Re: [PATCH v2 1/1] usb: xhci: do not create and register shared_hcd when USB3.0 is disabled

[Thang Q. Nguyen]

On Mon, Mar 5, 2018 at 5:22 PM, Thang Q. Nguyen <tqnguyen@xxxxxxx> wrote:
> On Mon, Jan 29, 2018 at 5:24 PM, Thang Q. Nguyen <tqnguyen@xxxxxxx> wrote:
>> From: Tung Nguyen <tunguyen@xxxxxxx>
>>
>> Currently, hcd->shared_hcd always creates and registers to the usb-core.
>> If, for some reasons, USB3 downstream port is disabled, no roothub port for
>> USB3.0 is found. This causes kernel to display an error:
>> hub 2-0:1.0: config failed, hub doesn't have any ports! (err -19)
>> This patch checks and registers shared_hcd if USB3.0 downstream
>> port is available.
>>
>> Signed-off-by: Tung Nguyen <tunguyen@xxxxxxx>
>> ---
>>  drivers/usb/host/xhci-plat.c |  9 ++++++---
>>  drivers/usb/host/xhci.c      | 13 +++++++++++++
>>  2 files changed, 19 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
>> index 6f03830..bdb3975 100644
>> --- a/drivers/usb/host/xhci-plat.c
>> +++ b/drivers/usb/host/xhci-plat.c
>> @@ -293,9 +293,12 @@ static int xhci_plat_probe(struct platform_device *pdev)
>>         if (HCC_MAX_PSA(xhci->hcc_params) >= 4)
>>                 xhci->shared_hcd->can_do_streams = 1;
>>
>> -       ret = usb_add_hcd(xhci->shared_hcd, irq, IRQF_SHARED);
>> -       if (ret)
>> -               goto dealloc_usb2_hcd;
>> +       /* Just add the shared_hcd when USB3.0 downstream port is available */
>> +       if (xhci->num_usb3_ports > 0) {
>> +               ret = usb_add_hcd(xhci->shared_hcd, irq, IRQF_SHARED);
>> +               if (ret)
>> +                       goto dealloc_usb2_hcd;
>> +       }
>>
>>         device_enable_async_suspend(&pdev->dev);
>>         pm_runtime_put_noidle(&pdev->dev);
>> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
>> index 1eeb339..9d3b1ab 100644
>> --- a/drivers/usb/host/xhci.c
>> +++ b/drivers/usb/host/xhci.c
>> @@ -611,6 +611,19 @@ int xhci_run(struct usb_hcd *hcd)
>>                 if (ret)
>>                         xhci_free_command(xhci, command);
>>         }
>> +       /*
>> +        * In case that the USB3.0 downstream port is not available
>> +        * No one triggers to start the xHC which should be done
>> +        * before finishing xhci_run
>> +        */
>> +       if (xhci->num_usb3_ports == 0) {
>> +               if (xhci_start(xhci)) {
>> +                       xhci_halt(xhci);
>> +                       return -ENODEV;
>> +               }
>> +               xhci->cmd_ring_state = CMD_RING_STATE_RUNNING;
>> +       }
>> +
>>         xhci_dbg_trace(xhci, trace_xhci_dbg_init,
>>                         "Finished xhci_run for USB2 roothub");
>>
>> --
>> 1.8.3.1
>>
> Hi,
> Do you have any comment on the patch?
Hi,
Do you have any comment on the patch?