Re: [PATCH RFC] drivers/rufs: add Rust UFS host controller driver

From: Bart Van Assche

Date: Mon Sep 14 2026 - 16:33:38 EST


On 9/12/26 5:30 PM, Bart Van Assche wrote:
On 9/12/26 8:45 AM, Andreas Hindborg wrote:
If we expected this new driver to be a strict subset of ufshcd, we would
not build it. The reason to do it is the features that do not fit the
scsi midlayer.

That's a super vague statement. What features do you want to implement
that do not fit the SCSI mid-layer? If this is about implementing non-
standard SCSI commands, REQ_OP_DRV_IN and REQ_OP_DRV_OUT should be
sufficient, isn't it? Please note that this is not an endorsement for
implementing non-standard commands in UFS devices. Non-standard storage
commands complicate filesystem development and maintenance, especially
if which commands are supported depends on both the manufacturer of the
storage device and the device model.
(replying to my own e-mail)

Since my question has not been answered, I assume that REQ_OP_DRV_IN and
REQ_OP_DRV_OUT are sufficient. If REQ_OP_DRV_IN and REQ_OP_DRV_OUT are
sufficient, there is no longer a reason to implement a new UFS driver
subsystem because the upstream UFS driver already supports these
operations, isn't it?

Bart.