Re: [PATCH v4 2/9] serdev: Add an API to find the serdev controller associated with the devicetree node

[Manivannan Sadhasivam]

On Tue, Jan 13, 2026 at 08:54:55AM -0500, Bartosz Golaszewski wrote:
> On Mon, 12 Jan 2026 17:26:01 +0100, Manivannan Sadhasivam via B4 Relay
> <devnull+manivannan.sadhasivam.oss.qualcomm.com@xxxxxxxxxx> said:
> > From: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxxxxxxxx>
> >
> > Add of_find_serdev_controller_by_node() API to find the serdev controller
> > device associated with the devicetree node.
> >
> > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxxxxxxxx>
> > ---
> >  drivers/tty/serdev/core.c | 16 ++++++++++++++++
> >  include/linux/serdev.h    |  9 +++++++++
> >  2 files changed, 25 insertions(+)
> >
> > diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
> > index b33e708cb245..25382c2d63e6 100644
> > --- a/drivers/tty/serdev/core.c
> > +++ b/drivers/tty/serdev/core.c
> > @@ -504,6 +504,22 @@ struct serdev_controller *serdev_controller_alloc(struct device *host,
> >  }
> >  EXPORT_SYMBOL_GPL(serdev_controller_alloc);
> >
> > +/**
> > + * of_find_serdev_controller_by_node() - Find the serdev controller associated
> > + *					 with the devicetree node
> > + * @node:	Devicetree node
> > + *
> > + * Return: Pointer to the serdev controller associated with the node. NULL if
> > + * the controller is not found.
> > + */
> 
> Please also say that the caller is responsible for calling
> serdev_controller_put() on the returned object.
> 

Ack.

- Mani

> Bart
> 
> > +struct serdev_controller *of_find_serdev_controller_by_node(struct device_node *node)
> > +{
> > +	struct device *dev = bus_find_device_by_of_node(&serdev_bus_type, node);
> > +
> > +	return (dev && dev->type == &serdev_ctrl_type) ? to_serdev_controller(dev) : NULL;
> > +}
> > +EXPORT_SYMBOL_GPL(of_find_serdev_controller_by_node);
> > +
> >  static int of_serdev_register_devices(struct serdev_controller *ctrl)
> >  {
> >  	struct device_node *node;
> > diff --git a/include/linux/serdev.h b/include/linux/serdev.h
> > index ecde0ad3e248..db9bfaba0662 100644
> > --- a/include/linux/serdev.h
> > +++ b/include/linux/serdev.h
> > @@ -333,4 +333,13 @@ static inline bool serdev_acpi_get_uart_resource(struct acpi_resource *ares,
> >  }
> >  #endif /* CONFIG_ACPI */
> >
> > +#ifdef CONFIG_OF
> > +struct serdev_controller *of_find_serdev_controller_by_node(struct device_node *node);
> > +#else
> > +struct serdev_controller *of_find_serdev_controller_by_node(struct device_node *node)
> > +{
> > +	return NULL;
> > +}
> > +#endif /* CONFIG_OF */
> > +
> >  #endif /*_LINUX_SERDEV_H */
> >
> > --
> > 2.48.1
> >
> >
> >

-- 
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