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b09c61522c
This reverts commit 43fff76834 ("Bluetooth: hci_bcm: Streamline runtime
PM code"). The commit msg for this commit states "No functional change
intended.", but replacing:
pm_runtime_get();
pm_runtime_mark_last_busy();
pm_runtime_put_autosuspend();
with:
pm_request_resume();
Does result in a functional change, pm_request_resume() only calls
pm_runtime_mark_last_busy() if the device was suspended before the call.
This results in the following happening:
1) Device is runtime suspended
2) Device drives host_wake IRQ logically high as it starts receiving data
3) bcm_host_wake() gets called, causes the device to runtime-resume,
current time gets marked as last_busy time
4) After 5 seconds the autosuspend timer expires and the dev autosuspends
as no one has been calling pm_runtime_mark_last_busy(), the device was
resumed during those 5 seconds, so all the pm_request_resume() calls
while receiving data and/or bcm_host_wake() calls were nops
5) If 4) happens while the device has (just received) data in its buffer to
be read by the host the IRQ line is *already* / still logically high
when we autosuspend and since we use an edge triggered IRQ, the IRQ
will never trigger, causing the device to get stuck in suspend
Therefor this commit has to be reverted, so that we avoid the device
getting stuck in suspend.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.