Re: loading firmware while usermodehelper disabled.

Jack Stone
2012-01-02T21:31:06Z

On 02/01/12 21:23, Linus Torvalds wrote:
> On Mon, Jan 2, 2012 at 1:09 PM, Jack Stone <jwjstone@fastmail.fm> wrote:
>>
>> What about USB "class" drivers e.g. usb-storage. They handle any device
>> that reports itself as a usb mass storage device. There could be a
>> device that needs to be bootstrapped before it becomes a generic usb
>> mass storage device. Do we really want to have to write a new driver
>> that is almost identical to the generic driver but handles the USB
>> firmware correctly.
>
> I'd hope that the generic driver just expose enough interfaces that
> you could basically do a "firmware-load" driver that just loads the
> firmware and then attaches the device to the generic driver.

Sounds workable.

To make the firmware caching easier I would propose one extra function
in addition to the aforemensioned get_firmware / put_firmware - a
find_firmware function to search the cache and return the appropriate
firmware blob. It should only be called if the caller already has a
refcount to the firmware, it's only use is to save every driver saving a
pointer to the firmware.

If noone beats me to it I will try and put together an RFC for a new
version.

Thanks,

Jack