6.6-stable review patch. If anyone has any objections, please let me know.
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From: Christian A. Ehrhardt lk@c--e.de
commit 2840143e393a4ddc1caab4372969ea337371168c upstream.
In case of a spurious or otherwise delayed notification it is possible that CCI still reports the previous completion. The UCSI spec is aware of this and provides two completion bits in CCI, one for normal commands and one for acks. As acks and commands alternate the notification handler can determine if the completion bit is from the current command.
The initial UCSI code correctly handled this but the distinction between the two completion bits was lost with the introduction of the new API.
To fix this revive the ACK_PENDING bit for ucsi_acpi and only complete commands if the completion bit matches.
Fixes: f56de278e8ec ("usb: typec: ucsi: acpi: Move to the new API") Cc: stable@vger.kernel.org Signed-off-by: "Christian A. Ehrhardt" lk@c--e.de Acked-by: Heikki Krogerus heikki.krogerus@linux.intel.com Link: https://lore.kernel.org/r/20240121204123.275441-3-lk@c--e.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/typec/ucsi/ucsi_acpi.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-)
--- a/drivers/usb/typec/ucsi/ucsi_acpi.c +++ b/drivers/usb/typec/ucsi/ucsi_acpi.c @@ -73,9 +73,13 @@ static int ucsi_acpi_sync_write(struct u const void *val, size_t val_len) { struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi); + bool ack = UCSI_COMMAND(*(u64 *)val) == UCSI_ACK_CC_CI; int ret;
- set_bit(COMMAND_PENDING, &ua->flags); + if (ack) + set_bit(ACK_PENDING, &ua->flags); + else + set_bit(COMMAND_PENDING, &ua->flags);
ret = ucsi_acpi_async_write(ucsi, offset, val, val_len); if (ret) @@ -85,7 +89,10 @@ static int ucsi_acpi_sync_write(struct u ret = -ETIMEDOUT;
out_clear_bit: - clear_bit(COMMAND_PENDING, &ua->flags); + if (ack) + clear_bit(ACK_PENDING, &ua->flags); + else + clear_bit(COMMAND_PENDING, &ua->flags);
return ret; } @@ -142,8 +149,10 @@ static void ucsi_acpi_notify(acpi_handle if (UCSI_CCI_CONNECTOR(cci)) ucsi_connector_change(ua->ucsi, UCSI_CCI_CONNECTOR(cci));
- if (test_bit(COMMAND_PENDING, &ua->flags) && - cci & (UCSI_CCI_ACK_COMPLETE | UCSI_CCI_COMMAND_COMPLETE)) + if (cci & UCSI_CCI_ACK_COMPLETE && test_bit(ACK_PENDING, &ua->flags)) + complete(&ua->complete); + if (cci & UCSI_CCI_COMMAND_COMPLETE && + test_bit(COMMAND_PENDING, &ua->flags)) complete(&ua->complete); }