[opus] proper limit and error code for opus decoder instances (#4384)

- [x] I have read and followed the [Contribution Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/CONTRIBUTING.md#code-contributions).
- [x] I have read and followed the [AI Policy](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/AI.md)
- [x] I have read and followed the [Coding Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/Coding.md) to the best of my ability.

-------------------

This is intended to fix Hades II save loading issue.

By analyzing panic dump it was found out that the error code was 0x160A. By decoding firmware it was found that error comes from 'nn::codec::InitializeHardwareOpusDecoder'.

Further decoding revealed that SDK tries to allocate multiple opus instances, up to the fw limit of 24 instances, and when it receives return error ResultOutOfOpusDecoders (385), a software fallback is gracefully used.

Implementing the limitation and the limit reached error code return makes saves load properly, multiple times in a row in both windows and android.

I still wonder why the game allocates too many parallel instances, but the current implementation is a real fw compliant solution, and whether the 24+ is real or some leak may be investigated later, or not.

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4384
Reviewed-by: lizzie <lizzie@eden-emu.dev>
Reviewed-by: MaranBr <maranbr@eden-emu.dev>

1 files changed, 2 insertions, 1 deletions

diff --git a/src/core/hle/service/audio/errors.h b/src/core/hle/service/audio/errors.h
index 8062820de3..553b4ee360 100644
--- a/src/core/hle/service/audio/errors.h
+++ b/src/core/hle/service/audio/errors.h
@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 // SPDX-FileCopyrightText: Copyright 2019 yuzu Emulator Project
@@ -33,6 +33,7 @@ constexpr Result ResultLibOpusInternalError{ErrorModule::HwOpus, 4};
 constexpr Result ResultBufferTooSmall{ErrorModule::HwOpus, 3};
 constexpr Result ResultLibOpusBadArg{ErrorModule::HwOpus, 2};
 constexpr Result ResultInvalidOpusDSPReturnCode{ErrorModule::HwOpus, 259};
+constexpr Result ResultOutOfOpusDecoders{ErrorModule::HwOpus, 385};
 constexpr Result ResultInvalidOpusSampleRate{ErrorModule::HwOpus, 1001};
 constexpr Result ResultInvalidOpusChannelCount{ErrorModule::HwOpus, 1002};