| Message ID | 20160912133441.14597-1-richard.genoud@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Sep 12, 2016 at 03:34:41PM +0200, Richard Genoud wrote: > Since commit 18dfef9c7f87 ("serial: atmel: convert to irq handling > provided mctrl-gpio"), interrupts from GPIOs are not disabled any more > when the serial port is closed, leading to an oops when the one of the > input pin is toggled (CTS/DSR/DCD/RNG). > > This is only the case if those pins are used as GPIOs, i.e. declared > like that: > usart1: serial@f8020000 { > /* CTS and DTS will be handled by GPIO */ > status = "okay"; > rts-gpios = <&pioB 17 GPIO_ACTIVE_LOW>; > cts-gpios = <&pioB 16 GPIO_ACTIVE_LOW>; > dtr-gpios = <&pioB 14 GPIO_ACTIVE_LOW>; > dsr-gpios = <&pioC 31 GPIO_ACTIVE_LOW>; > rng-gpios = <&pioB 12 GPIO_ACTIVE_LOW>; > dcd-gpios = <&pioB 15 GPIO_ACTIVE_LOW>; > }; > > That's because modem interrupts used to be freed in atmel_shutdown(). > After commit 18dfef9c7f87 ("serial: atmel: convert to irq handling > provided mctrl-gpio"), this code was just removed. > Calling atmel_disable_ms() disables the interrupts and everything works > fine again. > > Tested on at91sam9g35-cm > > (This patch doesn't apply on -stable kernels, fixes for 4.4 and 4.7 will > be sent after this one is applied.) AFAIK this is no reason to not put stable on Cc. If then $stablemaintainer fails to backport the change, he will contact you. > Signed-off-by: Richard Genoud <richard.genoud@gmail.com> > Fixes: 18dfef9c7f87 ("serial: atmel: convert to irq handling provided mctrl-gpio") Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Thanks for caring Uwe
Le 12/09/2016 à 15:34, Richard Genoud a écrit : > Since commit 18dfef9c7f87 ("serial: atmel: convert to irq handling > provided mctrl-gpio"), interrupts from GPIOs are not disabled any more > when the serial port is closed, leading to an oops when the one of the > input pin is toggled (CTS/DSR/DCD/RNG). > > This is only the case if those pins are used as GPIOs, i.e. declared > like that: > usart1: serial@f8020000 { > /* CTS and DTS will be handled by GPIO */ > status = "okay"; > rts-gpios = <&pioB 17 GPIO_ACTIVE_LOW>; > cts-gpios = <&pioB 16 GPIO_ACTIVE_LOW>; > dtr-gpios = <&pioB 14 GPIO_ACTIVE_LOW>; > dsr-gpios = <&pioC 31 GPIO_ACTIVE_LOW>; > rng-gpios = <&pioB 12 GPIO_ACTIVE_LOW>; > dcd-gpios = <&pioB 15 GPIO_ACTIVE_LOW>; > }; > > That's because modem interrupts used to be freed in atmel_shutdown(). > After commit 18dfef9c7f87 ("serial: atmel: convert to irq handling > provided mctrl-gpio"), this code was just removed. > Calling atmel_disable_ms() disables the interrupts and everything works > fine again. > > Tested on at91sam9g35-cm > > (This patch doesn't apply on -stable kernels, fixes for 4.4 and 4.7 will > be sent after this one is applied.) > > Signed-off-by: Richard Genoud <richard.genoud@gmail.com> > Fixes: 18dfef9c7f87 ("serial: atmel: convert to irq handling provided mctrl-gpio") I thinks it's a bit late for "4.8-fixes". Greg, tell me if you want that I add the Cc: stable tag to this patch (as advised by Uwe) and re-send? Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Thanks Richard! Best regards, > --- > drivers/tty/serial/atmel_serial.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c > index 2eaa18ddef61..8bbde52db376 100644 > --- a/drivers/tty/serial/atmel_serial.c > +++ b/drivers/tty/serial/atmel_serial.c > @@ -1929,6 +1929,9 @@ static void atmel_shutdown(struct uart_port *port) > { > struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); > > + /* Disable modem control lines interrupts */ > + atmel_disable_ms(port); > + > /* Disable interrupts at device level */ > atmel_uart_writel(port, ATMEL_US_IDR, -1); > > @@ -1979,8 +1982,6 @@ static void atmel_shutdown(struct uart_port *port) > */ > free_irq(port->irq, port); > > - atmel_port->ms_irq_enabled = false; > - > atmel_flush_buffer(port); > } > >
On Mon, Sep 12, 2016 at 05:22:58PM +0200, Nicolas Ferre wrote: > Le 12/09/2016 à 15:34, Richard Genoud a écrit : > > Since commit 18dfef9c7f87 ("serial: atmel: convert to irq handling > > provided mctrl-gpio"), interrupts from GPIOs are not disabled any more > > when the serial port is closed, leading to an oops when the one of the > > input pin is toggled (CTS/DSR/DCD/RNG). > > > > This is only the case if those pins are used as GPIOs, i.e. declared > > like that: > > usart1: serial@f8020000 { > > /* CTS and DTS will be handled by GPIO */ > > status = "okay"; > > rts-gpios = <&pioB 17 GPIO_ACTIVE_LOW>; > > cts-gpios = <&pioB 16 GPIO_ACTIVE_LOW>; > > dtr-gpios = <&pioB 14 GPIO_ACTIVE_LOW>; > > dsr-gpios = <&pioC 31 GPIO_ACTIVE_LOW>; > > rng-gpios = <&pioB 12 GPIO_ACTIVE_LOW>; > > dcd-gpios = <&pioB 15 GPIO_ACTIVE_LOW>; > > }; > > > > That's because modem interrupts used to be freed in atmel_shutdown(). > > After commit 18dfef9c7f87 ("serial: atmel: convert to irq handling > > provided mctrl-gpio"), this code was just removed. > > Calling atmel_disable_ms() disables the interrupts and everything works > > fine again. > > > > Tested on at91sam9g35-cm > > > > (This patch doesn't apply on -stable kernels, fixes for 4.4 and 4.7 will > > be sent after this one is applied.) > > > > Signed-off-by: Richard Genoud <richard.genoud@gmail.com> > > Fixes: 18dfef9c7f87 ("serial: atmel: convert to irq handling provided mctrl-gpio") > > I thinks it's a bit late for "4.8-fixes". > > Greg, tell me if you want that I add the Cc: stable tag to this patch > (as advised by Uwe) and re-send? I'll add it, no worries. greg k-h
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 2eaa18ddef61..8bbde52db376 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -1929,6 +1929,9 @@ static void atmel_shutdown(struct uart_port *port) { struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + /* Disable modem control lines interrupts */ + atmel_disable_ms(port); + /* Disable interrupts at device level */ atmel_uart_writel(port, ATMEL_US_IDR, -1); @@ -1979,8 +1982,6 @@ static void atmel_shutdown(struct uart_port *port) */ free_irq(port->irq, port); - atmel_port->ms_irq_enabled = false; - atmel_flush_buffer(port); }
Since commit 18dfef9c7f87 ("serial: atmel: convert to irq handling provided mctrl-gpio"), interrupts from GPIOs are not disabled any more when the serial port is closed, leading to an oops when the one of the input pin is toggled (CTS/DSR/DCD/RNG). This is only the case if those pins are used as GPIOs, i.e. declared like that: usart1: serial@f8020000 { /* CTS and DTS will be handled by GPIO */ status = "okay"; rts-gpios = <&pioB 17 GPIO_ACTIVE_LOW>; cts-gpios = <&pioB 16 GPIO_ACTIVE_LOW>; dtr-gpios = <&pioB 14 GPIO_ACTIVE_LOW>; dsr-gpios = <&pioC 31 GPIO_ACTIVE_LOW>; rng-gpios = <&pioB 12 GPIO_ACTIVE_LOW>; dcd-gpios = <&pioB 15 GPIO_ACTIVE_LOW>; }; That's because modem interrupts used to be freed in atmel_shutdown(). After commit 18dfef9c7f87 ("serial: atmel: convert to irq handling provided mctrl-gpio"), this code was just removed. Calling atmel_disable_ms() disables the interrupts and everything works fine again. Tested on at91sam9g35-cm (This patch doesn't apply on -stable kernels, fixes for 4.4 and 4.7 will be sent after this one is applied.) Signed-off-by: Richard Genoud <richard.genoud@gmail.com> Fixes: 18dfef9c7f87 ("serial: atmel: convert to irq handling provided mctrl-gpio") --- drivers/tty/serial/atmel_serial.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)