[PATCH 5.10.y] usb: typec: ucsi: acpi: Assume UCSI 1.2 on Acer Nitro ANV15-41

[Sasha Levin <sashal@kernel.org>]

From: Pannarat Wiriyaarritham <pannarat.wiriyaarritham@danielcorp.dev>

[ Upstream commit 8c51ea651d043c786c37668c51624bd6b338a0ef ]

The Acer Nitro ANV15-41 exposes a functional UCSI ACPI PPM but
reports a UCSI VERSION value of zero.

ucsi_register() rejects a zero version with -ENODEV, leaving the
system without registered USB Type-C connectors.

The PPM works correctly when using the UCSI 1.2 layout. With UCSI
1.2 assumed, both Type-C connectors register correctly and USB Power
Delivery negotiation works.

Add a DMI-specific UCSI operation for the Acer Nitro ANV15-41 that
substitutes UCSI 1.2 only when firmware reports a zero version.
Preserve any valid non-zero firmware version.

Tested on an Acer Nitro ANV15-41 with BIOS V1.51.

Fixes: c1b0bc2dabfa ("usb: typec: Add support for UCSI interface")
Cc: stable <stable@kernel.org>
Assisted-by: LLM
Signed-off-by: Pannarat Wiriyaarritham <pannarat.wiriyaarritham@danielcorp.dev>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://patch.msgid.link/20260910023338.31816-1-pannarat.wiriyaarritham@danielcorp.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ sashal: Replaced the dedicated read_version callback with a DMI-gated check in ucsi_acpi_read(). ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/typec/ucsi/ucsi_acpi.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/usb/typec/ucsi/ucsi_acpi.c b/drivers/usb/typec/ucsi/ucsi_acpi.c
index 0c88d5bf09cae..17567bd134d11 100644
--- a/drivers/usb/typec/ucsi/ucsi_acpi.c
+++ b/drivers/usb/typec/ucsi/ucsi_acpi.c
@@ -9,6 +9,7 @@
 #include <linux/platform_device.h>
 #include <linux/module.h>
 #include <linux/acpi.h>
+#include <linux/dmi.h>
 
 #include "ucsi.h"
 
@@ -25,6 +26,16 @@ struct ucsi_acpi {
 	guid_t guid;
 };
 
+static const struct dmi_system_id ucsi_acpi_quirks[] = {
+	{
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Nitro ANV15-41"),
+		},
+	},
+	{ }
+};
+
 static int ucsi_acpi_dsm(struct ucsi_acpi *ua, int func)
 {
 	union acpi_object *obj;
@@ -45,6 +56,7 @@ static int ucsi_acpi_read(struct ucsi *ucsi, unsigned int offset,
 			  void *val, size_t val_len)
 {
 	struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);
+	u16 *version = val;
 	int ret;
 
 	ret = ucsi_acpi_dsm(ua, UCSI_DSM_FUNC_READ);
@@ -53,6 +65,12 @@ static int ucsi_acpi_read(struct ucsi *ucsi, unsigned int offset,
 
 	memcpy(val, (const void __force *)(ua->base + offset), val_len);
 
+	if (offset == UCSI_VERSION && val_len == sizeof(*version) && !*version &&
+	    dmi_check_system(ucsi_acpi_quirks)) {
+		dev_warn(ua->dev, "UCSI version is zero, assuming 1.2\n");
+		*version = 0x0120;
+	}
+
 	return 0;
 }
 
-- 
2.53.0