Hi David, minor stuff from me... On Fri, 2023-12-08 at 09:51 -0600, David Lechner wrote: > This adds a new driver for the AD7380 family ADCs. > > The driver currently implements basic support for the AD7380, AD7381, > AD7383, and AD7384 2-channel differential ADCs. Support for additional > single-ended and 4-channel chips that use the same register map as well > as additional features of the chip will be added in future patches. > > Co-developed-by: Stefan Popa <stefan.popa@xxxxxxxxxx> > Signed-off-by: Stefan Popa <stefan.popa@xxxxxxxxxx> > Signed-off-by: David Lechner <dlechner@xxxxxxxxxxxx> > --- > MAINTAINERS | 1 + > drivers/iio/adc/Kconfig | 16 ++ > drivers/iio/adc/Makefile | 1 + > drivers/iio/adc/ad7380.c | 467 > +++++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 485 insertions(+) > > diff --git a/MAINTAINERS b/MAINTAINERS > index e2a998be5879..5a54620a31b8 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -438,6 +438,7 @@ S: Supported > W: > https://wiki.analog.com/resources/tools-software/linux-drivers/iio-adc/ad738x > W: https://ez.analog.com/linux-software-drivers > F: Documentation/devicetree/bindings/iio/adc/adi,ad7380.yaml > +F: drivers/iio/adc/ad7380.c > > AD7877 TOUCHSCREEN DRIVER > M: Michael Hennerich <michael.hennerich@xxxxxxxxxx> > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 35f9867da12c..cbfd626712e3 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -122,6 +122,22 @@ config AD7298 > To compile this driver as a module, choose M here: the > module will be called ad7298. > > +config AD7380 > + tristate "Analog Devices AD7380 ADC driver" > + depends on SPI_MASTER > + select IIO_BUFFER > + select IIO_TRIGGER > + select IIO_TRIGGERED_BUFFER > + help > + AD7380 is a family of simultaneous sampling ADCs that share the > same > + SPI register map and have similar pinouts. > + > + Say yes here to build support for Analog Devices AD7380 ADC and > + similar chips. > + > + To compile this driver as a module, choose M here: the module will > be > + called ad7380. > + > config AD7476 > tristate "Analog Devices AD7476 1-channel ADCs driver and other > similar devices from AD and TI" > depends on SPI > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index bee11d442af4..e046d8004f41 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -16,6 +16,7 @@ obj-$(CONFIG_AD7291) += ad7291.o > obj-$(CONFIG_AD7292) += ad7292.o > obj-$(CONFIG_AD7298) += ad7298.o > obj-$(CONFIG_AD7923) += ad7923.o > +obj-$(CONFIG_AD7476) += ad7380.o > obj-$(CONFIG_AD7476) += ad7476.o > obj-$(CONFIG_AD7606_IFACE_PARALLEL) += ad7606_par.o > obj-$(CONFIG_AD7606_IFACE_SPI) += ad7606_spi.o > diff --git a/drivers/iio/adc/ad7380.c b/drivers/iio/adc/ad7380.c > new file mode 100644 > index 000000000000..6a5ec59bd1fd > --- /dev/null > +++ b/drivers/iio/adc/ad7380.c > @@ -0,0 +1,467 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Analog Devices AD738x Simultaneous Sampling SAR ADCs > + * > + * Copyright 2017 Analog Devices Inc. > + * Copyright 2023 BayLibre, SAS > + */ > + > +#include <linux/bitfield.h> > +#include <linux/bitops.h> > +#include <linux/cleanup.h> > +#include <linux/device.h> > +#include <linux/err.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/regmap.h> > +#include <linux/regulator/consumer.h> > +#include <linux/slab.h> > +#include <linux/spi/spi.h> > +#include <linux/sysfs.h> > + > +#include <linux/iio/buffer.h> > +#include <linux/iio/iio.h> > +#include <linux/iio/sysfs.h> > +#include <linux/iio/trigger_consumer.h> > +#include <linux/iio/triggered_buffer.h> > + > ... > + > +static int ad7380_debugfs_reg_access(struct iio_dev *indio_dev, u32 reg, > + u32 writeval, u32 *readval) > +{ > + struct ad7380_state *st = iio_priv(indio_dev); > + int ret; > + > + ret = iio_device_claim_direct_mode(indio_dev); > + if (ret) > + return ret; > + potential controversial take: do we really need locking in here? regmap already has it's own lock (I think you're not disabling it) and if someone plays with registers it shouldn't while buffering, well... This is a debug interface so I would probably not worry much. One could anyways for write stuff by going directly to regmap :) That said, fine to be as-is from my side (just wanted to take it out of my system :))... > + if (readval) > + ret = regmap_read(st->regmap, reg, readval); > + else > + ret = regmap_write(st->regmap, reg, writeval); > + > + iio_device_release_direct_mode(indio_dev); > + > + return ret; > +} > + > +static irqreturn_t ad7380_trigger_handler(int irq, void *p) > +{ > + struct iio_poll_func *pf = p; > + struct iio_dev *indio_dev = pf->indio_dev; > + struct ad7380_state *st = iio_priv(indio_dev); > + struct spi_transfer xfer = { > + .bits_per_word = st->chip_info- > >channels[0].scan_type.realbits, > + .len = 4, > + .rx_buf = &st->scan_data, > + }; > + int ret; > + > + ret = spi_sync_transfer(st->spi, &xfer, 1); > + > + if (ret == 0) > + iio_push_to_buffers_with_timestamp(indio_dev, &st->scan_data, > + pf->timestamp); > + > + iio_trigger_notify_done(indio_dev->trig); > + > + return IRQ_HANDLED; > +} > + > +static int ad7380_read_direct(struct ad7380_state *st, > + struct iio_chan_spec const *chan, int *val) > +{ > + struct spi_transfer xfers[] = { > + /* toggle CS (no data xfer) to trigger a conversion */ > + { > + .speed_hz = AD7380_REG_WR_SPEED_HZ, > + .bits_per_word = chan->scan_type.realbits, > + .delay = { > + .value = 190, /* t[CONVERT] */ > + .unit = SPI_DELAY_UNIT_NSECS, > + }, > + .cs_change = 1, > + .cs_change_delay = { > + .value = 10, /* t[CSH] */ > + .unit = SPI_DELAY_UNIT_NSECS, > + }, > + }, > + /* then read both channels */ > + { > + .speed_hz = AD7380_REG_WR_SPEED_HZ, > + .bits_per_word = chan->scan_type.realbits, > + .rx_buf = &st->rx[0], > + .len = 4, > + }, > + }; > + int ret; > + > + ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers)); > + > + if (ret < 0) > + return ret; > + > + *val = sign_extend32(st->rx[chan->scan_index], > + chan->scan_type.realbits - 1); > + > + return IIO_VAL_INT; > +} > + > +static int ad7380_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, long info) > +{ > + struct ad7380_state *st = iio_priv(indio_dev); > + int ret; > + > + switch (info) { > + case IIO_CHAN_INFO_RAW: > + ret = iio_device_claim_direct_mode(indio_dev); > + if (ret) > + return ret; > + > + ret = ad7380_read_direct(st, chan, val); > + iio_device_release_direct_mode(indio_dev); > + > + return ret; > + case IIO_CHAN_INFO_SCALE: > + if (st->vref) { > + ret = regulator_get_voltage(st->vref); nit: I wonder how likely it is for vref to change at runtime... > + if (ret < 0) > + return ret; > + > + *val = ret / 1000; > + } else { > + *val = AD7380_INTERNAL_REF_MV; > + } > + > + *val2 = chan->scan_type.realbits; > + > + return IIO_VAL_FRACTIONAL_LOG2; > + } > + > + return -EINVAL; > +} > + > +static const struct iio_info ad7380_info = { > + .read_raw = &ad7380_read_raw, > + .debugfs_reg_access = &ad7380_debugfs_reg_access, > +}; > + > +static int ad7380_init(struct ad7380_state *st) > +{ > + int ret; > + > + /* perform hard reset */ > + ret = regmap_update_bits(st->regmap, AD7380_REG_ADDR_CONFIG2, > + AD7380_CONFIG2_RESET, > + FIELD_PREP(AD7380_CONFIG2_RESET, > + AD7380_CONFIG2_RESET_HARD)); > + if (ret < 0) > + return ret; > + > + > + /* select internal or external reference voltage */ > + ret = regmap_update_bits(st->regmap, AD7380_REG_ADDR_CONFIG1, > + AD7380_CONFIG1_REFSEL, > + FIELD_PREP(AD7380_CONFIG1_REFSEL, !!st- > >vref)); > + if (ret < 0) > + return ret; > + > + /* SPI 1-wire mode */ > + return regmap_update_bits(st->regmap, AD7380_REG_ADDR_CONFIG2, > + AD7380_CONFIG2_SDO, > + FIELD_PREP(AD7380_CONFIG2_SDO, 1)); > +} > + > +static void ad7380_release_regulator(void *p) > +{ > + struct regulator *reg = p; > + > + regulator_disable(reg); > +} > + > +static int ad7380_probe(struct spi_device *spi) > +{ > + struct iio_dev *indio_dev; > + struct ad7380_state *st; > + const char *str_val; > + int ret; > + > + ret = device_property_read_string(&spi->dev, "adi,sdo-mode", > &str_val); > + if (ret < 0) > + return dev_err_probe(&spi->dev, ret, > + "Failed to read adi,sdo-mode > property\n"); > + > + if (strcmp(str_val, "1-wire")) > + return dev_err_probe(&spi->dev, -EINVAL, > + "Only 1-wire SDO is supported\n"); > + > + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); > + if (!indio_dev) > + return -ENOMEM; > + > + st = iio_priv(indio_dev); > + st->spi = spi; > + st->chip_info = spi_get_device_match_data(spi); > + if (!st->chip_info) ? > + st->vref = devm_regulator_get_optional(&spi->dev, "refio"); > + if (IS_ERR(st->vref)) { > + /* > + * If there is no REFIO supply, then it means that we are > using > + * the internal 2.5V reference. > + */ > + if (PTR_ERR(st->vref) == -ENODEV) > + st->vref = NULL; > + else > + return dev_err_probe(&spi->dev, PTR_ERR(st->vref), > + "Failed to get refio > regulator\n"); > + } > + > + if (st->vref) { > + ret = regulator_enable(st->vref); > + if (ret) > + return ret; > + > + ret = devm_add_action_or_reset(&spi->dev, > ad7380_release_regulator, > + st->vref); > + if (ret) > + return ret; > + } > + > + st->regmap = devm_regmap_init(&spi->dev, NULL, st, > &ad7380_regmap_config); > + if (IS_ERR(st->regmap)) > + return dev_err_probe(&spi->dev, PTR_ERR(st->regmap), > + "failed to allocate register map\n"); > + Could we instead have a custom regmap_bus instead of bypass regmap with reg_read() and reg_write()? > + > + indio_dev->channels = st->chip_info->channels; > + indio_dev->num_channels = st->chip_info->num_channels; > + indio_dev->dev.parent = &spi->dev; no need to assign parent (the core does it for you)... - Nuno Sá
