On Sat, Aug 13, 2016 at 05:14:33AM +0200, Sebastian Reichel wrote: > From: NeilBrown <neilb@xxxxxxx> > > A "tty slave" is a device connected via UART. It may need a driver to, > for example, power the device on when the tty is opened, and power it > off when the tty is released. > > Signed-off-by: NeilBrown <neilb@xxxxxxx> > Signed-off-by: Sebastian Reichel <sre@xxxxxxxxxx> > --- > Documentation/devicetree/bindings/serial/8250.txt | 4 ++++ > drivers/tty/tty_io.c | 6 ++++++ > 2 files changed, 10 insertions(+) > > diff --git a/Documentation/devicetree/bindings/serial/8250.txt b/Documentation/devicetree/bindings/serial/8250.txt > index f5561ac7e17e..ecb74730f71b 100644 > --- a/Documentation/devicetree/bindings/serial/8250.txt > +++ b/Documentation/devicetree/bindings/serial/8250.txt > @@ -46,6 +46,10 @@ Optional properties: > line respectively. It will use specified GPIO instead of the peripheral > function pin for the UART feature. If unsure, don't specify this property. > > +Optional child node: > +- a device connected to the uart can be specified as child node with > + compatible value. > + > Note: > * fsl,ns16550: > ------------ > diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c > index 734a635e7363..39ff5dcdfd50 100644 > --- a/drivers/tty/tty_io.c > +++ b/drivers/tty/tty_io.c > @@ -95,6 +95,7 @@ > #include <linux/seq_file.h> > #include <linux/serial.h> > #include <linux/ratelimit.h> > +#include <linux/of_platform.h> > > #include <linux/uaccess.h> > > @@ -3317,6 +3318,11 @@ struct device *tty_register_device_attr(struct tty_driver *driver, > retval = device_register(dev); > if (retval) > goto error; > + if (device && device->of_node) > + /* Children are platform devices and will be > + * runtime_pm managed by this tty. > + */ > + of_platform_populate(device->of_node, NULL, NULL, dev); Why are these platform devices? And why only OF? thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
