Messages in this thread | | | Date | Mon, 23 Apr 2012 16:18:56 -0400 | Subject | what determines how firmware is loaded? (Q. on request_firmware details) | From | George Nychis <> |
| |
Hi all,
I notice in an older version of Ubuntu that when I plugin a USB wireless device its firmware is loaded via sysfs. For example, this would pop up in sysfs: /sys/devices/pci0000:00/0000:00:1d.7/usb2/2-1/compat_firmware/2-1/loading
In newer versions, I'm now seeing that the firmware seems to be loaded directly via a Kernel thread that is spawned. It checks for the firmware in some firmware directory (e.g., /lib/firmware) and loads it to the device.
I see in documentation that one method is referred to as asynchronous. Is this the former or latter?
Has the former method of loading firmware been removed as the default? Is there any way to request that the firmware load be done manually (the former method)?
It seems as though instead of calling request_firmware(), I could call _request_firmware() with "uevent" set to 0? This would force for former behavior?
Does "nowait" also have to be 0? I don't quite understand the separation between uevent and nowait.
Thanks! George
| |