From: "Christian A. Ehrhardt" lk@c--e.de
[ Upstream commit f3be347ea42dbb0358cd8b2d8dc543a23b70a976 ]
The PPM on some Dell laptops seems to expect that the ACK_CC_CI command to clear the connector change notification is in turn followed by another ACK_CC_CI to acknowledge the ACK_CC_CI command itself. This is in violation of the UCSI spec that states:
"The only notification that is not acknowledged by the OPM is the command completion notification for the ACK_CC_CI or the PPM_RESET command."
Add a quirk to send this ack anyway. Apply the quirk to all Dell systems.
On the first command that acks a connector change send a dummy command to determine if it runs into a timeout. Only activate the quirk if it does. This ensure that we do not break Dell systems that do not need the quirk.
Signed-off-by: "Christian A. Ehrhardt" lk@c--e.de Reviewed-by: Heikki Krogerus heikki.krogerus@linux.intel.com Link: https://lore.kernel.org/r/20240121204123.275441-4-lk@c--e.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/usb/typec/ucsi/ucsi_acpi.c | 71 ++++++++++++++++++++++++++++-- 1 file changed, 68 insertions(+), 3 deletions(-)
diff --git a/drivers/usb/typec/ucsi/ucsi_acpi.c b/drivers/usb/typec/ucsi/ucsi_acpi.c index 6bbf490ac401..5fbd5a218341 100644 --- a/drivers/usb/typec/ucsi/ucsi_acpi.c +++ b/drivers/usb/typec/ucsi/ucsi_acpi.c @@ -25,6 +25,8 @@ struct ucsi_acpi { unsigned long flags; guid_t guid; u64 cmd; + bool dell_quirk_probed; + bool dell_quirk_active; };
static int ucsi_acpi_dsm(struct ucsi_acpi *ua, int func) @@ -119,12 +121,73 @@ static const struct ucsi_operations ucsi_zenbook_ops = { .async_write = ucsi_acpi_async_write };
-static const struct dmi_system_id zenbook_dmi_id[] = { +/* + * Some Dell laptops expect that an ACK command with the + * UCSI_ACK_CONNECTOR_CHANGE bit set is followed by a (separate) + * ACK command that only has the UCSI_ACK_COMMAND_COMPLETE bit set. + * If this is not done events are not delivered to OSPM and + * subsequent commands will timeout. + */ +static int +ucsi_dell_sync_write(struct ucsi *ucsi, unsigned int offset, + const void *val, size_t val_len) +{ + struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi); + u64 cmd = *(u64 *)val, ack = 0; + int ret; + + if (UCSI_COMMAND(cmd) == UCSI_ACK_CC_CI && + cmd & UCSI_ACK_CONNECTOR_CHANGE) + ack = UCSI_ACK_CC_CI | UCSI_ACK_COMMAND_COMPLETE; + + ret = ucsi_acpi_sync_write(ucsi, offset, val, val_len); + if (ret != 0) + return ret; + if (ack == 0) + return ret; + + if (!ua->dell_quirk_probed) { + ua->dell_quirk_probed = true; + + cmd = UCSI_GET_CAPABILITY; + ret = ucsi_acpi_sync_write(ucsi, UCSI_CONTROL, &cmd, + sizeof(cmd)); + if (ret == 0) + return ucsi_acpi_sync_write(ucsi, UCSI_CONTROL, + &ack, sizeof(ack)); + if (ret != -ETIMEDOUT) + return ret; + + ua->dell_quirk_active = true; + dev_err(ua->dev, "Firmware bug: Additional ACK required after ACKing a connector change.\n"); + dev_err(ua->dev, "Firmware bug: Enabling workaround\n"); + } + + if (!ua->dell_quirk_active) + return ret; + + return ucsi_acpi_sync_write(ucsi, UCSI_CONTROL, &ack, sizeof(ack)); +} + +static const struct ucsi_operations ucsi_dell_ops = { + .read = ucsi_acpi_read, + .sync_write = ucsi_dell_sync_write, + .async_write = ucsi_acpi_async_write +}; + +static const struct dmi_system_id ucsi_acpi_quirks[] = { { .matches = { DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), DMI_MATCH(DMI_PRODUCT_NAME, "ZenBook UX325UA_UM325UA"), }, + .driver_data = (void *)&ucsi_zenbook_ops, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), + }, + .driver_data = (void *)&ucsi_dell_ops, }, { } }; @@ -151,6 +214,7 @@ static int ucsi_acpi_probe(struct platform_device *pdev) { struct acpi_device *adev = ACPI_COMPANION(&pdev->dev); const struct ucsi_operations *ops = &ucsi_acpi_ops; + const struct dmi_system_id *id; struct ucsi_acpi *ua; struct resource *res; acpi_status status; @@ -180,8 +244,9 @@ static int ucsi_acpi_probe(struct platform_device *pdev) init_completion(&ua->complete); ua->dev = &pdev->dev;
- if (dmi_check_system(zenbook_dmi_id)) - ops = &ucsi_zenbook_ops; + id = dmi_first_match(ucsi_acpi_quirks); + if (id) + ops = id->driver_data;
ua->ucsi = ucsi_create(&pdev->dev, ops); if (IS_ERR(ua->ucsi))