Use USB_GADGET_QUIRK_EP_OUT_ALIGNED_SIZE quirk to check if buffer size requires to be aligned to maxpacketsize of an out endpoint. ffs_epfile_io() needs to pad epout buffer to match above condition if quirk is found. Signed-off-by: David Cohen <david.a.cohen@xxxxxxxxxxxxxxx> --- drivers/usb/gadget/f_fs.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/usb/gadget/f_fs.c b/drivers/usb/gadget/f_fs.c index 75e4b78..2988eb7 100644 --- a/drivers/usb/gadget/f_fs.c +++ b/drivers/usb/gadget/f_fs.c @@ -755,10 +755,12 @@ static ssize_t ffs_epfile_io(struct file *file, char __user *buf, size_t len, int read) { struct ffs_epfile *epfile = file->private_data; + struct usb_gadget *gadget = epfile->ffs->gadget; struct ffs_ep *ep; char *data = NULL; ssize_t ret; int halt; + size_t orig_len = len; goto first_try; do { @@ -794,6 +796,21 @@ first_try: goto error; } + /* + * Controller requires buffer size to be aligned to + * maxpacketsize of an out endpoint. + */ + if (gadget->quirks & USB_GADGET_QUIRK_EP_OUT_ALIGNED_SIZE && + read && !IS_ALIGNED(len, ep->ep->desc->wMaxPacketSize)) { + size_t old_len = len; + len = roundup(orig_len, + (size_t)ep->ep->desc->wMaxPacketSize); + if (unlikely(data) && len > old_len) { + kfree(data); + data = NULL; + } + } + /* Allocate & copy */ if (!halt && !data) { data = kzalloc(len, GFP_KERNEL); -- 1.8.4.rc3 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html