| Message ID | 7bfab9fb4313e64d8998a78e49411bdc7f9bd7c7.1712303358.git.esben@geanix.com |
|---|---|
| State | New |
| Headers | show |
| Series | serial: imx: Switch to nbcon console | expand |
On 05.04.2024 09:56:37, Esben Haabendal wrote: > By waiting at most 1 second for USR2_TXDC to be set, we avoid a potentital > deadlock. > > In case of the timeout, there is not much we can do, so we simply ignore > the transmitter state and optimistically try to continue. > > Signed-off-by: Esben Haabendal <esben@geanix.com> For the next round you should consult "scripts/get_maintainer.pl drivers/tty/serial/imx.c" and add these people/lists on Cc. > --- > drivers/tty/serial/imx.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c > index 54b760d845c0..f7e4f38f08f3 100644 > --- a/drivers/tty/serial/imx.c > +++ b/drivers/tty/serial/imx.c > @@ -26,6 +26,7 @@ > #include <linux/slab.h> > #include <linux/of.h> > #include <linux/io.h> > +#include <linux/iopoll.h> > #include <linux/dma-mapping.h> > > #include <asm/irq.h> > @@ -1995,7 +1996,7 @@ imx_uart_console_write(struct console *co, const char *s, unsigned int count) > struct imx_port *sport = imx_uart_ports[co->index]; > struct imx_port_ucrs old_ucr; > unsigned long flags; > - unsigned int ucr1; > + unsigned int ucr1, usr2; > int locked = 1; > > if (sport->port.sysrq) > @@ -2026,8 +2027,8 @@ imx_uart_console_write(struct console *co, const char *s, unsigned int count) > * Finally, wait for transmitter to become empty > * and restore UCR1/2/3 > */ > - while (!(imx_uart_readl(sport, USR2) & USR2_TXDC)); > - > + read_poll_timeout_atomic(imx_uart_readl, usr2, usr2 & USR2_TXDC, > + 0, 1000000, false, sport, USR2); You can make use of USEC_PER_SEC here. After fixing this, feel free to add my: Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> > imx_uart_ucrs_restore(sport, &old_ucr); > > if (locked) > -- > 2.44.0 > > Marc
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 54b760d845c0..f7e4f38f08f3 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -26,6 +26,7 @@ #include <linux/slab.h> #include <linux/of.h> #include <linux/io.h> +#include <linux/iopoll.h> #include <linux/dma-mapping.h> #include <asm/irq.h> @@ -1995,7 +1996,7 @@ imx_uart_console_write(struct console *co, const char *s, unsigned int count) struct imx_port *sport = imx_uart_ports[co->index]; struct imx_port_ucrs old_ucr; unsigned long flags; - unsigned int ucr1; + unsigned int ucr1, usr2; int locked = 1; if (sport->port.sysrq) @@ -2026,8 +2027,8 @@ imx_uart_console_write(struct console *co, const char *s, unsigned int count) * Finally, wait for transmitter to become empty * and restore UCR1/2/3 */ - while (!(imx_uart_readl(sport, USR2) & USR2_TXDC)); - + read_poll_timeout_atomic(imx_uart_readl, usr2, usr2 & USR2_TXDC, + 0, 1000000, false, sport, USR2); imx_uart_ucrs_restore(sport, &old_ucr); if (locked)
By waiting at most 1 second for USR2_TXDC to be set, we avoid a potentital deadlock. In case of the timeout, there is not much we can do, so we simply ignore the transmitter state and optimistically try to continue. Signed-off-by: Esben Haabendal <esben@geanix.com> --- drivers/tty/serial/imx.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)