When using more than one trigger consumer it can happen that multiple threads
perform a read-modify-update cycle on 'use_count' concurrently. This can cause
updates to be lost and use_count can get stuck at non-zero value, in which case
the IIO core assumes that at least one thread is still running and will wait for
it to finish before running any trigger handlers again. This effectively renders
the trigger disabled and a reboot is necessary before it can be used again. To
fix this make use_count an atomic variable. Also set it to the number of
consumers before starting the first consumer, otherwise it might happen that
use_count drops to 0 even though not all consumers have been run yet.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Tested-by: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Use dev_{set,get}_drvdata for managing private data attached to a trigger
instead of using a custom field in the iio_trigger struct.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Introduce iio_tigger_{set,get}_drvdata which allows to attach driver specific
data to a trigger. The functions wrap access to the triggers private_data field
and all current users are updated to use iio_tigger_{set,get}_drvdata instead of
directly accessing the private_data field. This is the first step towards
removing the private_data field from the iio_trigger struct.
The following coccinelle script has been used to update the drivers:
<smpl>
@@
struct iio_trigger *trigger;
expression priv;
@@
-trigger->private_data = priv
+iio_trigger_set_drv_data(trigger, priv)
@@
struct iio_trigger *trigger;
@@
-trigger->private_data
+iio_trigger_get_drv_data(trigger)
</smpl>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Also include a couple of forward defs of struct iio_trigger and struct
iio_trigger_ops to avoid doing this in each driver.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Denis Ciocca <denis.ciocca@st.com>
Currently we use two different naming schemes in the IIO API, iio_verb_object
and iio_object_verb. E.g iio_device_register and iio_allocate_device. This
patches renames instances of the later to the former. The patch also renames allocate to
alloc as this seems to be the preferred form throughout the kernel.
In particular the following renames are performed by the patch:
iio_put_device -> iio_device_put
iio_allocate_device -> iio_device_alloc
iio_free_device -> iio_device_free
iio_get_trigger -> iio_trigger_get
iio_put_trigger -> iio_trigger_put
iio_allocate_trigger -> iio_trigger_alloc
iio_free_trigger -> iio_trigger_free
The conversion was done with the following coccinelle patch with manual fixes to
comments and documentation.
<smpl>
@@
@@
-iio_put_device
+iio_device_put
@@
@@
-iio_allocate_device
+iio_device_alloc
@@
@@
-iio_free_device
+iio_device_free
@@
@@
-iio_get_trigger
+iio_trigger_get
@@
@@
-iio_put_trigger
+iio_trigger_put
@@
@@
-iio_allocate_trigger
+iio_trigger_alloc
@@
@@
-iio_free_trigger
+iio_trigger_free
</smpl>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Step 1 in moving the IIO core out of staging.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-25 11:01:43 -07:00
Renamed from drivers/staging/iio/trigger.h (Browse further)