request_firmware in DMA region

Lucas Tanure tanure at
Wed Mar 18 12:55:47 EDT 2020

On 2020-03-18 14:46, Greg KH wrote:
> On Wed, Mar 18, 2020 at 02:29:24PM +0000, Lucas Tanure wrote:
>> Hi,
>> I'm sending firmware to usb device with this code:
>> But it`s falling because the request firmware call didn't put my firmware in
>> a DMA capable area. That's my guess.
>> So how to request firmware in DMA capable area?
> kmalloc your buffer used for USB transfers.
Thanks, worked.
> Do you have a pointer to your driver anywhere?  The code you show below
> isn't in any kernel source that I can see.

I`m working to get permission for that.

Quick question: Why my usb driver doesn't unload after I disconnected it ?

This driver is meant to load a new firmware into the board only. And 
after the bootloader finished the download the board with show it self 
with a different vendor and product id.

All the firmware download in done in probe, so there is no need for this 
driver after that. Can my driver unload it self ?

> thanks,
> greg k-h



More information about the Kernelnewbies mailing list