Re: [PATCH] serial: mps2-uart: Add parentheses around conditional in mps2_uart_shutdown
From: Nick Desaulniers <hidden>
Date: 2019-01-31 18:21:20
Also in:
linux-serial, lkml
On Thu, Jan 31, 2019 at 10:06 AM Nathan Chancellor [off-list ref] 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 <redacted> Link: https://github.com/ClangBuiltLinux/linux/issues/344
quoted hunk ↗ jump to hunk
Fixes: 775ea4ea2fd9 ("serial: mps2-uart: support combined irq") Signed-off-by: Nathan Chancellor <redacted> --- 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 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel