remoteproc: simplify unregister/free interfaces
Simplify the unregister/free interfaces, and make them easier
to understand and use, by moving to a symmetric and consistent
alloc() -> register() -> unregister() -> free() flow.
To create and register an rproc instance, one needed to invoke
rproc_alloc() followed by rproc_register().
To unregister and free an rproc instance, one now needs to invoke
rproc_unregister() followed by rproc_free().
Cc: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
diff --git a/Documentation/remoteproc.txt b/Documentation/remoteproc.txt
index 70a048c..ad6ded4 100644
--- a/Documentation/remoteproc.txt
+++ b/Documentation/remoteproc.txt
@@ -120,14 +120,14 @@
On success, the new rproc is returned, and on failure, NULL.
Note: _never_ directly deallocate @rproc, even if it was not registered
- yet. Instead, if you just need to unroll rproc_alloc(), use rproc_free().
+ yet. Instead, when you need to unroll rproc_alloc(), use rproc_free().
void rproc_free(struct rproc *rproc)
- Free an rproc handle that was allocated by rproc_alloc.
- This function should _only_ be used if @rproc was only allocated,
- but not registered yet.
- If @rproc was already successfully registered (by calling
- rproc_register()), then use rproc_unregister() instead.
+ This function essentially unrolls rproc_alloc(), by decrementing the
+ rproc's refcount. It doesn't directly free rproc; that would happen
+ only if there are no other references to rproc and its refcount now
+ dropped to zero.
int rproc_register(struct rproc *rproc)
- Register @rproc with the remoteproc framework, after it has been
@@ -143,19 +143,14 @@
probed.
int rproc_unregister(struct rproc *rproc)
- - Unregister a remote processor, and decrement its refcount.
- If its refcount drops to zero, then @rproc will be freed. If not,
- it will be freed later once the last reference is dropped.
-
+ - Unroll rproc_register().
This function should be called when the platform specific rproc
implementation decides to remove the rproc device. it should
_only_ be called if a previous invocation of rproc_register()
has completed successfully.
- After rproc_unregister() returns, @rproc is _not_ valid anymore and
- it shouldn't be used. More specifically, don't call rproc_free()
- or try to directly free @rproc after rproc_unregister() returns;
- none of these are needed, and calling them is a bug.
+ After rproc_unregister() returns, @rproc is still valid, and its
+ last refcount should be decremented by calling rproc_free().
Returns 0 on success and -EINVAL if @rproc isn't valid.