On Thu, Feb 9, 2017 at 5:24 PM, Roger Quadros [off-list ref] wrote:

On 09/02/17 13:53, Roger Quadros wrote:

quoted

On 08/02/17 22:43, Jack Pham wrote:

quoted

Hi Peter, Sriram, Arnd,

On Mon, Feb 06, 2017 at 05:13:38PM +0800, Peter Chen wrote:

quoted

From: Arnd Bergmann <arnd@arndb.de>

For xhci-hcd platform device, all the DMA parameters are not
configured properly, notably dma ops for dwc3 devices. So, set
the dma for xhci from sysdev. sysdev is pointing to device that
is known to the system firmware or hardware.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sriram Dash <redacted>
Tested-by: Baolin Wang <redacted>
Tested-by: Vivek Gautam <redacted>
Tested-by: Alexander Sverdlin <redacted>
Signed-off-by: Mathias Nyman <redacted>
---

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 6d33b42..7a9c860 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c

quoted

-   hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
+   hcd = __usb_create_hcd(driver, sysdev, &pdev->dev,
+                          dev_name(&pdev->dev), NULL);

As mentioned already in [1], usb_create_shared_hcd() is called to create
the second bus, however it also needs to be converted.

Not exactly as Roger's suggestion but this worked for me:

-       xhci->shared_hcd = usb_create_shared_hcd(driver, &pdev->dev,
+       xhci->shared_hcd = __usb_create_hcd(driver, sysdev, &pdev->dev,
                        dev_name(&pdev->dev), hcd);

But we're creating a shared_hcd and there is an API for that so why not use it
instead of calling __usb_create_hcd()?

Just realized after I pressed send that there is no sysdev parameter
for create_shared_hcd().

That's right. The create_shared_hcd() makes use of only pdev->dev,
and we need to configure dma for shared_hcd as well though sysdev.

Sorry my mail client didn't show this mail in time. Please ignore my
earlier comment.

quoted

quoted

        if (!xhci->shared_hcd) {
                ret = -ENOMEM;

Without this, SuperSpeed devices fail to enumerate:

 usb 2-1: new SuperSpeed USB device number 2 using xhci-hcd
 usb 2-1: device descriptor read/8, error -11
 usb 2-1: new SuperSpeed USB device number 2 using xhci-hcd
 usb 2-1: device descriptor read/8, error -11
 usb 2-1: new SuperSpeed USB device number 3 using xhci-hcd
 usb 2-1: device descriptor read/8, error -11
 usb 2-1: new SuperSpeed USB device number 3 using xhci-hcd
 usb 2-1: device descriptor read/8, error -11
 <and continues...>

Thanks,
Jack

[1] https://lkml.org/lkml/2016/12/9/240

--
cheers,
-roger
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