Hello, [dropped christoph.muellner@theobroma-systems.com from Cc: as the address doesn't seem to work any more] On Thu, Feb 04, 2021 at 11:11:56AM -0500, Eric Tremblay wrote: > The patch introduce the UART_CAP_NOTEMT capability. The capability > indicate that the UART doesn't have an interrupt available on TEMT. > > In the case where the device does not support it, we calculate the > maximum time it could take for the transmitter to empty the > shift register. When we get in the situation where we get the > THRE interrupt, we check if the TEMT bit is set. If it's not, we start > the a timer and recall __stop_tx() after the delay. > > The transmit sequence is a bit modified when the capability is set. The > new timer is used between the last interrupt(THRE) and a potential > stop_tx timer. I wonder if the required change can be simplified by just increasing the stop_tx_timer timeout as there is nothing that has to happen when the shifter is empty apart from starting the stop_tx timer. This would require a good documentation because the semantic of the stop timer would change. @Eric: Do you plan to address the feedback comments here? I'd volunteer as a tester if yes. Otherwise there might be some incentive to work on this series myself. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | https://www.pengutronix.de/ |