Re: [PATCH 2/2] scsi: ufs: core: Add support to retrieve and store TX Equalization settings

From: Can Guo

Date: Thu Apr 23 2026 - 09:50:13 EST


Hi Bart,

On 4/21/2026 12:28 AM, Bart Van Assche wrote:
On 4/20/26 6:23 AM, Can Guo wrote:
The usage of the two Selectors is not limited to above examples. Yet it is hard to get
aligned on how to use the two Selectors across different companies. Hence I am adding
a module parameter.

These kernel module parameters can be converted into sysfs attributes,
isn't it? Converting these kernel module parameters into sysfs
attributes has the advantage that different values can be configured per
host controller in systems with multiple UFS host controllers.
Thanks for the suggestion.

For this series, these knobs are needed before the first HS-G6 power mode change,
which happens during early UFS bring-up in probe. At that point, userspace-driven
sysfs attributes are not available yet, so relying only on sysfs would miss the first
power mode transition.

That is why this patch uses module parameters (boot-time configurable via kernel
command line).

I agree sysfs is better for per-host runtime tuning on multi-controller systems.
We can add per-host sysfs controls as a follow-up later on, while keeping boot-time
defaults through module parameters for the first-transition requirement.

Thanks,
Can Guo.

Thanks,

Bart.