[RFC] usb: chipidea: set dma_ops for the created ci_hdrc platform_device

[RFC] usb: chipidea: set dma_ops for the created ci_hdrc platform_device

[Jisheng Zhang]

Hi all,

After commit 1dccb598df549 ("arm64: simplify dma_get_ops"), the chipidea
driver can't work any more on Marvell Berlin arm64 platforms, the reason
is the created ci_hdrc platform_device's dma_ops is dummy_dma_ops, so all
dma related operations will fail. The fix I can think of would be something
as below:

And I noticed that dwc3 has the same issue[1], and as pointed out in its
discussion, the patch can't fix None-DT platforms, so could you please
guide me what's the proper fix which can be mainlined?

Any suggestion is appreciated!

Thanks,
Jisheng

[1] http://lists.infradead.org/pipermail/linux-arm-kernel/2016-April/425079.html

diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
index 047afdbb7049..acb80457603c 100644
--- a/drivers/usb/chipidea/core.c
+++ b/drivers/usb/chipidea/core.c
@@ -62,6 +62,7 @@
 #include <linux/usb/chipidea.h>
 #include <linux/usb/of.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/regulator/consumer.h>
 #include <linux/usb/ehci_def.h>
 
@@ -786,6 +787,7 @@ struct platform_device *ci_hdrc_add_device(struct device *dev,
 	pdev->dev.dma_mask = dev->dma_mask;
 	pdev->dev.dma_parms = dev->dma_parms;
 	dma_set_coherent_mask(&pdev->dev, dev->coherent_dma_mask);
+	of_dma_configure(&pdev->dev, dev->of_node);
 
 	ret = platform_device_add_resources(pdev, res, nres);
 	if (ret)

[RFC] usb: chipidea: set dma_ops for the created ci_hdrc platform_device

[Arnd Bergmann]

On Tue, Apr 25, 2017 at 12:01 PM, Jisheng Zhang <jszhang@marvell.com> wrote:
> Hi all,
>
> After commit 1dccb598df549 ("arm64: simplify dma_get_ops"), the chipidea
> driver can't work any more on Marvell Berlin arm64 platforms, the reason
> is the created ci_hdrc platform_device's dma_ops is dummy_dma_ops, so all
> dma related operations will fail. The fix I can think of would be something
> as below:
>
> And I noticed that dwc3 has the same issue[1], and as pointed out in its
> discussion, the patch can't fix None-DT platforms, so could you please
> guide me what's the proper fix which can be mainlined?

I think the right solution is:

- Set the "sysdev" pointer tin the USB device o the device structure that
  was created by DT or the legacy board file and remove the manual
  setting of dma_mask,  parms and the dma_configure. This should
  make everything work as expected in case of DT

- For any legacy board files, set the mask/parms and map_ops at
  the point where the device originally created.

      Arnd

[RFC] usb: chipidea: set dma_ops for the created ci_hdrc platform_device

[Jisheng Zhang]

On Tue, 25 Apr 2017 13:09:27 +0200 Arnd Bergmann wrote:

> On Tue, Apr 25, 2017 at 12:01 PM, Jisheng Zhang <jszhang@marvell.com> wrote:
> > Hi all,
> >
> > After commit 1dccb598df549 ("arm64: simplify dma_get_ops"), the chipidea
> > driver can't work any more on Marvell Berlin arm64 platforms, the reason
> > is the created ci_hdrc platform_device's dma_ops is dummy_dma_ops, so all
> > dma related operations will fail. The fix I can think of would be something
> > as below:
> >
> > And I noticed that dwc3 has the same issue[1], and as pointed out in its
> > discussion, the patch can't fix None-DT platforms, so could you please
> > guide me what's the proper fix which can be mainlined?  
> 
> I think the right solution is:
> 
> - Set the "sysdev" pointer tin the USB device o the device structure that
>   was created by DT or the legacy board file and remove the manual
>   setting of dma_mask,  parms and the dma_configure. This should
>   make everything work as expected in case of DT
> 

oh yeah! I see a proper fix in linux-next tree, thanks for fixing it.