From: Shuming Fan shumingf@realtek.com
[ Upstream commit 9adf2de86611ac108d07e769a699556d87f052e2 ]
This patch updates the settings to fix the speaker noise.
Signed-off-by: Shuming Fan shumingf@realtek.com Link: https://patch.msgid.link/20250602085851.4081886-1-shumingf@realtek.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org ---
**YES**
This commit should be backported to stable kernel trees. Here's my extensive analysis:
## Analysis of Code Changes
The commit modifies the `rt1320_vc_blind_write` array, which contains critical audio initialization settings for the RT1320 version C audio amplifier chip. The specific changes are:
1. **Register 0x1000db00**: Value changed from `0x04` to `0x07` 2. **New registers added**: 0x1000db15 through 0x1000db23 with specific coefficient values
## Why This Should Be Backported
### 1. **Critical Audio Quality Issue** This directly addresses speaker noise at 100% volume, which is a significant user experience problem. Looking at the similar commits in the reference examples, this aligns with "Similar Commit #1" (marked YES) which fixed "random louder sound" in RT1308-SDW. Both commits: - Fix audio quality issues that directly affect users - Modify vendor-specific register settings - Address problems with volume control/audio output
### 2. **Small, Contained, Low-Risk Fix** The changes are minimal and highly targeted: - Only modifies initialization register values in a lookup table - No architectural changes or new features - Limited to the RT1320 VC chip variant specifically - Changes are applied during device initialization only
### 3. **Hardware-Level Bug Fix** The register addresses (0x1000db00-0x1000db23) are in the DSP/firmware patch area, indicating this fixes a hardware-level audio processing issue. These appear to be audio coefficient or speaker protection parameters that prevent distortion at maximum volume.
### 4. **Follows Stable Tree Criteria** This commit meets all stable tree requirements: - ✅ **Important bugfix**: Fixes audible speaker noise affecting user experience - ✅ **Minimal risk**: Only changes register initialization values - ✅ **Confined scope**: Limited to RT1320 VC audio amplifier - ✅ **No new features**: Pure bug fix for existing functionality - ✅ **Clear impact**: Eliminates speaker noise at 100% volume
### 5. **Clear User Impact** Users with RT1320 VC amplifiers (commonly found in modern laptops/devices) would experience: - **Before**: Audible noise/distortion when volume is at 100% - **After**: Clean audio output at all volume levels including maximum
### 6. **Pattern Matching with Approved Backports** This closely matches "Similar Commit #1" which was marked for backporting (YES). Both commits: - Fix audio output quality issues - Use vendor registers to resolve problems - Address volume-related audio artifacts - Have minimal code impact with targeted register changes
The commit represents exactly the type of important, low-risk hardware compatibility fix that stable trees are designed to include.
sound/soc/codecs/rt1320-sdw.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-)
diff --git a/sound/soc/codecs/rt1320-sdw.c b/sound/soc/codecs/rt1320-sdw.c index d83b236a04503..4953f554caf08 100644 --- a/sound/soc/codecs/rt1320-sdw.c +++ b/sound/soc/codecs/rt1320-sdw.c @@ -204,7 +204,7 @@ static const struct reg_sequence rt1320_vc_blind_write[] = { { 0x3fc2bfc0, 0x03 }, { 0x0000d486, 0x43 }, { SDW_SDCA_CTL(FUNC_NUM_AMP, RT1320_SDCA_ENT_PDE23, RT1320_SDCA_CTL_REQ_POWER_STATE, 0), 0x00 }, - { 0x1000db00, 0x04 }, + { 0x1000db00, 0x07 }, { 0x1000db01, 0x00 }, { 0x1000db02, 0x11 }, { 0x1000db03, 0x00 }, @@ -225,6 +225,21 @@ static const struct reg_sequence rt1320_vc_blind_write[] = { { 0x1000db12, 0x00 }, { 0x1000db13, 0x00 }, { 0x1000db14, 0x45 }, + { 0x1000db15, 0x0d }, + { 0x1000db16, 0x01 }, + { 0x1000db17, 0x00 }, + { 0x1000db18, 0x00 }, + { 0x1000db19, 0xbf }, + { 0x1000db1a, 0x13 }, + { 0x1000db1b, 0x09 }, + { 0x1000db1c, 0x00 }, + { 0x1000db1d, 0x00 }, + { 0x1000db1e, 0x00 }, + { 0x1000db1f, 0x12 }, + { 0x1000db20, 0x09 }, + { 0x1000db21, 0x00 }, + { 0x1000db22, 0x00 }, + { 0x1000db23, 0x00 }, { 0x0000d540, 0x01 }, { 0x0000c081, 0xfc }, { 0x0000f01e, 0x80 },