linux.git/include/linux/iio, branch v6.14

iio: gts-helper: add helpers to ease searches of gain_sel and new_gain

2025-01-04T12:33:57+00:00

This helper functions reduce the burden in the drivers that want to
fetch a gain and time selector for a given scale or a new optimal gain.

The former is currently achieved by calling
iio_gts_find_gain_sel_for_scale_using_time() for the current time
selector, and then iterating over the rest of time selectors if the
gain selector was not found.

The latter requires a combination of multiple iio-gts helpers to find
the new gain, look for an optimal gain if there was no exact match, and
set a minimum gain if the optimal gain is not in the range of available
gains.

Provide simpler workflows by means of functions that address common
patterns in the users of the iio-gts helpers.

Acked-by: Matti Vaittinen 
Signed-off-by: Javier Carrasco 
Link: https://patch.msgid.link/20241230-veml3235_scale-v3-1-48a5795e2f64@gmail.com
Signed-off-by: Jonathan Cameron

iio: trigger: stm32-timer: add support for stm32mp25

2024-12-28T14:28:14+00:00

Add support for STM32MP25 SoC. Use newly introduced compatible to handle
this new HW variant. Add TIM20 trigger definitions that can be used by
the stm32 analog-to-digital converter. Use compatible data to identify
it.
As the counter framework is now superseding the deprecated IIO counter
interface (IIO_COUNT), don't support it. Only register IIO trigger
devices for ADC usage. So, make the valids_table a cfg option.

Signed-off-by: Fabrice Gasnier 
Link: https://patch.msgid.link/20241220095927.1122782-4-fabrice.gasnier@foss.st.com
Signed-off-by: Jonathan Cameron

iio: core: mark scan_timestamp as __private

2024-12-28T14:28:14+00:00

Since there are no more direct accesses to the indio_dev->scan_timestamp
value, it can be marked as __private and use the macro ACCESS_PRIVATE()
in order to access it. Like this, static checkers will be able to inform
in case someone tries to either write to the value, or read its value
directly.

Signed-off-by: Vasileios Amoiridis 
Link: https://patch.msgid.link/20241214191421.94172-5-vassilisamir@gmail.com
Signed-off-by: Jonathan Cameron

iio: consumers: ensure read buffers for labels and ext_info are page aligned

2024-12-11T19:20:49+00:00

Attributes of iio providers are exposed via sysfs. Typically, providers
pass attribute values to the iio core, which handles formatting and
printing to sysfs. However, some attributes, such as labels or extended
info, are directly formatted and printed to sysfs by provider drivers
using sysfs_emit() and sysfs_emit_at(). These helpers assume the read
buffer, allocated by sysfs fop, is page-aligned. When these attributes
are accessed by consumer drivers, the read buffer is allocated by the
consumer and may not be page-aligned, leading to failures in the
provider's callback that utilizes sysfs_emit*.

Add a check to ensure that read buffers for labels and external info
attributes are page-aligned. Update the prototype documentation as well.

Signed-off-by: Matteo Martelli 
Link: https://patch.msgid.link/20241202-iio-kmalloc-align-v1-1-aa9568c03937@gmail.com
Signed-off-by: Jonathan Cameron

iio: adc: ad_sigma_delta: Store information about reset sequence length

2024-12-11T19:20:48+00:00

The various chips can be reset using a sequence of SPI transfers with
MOSI = 1. The length of such a sequence varies from chip to chip. Store
that length in struct ad_sigma_delta_info and replace the respective
parameter to ad_sd_reset() with it.

Note the ad7192 used to pass 48 as length but the documentation
specifies 40 as the required length. Assuming the latter is right.
(Using a too long sequence doesn't hurt apart from using a longer spi
transfer than necessary, so this is no relevant fix.)

The motivation for storing this information is that this is useful to
clear a pending R̅D̅Y̅ signal in the next change.

Signed-off-by: Uwe Kleine-König 
Link: https://patch.msgid.link/9750db62fce638bf140ff48172c23bff7f785e5b.1733504533.git.u.kleine-koenig@baylibre.com
Signed-off-by: Jonathan Cameron

iio: adc: ad_sigma_delta: Fix a race condition

2024-12-11T19:20:48+00:00

The ad_sigma_delta driver helper uses irq_disable_nosync(). With that
one it is possible that the irq handler still runs after the
irq_disable_nosync() function call returns. Also to properly synchronize
irq disabling in the different threads proper locking is needed and
because it's unclear if the irq handler's irq_disable_nosync() call
comes first or the one in the enabler's error path, all code locations
that disable the irq must check for .irq_dis first to ensure there is
exactly one disable call per enable call.

So add a spinlock to the struct ad_sigma_delta and use it to synchronize
irq enabling and disabling. Also only act in the irq handler if the irq
is still enabled.

Fixes: af3008485ea0 ("iio:adc: Add common code for ADI Sigma Delta devices")
Signed-off-by: Uwe Kleine-König 
Link: https://patch.msgid.link/9e6def47e2e773e0e15b7a2c29d22629b53d91b1.1733504533.git.u.kleine-koenig@baylibre.com
Signed-off-by: Jonathan Cameron

iio: adc: ad_sigma_delta: Add support for reading irq status using a GPIO

2024-12-11T19:20:48+00:00

Some of the ADCs by Analog signal their irq condition on the MISO line.
So typically that line is connected to an SPI controller and a GPIO. The
GPIO is used as input and the respective interrupt is enabled when the
last SPI transfer is completed.

Depending on the GPIO controller the toggling MISO line might make the
interrupt pending even while it's masked. In that case the irq handler
is called immediately after irq_enable() and so before the device
actually pulls that line low which results in non-sense values being
reported to the upper layers.

The only way to find out if the line was actually pulled low is to read
the GPIO. (There is a flag in AD7124's status register that also signals
if an interrupt was asserted, but reading that register toggles the MISO
line and so might trigger another spurious interrupt.)

Add the possibility to specify an interrupt GPIO in the machine
description in addition to the plain interrupt. This GPIO is used then
to check if the irq line is actually active in the irq handler.

Signed-off-by: Uwe Kleine-König 
Link: https://patch.msgid.link/5be9a4cc4dc600ec384c88db01dd661a21506b9c.1733504533.git.u.kleine-koenig@baylibre.com
Signed-off-by: Jonathan Cameron

iio: core: fix doc reference to iio_push_to_buffers_with_ts_unaligned

2024-12-07T17:52:44+00:00

Use the right name of the function, which is defined in
drivers/iio/industrialio-buffer.c

Signed-off-by: Javier Carrasco 
Link: https://patch.msgid.link/20241125-iio_memset_scan_holes-v1-11-0cb6e98d895c@gmail.com
Signed-off-by: Jonathan Cameron

iio: imu: adis: Remove documented not used elements

2024-12-07T17:49:11+00:00

This patch removes elements from adis.h that are documented
but not used anymore.

Signed-off-by: Robert Budai 
Link: https://patch.msgid.link/20241125133520.24328-2-robert.budai@analog.com
Signed-off-by: Jonathan Cameron

iio: adc: ad_sigma_delta: add tab to align irq_line

2024-12-07T17:47:58+00:00

Align the irq_line field in struct ad_sigma_delta with the other fields.

Signed-off-by: David Lechner 
Link: https://patch.msgid.link/20241122-iio-adc-ad_signal_delta-fix-align-v1-1-d0a071d2dc83@baylibre.com
Signed-off-by: Jonathan Cameron