Apparently, despite the name Digital Input Configuration Register, the
settings in the DIN_CONFIGx registers also affect other channel
functions. In particular, setting a non-zero value in the DIN_SINK
field breaks the resistance measurement function.
Now, one can of course argue that specifying a drive-strength-microamp
property along with a adi,ch-func which is not one of the digital
input functions is a bug in the device tree. However, we have a rather
complicated setup with instances of ad74412r on external hardware
modules, and have set a default drive-strength-microamp in our DT
fragments describing those, merely modifying the adi,ch-func settings
to reflect however the modules have been wired up. And restricting
this setting to just being done for digital input doesn't make the
driver any more complex.
Fixes: 504eb48558 (iio: ad74413r: wire up support for drive-strength-microamp property)
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20230503105042.453755-1-linux@rasmusvillemoes.dk
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
ADC sample captures take a certain amount of time to complete after
initiated; this conversion time range can be anywhere from 5
microseconds to 53.68 seconds depending on the configuration of the
Analog Input Frame Timer register. When the conversion is in progress,
the ADC Status register CNV bit is high. Call regmap_read_poll_timeout()
to poll until the ADC conversion is completed (or timeout if more than
53.68 seconds passes).
Suggested-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Link: https://lore.kernel.org/r/9ef433f107afd1d4dcd2d97ef0e932d7045c2bbd.1680790580.git.william.gray@linaro.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Currently, the driver handles CH_FUNC_CURRENT_INPUT_LOOP_POWER and
CH_FUNC_CURRENT_INPUT_EXT_POWER completely identically. But that's not
correct. In order for CH_FUNC_CURRENT_INPUT_LOOP_POWER to work, two
changes must be made:
(1) expose access to the DAC_CODE_x register so that the intended
output current can be set, i.e. expose the channel as both current
output and current input, and
(2) per the data sheet
When selecting the current input loop powered function, tie the
VIOUTN_x pin to ground via the on-chip 200 kΩ resistor by enabling
the CH_200K_TO_GND bit in the ADC_CONFIGx registers.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20230301115511.849418-1-linux@rasmusvillemoes.dk
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
We have a board where the reset pin of the ad74412 is connected to a
gpio, but also pulled low (i.e., asserted) by default. Hence to get
the chip out of reset, the driver needs to know about that gpio and
deassert the reset signal before attempting to communicate with the
chip.
When a reset-gpio is given in device tree, use that instead of the
software reset. According to the data sheet, the two methods are
functionally equivalent.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20221115095517.1008632-4-linux@rasmusvillemoes.dk
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The AD74115H is a single-channel, software-configurable, input and
output device for industrial control applications. The AD74115H
provides a wide range of use cases, integrated on a single chip.
These use cases include analog output, analog input, digital output,
digital input, resistance temperature detector (RTD), and thermocouple
measurement capability. The AD74115H also has an integrated HART modem.
A serial peripheral interface (SPI) is used to handle all communications
to the device, including communications with the HART modem. The digital
input and digital outputs can be accessed via the SPI or the
general-purpose input and output (GPIO) pins to support higher
speed data rates.
The device features a 16-bit, sigma-delta analog-to-digital converter
(ADC) and a 14-bit digital-to-analog converter (DAC).
The AD74115H contains a high accuracy 2.5 V on-chip reference that can
be used as the DAC and ADC reference.
Signed-off-by: Cosmin Tanislav <cosmin.tanislav@analog.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20221117080916.411766-3-cosmin.tanislav@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The constant AD74413R_ADC_RESULT_MAX is defined via GENMASK, so its
type is "unsigned long".
Hence in the expression voltage_offset * AD74413R_ADC_RESULT_MAX,
voltage_offset is first promoted to unsigned long, and since it may be
negative, that results in a garbage value. For example, when range is
AD74413R_ADC_RANGE_5V_BI_DIR, voltage_offset is -2500 and
voltage_range is 5000, so the RHS of this assignment is, depending on
sizeof(long), either 826225UL or 3689348814709142UL, which after
truncation to int then results in either 826225 or 1972216214 being
the output from in_currentX_offset.
Casting to int avoids that promotion and results in the correct -32767
output.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Fixes: fea251b6a5 (iio: addac: add AD74413R driver)
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20221118123209.1658420-1-linux@rasmusvillemoes.dk
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
I don't believe it's possible to hit this, because we drop
out of __iio_update_buffers() earlier in the event of an empty
list. However, that is not visible to the compiler so lets
return an error if we do hit the loop with an empty bitmask.
Fixes: 5d97d9e9a7 ("iio: addac: ad74413r: fix off by one in ad74413r_parse_channel_config()")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Cosmin Tanislav <cosmin.tanislav@analog.com>
Link: https://lore.kernel.org/r/20211220164726.3136307-1-jic23@kernel.org
The AD74412R and AD74413R are quad-channel, software configurable,
input/output solutions for building and process control applications.
They contain functionality for analog output, analog input, digital input,
resistance temperature detector, and thermocouple measurements integrated
into a single chip solution with an SPI interface.
The devices feature a 16-bit ADC and four configurable 13-bit DACs to
provide four configurable input/output channels and a suite of diagnostic
functions.
The AD74413R differentiates itself from the AD74412R by being
HART-compatible.
When configured with channel 0 as voltage output, channel 1 as current
output, channel 2 as voltage input and channel 3 as current input, the
following structure is created under the corresponding IIO device.
.
├── in_current0_offset
├── in_current0_raw
├── in_current0_sampling_frequency
├── in_current0_sampling_frequency_available
├── in_current0_scale
├── in_voltage1_offset
├── in_voltage1_raw
├── in_voltage1_sampling_frequency
├── in_voltage1_sampling_frequency_available
├── in_voltage1_scale
├── in_voltage2_offset
├── in_voltage2_raw
├── in_voltage2_sampling_frequency
├── in_voltage2_sampling_frequency_available
├── in_voltage2_scale
├── in_current3_offset
├── in_current3_raw
├── in_current3_sampling_frequency
├── in_current3_sampling_frequency_available
├── in_current3_scale
├── out_voltage0_raw
├── out_voltage0_scale
├── out_current1_raw
├── out_current1_scale
├── name
├── buffer
│ ├── data_available
│ ├── enable
│ ├── length
│ └── watermark
└── scan_elements
├── in_current0_en
├── in_current0_index
├── in_current0_type
├── in_voltage1_en
├── in_voltage1_index
├── in_voltage1_type
├── in_voltage2_en
├── in_voltage2_index
├── in_voltage2_type
├── in_current3_en
├── in_current3_index
└── in_current3_type
Signed-off-by: Cosmin Tanislav <cosmin.tanislav@analog.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20211205114045.173612-4-cosmin.tanislav@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
