Re: [PATCH] of/platform: Support dynamic device tree on AMBA bus

[Jaewon Kim]

Hi Frank,


Thanks to review my patch.

On 18. 10. 31. ìì 8:04, Frank Rowand wrote:
> Hi Jaewon,
>
> On 10/25/18 9:39 AM, Jaewon Kim wrote:
> > This patch supports dynamic device-tree for AMBA device.
> Add AMBA devices and buses to of_platform_notify() so that dynamic device-tree
> will support AMBA.

What is meaning of this comment?

I already adds AMBA to of_platform_notify().

> > The AMBA device must be registered on the AMBA bus, not the platform bus.
> >
> > Signed-off-by: Jaewon Kim <jaewon02.kim@xxxxxxxxxxx>
> > ---
> >   drivers/of/platform.c | 93 ++++++++++++++++++++++++++++++++++++++++-----------
> >   1 file changed, 73 insertions(+), 20 deletions(-)
> >
> > diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> > index 04ad312..b9ac105 100644
> > --- a/drivers/of/platform.c
> > +++ b/drivers/of/platform.c
> > @@ -286,6 +286,22 @@ static struct amba_device *of_amba_device_create(struct device_node *node,
> >   	of_node_clear_flag(node, OF_POPULATED);
> >   	return NULL;
> >   }
> > +
> > +/**
> > + * of_find_amba_device_by_node - Find the amba_device associated with a node
> > + * @np: Pointer to device tree node
> > + *
> > + * Returns amba_device pointer, or NULL if not found
> > + */
> > +struct amba_device *of_find_amba_device_by_node(struct device_node *np)
> > +{
> > +	struct device *dev;
> > +
> > +	dev = bus_find_device(&amba_bustype, NULL, np, of_dev_node_match);
> > +	return dev ? to_amba_device(dev) : NULL;
> > +}
> > +EXPORT_SYMBOL(of_find_amba_device_by_node);
> > +
> >   #else /* CONFIG_ARM_AMBA */
> >   static struct amba_device *of_amba_device_create(struct device_node *node,
> >   						 const char *bus_id,
> > @@ -294,6 +310,12 @@ static struct amba_device *of_amba_device_create(struct device_node *node,
> >   {
> >   	return NULL;
> >   }
> > +
> > +struct amba_device *of_find_amba_device_by_node(struct device_node *np)
> > +{
> > +	return NULL;
> > +}
> > +EXPORT_SYMBOL(of_find_amba_device_by_node);
> >   #endif /* CONFIG_ARM_AMBA */
> >   
> >   /**
> > @@ -665,6 +687,7 @@ static int of_platform_notify(struct notifier_block *nb,
> >   {
> >   	struct of_reconfig_data *rd = arg;
> >   	struct platform_device *pdev_parent, *pdev;
> > +	struct amba_device *adev_p, *adev;
> >   	bool children_left;
> >   
> >   	switch (of_reconfig_get_state_change(action, rd)) {
> > @@ -677,17 +700,34 @@ static int of_platform_notify(struct notifier_block *nb,
> >   		if (of_node_check_flag(rd->dn, OF_POPULATED))
> >   			return NOTIFY_OK;
> >   
> > -		/* pdev_parent may be NULL when no bus platform device */
> > -		pdev_parent = of_find_device_by_node(rd->dn->parent);
> > -		pdev = of_platform_device_create(rd->dn, NULL,
> > -				pdev_parent ? &pdev_parent->dev : NULL);
> > -		of_dev_put(pdev_parent);
> > -
> > -		if (pdev == NULL) {
> > -			pr_err("%s: failed to create for '%pOF'\n",
> > -					__func__, rd->dn);
> > -			/* of_platform_device_create tosses the error code */
> > -			return notifier_from_errno(-EINVAL);
> > +		if (of_device_is_compatible(rd->dn, "arm,primecell")) {
> > +			/* adev_p may be NULL when no bus amba device */
> > +			adev_p = of_find_amba_device_by_node(rd->dn->parent);
> > +			adev = of_amba_device_create(rd->dn, NULL, NULL,
> > +					adev_p ? &adev_p->dev : NULL);
> > +
> > +			if (adev_p)
> > +				put_device(&adev_p->dev);
> Please follow the same model as of_dev_put() here, create a new function
> of_amba_dev_put() to implement these two lines.
Okay, I will create of_amba_dev_put() function.
> > +
> > +			if (adev == NULL) {
> > +				pr_err("%s: failed to create for '%s'\n",
> > +						__func__, rd->dn->full_name);
> > +				/* of_amba_device_create tosses the error */
> > +				return notifier_from_errno(-EINVAL);
> > +			}
> > +		} else {
> > +			/* pdev_parent may be NULL when no bus platform device*/
> > +			pdev_parent = of_find_device_by_node(rd->dn->parent);
> > +			pdev = of_platform_device_create(rd->dn, NULL,
> > +					pdev_parent ? &pdev_parent->dev : NULL);
> > +			of_dev_put(pdev_parent);
> > +
> > +			if (pdev == NULL) {
> > +				pr_err("%s: failed to create for '%pOF'\n",
> > +						__func__, rd->dn);
> > +				/* of_platform_device_create tosses the error */
> > +				return notifier_from_errno(-EINVAL);
> > +			}
> >   		}
> >   		break;
> >   
> > @@ -698,15 +738,28 @@ static int of_platform_notify(struct notifier_block *nb,
> >   			return NOTIFY_OK;
> >   
> >   		/* find our device by node */
> > -		pdev = of_find_device_by_node(rd->dn);
> > -		if (pdev == NULL)
> > -			return NOTIFY_OK;	/* no? not meant for us */
> > -
> > -		/* unregister takes one ref away */
> > -		of_platform_device_destroy(&pdev->dev, &children_left);
> > -
> > -		/* and put the reference of the find */
> > -		of_dev_put(pdev);
> > +		if (of_device_is_compatible(rd->dn, "arm,primecell")) {
> > +			adev = of_find_amba_device_by_node(rd->dn);
> > +			if (adev == NULL)
> > +				return NOTIFY_OK; /* no? not meant for us */
> > +
> > +			/* unregister takes one ref away */
> > +			of_platform_device_destroy(&adev->dev, &children_left);
> > +
> > +			/* and put the reference of the find */
> > +			if (adev)
> > +				put_device(&adev->dev);
> of_amba_dev_put() here also
>
> -Frank
Okay, I will create it.
> > +		} else {
> > +			pdev = of_find_device_by_node(rd->dn);
> > +			if (pdev == NULL)
> > +				return NOTIFY_OK; /* no? not meant for us */
> > +
> > +			/* unregister takes one ref away */
> > +			of_platform_device_destroy(&pdev->dev, &children_left);
> > +
> > +			/* and put the reference of the find */
> > +			of_dev_put(pdev);
> > +		}
> >   		break;
> >   	}
> >   
Thanks

Jaewon Kim