Re: [PATCH v2 2/7] driver: Add rescan hook to struct device

[Sascha Hauer <s.hauer@pengutronix.de>]

On Thu, Mar 09, 2023 at 04:41:05PM +0100, Sascha Hauer wrote:
> On Thu, Mar 09, 2023 at 02:08:50PM +0100, Ahmad Fatoum wrote:
> > On 09.03.23 12:52, Sascha Hauer wrote:
> > > When devices are enabled with a device tree overlay the newly enabled
> > > devices can be probed by doing a of_probe(). This works fine for the
> > > regular platform devices, but doesn't work for devices which are not
> > > probed by the core, but by the subsystem. Prominent examples are I2C or
> > > SPI devices.
> > > 
> > > This patch adds a struct device::rescan hook that subsystems can
> > > implement to trigger rescanning the device nodes.
> > > 
> > > Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> > > ---
> > >  drivers/of/platform.c | 11 +++++------
> > >  include/driver.h      |  6 ++++++
> > >  2 files changed, 11 insertions(+), 6 deletions(-)
> > > 
> > > diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> > > index edb082b106..2e9abe32bc 100644
> > > --- a/drivers/of/platform.c
> > > +++ b/drivers/of/platform.c
> > > @@ -153,8 +153,10 @@ struct device *of_platform_device_create(struct device_node *np,
> > >  	 * Linux uses the OF_POPULATED flag to skip already populated/created
> > >  	 * devices.
> > >  	 */
> > > -	if (np->dev)
> > > +	if (np->dev) {
> > > +		device_rescan(np->dev);
> > >  		return np->dev;
> > > +	}
> > >  
> > >  	/* count the io resources */
> > >  	if (of_can_translate_address(np))
> > > @@ -420,11 +422,8 @@ static struct device *of_device_create_on_demand(struct device_node *np)
> > >  	if (!parent)
> > >  		return NULL;
> > >  
> > > -	if (!np->dev && parent->dev) {
> > > -		ret = device_detect(parent->dev);
> > > -		if (ret && ret != -ENOSYS)
> > > -			return ERR_PTR(ret);
> > > -	}
> > 
> > The int ret definition at the top of the function should be ok to be removed now.
> 
> No, it's still used.

Hm, looked at the wrong function it seems. Compiler says it's unused.

Sascha

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