Re: [RFC PATCH] USB: PCI: set 32bit DMA mask for PCI based USB controllers

From: Hanjun Guo
Date: Fri Feb 01 2019 - 04:14:56 EST


On 2019/2/1 13:55, Hanjun Guo wrote:
> Hi John,
>
> On 2019/1/31 17:54, John Garry wrote:
>> On 30/01/2019 07:01, Hanjun Guo wrote:
>>> From: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
> [...]
>>>
>>>  drivers/usb/core/hcd-pci.c | 4 ++++
>>>  1 file changed, 4 insertions(+)
>>>
>>> diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c
>>> index 0343246..a9c33e6 100644
>>> --- a/drivers/usb/core/hcd-pci.c
>>> +++ b/drivers/usb/core/hcd-pci.c
>>> @@ -188,6 +188,10 @@ int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
>>>      if (pci_enable_device(dev) < 0)
>>>          return -ENODEV;
>>>
>>> +    retval = dma_coerce_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32));
>>> +    if (retval)
>>> +        return retval;
>>
>> Hi Hanjun,
>>
>> You're missing tidy-up upon failure.
>
> Good catch, needs to disable pci for failure, I will send
> a updated version to address the comments from you and Christoph.

There is a _DMA method which was introduced in ACPI 6.2 to cover
this, I will try that solution then report back.

Thanks
Hanjun