /dev/null +++ b/drivers/iio/dac/max5522.c @@ -0,0 +1,207 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Maxim MAX5522 + * Dual, Ultra-Low-Power 10-Bit, Voltage-Output DACs + * + * Copyright 2022 Timesys Corp. + */ + +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> +#include <linux/slab.h> +#include <linux/spi/spi.h> + +#include <linux/iio/iio.h> + +#define MAX5522_MAX_ADDR 15 +#define MAX5522_CTRL_NONE 0 +#define MAX5522_CTRL_LOAD_IN_A 9 +#define MAX5522_CTRL_LOAD_IN_B 10 + +#define MAX5522_REG_DATA(x) ((x) + MAX5522_CTRL_LOAD_IN_A) + +struct max5522_chip_info { + const char *name; + const struct iio_chan_spec *channels; + unsigned int num_channels; +}; + +struct max5522_state { + struct regmap *regmap; + const struct max5522_chip_info *chip_info; + unsigned short dac_cache[2]; + struct regulator *vrefin_reg; +}; + +#define MAX5522_CHANNEL(chan) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .output = 1, \ + .channel = chan, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_SCALE), \ + .scan_type = { \ + .sign = 'u', \ + .realbits = 10, \ + .storagebits = 16, \ + .shift = 2, \ + } \ +} + +const struct iio_chan_spec max5522_channels[] = { + MAX5522_CHANNEL(0), + MAX5522_CHANNEL(1), +}; + +enum max5522_type { + ID_MAX5522, +}; + +static const struct max5522_chip_info max5522_chip_info_tbl[] = { + [ID_MAX5522] = { + .name = "max5522", + .channels = max5522_channels, + .num_channels = 2, + }, +}; + +static inline int max5522_info_to_reg(struct iio_chan_spec const *chan) +{ + return MAX5522_REG_DATA(chan->channel); +} + +static int max5522_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long info) +{ + struct max5522_state *state = iio_priv(indio_dev); + int ret; + + switch (info) { + case IIO_CHAN_INFO_RAW: + *val = state->dac_cache[chan->channel]; + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + ret = regulator_get_voltage(state->vrefin_reg); + if (ret < 0) + return -EINVAL; + *val = ret / 1000; + *val2 = 10; + return IIO_VAL_FRACTIONAL_LOG2; + default: + return -EINVAL; + } + + return -EINVAL; +} + +static int max5522_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long info) +{ + struct max5522_state *state = iio_priv(indio_dev); + int rval; + + if (val > 1023 || val < 0) + return -EINVAL; + + rval = regmap_write(state->regmap, max5522_info_to_reg(chan), + val << chan->scan_type.shift); + if (rval < 0) + return rval; + + state->dac_cache[chan->channel] = val; + + return 0; +} + +static const struct iio_info max5522_info = { + .read_raw = max5522_read_raw, + .write_raw = max5522_write_raw, +}; + +static const struct regmap_config max5522_regmap_config = { + .reg_bits = 4, + .val_bits = 12, + .max_register = MAX5522_MAX_ADDR, +}; + +static int max5522_spi_probe(struct spi_device *spi) +{ + const struct spi_device_id *id = spi_get_device_id(spi); + struct iio_dev *indio_dev; + struct max5522_state *state; + int ret; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*state)); + if (indio_dev == NULL) { + dev_err(&spi->dev, "failed to allocate iio device\n"); + return -ENOMEM; + } + + state = iio_priv(indio_dev); + state->chip_info = device_get_match_data(&spi->dev); + if (!state->chip_info) { + state->chip_info = + (struct max5522_chip_info *)(id->driver_data); + if (!state->chip_info) + return -EINVAL; + } + + state->vrefin_reg = devm_regulator_get(&spi->dev, "vrefin"); + if (IS_ERR(state->vrefin_reg)) + return dev_err_probe(&spi->dev, PTR_ERR(state->vrefin_reg), + "Vrefin regulator not specified\n"); + + ret = regulator_enable(state->vrefin_reg); + if (ret) { + return dev_err_probe(&spi->dev, ret, + "Failed to enable vref regulators\n"); + } + + state->regmap = devm_regmap_init_spi(spi, &max5522_regmap_config); + + if (IS_ERR(state->regmap)) + return PTR_ERR(state->regmap); + + indio_dev->info = &max5522_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = max5522_channels; + indio_dev->num_channels = ARRAY_SIZE(max5522_channels); + indio_dev->name = max5522_chip_info_tbl[ID_MAX5522].name; + + return devm_iio_device_register(&spi->dev, indio_dev); +} + +static const struct spi_device_id max5522_ids[] = { + { "max5522", (kernel_ulong_t)&max5522_chip_info_tbl[ID_MAX5522] }, + {} +}; +MODULE_DEVICE_TABLE(spi, max5522_ids); + +static const struct of_device_id max5522_of_match[] = { + { + .compatible = "maxim,max5522", + .data = &max5522_chip_info_tbl[ID_MAX5522], + }, + {} +}; +MODULE_DEVICE_TABLE(of, max5522_of_match); + +static struct spi_driver max5522_spi_driver = { + .driver = { + .name = "max5522", + .of_match_table = max5522_of_match, + }, + .probe = max5522_spi_probe, + .id_table = max5522_ids, +}; +module_spi_driver(max5522_spi_driver); + +MODULE_AUTHOR("Angelo Dureghello <angelo.dureghello@timesys.com"); +MODULE_DESCRIPTION("MAX5522 DAC driver"); +MODULE_LICENSE("GPL");
Add initial support for DAC max5522. Tested writing DAC A and B with some values, from 0 to 1023, measured output voltages, driver works properly. Additions for max5523/24/25 will follow. Signed-off-by: Angelo Dureghello <angelo.dureghello@timesys.com> --- Changes for v.2 - fix commit message - Kconfig, fix depends and select - Kconfig, fix typo - fix include alphabetical order - remove sysfs includes - fix MAX5522_REG_DATA macro - use devm_ as much as possible - add regulator_enable - remove useless code - remove commas after structure initializers and null terminators - change to use simplier module_spi_driver - get id->name from device info structure - regulator voltage read always from read_raw (no cache) Changes for v.3 - move signed-off to be before the changelog - re-fix include alphabetical order - remove vrefin_mv references - align function params with opening bracket - try to get chip_info from firmware - name always read from max5522_chip_info_tbl - remove line break before MODULE_DEVICE_TABLE --- drivers/iio/dac/Kconfig | 13 +++ drivers/iio/dac/Makefile | 1 + drivers/iio/dac/max5522.c | 207 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 221 insertions(+) create mode 100644 drivers/iio/dac/max5522.c