From 6a927857d890658789e6e54b058ef8527de8200a Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Sat, 3 Nov 2012 17:48:16 +0800 Subject: [PATCH] firmware loader: document firmware cache mechanism This patch documents the firmware cache mechanism so that users of request_firmware() know that it can be called safely inside device's suspend and resume callback, and the device's firmware needn't be cached any more by individual driver itself to deal with firmware loss during system resume. Signed-off-by: Ming Lei Signed-off-by: Greg Kroah-Hartman --- Documentation/firmware_class/README | 7 +++++++ drivers/base/firmware_class.c | 3 +++ 2 files changed, 10 insertions(+) diff --git a/Documentation/firmware_class/README b/Documentation/firmware_class/README index e9fce78c413..43fada989e6 100644 --- a/Documentation/firmware_class/README +++ b/Documentation/firmware_class/README @@ -119,3 +119,10 @@ on the setup, so I think that the choice on what firmware to make persistent should be left to userspace. + about firmware cache: + -------------------- + After firmware cache mechanism is introduced during system sleep, + request_firmware can be called safely inside device's suspend and + resume callback, and callers need't cache the firmware by + themselves any more for dealing with firmware loss during system + resume. diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c index 7888af7941a..d8146030918 100644 --- a/drivers/base/firmware_class.c +++ b/drivers/base/firmware_class.c @@ -988,6 +988,9 @@ err_put_dev: * firmware image for this or any other device. * * Caller must hold the reference count of @device. + * + * The function can be called safely inside device's suspend and + * resume callback. **/ int request_firmware(const struct firmware **firmware_p, const char *name,