| Message ID | 1413353967-27866-1-git-send-email-jingchang.lu@freescale.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 10/15/2014 02:19 PM, Jingchang Lu wrote: > This patch fixes commit 2dea53bf57783f243c892e99c10c6921e956aa7e, > "serial: of-serial: add PM suspend/resume support", which disables > the uart clock on suspend, but also causes a hardware hang on register > access if no_console_suspend command line option is used. > > Also, not every of_serial device is an 8250 port, so the serial8250 > suspend/resume functions should only be applied to a real 8250 port. > > Signed-off-by: Jingchang Lu <jingchang.lu@freescale.com> > --- > changes in v5: > add missing <linux/console.h> include. > > changes in v4: > separate 8250 port suspend/resume from of_serial_suspend/resume. > > changes in v3: > fix up point reference and deference. > > changes in v2: > add switch selection on uart type. > Hi Jingchang, Thanks for the fix. This patch Tested-by: Joseph Lo <josephl@nvidia.com> > drivers/tty/serial/of_serial.c | 53 ++++++++++++++++++++++++++++++++++++------ > 1 file changed, 46 insertions(+), 7 deletions(-) > > diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c > index 8bc2563..9c64ad2 100644 > --- a/drivers/tty/serial/of_serial.c > +++ b/drivers/tty/serial/of_serial.c > @@ -9,6 +9,7 @@ > * 2 of the License, or (at your option) any later version. > * > */ > +#include <linux/console.h> > #include <linux/module.h> > #include <linux/slab.h> > #include <linux/delay.h> > @@ -241,13 +242,48 @@ static int of_platform_serial_remove(struct platform_device *ofdev) > } > > #ifdef CONFIG_PM_SLEEP > -static int of_serial_suspend(struct device *dev) > +#ifdef CONFIG_SERIAL_8250 > +static void of_serial_suspend_8250(struct of_serial_info *info) > { > - struct of_serial_info *info = dev_get_drvdata(dev); > + struct uart_8250_port *port8250 = serial8250_get_port(info->line); > + struct uart_port *port = &port8250->port; > > serial8250_suspend_port(info->line); > - if (info->clk) > + if (info->clk && (!uart_console(port) || console_suspend_enabled)) > clk_disable_unprepare(info->clk); > +} > + > +static void of_serial_resume_8250(struct of_serial_info *info) > +{ > + struct uart_8250_port *port8250 = serial8250_get_port(info->line); > + struct uart_port *port = &port8250->port; > + > + if (info->clk && (!uart_console(port) || console_suspend_enabled)) > + clk_prepare_enable(info->clk); > + > + serial8250_resume_port(info->line); > +} > +#else > +static inline void of_serial_suspend_8250(struct of_serial_info *info) > +{ > +} > + > +static inline void of_serial_resume_8250(struct of_serial_info *info) > +{ > +} > +#endif > + > +static int of_serial_suspend(struct device *dev) > +{ > + struct of_serial_info *info = dev_get_drvdata(dev); > + > + switch(info->type) { > + case PORT_8250 ... PORT_MAX_8250: > + of_serial_suspend_8250(info); > + break; > + default: > + break; > + } > > return 0; > } > @@ -256,10 +292,13 @@ static int of_serial_resume(struct device *dev) > { > struct of_serial_info *info = dev_get_drvdata(dev); > > - if (info->clk) > - clk_prepare_enable(info->clk); > - > - serial8250_resume_port(info->line); > + switch(info->type) { > + case PORT_8250 ... PORT_MAX_8250: > + of_serial_resume_8250(info); > + break; > + default: > + break; > + } > > return 0; > } >
diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c index 8bc2563..9c64ad2 100644 --- a/drivers/tty/serial/of_serial.c +++ b/drivers/tty/serial/of_serial.c @@ -9,6 +9,7 @@ * 2 of the License, or (at your option) any later version. * */ +#include <linux/console.h> #include <linux/module.h> #include <linux/slab.h> #include <linux/delay.h> @@ -241,13 +242,48 @@ static int of_platform_serial_remove(struct platform_device *ofdev) } #ifdef CONFIG_PM_SLEEP -static int of_serial_suspend(struct device *dev) +#ifdef CONFIG_SERIAL_8250 +static void of_serial_suspend_8250(struct of_serial_info *info) { - struct of_serial_info *info = dev_get_drvdata(dev); + struct uart_8250_port *port8250 = serial8250_get_port(info->line); + struct uart_port *port = &port8250->port; serial8250_suspend_port(info->line); - if (info->clk) + if (info->clk && (!uart_console(port) || console_suspend_enabled)) clk_disable_unprepare(info->clk); +} + +static void of_serial_resume_8250(struct of_serial_info *info) +{ + struct uart_8250_port *port8250 = serial8250_get_port(info->line); + struct uart_port *port = &port8250->port; + + if (info->clk && (!uart_console(port) || console_suspend_enabled)) + clk_prepare_enable(info->clk); + + serial8250_resume_port(info->line); +} +#else +static inline void of_serial_suspend_8250(struct of_serial_info *info) +{ +} + +static inline void of_serial_resume_8250(struct of_serial_info *info) +{ +} +#endif + +static int of_serial_suspend(struct device *dev) +{ + struct of_serial_info *info = dev_get_drvdata(dev); + + switch(info->type) { + case PORT_8250 ... PORT_MAX_8250: + of_serial_suspend_8250(info); + break; + default: + break; + } return 0; } @@ -256,10 +292,13 @@ static int of_serial_resume(struct device *dev) { struct of_serial_info *info = dev_get_drvdata(dev); - if (info->clk) - clk_prepare_enable(info->clk); - - serial8250_resume_port(info->line); + switch(info->type) { + case PORT_8250 ... PORT_MAX_8250: + of_serial_resume_8250(info); + break; + default: + break; + } return 0; }
This patch fixes commit 2dea53bf57783f243c892e99c10c6921e956aa7e, "serial: of-serial: add PM suspend/resume support", which disables the uart clock on suspend, but also causes a hardware hang on register access if no_console_suspend command line option is used. Also, not every of_serial device is an 8250 port, so the serial8250 suspend/resume functions should only be applied to a real 8250 port. Signed-off-by: Jingchang Lu <jingchang.lu@freescale.com> --- changes in v5: add missing <linux/console.h> include. changes in v4: separate 8250 port suspend/resume from of_serial_suspend/resume. changes in v3: fix up point reference and deference. changes in v2: add switch selection on uart type. drivers/tty/serial/of_serial.c | 53 ++++++++++++++++++++++++++++++++++++------ 1 file changed, 46 insertions(+), 7 deletions(-)