[PATCH v2 0/2] Check for endpoints in fwnode->secondary more sensibly

[PATCH v2 0/2] Check for endpoints in fwnode->secondary more sensibly

[Daniel Scally]

Hello all

A while ago I patched fwnode_graph_get_endpoint_by_id() to check for endpoints
against fwnode->secondary if none was found against the primary. It's actually
better to do this in fwnode_graph_get_next_endpoint() instead, since that
function is called by fwnode_graph_get_endpoint_by_id() and also directly called
in a bunch of other places (primarily sensor drivers checking that they have
endpoints connected during probe). This small series just adds the equivalent
functionality to fwnode_graph_get_next_endpoint() and reverts the earlier
commit.

Thanks
Dan

Daniel Scally (2):
  device property: Check fwnode->secondary in
    fwnode_graph_get_next_endpoint()
  Revert "media: device property: Call fwnode_graph_get_endpoint_by_id()
    for fwnode->secondary"

 drivers/base/property.c | 30 +++++++++++++++++++++---------
 1 file changed, 21 insertions(+), 9 deletions(-)

-- 
2.25.1

[PATCH v2 1/2] device property: Check fwnode->secondary in fwnode_graph_get_next_endpoint()

[Daniel Scally]

Sensor drivers often check for an endpoint to make sure that they're
connected to a consuming device like a CIO2 during .probe(). Some of
those endpoints might be in the form of software_nodes assigned as
a secondary to the device's fwnode_handle. Account for this possibility
in fwnode_graph_get_next_endpoint() to avoid having to do it in the
sensor drivers themselves.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Daniel Scally <djrscally@gmail.com>
---
Changes in v2:

	- Re-ordered the IF_ERR_OR_NULL() checks to make the logical flow a bit
	more apparent (Andy)

 drivers/base/property.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/base/property.c b/drivers/base/property.c
index 1421e9548857..fb0e852dad5f 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -1036,7 +1036,26 @@ struct fwnode_handle *
 fwnode_graph_get_next_endpoint(const struct fwnode_handle *fwnode,
 			       struct fwnode_handle *prev)
 {
-	return fwnode_call_ptr_op(fwnode, graph_get_next_endpoint, prev);
+	const struct fwnode_handle *parent;
+	struct fwnode_handle *ep;
+
+	/*
+	 * If this function is in a loop and the previous iteration returned
+	 * an endpoint from fwnode->secondary, then we need to use the secondary
+	 * as parent rather than @fwnode.
+	 */
+	if (prev)
+		parent = fwnode_graph_get_port_parent(prev);
+	else
+		parent = fwnode;
+
+	ep = fwnode_call_ptr_op(parent, graph_get_next_endpoint, prev);
+
+	if (IS_ERR_OR_NULL(ep) &&
+	    !IS_ERR_OR_NULL(parent) && !IS_ERR_OR_NULL(parent->secondary))
+		ep = fwnode_graph_get_next_endpoint(parent->secondary, NULL);
+
+	return ep;
 }
 EXPORT_SYMBOL_GPL(fwnode_graph_get_next_endpoint);
 
-- 
2.25.1

[PATCH v2 2/2] Revert "media: device property: Call fwnode_graph_get_endpoint_by_id() for fwnode->secondary"

[Daniel Scally]

This reverts commit acd418bfcfc415cf5e6414b6d1c6acfec850f290. Checking for
endpoints against fwnode->secondary in fwnode_graph_get_next_endpoint() is
a better way to do this since that function is also used in a bunch of
other places, for instance sensor drivers checking that they do have an
endpoint connected during probe.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Daniel Scally <djrscally@gmail.com>
---
 drivers/base/property.c | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/drivers/base/property.c b/drivers/base/property.c
index fb0e852dad5f..c6bb3d453c57 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -1234,14 +1234,7 @@ fwnode_graph_get_endpoint_by_id(const struct fwnode_handle *fwnode,
 		best_ep_id = fwnode_ep.id;
 	}
 
-	if (best_ep)
-		return best_ep;
-
-	if (fwnode && !IS_ERR_OR_NULL(fwnode->secondary))
-		return fwnode_graph_get_endpoint_by_id(fwnode->secondary, port,
-						       endpoint, flags);
-
-	return NULL;
+	return best_ep;
 }
 EXPORT_SYMBOL_GPL(fwnode_graph_get_endpoint_by_id);
 
-- 
2.25.1

Re: [PATCH v2 2/2] Revert "media: device property: Call fwnode_graph_get_endpoint_by_id() for fwnode->secondary"

[Greg KH]

On Thu, Aug 05, 2021 at 12:03:13AM +0100, Daniel Scally wrote:
> This reverts commit acd418bfcfc415cf5e6414b6d1c6acfec850f290. Checking for
> endpoints against fwnode->secondary in fwnode_graph_get_next_endpoint() is
> a better way to do this since that function is also used in a bunch of
> other places, for instance sensor drivers checking that they do have an
> endpoint connected during probe.
> 
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Signed-off-by: Daniel Scally <djrscally@gmail.com>
> ---
>  drivers/base/property.c | 9 +--------
>  1 file changed, 1 insertion(+), 8 deletions(-)

This can only be reverted due to your 1/2 change, right?  If so, you
might want to make that explicit here...

thanks,

greg k-h

Re: [PATCH v2 2/2] Revert "media: device property: Call fwnode_graph_get_endpoint_by_id() for fwnode->secondary"

[Daniel Scally]

On 05/08/2021 09:38, Greg KH wrote:
> On Thu, Aug 05, 2021 at 12:03:13AM +0100, Daniel Scally wrote:
>> This reverts commit acd418bfcfc415cf5e6414b6d1c6acfec850f290. Checking for
>> endpoints against fwnode->secondary in fwnode_graph_get_next_endpoint() is
>> a better way to do this since that function is also used in a bunch of
>> other places, for instance sensor drivers checking that they do have an
>> endpoint connected during probe.
>>
>> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>> Signed-off-by: Daniel Scally <djrscally@gmail.com>
>> ---
>>  drivers/base/property.c | 9 +--------
>>  1 file changed, 1 insertion(+), 8 deletions(-)
> This can only be reverted due to your 1/2 change, right?


Yes, that's correct.

> If so, you
> might want to make that explicit here...


Fair point - thanks, I'll do that.

>
> thanks,
>
> greg k-h