On 6/29/22 15:19, Tomi Valkeinen wrote:
On 29/06/2022 15:39, Marek Vasut wrote:
On 6/29/22 14:26, Tomi Valkeinen wrote:
[...]
Perhaps the best way to solve this is just to remove the underscores
from __v4l2_subdev_state_alloc, and change all the drivers which
create
temporary v4l2_subdev_states to use that (and the free) functions. And
also create the helper macro which can be used in those cases where
the
call is simple (the state is not modified or accessed by the caller).
As long as we prevent any new driver from using that API, that's fine
with me.
An alternative would be to keep the v4l2_subdev_state as a local
variable (allocated in the stack), and add a new function,
v4l2_subdev_state_local_init() or such. The function would initialize
the given state, expecting the allocatable fields to be already
allocated (state->pads, which in the above cases points to another
local variable, i.e. stack).
This would prevent the need of a free call, which, while not complex
as such, might cause a bigger amount of changes in some cases to
handle the error paths correctly.
Of course, if the above-mentioned macro works, then that's the
easiest solution. But that won't work for all drivers.
Don't you think a driver fix shouldn't involve "rework the subsystem"
requirement to be applicable ?
No, but we should think what's the best way to do the fix, if the fix
is controversial. Otherwise we might just break things even worse.
Adding the macro seems like a much better way, and far from "rework the
subsystem". Granted, this was just a quick edit without testing so it may
fail miserably...
Can you try this out?
It seems to work as well. How shall we proceed ?
