The ROHM BD79105 is a simple 16-bit ADC accessible via SPI*.
The BD79105 has a CONVSTART pin, which must be set high to start the ADC
conversion. Unlike with the ad7091 and ad7091r which also have a
CONVSTART pin, the BD79105 requires that the pin must remain high also
for the duration of the SPI access.
(*) Couple of words about the SPI. The BD79105 has pins named as
CONVSTART, SCLK, DIN and DOUT. For the curious reader, DIN is not SPI
ISO.
DIN is a signal which can be used as a chip-select. When DIN is pulled
low, the ADC will output the completed measurement via DOUT as SCLK is
clocked. According to the data-sheet, the DIN can also be used for
daisy-chaining multiple ADCs. Furthermore, DOUT can be used also for a
'data-ready' -IRQ. These modes aren't supported by this driver.
Support reading ADC scale and data from the BD79105 using SPI, when DIN
is used as a chip-select.
Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://patch.msgid.link/6ee06d551256db9213ccbe72f44cfe9452717716.1754901948.git.mazziesaccount@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The ROHM BD79105 is a simple, 16-bit, 1-channel ADC with a 'CONVSTART'
pin used to start the ADC conversion. Other than the 'CONVSTART', there
are 3 supply pins (one used as a reference), analog inputs, ground and
communication pins. It's worth noting that the pin somewhat confusingly
labeled as 'DIN', is a pin which should be used as a chip-select. The IC
does not have any writable registers.
The device is designed so that the output pin can, in addition to
outputting the data, be used as a 'data-ready'-IRQ. There are cases
where the IRQ can't be used (because it is delivered via SPI data-line).
Hence, some systems may use a GPIO for polling the data readiness.
Add a compatible for the bd79105 and add the data-ready GPIO to the
binding.
Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/3f70f68665225be3091f8a0412e74037b6a2a88e.1754901948.git.mazziesaccount@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The ad7476 supports two IC variants which may have a 'convstart' -GPIO
for starting the conversion. Currently the driver calls a function which
tries to access the GPIO for all of the IC variants, whether they
support 'convstart' or not. This is not an error because this function
returns early if GPIO information is not populated.
We can do a tad better by calling this function only for the ICs which
have the 'convstart' by providing a function pointer to the convstart
function from the chip_info structure, and calling this function only
for the ICs which have the function pointer set.
This does also allow to support ICs which require different convstart
handling than the currently supported ICs.
Call convstart function only on the ICs which can support it and allow
IC-specific convstart functions for the ICs which require different
handling.
Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://patch.msgid.link/9760cde888fac7335c17d7ab63d5fb2e7c59ac51.1754901948.git.mazziesaccount@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The ad7476 driver defines separate chan_spec structures for operation
with and without convstart GPIO. At quick glance this may seem as if the
driver did provide more than 1 data-channel to users - one for the
regular data, other for the data obtained with the convstart GPIO.
The only difference between the 'convstart' and 'non convstart'
-channels is presence / absence of the BIT(IIO_CHAN_INFO_RAW) in
channel's flags.
We can drop the convstart channel spec, and related convstart macro, by
allocating a mutable per driver instance channel spec and adding the flag
in probe if needed. This will simplify the driver with the cost of added
memory consumption.
Assuming there aren't systems with very many ADCs and very few
resources, this tradeoff seems worth making.
Simplify the driver by dropping the 'convstart' channel spec and
allocating the channel spec for each driver instance.
Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://patch.msgid.link/cd7c72e3ee00f279d3381873f54e0c5b75b5ad11.1754901948.git.mazziesaccount@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The ad7476 driver supports ADCs which require a GPIO pin to be used to
start conversion. The GPIO line status seems to be always toggled from
a process context, either from the user-initiated "raw-read conversion",
or from a threaded IRQ handler. Furthermore, these ICs are connected via
SPI bus, which is usually implemented in a way that the access to the
device can sleep. The GPIO here is toggled from the same context which
is reading the results over SPI.
Thus it seems very likely these GPIOs are toggled from a context which
can sleep.
Swap the gpiod_set_value() to gpiod_set_value_cansleep() accordinlgy.
Suggested-by: Nuno Sá <noname.nuno@gmail.com>
Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://patch.msgid.link/a2d4b77e9739662797a1609f436b7f9807e1ac67.1754901948.git.mazziesaccount@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The ad7476 supports ADCs which use separate GPIO for starting the
conversion. For such devices, the driver uses different channel
information if the GPIO is found. The bit information is still always
used from the original (non 'convstart') channels.
This has not been causing problems because the bit information for the
'convstart' -channel and the 'normal' -channel is identical. It,
however, will cause issues if an IC has different characteristics for an
'convstart' -channel and regular channel. Furthermore, this will cause
problems if a device always requires the convstart GPIO and thus only
defines the convstart channel.
Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://patch.msgid.link/70619e39023bc497ef68cc1eff11943ab68cbdf8.1754901948.git.mazziesaccount@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The ad7476 driver supports variants with different amount of supply
regulators. On some variants there is only VCC, which is used as a
reference voltage. Others have separate VREF regulator, and some rely on
internal VREF. Some have both internal VREF and option to connect
external one.
The ad7476 driver reads the regulator voltage only when the user asks to
get the scale. This means the driver needs to do some dancing while
picking the correct reference regulator (or internal reference), and
store it for the later use.
According to the discussion [1] variable voltage references are rare,
making it hard to justify the added complexity for supporting those.
Drop the support for the variable voltage references and simplify things
by using the managed regulator get and enable interfaces.
Link: https://lore.kernel.org/linux-iio/20250331122247.05c6b09d@jic23-huawei/#1
Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: $URL #1
Link: https://patch.msgid.link/4a497cc5ac0f6506c1c94d10849e0ae1cacf1191.1754901948.git.mazziesaccount@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The ad7476 driver uses a table of structures for defining the IC variant
specific data. Table is indexed using enum values, which are picked by
SPI ID.
Having the table and an enum adds extra complexity and may encourage
adding IC specific quircks in the code, instead of centralizing the IC
differences in one place, the chip-info.
Simplify this by dropping the table and using individual structures for
the IC specific data, and storing the IC specific structure's address
directly in the SPI ID data. Finally, switch to the
spi_get_device_match_data() and add a check for the return value.
Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://patch.msgid.link/9e179bb3ba52303448ae4a559c1f011acd3f2fa6.1754901948.git.mazziesaccount@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Add Vishay VEML6046X00 high accuracy RGBIR color sensor.
This sensor provides three colour (red, green and blue) as well as one
infrared (IR) channel through I2C.
Support direct and buffered mode.
An optional interrupt for signaling green colour threshold underflow or
overflow is not supported so far.
Signed-off-by: Andreas Klinger <ak@it-klinger.de>
Link: https://patch.msgid.link/20250728075447.338725-3-ak@it-klinger.de
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
When `devm_add_action_or_reset()` fails, it is due to a failed memory
allocation and will thus return `-ENOMEM`. `dev_err_probe()` doesn't do
anything when error is `-ENOMEM`. Therefore, remove the useless call to
`dev_err_probe()` when `devm_add_action_or_reset()` fails, and just
return the value instead.
Signed-off-by: Waqar Hameed <waqar.hameed@axis.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://patch.msgid.link/pndectqm7te.a.out@axis.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Describe the inactivity detection additionally using the free-fall
register. Due to the controversial discussions on the mailing list, this
section of the documentation will be committed separately to allow for a
more focused and detailed elaboration of the topic.
Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
Link: https://patch.msgid.link/20250727210014.27766-8-l.rubusch@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Inactivity and free-fall events are essentially the same type of sensor
events. Therefore, inactivity detection (normally set for periods between 1
and 255 seconds) can be extended for shorter durations to support free-fall
detection.
For periods shorter than 1 second, the driver automatically configures the
threshold and duration using the free-fall register. For periods longer
than 1 second, it uses the inactivity threshold and duration using the
inactivity registers.
When using the free-fall register, the link bit is not set, which means
auto-sleep cannot be enabled if activity detection is also active.
Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
Link: https://patch.msgid.link/20250727210014.27766-6-l.rubusch@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Enable AC/DC coupling configuration for activity and inactivity detection
by setting the AC/DC bit. Extend existing magnitude-based detection with
adaptive AC-coupled mode.
Use DC-coupled mode to compare acceleration samples directly against
configured thresholds. Use AC-coupled mode to compare samples against a
reference taken at the start of activity detection. Implement DC-coupled
events using MAG, and AC-coupled events using MAG_ADAPTIVE.
Expose configuration of thresholds and periods via separate sysfs handles.
Note that both coupling modes share the same sensor registers, so activity
or inactivity detection cannot be configured for both AC and DC
simultaneously. Apply the most recently configured mode.
Simplify event handling and support adaptive AC-coupling.
Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
Link: https://patch.msgid.link/20250727210014.27766-5-l.rubusch@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Add support for the sensor’s inactivity feature in the driver. When both
activity and inactivity detection are enabled, the sensor sets a link bit
that ties the two functions together. This also enables auto-sleep mode,
allowing the sensor to automatically enter sleep state upon detecting
inactivity.
Inactivity detection relies on a configurable threshold and a specified
time period. If sensor measurements remain below the threshold for the
defined duration, the sensor transitions to the inactivity state.
When an Output Data Rate (ODR) is set, the inactivity time period is
automatically adjusted to a sensible default. Higher ODRs result in shorter
inactivity timeouts, while lower ODRs allow longer durations-within
reasonable upper and lower bounds. This is important because features like
auto-sleep operate effectively only between 12.5 Hz and 400 Hz. These
defaults are applied when the sample rate is modified, but users can
override them by explicitly setting a custom inactivity timeout.
Similarly, configuring the g-range provides default threshold values for
both activity and inactivity detection. These are implicit defaults meant
to simplify configuration, but they can also be manually overridden as
needed.
Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
Link: https://patch.msgid.link/20250727210014.27766-4-l.rubusch@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Enable the sensor to detect activity and trigger interrupts accordingly.
Activity events are determined based on a threshold, which is initialized
to a sensible default during probe. This default value is adopted from the
legacy ADXL345 input driver to maintain consistent behavior.
The combination of activity detection, ODR configuration, and range
settings lays the groundwork for the activity/inactivity hysteresis
mechanism, which will be implemented in a subsequent patch. As such,
portions of this patch prepare switch-case structures to support those
upcoming changes.
Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
Link: https://patch.msgid.link/20250727210014.27766-3-l.rubusch@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Driver is getting clock and almost immediately enabling it, with the
devm_request_irq() as the only relevant code executed between, thus the
probe path and cleanups can be simplified with devm_clk_get_enabled().
Move devm_request_irq() earlier, so the interrupt handler will be
registered before clock is enabled. This might be important in case
regulator supplies are enabled by other device driver and this device
raises interrupt immediately after clock sarts ticking.
The change does not reverse cleanup paths - first regulator will be
disabled, then clock and finally interrupt handler freed.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20250713-iio-clk-get-enabled-v1-1-70abc1f9ce6c@linaro.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Xichao Zhao
Akshay Jindal
Andrew Davis
Wolfram Sang
Matti Vaittinen
Erick Setubal Bacurau
Andreas Klinger
Waqar Hameed
Stefano Manni
Nuno Sá
Marcelo Schmitt
Lothar Rubusch
Rodrigo Gobbi
David Lechner
Krzysztof Kozlowski
Colin Ian King