Re: [PATCH v2 0/6] USB: serial: use wrappers for usb_control_msg()

From: Johan Hovold
Date: Tue Sep 21 2021 - 07:10:15 EST


On Mon, Aug 02, 2021 at 02:01:16AM +0530, Himadri Pandya wrote:
> There are many usages of usb_control_msg() that can use the new wrapper
> functions usb_contro_msg_send() & usb_control_msg_recv() for better
> error checks on short reads and writes.

As I said before, there no need to worry about short writes as that will
always return an error. So this description (and some of the commit
messages) needs a bit of work.

> They can also be used to avoid
> allocating redundant dma buffers that are generally required to use
> usb_control_msg().

The DMA buffers are anything but redundant; they are required. But the
wrappers can be used to not have to manage the dma buffers explicitly.

> Hence use them whenever possible and avoid using
> usb_control_msg() directly.
>
> Changes in v2:
> - Drop unnecessary use of wrappers
> - Drop unrelated style changes
>
> Additional Info:
> - This is a super late follow-up on v1 that was submitted a while
> ago(my sincere apologies). (All patches are rebased and
> compile tested.)
> - v1 patches: https://lkml.org/lkml/2020/11/4/40
> - Patches that introduced the wrapper functions:
> https://lkml.org/lkml/2020/9/14/859

No worries, I'll go review the patches now.

Johan