On Thu, Jan 31, 2019 at 10:06 AM Nathan Chancellor <natechancellor@xxxxxxxxx> wrote: > > Clang warns: > > drivers/tty/serial/mps2-uart.c:351:6: warning: logical not is only > applied to the left hand side of this bitwise operator > [-Wlogical-not-parentheses] > if (!mps_port->flags & UART_PORT_COMBINED_IRQ) { > ^ ~ > drivers/tty/serial/mps2-uart.c:351:6: note: add parentheses after the > '!' to evaluate the bitwise operator first > if (!mps_port->flags & UART_PORT_COMBINED_IRQ) { > ^ > ( ) > drivers/tty/serial/mps2-uart.c:351:6: note: add parentheses around left > hand side expression to silence this warning > if (!mps_port->flags & UART_PORT_COMBINED_IRQ) { > ^ > ( ) > 1 warning generated. > > As it was intended for this check to be the inverse of the one at the > bottom of mps2_init_port, add parentheses around the whole conditional. https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/tty/serial/mps2-uart.c That function currently has the code: if (mps_port->flags & UART_PORT_COMBINED_IRQ) { mps_port->port.irq = platform_get_irq(pdev, 0); } else { mps_port->rx_irq = platform_get_irq(pdev, 0); mps_port->tx_irq = platform_get_irq(pdev, 1); mps_port->port.irq = platform_get_irq(pdev, 2); } while shutdown has: if (!mps_port->flags & UART_PORT_COMBINED_IRQ) { free_irq(mps_port->rx_irq, mps_port); free_irq(mps_port->tx_irq, mps_port); } free_irq(port->irq, mps_port); So port->irq is always assigned an irq, and rx_irq & tx_irq are assigned only if !(mps_port->flags & UART_PORT_COMBINED_IRQ). Yep, patch looks good. Thanks for fixing a real bug here, Nathan. Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Link: https://github.com/ClangBuiltLinux/linux/issues/344 > > Fixes: 775ea4ea2fd9 ("serial: mps2-uart: support combined irq") > Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx> > --- > drivers/tty/serial/mps2-uart.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/tty/serial/mps2-uart.c b/drivers/tty/serial/mps2-uart.c > index 4404eb7d118f..587b42f754cb 100644 > --- a/drivers/tty/serial/mps2-uart.c > +++ b/drivers/tty/serial/mps2-uart.c > @@ -348,7 +348,7 @@ static void mps2_uart_shutdown(struct uart_port *port) > > mps2_uart_write8(port, control, UARTn_CTRL); > > - if (!mps_port->flags & UART_PORT_COMBINED_IRQ) { > + if (!(mps_port->flags & UART_PORT_COMBINED_IRQ)) { > free_irq(mps_port->rx_irq, mps_port); > free_irq(mps_port->tx_irq, mps_port); > } > -- > 2.20.1 > -- Thanks, ~Nick Desaulniers