On Wed, Aug 10, 2016 at 09:00:15AM +0000, Jun Li wrote:

Hi, Peter

quoted

-----Original Message-----
From: linux-usb-owner at vger.kernel.org [mailto:linux-usb-
owner at vger.kernel.org] On Behalf Of Peter Chen
Sent: Wednesday, August 10, 2016 11:12 AM
To: Stephen Boyd <redacted>
Cc: Peter Chen <redacted>; gregkh at linuxfoundation.org;
stern at rowland.harvard.edu; ulf.hansson at linaro.org; broonie at kernel.org;
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Peter Chen [off-list ref]
Subject: Re: [PATCH v5 5/6] usb: chipidea: let chipidea core device
of_node equal's glue layer device of_node

On Tue, Aug 09, 2016 at 05:15:36PM -0700, Stephen Boyd wrote:

quoted

Quoting Peter Chen (2016-08-08 01:52:10)

quoted

From: Peter Chen <redacted>

At device tree, we have no device node for chipidea core, the glue
layer's node is the parent node for host and udc device. But in
related driver, the parent device is chipidea core. So, in order to
let the common driver get parent's node, we let the core's device
node equals glue layer device node.

Signed-off-by: Peter Chen <redacted>
Tested-by: Maciej S. Szmigiero <redacted>
Tested-by Joshua Clayton [off-list ref]
---
 drivers/usb/chipidea/core.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/usb/chipidea/core.c

b/drivers/usb/chipidea/core.c index 69426e6..b189dc7 100644

--- a/drivers/usb/chipidea/core.c
+++ b/drivers/usb/chipidea/core.c

@@ -954,6 +954,15 @@ static int ci_hdrc_probe(struct platform_device

*pdev)

quoted

quoted

                dev_err(dev, "unable to init phy: %d\n", ret);
                return ret;
        }
+       /*
+        * At device tree, we have no device node for chipidea core,
+        * the glue layer's node is the parent node for host and udc
+        * device. But in related driver, the parent device is

chipidea

quoted

quoted

+        * core. So, in order to let the common driver get parent's

node,

quoted

quoted

+        * we let the core's device node equals glue layer's node.
+        */
+       if (dev->parent && dev->parent->of_node)
+               dev->of_node = dev->parent->of_node;

Can this be done earlier? Perhaps after hw_device_init() in this probe
routine? That would allow me to remove the awkward parent searching in
my ULPI DT awareness patch.

The reason why I locate it there is to avoid "goto label" for error path
during PHY's get and initialization operation.

Ok, to simplify your work, I will change it at next version.

As iommu need this to be done even more earlier, will you consider to
put it before adding the core's platform device?

I can't do it, it will introduce another issue that the pinctrl has
already requested by parents. The warning is similar like below, but
occurs at the probe.

http://lkml.iu.edu/hypermail/linux/kernel/1607.2/03150.html

I will see how iommu support can be added for platform devices which
are created by runtime (like chipidea core device).

-- 

Best Regards,
Peter Chen