11 Apr
2015
11 Apr
'15
7:01 p.m.
On Thursday, April 09, 2015 at 05:27:49 AM, Stephen Warren wrote:
When fetching the first descriptor from a new device, only validate that we received at least 8 bytes, not that we received the entire descriptor. The reasoning is:
- The code only uses fields in the first 8 bytes, so that's all we need to have fetched at this stage.
- The smallest maxpacket size is 8 bytes. Before we know the actual maxpacket the device uses, the USB controller may only accept a single packet (see the DWC2 note in the comment added in the commit). Consequently we are only guaranteed to receive 1 packet (at least 8 bytes) even in a non-error case.
Fixes: 1a7758044b04 ("usb: Early failure when the first descriptor read fails or is invalid") Cc: Paul Kocialkowski contact@paulk.fr Signed-off-by: Stephen Warren swarren@wwwdotorg.org
Applied to u-boot-usb/next, thanks!
Best regards, Marek Vasut