[PATCH AUTOSEL 6.16-6.12] platform/x86/amd/pmf: Support new ACPI ID AMDI0108

[Sasha Levin <sashal@kernel.org>]

From: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>

[ Upstream commit 1b09d08866277677d11726116f5e786d5ba00173 ]

Include the ACPI ID AMDI0108, which is used on upcoming AMD platforms, in
the PMF driver's list of supported devices.

Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Link: https://patch.msgid.link/20250915090546.2759130-1-Shyam-sundar.S-k@amd.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

LLM Generated explanations, may be completely bogus:

Based on my exhaustive investigation, here is my determination:

**Backport Status: YES**

## Extensive Analysis

This commit adds a single line (`{"AMDI0108", 0},`) to the ACPI device
ID table in the AMD Platform Management Framework (PMF) driver at line
405 of `drivers/platform/x86/amd/pmf/core.c`.

### Key Evidence Supporting Backporting:

1. **Stable Kernel Rules Explicitly Allow It**:
   Documentation/process/stable-kernel-rules.rst specifically states
   that patches that "just add a device ID" are acceptable for stable
   backports, even if they don't fix a bug that currently affects users.

2. **Established Precedent**: My research reveals that ALL previous AMD
   PMF ACPI ID additions were successfully backported:
   - AMDI0107 (July 2024) → Backported to 6.10.y stable
   - AMDI0105 (May 2024) → Backported to 6.10.y stable
   - AMDI0103 (July 2023) → Backported to 6.6.y and 6.8.y stable
   These were all picked up by the AUTOSEL process without explicit Cc:
stable tags.

3. **Minimal Risk**: The change is a single-line addition to a static
   ACPI ID table with `driver_data = 0`, indicating standard support
   (not experimental like AMDI0100 which requires force_load). This
   follows the exact pattern of AMDI0102 through AMDI0107.

4. **Hardware Enablement Value**: The PMF driver manages critical
   platform features including:
   - Power management and thermal controls
   - Performance optimization
   - Smart PC capabilities
   - Dynamic power profiles
   Without this ACPI ID, upcoming AMD platforms with AMDI0108 identifier
will lack these essential functionalities.

5. **No Architectural Changes**: The commit makes no functional changes
   to the driver's logic, only adds recognition for a new hardware
   identifier. The existing code paths at lines 401-409 (ACPI device
   matching) and the rest of the driver remain unchanged.

6. **Clear Vendor Support**: The patch comes from Shyam Sundar S K (AMD
   engineer who maintains this driver) and is reviewed by Mario
   Limonciello (AMD), indicating this is an official AMD hardware
   enablement effort.

### Code Analysis:
The addition at line 405 maintains the existing array structure and
follows the pattern of previous IDs. The `driver_data = 0` indicates
this is a fully supported platform (unlike AMDI0100 at line 400 which
has `driver_data = 0x100` requiring the force_load parameter check at
line 422).

Given the established pattern of backporting such changes, the minimal
risk, and the explicit allowance in stable kernel rules for device ID
additions, this commit should be backported to stable kernel trees to
ensure upcoming AMD platforms have PMF support in stable kernels.

 drivers/platform/x86/amd/pmf/core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/platform/x86/amd/pmf/core.c b/drivers/platform/x86/amd/pmf/core.c
index ef988605c4da6..bc544a4a5266e 100644
--- a/drivers/platform/x86/amd/pmf/core.c
+++ b/drivers/platform/x86/amd/pmf/core.c
@@ -403,6 +403,7 @@ static const struct acpi_device_id amd_pmf_acpi_ids[] = {
 	{"AMDI0103", 0},
 	{"AMDI0105", 0},
 	{"AMDI0107", 0},
+	{"AMDI0108", 0},
 	{ }
 };
 MODULE_DEVICE_TABLE(acpi, amd_pmf_acpi_ids);
-- 
2.51.0