Re: [RFC][PATCH -mm 3/3] PM: Disable _request_firmware before hibernation/suspend

Ray Lee
2007-05-28T20:51:15Z

On 5/28/07, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> On Monday, 28 May 2007 17:55, Alan Stern wrote:
> > You're using the PM_PRE_FREEZE and PM_POST_THAW notifiers for both this
> > and the userspace helper change. Is it your intention that drivers
> > should continue to request these services but encounter an error if the
> > request occurs at the wrong time? Or do you expect drivers to use the
> > notifier chains to know when they shouldn't make any requests?
>
> In fact, I'd like drivers to use notifiers to actually load the firmware into
> memory before hibernation/suspend. Namely, if there's PM_PRE_FREEZE, the
> driver calls request_firmware() from within the notifier and saves the firmware
> in memory for future use, if need be. Later, when PM_POST_THAW comes, the
> memory holding the firmware is released.
>
> Unfortunately there are drivers that call request_firmware() directly from
> .resume() which blocks until timeout expires and fails anyway. I just wanted
> this to fail immediately, without waiting.

Stupid question time. Wouldn't it just be easier to have
request_firmware() keep a copy of the firmware once it's been loaded?
We're not talking about a lot of memory that would be wasted, and that
way no drivers have to be changed.

Ray