From: Azamat Almazbek uulu <almazbek1608@gmail.com>

[ Upstream commit 32fc4168fa56f6301d858c778a3d712774e9657e ]

The ASUS ExpertBook BM1503CDA (Ryzen 5 7535U, Barcelo-R) has an
internal DMIC connected through the AMD ACP (Audio CoProcessor)
but is missing from the DMI quirk table, so the acp6x machine
driver probe returns -ENODEV and no DMIC capture device is created.

Add the DMI entry so the internal microphone works out of the box.

Signed-off-by: Azamat Almazbek uulu <almazbek1608@gmail.com>
Reviewed-by: Vijendar Mukunda <Vijendar.Mukunda@amd.com>
Link: https://patch.msgid.link/20260221114813.5610-1-almazbek1608@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

LLM Generated explanations, may be completely bogus:

## Analysis: ASoC: amd: yc: Add ASUS EXPERTBOOK BM1503CDA to quirk table

### What the commit does

This is a simple DMI quirk table addition — a 7-line entry adding the
ASUS EXPERTBOOK BM1503CDA to the `yc_acp_quirk_table[]` in
`sound/soc/amd/yc/acp6x-mach.c`. Without this entry, the internal DMIC
(digital microphone) on this laptop is not detected, and the driver
probe returns `-ENODEV`, meaning **no microphone capture device is
created** — the internal mic simply doesn't work.

### Stable kernel criteria assessment

1. **Fixes a real bug**: Yes — the internal microphone doesn't work on
   this specific laptop model without the quirk entry.
2. **Obviously correct and tested**: Yes — it's a trivial DMI match
   entry following the exact same pattern as dozens of other entries in
   the same table. Reviewed by the AMD audio maintainer (Vijendar
   Mukunda).
3. **Small and contained**: Yes — 7 lines added to a single file, no
   logic changes whatsoever.
4. **No new features**: Correct — this enables existing hardware support
   on a specific device, not a new feature.
5. **Exception category**: This falls squarely under **hardware
   quirks/workarounds** — one of the explicitly allowed categories for
   stable backports.

### Risk assessment

- **Risk**: Essentially zero. The DMI match is specific to one laptop
  model (`ASUS EXPERTBOOK BM1503CDA` from `ASUSTeK COMPUTER INC.`). It
  cannot affect any other hardware.
- **Benefit**: Internal microphone works on this laptop model.
- **Dependencies**: None — the driver and quirk table infrastructure
  already exist in stable trees.

### Verification

- Verified the diff is a pure DMI table entry addition (7 lines) with no
  logic changes.
- Verified the entry follows the identical pattern of all other entries
  in the table (DMI_MATCH on BOARD_VENDOR + PRODUCT_NAME, driver_data =
  &acp6x_card).
- Verified the commit has `Reviewed-by: Vijendar Mukunda
  <Vijendar.Mukunda@amd.com>` (AMD audio subsystem reviewer).
- The file `sound/soc/amd/yc/acp6x-mach.c` and the `yc_acp_quirk_table`
  have existed in stable trees — this is a mature driver with many
  similar quirk entries.

### Conclusion

This is a textbook stable backport candidate: a hardware quirk addition
that enables an internal microphone on a specific laptop. Zero risk,
clear user benefit, trivially correct.

**YES**

 sound/soc/amd/yc/acp6x-mach.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/sound/soc/amd/yc/acp6x-mach.c b/sound/soc/amd/yc/acp6x-mach.c
index f1a63475100d1..7af4daeb4c6ff 100644
--- a/sound/soc/amd/yc/acp6x-mach.c
+++ b/sound/soc/amd/yc/acp6x-mach.c
@@ -703,6 +703,13 @@ static const struct dmi_system_id yc_acp_quirk_table[] = {
 				DMI_MATCH(DMI_PRODUCT_NAME, "Vivobook_ASUSLaptop M6501RR_M6501RR"),
 			}
 		},
+	{
+		.driver_data = &acp6x_card,
+		.matches = {
+			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK COMPUTER INC."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "ASUS EXPERTBOOK BM1503CDA"),
+		}
+	},
 	{}
 };
 
-- 
2.51.0