| Message ID | 20200506072314.112409-2-tientzu@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | add wakeup_irq for in-band wakeup support | expand |
On Wed, May 06, 2020 at 03:23:12PM +0800, Claire Chang wrote: > serial_match_port() uses devt to match devices. However, when serdev > registers a tty port, devt has never been set. This makes > device_find_child() always return NULL. > > Assign devt in serdev_tty_port_register() to fix this. > > Signed-off-by: Claire Chang <tientzu@chromium.org> > --- > drivers/tty/serdev/serdev-ttyport.c | 2 ++ > 1 file changed, 2 insertions(+) So is existing code broken because of this? Or does no one ever call device_find_child() on this? Who needs/uses this? thanks, greg k-h
On Fri, May 15, 2020 at 8:46 PM Greg KH <gregkh@linuxfoundation.org> wrote: > > On Wed, May 06, 2020 at 03:23:12PM +0800, Claire Chang wrote: > > serial_match_port() uses devt to match devices. However, when serdev > > registers a tty port, devt has never been set. This makes > > device_find_child() always return NULL. > > > > Assign devt in serdev_tty_port_register() to fix this. > > > > Signed-off-by: Claire Chang <tientzu@chromium.org> > > --- > > drivers/tty/serdev/serdev-ttyport.c | 2 ++ > > 1 file changed, 2 insertions(+) > > So is existing code broken because of this? Or does no one ever call > device_find_child() on this? Who needs/uses this? > > thanks, > > greg k-h I'm not sure. Our use case is to control the wake on bluetooth behavior by the power/wakeup node. `readlink -f /sys/class/bluetooth/hci0` /sys/devices/platform/soc/11003000.serial/serial0/serial0-0/bluetooth/hci0 and we'd like to use `/sys/devices/platform/soc/11003000.serial/serial0/power/wakeup` to decide whether to enable the in-band wakeup on uart host side. Thanks, Claire
On Wed, May 06, 2020 at 03:23:12PM +0800, Claire Chang wrote: > serial_match_port() uses devt to match devices. However, when serdev > registers a tty port, devt has never been set. This makes > device_find_child() always return NULL. > > Assign devt in serdev_tty_port_register() to fix this. > > Signed-off-by: Claire Chang <tientzu@chromium.org> > --- > drivers/tty/serdev/serdev-ttyport.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/tty/serdev/serdev-ttyport.c b/drivers/tty/serdev/serdev-ttyport.c > index d367803e2044f..9238119173a47 100644 > --- a/drivers/tty/serdev/serdev-ttyport.c > +++ b/drivers/tty/serdev/serdev-ttyport.c > @@ -267,6 +267,7 @@ struct device *serdev_tty_port_register(struct tty_port *port, > { > struct serdev_controller *ctrl; > struct serport *serport; > + dev_t devt = MKDEV(drv->major, drv->minor_start) + idx; > int ret; > > if (!port || !drv || !parent) > @@ -282,6 +283,7 @@ struct device *serdev_tty_port_register(struct tty_port *port, > serport->tty_drv = drv; > > ctrl->ops = &ctrl_ops; > + ctrl->dev.devt = devt; This is conceptually wrong. A serdev controller is not a tty class device with a corresponding character device. It seems you need to rethink how serial core should handle the wakeup flags with respect to serdev. > > port->client_ops = &client_ops; > port->client_data = ctrl; Johan
diff --git a/drivers/tty/serdev/serdev-ttyport.c b/drivers/tty/serdev/serdev-ttyport.c index d367803e2044f..9238119173a47 100644 --- a/drivers/tty/serdev/serdev-ttyport.c +++ b/drivers/tty/serdev/serdev-ttyport.c @@ -267,6 +267,7 @@ struct device *serdev_tty_port_register(struct tty_port *port, { struct serdev_controller *ctrl; struct serport *serport; + dev_t devt = MKDEV(drv->major, drv->minor_start) + idx; int ret; if (!port || !drv || !parent) @@ -282,6 +283,7 @@ struct device *serdev_tty_port_register(struct tty_port *port, serport->tty_drv = drv; ctrl->ops = &ctrl_ops; + ctrl->dev.devt = devt; port->client_ops = &client_ops; port->client_data = ctrl;
serial_match_port() uses devt to match devices. However, when serdev registers a tty port, devt has never been set. This makes device_find_child() always return NULL. Assign devt in serdev_tty_port_register() to fix this. Signed-off-by: Claire Chang <tientzu@chromium.org> --- drivers/tty/serdev/serdev-ttyport.c | 2 ++ 1 file changed, 2 insertions(+)