IIO triggers are software IRQ chips that split an incoming IRQ into
separate IRQs routed to all devices using the trigger.
When all consumers are done then a trigger callback reenable() is
called. There are a few circumstances under which this can happen
in atomic context.
1) A single user of the trigger that calls the iio_trigger_done()
function from interrupt context.
2) A race between disconnecting the last device from a trigger and
the trigger itself sucessfully being disabled.
To avoid a resulting scheduling whilst atomic, close this second corner
by using schedule_work() to ensure the reenable is not done in atomic
context.
Note that drivers must be careful to manage the interaction of
set_state() and reenable() callbacks to ensure appropriate reference
counting if they are relying on the same hardware controls.
Deliberately taking this the slow path rather than via a fixes tree
because the error has hard to hit and I would like it to soak for a while
before hitting a release kernel.
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de>
Cc: <Stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20211017172209.112387-1-jic23@kernel.org
The shared parameter should be configurable based on its usage, and not
constrained to IIO_SHARED_BY_TYPE.
This patch aims to improve the flexibility in using the
IIO_ENUM_AVAILABLE define and avoid redefining custom iio enums that
expose the shared parameter.
An example is the ad5766.c driver where IIO_ENUM_AVAILABLE_SHARED was
defined in order to achieve `shared` parameter customization.
The current state of the IIO_ENUM_AVAILABLE implementation will imply
similar redefinitions each time a driver will require access to the
`shared` parameter. An example would be admv1013 driver which will
require custom device attribute for the frequency translation modes:
Quadrature I/Q mode and Intermediate Frequency mode.
Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
Reviewed-by: Alexandru Ardelean <ardeleanalex@gmail.com>
Link: https://lore.kernel.org/r/20211119085627.6348-1-antoniu.miclaus@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Now that output (kfifo) buffers are supported, we need to extend the
{devm_}iio_triggered_buffer_setup_ext() parameter list to take a direction
parameter.
This allows us to attach an output triggered buffer to a DAC device.
Unfortunately it's a bit difficult to add another macro to avoid changing 5
drivers where {devm_}iio_triggered_buffer_setup_ext() is used.
Well, it's doable, but may not be worth the trouble vs just updating all
these 5 drivers.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Mihail Chindris <mihail.chindris@analog.com>
Link: https://lore.kernel.org/r/20211007080035.2531-4-mihail.chindris@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Currently IIO only supports buffer mode for capture devices like ADCs. Add
support for buffered mode for output devices like DACs.
The output buffer implementation is analogous to the input buffer
implementation. Instead of using read() to get data from the buffer write()
is used to copy data into the buffer.
poll() with POLLOUT will wakeup if there is space available.
Drivers can remove data from a buffer using iio_pop_from_buffer(), the
function can e.g. called from a trigger handler to write the data to
hardware.
A buffer can only be either a output buffer or an input, but not both. So,
for a device that has an ADC and DAC path, this will mean 2 IIO buffers
(one for each direction).
The direction of the buffer is decided by the new direction field of the
iio_buffer struct and should be set after allocating and before registering
it.
Co-developed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Co-developed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Mihail Chindris <mihail.chindris@analog.com>
Link: https://lore.kernel.org/r/20211007080035.2531-2-mihail.chindris@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Whilst it is almost always possible to arrange for scan data to be
read directly into a buffer that is suitable for passing to
iio_push_to_buffers_with_timestamp(), there are a few places where
leading data needs to be skipped over.
For these cases introduce a function that will allocate an appropriate
sized and aligned bounce buffer (if not already allocated) and copy
the unaligned data into that before calling
iio_push_to_buffers_with_timestamp() on the bounce buffer.
We tie the lifespace of this buffer to that of the iio_dev.dev
which should ensure no memory leaks occur.
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20210613151039.569883-2-jic23@kernel.org
Some devices can't mask/unmask the data ready pin and in those cases
each driver was just calling '{dis}enable_irq()' to control the trigger
state. This change, moves that handling into the library by introducing
a new boolean in the data structure that tells the library that the
device cannot unmask the pin.
On top of controlling the trigger state, we can also use this flag to
automatically request the IRQ with 'IRQF_NO_AUTOEN' in case it is set.
So far, all users of the library want to start operation with IRQs/DRDY
pin disabled so it should be fairly safe to do this inside the library.
Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20210903141423.517028-3-nuno.sa@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This change introduces a device-managed variant to the
iio_map_array_register() function. It's a simple implementation of calling
iio_map_array_register() and registering a callback to
iio_map_array_unregister() with the devm_add_action_or_reset().
The function uses an explicit 'dev' parameter to bind the unwinding to. It
could have been implemented to implicitly use the parent of the IIO device,
however it shouldn't be too expensive to callers to just specify to which
device object to bind this unwind call.
It would make the API a bit more flexible.
Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Link: https://lore.kernel.org/r/20210903072917.45769-2-aardelean@deviqon.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The idea behind it, is that all devm_ calls in ST sensors are bound to the
parent device object.
However, the reference to that object is kept on both the st_sensor_data
struct and the IIO object parent (indio_dev->dev.parent).
This change only adds a bit consistency and uses the reference stored on
indio_dev->dev.parent, to enforce the assumption that all ST sensors' devm_
calls are bound to the same reference as the one store on st_sensor_data.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210823112204.243255-6-aardelean@deviqon.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This change converts the st_sensors_power_enable() function to use
devm_add_action_or_reset() handlers to register regulator_disable hooks for
when the drivers get unloaded.
The parent device of the IIO device object is used. This is based on the
assumption that all other devm_ calls in the ST sensors use this reference.
This makes the st_sensors_power_disable() un-needed.
Removing this also changes unload order a bit, as all ST drivers would call
st_sensors_power_disable() first and iio_device_unregister() after that.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210823112204.243255-4-aardelean@deviqon.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Since all AD Sigma-Delta drivers now use the
devm_ad_sd_setup_buffer_and_trigger() function, we can remove the old
ad_sd_{setup,cleanup}_buffer_and_trigger() functions.
This way we can discourage new drivers that use the ad_sigma_delta
lib-driver to use these (older functions).
Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Link: https://lore.kernel.org/r/20210513120752.90074-13-aardelean@deviqon.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This is a version of ad_sd_setup_buffer_and_trigger() with all underlying
functions (that are used) being replaced with their device-managed
variants.
One thing to take care here is with {devm_}iio_trigger_alloc(), where both
functions take a parent-device object as the first parameter.
To make sure nothing quirky is happening, the devm_ad_sd_probe_trigger()
function is checking that the provided 'dev' reference is the same as the
one stored on the 'struct ad_sigma_delta' driver data.
Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Link: https://lore.kernel.org/r/20210513120752.90074-6-aardelean@deviqon.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The samples buffer is passed to iio_push_to_buffers_with_timestamp()
which requires a buffer aligned to 8 bytes as it is assumed that
the timestamp will be naturally aligned if present.
Fixes tag is inaccurate but prior to that likely manual backporting needed
(for anything before 4.18) Earlier than that the include file to fix is
drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.h:
commit 974e6f02e2 ("iio: cros_ec_sensors_core: Add common functions
for the ChromeOS EC Sensor Hub.") present since kernel stable 4.10.
(Thanks to Gwendal for tracking this down)
Fixes: 5a0b8cb466 ("iio: cros_ec: Move cros_ec_sensors_core.h in /include")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org
Link: https://lore.kernel.org/r/20210501171352.512953-7-jic23@kernel.org
