From: Amit Sunil Dhamne amitsd@google.com
Register read of TCPC_RX_BYTE_CNT returns the total size consisting of:
PD message (pending read) size + 1 Byte for Frame Type (SOP*)
This is validated against the max PD message (`struct pd_message`) size without accounting for the extra byte for the frame type. Note that the struct pd_message does not contain a field for the frame_type. This results in false negatives when the "PD message (pending read)" is equal to the max PD message size.
Fixes: 6f413b559f86 ("usb: typec: tcpci_maxim: Chip level TCPC driver") Signed-off-by: Amit Sunil Dhamne amitsd@google.com Signed-off-by: Badhri Jagan Sridharan badhri@google.com Reviewed-by: Kyle Tso kyletso@google.com --- drivers/usb/typec/tcpm/tcpci_maxim_core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/typec/tcpm/tcpci_maxim_core.c b/drivers/usb/typec/tcpm/tcpci_maxim_core.c index fd1b80593367641a6f997da2fb97a2b7238f6982..648311f5e3cf135f23b5cc0668001d2f177b9edd 100644 --- a/drivers/usb/typec/tcpm/tcpci_maxim_core.c +++ b/drivers/usb/typec/tcpm/tcpci_maxim_core.c @@ -166,7 +166,8 @@ static void process_rx(struct max_tcpci_chip *chip, u16 status) return; }
- if (count > sizeof(struct pd_message) || count + 1 > TCPC_RECEIVE_BUFFER_LEN) { + if (count > sizeof(struct pd_message) + 1 || + count + 1 > TCPC_RECEIVE_BUFFER_LEN) { dev_err(chip->dev, "Invalid TCPC_RX_BYTE_CNT %d\n", count); return; }
--- base-commit: ebd297a2affadb6f6f4d2e5d975c1eda18ac762d change-id: 20250421-b4-new-fix-pd-rx-count-79297ba619b7
Best regards,