[bardliao]

To address review comments form sashiko-bot@kernel.org
https://sashiko.dev/#/patchset/20261102060437.824814-1-yung-chuan.liao@linux.intel.com?part=2

[Copilot]

🟢 Approval recommended

The SoundWire bandwidth-allocation changes have no active review issues blocking approval.

No open issues 🎉

What changed in this PR

This follow-up refines SoundWire bandwidth allocation for multi-link failure handling by explicitly distinguishing stream preparation from depreparation.

Changes:

• Add a prepare flag to the bandwidth-computation interface and update callers and controller callbacks.
• Include the current stream in preparation calculations even when its state is still DEPREPARED.
• Limit lane selection to the stream being prepared and clear stale lane assignments when preparing on lane 0.

File	Description
include/​linux/​soundwire/​sdw.h	Extend and document the computation interface with the prepare flag.
drivers/​soundwire/​stream.c	Pass the appropriate flag during preparation and depreparation.
drivers/​soundwire/​qcom.c	Update the Qualcomm callback signature to match the interface.
drivers/​soundwire/​generic_bandwidth_allocation.c	Adjust stream inclusion and lane assignment using explicit preparation context.
drivers/​soundwire/​amd_manager.c	Update the AMD callback signature to match the interface.

_{Review effort: Balanced}

[ujfalusi]

I'm not sure if I follow all the changes, I guess I should trust your testing?

[ujfalusi]

on deprepare you don't need to re-compute ? Remove the leaving bandwidth use?

'Only compute the m_lane when preparing the current stream' ?

[bardliao]

We do re-compute the required clock rate. Only get_manager_lane() is skipped here. The lane bandwidth was computed at _sdw_deprepare_stream(). https://github.com/thesofproject/linux/blob/topic/sof-dev/drivers/soundwire/stream.c#L1814

[ujfalusi]

Now, this is hard to decode....

[bardliao]

_sdw_prepare_stream() could be called when stream->state = SDW_STREAM_CONFIGURED, SDW_STREAM_DEPREPARED or SDW_STREAM_DISABLED, but the previous code only test if (stream->state != SDW_STREAM_CONFIGURED), that skip the case when _sdw_prepare_stream() is called when stream state transfers from deprepare → prepare to prepare. Therefore, I changed the if (stream->state != SDW_STREAM_CONFIGURED) condition to if (prepare) and merge the all of the conditions together. I am happy to change it to

if (m_rt->stream == stream) {
    if (!prepare)
        continue;
} else {
    if (m_rt->stream->state != SDW_STREAM_ENABLED &&
        m_rt->stream->state != SDW_STREAM_PREPARED &&
        m_rt->stream->state != SDW_STREAM_DISABLED)
        continue;
}