Re: [PATCH 5.15 005/570] ALSA: usb-audio: Remove VALIDATE_RATES quirk for Focusrite devices

Geoffrey D. Bennett
2026-04-13T17:36:42Z

On Mon, Apr 13, 2026 at 05:52:16PM +0200, Greg Kroah-Hartman wrote:
> 5.15-stable review patch. If anyone has any objections, please let me know.
>
> ------------------
>
> From: Geoffrey D. Bennett <g@b4.vu>
>
> [ Upstream commit a8cc55bf81a45772cad44c83ea7bb0e98431094a ]
>
> Remove QUIRK_FLAG_VALIDATE_RATES for Focusrite. With the previous
> commit, focusrite_valid_sample_rate() produces correct rate tables
> without USB probing.

Hi Greg,

This commit depends on its predecessor 24d2d3c5f940 ("ALSA: usb-audio:
Improve Focusrite sample rate filtering") which was not picked up for
stable because it didn't have a Fixes tag. It has been added to 6.19
and 6.18 but not 6.12, 6.6, 6.1, 5.15.

Without the rate filtering patch, the Focusrite Scarlett 18i8 3rd Gen
gets all sample rates advertised on every altsetting instead of the
correct per-altsetting subset.

There are also subsequent fixes:

a0dafdbd1049 ALSA: usb-audio: Exclude Scarlett 2i2 1st Gen (8016) from SKIP_IFACE_SETUP
f025ac8c698a ALSA: usb-audio: Exclude Scarlett Solo 1st Gen from SKIP_IFACE_SETUP
990a8b0732cf ALSA: usb-audio: Exclude Scarlett 2i4 1st Gen from SKIP_IFACE_SETUP
8780f561f671 ALSA: usb-audio: Exclude Scarlett 2i2 1st Gen from SKIP_IFACE_SETUP

and a just-submitted fix for the Scarlett 18i20 1st Gen.

Regards,
Geoffrey.