[U-Boot] [RFC PATCH v3] usb: limit USB_MAX_XFER_BLK to 256

[Peng Fan]

> Subject: Re: [RFC PATCH v3] usb: limit USB_MAX_XFER_BLK to 256
> 
> Hi,
> 
> I am using an iMX7 with a DataTraveler 3.0 and I’m seeing the same timeout
> error. However, I have CONFIG_DM_USB=y configured so your patch doesn’t
> fix my issue. The USB class queries the EHCI driver for its maximum transfer
> size which is SIZE_MAX. I believe a solution that works with DM is necessary.

Does the patch works for you with non DM usb?

Regards,
Peng

> 
> => usb tree
> USB device tree:
>   1  Hub (480 Mb/s, 0mA)
>   |  u-boot EHCI Host Controller
>   |
>   +-2  Mass Storage (480 Mb/s, 300mA)
>        Kingston DataTraveler 3.0 50E54942694AE23017A55884
> 
> => usb storage
>   Device 0: Vendor: Kingston Rev: PMAP Prod: DataTraveler 3.0
>             Type: Removable Hard Disk
>             Capacity: 59184.0 MB = 57.7 GB (121208832 x 512)
> 
> Best regards,
> Sven
> 
> > On 18 Apr 2019, at 01:45, Marcel Ziswiler <marcel at ziswiler.com> wrote:
> >
> > From: Peng Fan <peng.fan at nxp.com>
> >
> > For Some USB mass storage devices, such as:
> > "
> > - Kingston DataTraveler 2.0 001D7D06CF09B04199C7B3EA
> > - Class: (from Interface) Mass Storage
> > - PacketSize: 64  Configurations: 1
> > - Vendor: 0x0930  Product 0x6545 Version 1.16 "
> > When `usb read 0x80000000 0 0x2000`, we met "EHCI timed out on TD -
> > token=0x80008d80".
> >
> > The devices does not support scsi VPD page, we are not able to get the
> > maximum transfer length for READ(10)/WRITE(10).
> >
> > So we limit this to 256 blocks as READ(6).
> >
> > Signed-off-by: Peng Fan <peng.fan at nxp.com>
> > Acked-by: Marcel Ziswiler <marcel.ziswiler at toradex.com> (cherry picked
> > from commit df0052575b2bc9d66ae73584768e1a457ed5d914)
> >
> > Signed-off-by: Marcel Ziswiler <marcel at ziswiler.com>
> >
> > ---
> > This comes from NXP's downstream and has proven to tremendously
> > improve the situation with those odd USB mass storage aka memory
> > sticks. This is why I post it here asking whether or not this may be
> > something benefiting more people. Any feedback and suggestions are
> welcome.
> >
> > Changes in v3:
> > - Drop the reference to the NXP internal MLK-xxx tracking number as
> > suggested by Peng.
> >
> > Changes in v2:
> > - Fixed spelling in comment as suggested by Igor.
> >
> > common/usb_storage.c | 6 +++++-
> > 1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/common/usb_storage.c b/common/usb_storage.c index
> > 8c889bb1a6..4e284645f5 100644
> > --- a/common/usb_storage.c
> > +++ b/common/usb_storage.c
> > @@ -949,7 +949,11 @@ static void usb_stor_set_max_xfer_blk(struct
> usb_device *udev,
> > 	 * there is enough free heap space left, but the SCSI READ(10) and
> > 	 * WRITE(10) commands are limited to 65535 blocks.
> > 	 */
> > -	blk = USHRT_MAX;
> > +	/*
> > +	 * Some USB mass storage devices have issues, limiting this to 256
> > +	 * fixes this.
> > +	 */
> > +	blk = 256;
> > #else
> > 	blk = 20;
> > #endif
> > --
> > 2.20.1
> >