5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Pannarat Wiriyaarritham [ 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 Assisted-by: LLM Signed-off-by: Pannarat Wiriyaarritham Reviewed-by: Heikki Krogerus Link: https://patch.msgid.link/20260910023338.31816-1-pannarat.wiriyaarritham@danielcorp.dev Signed-off-by: Greg Kroah-Hartman [ sashal: Moved the read_version callback logic into ucsi_acpi_read() because the dedicated callback is unavailable. ] Signed-off-by: Sasha Levin --- 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 #include #include +#include #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