| Message ID | 20230928151631.149333-2-jcmvbkbc@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | serial: add drivers for the ESP32xx serial devices | expand |
On Thu, Sep 28, 2023 at 08:16:27AM -0700, Max Filippov wrote: > uart_get_baud_rate has input parameters 'min' and 'max' limiting the > range of acceptable baud rates from the caller's perspective. If neither > current or old termios structures have acceptable baud rate setting and > 9600 is not in the min/max range either the function returns 0 and > issues a warning. > However for a UART that does not support speed of 9600 baud this is > expected behavior. > Clarify that 0 can be (and always could be) returned from the > uart_get_baud_rate. Don't issue a warning in that case. > Move the warinng to the uart_get_divisor instead, which is often called > with the uart_get_baud_rate return value. This doesn't match up with the patch contents anymore :(
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 7bdc21d5e13b..3f130fe9f1a0 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -431,7 +431,7 @@ EXPORT_SYMBOL(uart_update_timeout); * baud. * * If the new baud rate is invalid, try the @old termios setting. If it's still - * invalid, we try 9600 baud. + * invalid, we try 9600 baud. If that is also invalid 0 is returned. * * The @termios structure is updated to reflect the baud rate we're actually * going to be using. Don't do this for the case where B0 is requested ("hang @@ -515,8 +515,6 @@ uart_get_baud_rate(struct uart_port *port, struct ktermios *termios, max - 1, max - 1); } } - /* Should never happen */ - WARN_ON(1); return 0; } EXPORT_SYMBOL(uart_get_baud_rate);
uart_get_baud_rate has input parameters 'min' and 'max' limiting the range of acceptable baud rates from the caller's perspective. If neither current or old termios structures have acceptable baud rate setting and 9600 is not in the min/max range either the function returns 0 and issues a warning. However for a UART that does not support speed of 9600 baud this is expected behavior. Clarify that 0 can be (and always could be) returned from the uart_get_baud_rate. Don't issue a warning in that case. Move the warinng to the uart_get_divisor instead, which is often called with the uart_get_baud_rate return value. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> --- Changes v3->v4: - drop WARN_ON from uart_get_divisor() drivers/tty/serial/serial_core.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)