Public bug reported:

[Impact]
No audio from right built-in speaker on systems with TAS2781 SPI audio codec.

The TAS2781 SPI driver performs an unnecessary device reset check during
probe that causes the firmware download to be skipped when the device is
in its default state. This results in the audio codec not being properly
initialized, leaving the right speaker non-functional.

The issue affects systems using TAS2781 audio codec connected via SPI
interface during boot and device initialization.

[Fix]
Remove the unnecessary reset status check in the SPI driver probe function and 
force firmware download unconditionally, matching the behavior of the I2C 
device variant.

The patch removes the TAS2781_REG_CLK_CONFIG register read and the
conditional check that prevented firmware loading when the device was
already in default state. Since the device should always be in the
default state during SPI driver probe, the status check serves no
purpose and incorrectly blocks the required firmware initialization.

Upstream commit: 908ef80e31e4d3bd953a0088fe57640cd9ae7b3e (linux-next)
Link: https://patch.msgid.link/[email protected]

[Test Plan]
On a system with TAS2781 SPI audio codec:
1. Boot the system with the patched kernel
2. Check the kernel log for successful firmware loading:
      $ dmesg | grep -i tas2781
      Expected: No "FW download failed" errors
   
3. Test audio playback to the right speaker:
      $ speaker-test -c 2 -t wav
   
Without the patch: Right speaker produces no sound, firmware may fail to load
With the patch: Both left and right speakers work correctly, firmware loads 
successfully

[Where problems could occur]
It may break the ALSA HDA TAS2781 audio codec driver for SPI devices.

If the forced firmware download is incorrect for certain hardware
variants or initialization states, it could cause firmware loading
failures, audio distortion, or speaker damage in edge cases where the
device shouldn't be reinitialized. This would manifest as audio playback
failures, kernel error messages about firmware download failures, or
incorrect audio output routing.

The patch removes error handling paths that could potentially protect
against unexpected device states. If the device is ever in a state where
firmware shouldn't be loaded (though according to the patch rationale
this shouldn't happen during probe), it could lead to audio subsystem
instability.

However, the patch has been reviewed and approved by the ALSA maintainer
(Takashi Iwai) and is in linux-next, indicating thorough upstream
review.

** Affects: hwe-next
     Importance: Undecided
         Status: New

** Affects: linux-oem-6.17 (Ubuntu)
     Importance: Undecided
         Status: New

** Affects: linux-oem-6.17 (Ubuntu Noble)
     Importance: Undecided
     Assignee: AceLan Kao (acelankao)
         Status: In Progress


** Tags: jira-stella-3075 oem-priority stella

** Also affects: linux-oem-6.17 (Ubuntu Noble)
   Importance: Undecided
       Status: New

** Changed in: linux-oem-6.17 (Ubuntu Noble)
       Status: New => In Progress

** Changed in: linux-oem-6.17 (Ubuntu Noble)
     Assignee: (unassigned) => AceLan Kao (acelankao)

** Tags added: jira-stella-3075 oem-priority stella

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https://bugs.launchpad.net/bugs/2141639

Title:
  ALSA: hda/tas2781 Audio Fix for the front-right speacker

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