Checking the binary representation of two structs (of the same type)
for equality doesn't have the same semantic as comparing all members for
equality. The former might find a difference where the latter doesn't in
the presence of padding or when ambiguous types like float or bool are
involved. (Floats typically have different representations for single
values, like -0.0 vs +0.0, or 0.5 * 2² vs 0.25 * 2³. The type bool has
at least 8 bits and the raw values 1 and 2 (probably) both evaluate to
true, but memcmp finds a difference.)
When searching for a channel that already has the configuration we need,
the comparison by member is the one that is needed.
Convert the comparison accordingly to compare the members one after
another. Also add a static_assert guard to (somewhat) ensure that when
struct ad7173_channel_config::config_props is expanded, the comparison
is adapted, too.
This issue is somewhat theoretic, but using memcmp() on a struct is a
bad pattern that is worth fixing.
Fixes: 76a1e6a428 ("iio: adc: ad7173: add AD7173 driver")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://patch.msgid.link/20250303114659.1672695-14-u.kleine-koenig@baylibre.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Checking the binary representation of two structs (of the same type)
for equality doesn't have the same semantic as comparing all members for
equality. The former might find a difference where the latter doesn't in
the presence of padding or when ambiguous types like float or bool are
involved. (Floats typically have different representations for single
values, like -0.0 vs +0.0, or 0.5 * 2² vs 0.25 * 2³. The type bool has
at least 8 bits and the raw values 1 and 2 (probably) both evaluate to
true, but memcmp finds a difference.)
When searching for a channel that already has the configuration we need,
the comparison by member is the one that is needed.
Convert the comparison accordingly to compare the members one after
another. Also add a static_assert guard to (somewhat) ensure that when
struct ad7124_channel_config::config_props is expanded, the comparison
is adapted, too.
This issue is somewhat theoretic, but using memcmp() on a struct is a
bad pattern that is worth fixing.
Fixes: 7b8d045e49 ("iio: adc: ad7124: allow more than 8 channels")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://patch.msgid.link/20250303114659.1672695-13-u.kleine-koenig@baylibre.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Checking the binary representation of two structs (of the same type)
for equality doesn't have the same semantic as comparing all members for
equality. The former might find a difference where the latter doesn't in
the presence of padding or when ambiguous types like float or bool are
involved. (Floats typically have different representations for single
values, like -0.0 vs +0.0, or 0.5 * 2² vs 0.25 * 2³. The type bool has
at least 8 bits and the raw values 1 and 2 (probably) both evaluate to
true, but memcmp finds a difference.)
When searching for a channel that already has the configuration we need,
the comparison by member is the one that is needed.
Convert the comparison accordingly to compare the members one after
another. Also add a static_assert guard to (somewhat) ensure that when
struct ad4130_setup_info is expanded, the comparison is adapted, too.
This issue is somewhat theoretic, but using memcmp() on a struct is a
bad pattern that is worth fixing.
Fixes: 62094060cf ("iio: adc: ad4130: add AD4130 driver")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://patch.msgid.link/20250303114659.1672695-12-u.kleine-koenig@baylibre.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The function ad_sd_calibrate() enables the channel to calibrate at
function entry but doesn't disable it on exit. This is problematic
because if two (or more) channels are calibrated in a row, the second
calibration isn't executed as intended as the first (still enabled)
channel is recalibrated and after the first irq (i.e. when the
calibration of the first channel completed) the calibration is aborted.
This currently affects ad7173 only, as the other drivers using
ad_sd_calibrate() never have more than one channel enabled at a time.
To fix this, disable the calibrated channel after calibration.
Fixes: 031bdc8aee ("iio: adc: ad7173: add calibration support")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://patch.msgid.link/20250303114659.1672695-11-u.kleine-koenig@baylibre.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Whilst an interesting part, no one has done significant work on this
driver since 2019. The recent changes are all as a result of adis library
improvements having to incorporate this device.
https://www.analog.com/en/products/adis16240.html now lists this part
as obsolete so the chances of anyone working on it are likely to be greatly
reduced.
So drop it. We can always bring it back if anyone does have interest in
this device and is willing to invest the time to make it suitable for a
staging graduation. How to handle the hardware triggered short bursts
of capture has never been resolved and is a somewhat challenging ABI design
problem.
Cc: Nuno Sa <nuno.sa@analog.com>
Cc: Rodrigo Carvalho <rodrigorsdc@gmail.com>
Link: https://patch.msgid.link/20250222152021.1039675-1-jic23@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The Successive Approximation ADC (SARADC) in RK3528 uses the v2
controller and support:
- 10-bit resolution
- Up to 1MS/s sampling rate
- 4 single-ended input channels
- Current consumption: 0.5mA @ 1MS/s
Add support for the 4 channels of 10-bit resolution supported by SARADC
in RK3528.
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patch.msgid.link/20250227184058.2964204-3-jonas@kwiboo.se
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The Successive Approximation ADC (SARADC) in RK3528 uses the v2
controller and support:
- 10-bit resolution
- Up to 1MS/s sampling rate
- 4 single-ended input channels
- Current consumption: 0.5mA @ 1MS/s
Add a rockchip,rk3562-saradc compatible string for the 4 channels of
10-bit resolution supported by SARADC in RK3528.
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patch.msgid.link/20250227184058.2964204-2-jonas@kwiboo.se
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reorganize the IRQ handler. Move the overrun handling to the bottom.
Overrun leads to reset the interrupt register. This also happens at
evaluation of a particular interrupt event. First evaluate an event
if possible, then fall back to overrun handling. Additionally simplify
fetching the interrupt status function.
Both is in preparation to build interrupt handling up for the handling
of different detected events, implemented in follow up patches.
Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
Link: https://patch.msgid.link/20250220104234.40958-4-l.rubusch@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
ADC inputs can be classified into a few different types according to how
they measure the input signal, how restrained the signal is, and number of
input pins. Even though datasheets tend to provide many details about their
inputs and measurement procedures, it may not always be clear how to model
those inputs into IIO channels.
For example, some differential ADCs can have their inputs configured into
pseudo-differential channels. In that configuration, only one input
connects to the signal of interest as opposed to using two inputs of a
differential input configuration. Datasheets sometimes also refer to
pseudo-differential inputs as single-ended inputs even though they have
distinct physical configuration and measurement procedure.
Document consolidated ADC input types and how they are usually described
and supported in device tree and IIO, respectively.
Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
Reviewed-by: David Lechner <dlechner@baylibre.com>
Link: https://patch.msgid.link/e6ac2a595f06ba2d5ff0eb86e5895479c9dd797f.1739998491.git.marcelo.schmitt@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Fix some out of bounds array access of st->channels_cfg in the ad4695
driver. This array only has elements for voltage channels, but it was
also being accessed for the temperature channel in a few cases causing
reading past the end of the array.
In some cases, this was harmless because the value was read but not
used. However, the in_temp_sampling_frequency attribute shares code
with the in_voltageY_sampling_frequency attributes and was trying to
read the oversampling ratio from the st->channels_cfg array. This
resulted in a garbage value being used in the calculation and the
resulting in_temp_sampling_frequency value was incorrect.
To fix, make sure we always check that we are dealing with a voltage
channel before accessing the st->channels_cfg array and use an
oversampling ratio of 1 for the temperature channel (multiplicative
identity value) since that channel doesn't support oversampling.
Fixes: 67d63185db ("iio: adc: ad4695: add offload-based oversampling support")
Signed-off-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Trevor Gamblin <tgamblin@baylibre.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://patch.msgid.link/20250218-iio-adc-ad4695-fix-out-of-bounds-array-access-v1-1-57fef8c7a3fd@baylibre.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
