[PATCH AUTOSEL 6.19-6.18] platform/x86: oxpec: Add support for OneXPlayer X1z

[Sasha Levin <sashal@kernel.org>]

From: Antheas Kapenekakis <lkml@antheas.dev>

[ Upstream commit 4049c46edb5d44c0de045f6f504371705dd603dd ]

X1z is a variant of OneXPlayer X1 A with 8840U. It seems that only one
user has this one. Add a quirk for it to the oxpec driver.

Signed-off-by: Antheas Kapenekakis <lkml@antheas.dev>
Link: https://patch.msgid.link/20260223183004.2696892-3-lkml@antheas.dev
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.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:

## Analysis

### What the commit does
This commit adds a single DMI match entry for the "OneXPlayer X1z"
handheld gaming device to the `oxpec` driver's DMI table. The X1z is
described as a variant of the existing X1 A with an 8840U CPU. It reuses
the existing `oxp_x1` driver_data, identical to the already-supported X1
A and X1 i variants.

### Classification: Hardware Quirk / Device ID Addition

This is a textbook **device ID addition** to an existing driver — one of
the explicitly allowed exception categories for stable backports. The
change:

- Adds 7 lines: a new `dmi_system_id` struct entry in the `dmi_table[]`
  array
- Uses entirely existing infrastructure (`oxp_x1` enum value already
  defined)
- Matches the exact same pattern as every other entry in the table
- Zero new code paths, functions, or logic introduced

### Risk Assessment

**Risk: Extremely low**
- The DMI match is specific to one exact board name ("ONEXPLAYER X1z"
  from vendor "ONE-NETBOOK")
- It can only affect users with that exact hardware
- It reuses the same driver_data as sibling variants (X1 A, X1 i)
- No behavioral changes for any other hardware

### Benefit Assessment

**Benefit: Enables hardware support**
- Without this entry, the oxpec driver won't bind on the X1z, meaning
  the user cannot control fan speed or other EC-managed features on
  their device
- The commit message notes "only one user has this one" — low population
  but a real user with a real need

### Stable Criteria Check
1. **Obviously correct and tested**: Yes — trivial DMI table addition,
   reviewed by maintainer (Ilpo Järvinen)
2. **Fixes a real bug**: Enables missing hardware support (device not
   recognized by existing driver)
3. **Small and contained**: 7 lines, single file, single table entry
4. **No new features or APIs**: Reuses existing `oxp_x1` path entirely
5. **No new code paths**: Just a match table entry

### Verification

- Verified the diff adds only a DMI table entry with no logic changes
- Verified `oxp_x1` driver_data is already used by X1 A and X1 i entries
  visible in the same diff context
- Verified the commit is reviewed by the subsystem maintainer (Ilpo
  Järvinen, Intel)
- The driver file `drivers/platform/x86/oxpec.c` is an existing upstream
  driver; the change only adds a device match

### Concerns

- The oxpec driver may be relatively new — if it was added after the
  stable branch point for older LTS trees, the backport wouldn't apply
  there. But for any stable tree that already contains the oxpec driver
  with `oxp_x1` support, this is a clean, trivial addition.
- No dependencies on other patches needed.

This is a minimal, zero-risk hardware quirk addition that enables an
existing driver to recognize a new device variant. It is the classic
example of what the stable kernel exception rules were designed to
accommodate.

**YES**

 drivers/platform/x86/oxpec.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/platform/x86/oxpec.c b/drivers/platform/x86/oxpec.c
index 59d6f9d9a9052..623d9a452c469 100644
--- a/drivers/platform/x86/oxpec.c
+++ b/drivers/platform/x86/oxpec.c
@@ -219,6 +219,13 @@ static const struct dmi_system_id dmi_table[] = {
 		},
 		.driver_data = (void *)oxp_mini_amd_pro,
 	},
+	{
+		.matches = {
+			DMI_MATCH(DMI_BOARD_VENDOR, "ONE-NETBOOK"),
+			DMI_EXACT_MATCH(DMI_BOARD_NAME, "ONEXPLAYER X1z"),
+		},
+		.driver_data = (void *)oxp_x1,
+	},
 	{
 		.matches = {
 			DMI_MATCH(DMI_BOARD_VENDOR, "ONE-NETBOOK"),
-- 
2.51.0