[linux-usb-devel] Re: [patch 2.5.66] ehci-hcd, minor hardware tweaks

[David Brownell]

Greg KH wrote:
On Thu, Mar 27, 2003 at 06:48:38PM -0800, David Brownell wrote:

This tweaks the hardware in two minor ways, being more forgiving
of what are either hardware bugs or hard-to-see driver bugs.
- Some silicon seems to mis-handle dummy qtds on occasion,
  writing them into the qh and thus stopping progress unless
  something times it out and cancels it (scsi-eh etc).
  This initializes such qtds slightly differently, so some
  such cases will make the driver automatically recover, and
  so all such errors will fail in the same way.
Also minor diagnostic tweaks for better uniformity/usability.

Please merge to 2.5 and 2.4 trees.


Applied to 2.5, but I get 2 rejects when trying to apply it to 2.4.
The second tweak was in 2.4 already, and the other reject was
a whitespace issue.  Here's the 2.4 version.
- Dave



--- 1.13/drivers/usb/host/ehci-mem.c    Tue Apr  1 19:48:17 2003
+++ edited/drivers/usb/host/ehci-mem.c  Tue Apr  1 20:23:15 2003
@@ -62,6 +62,7 @@
 {
        memset (qtd, 0, sizeof *qtd);
        qtd->qtd_dma = dma;
+       qtd->hw_token = cpu_to_le32 (QTD_STS_HALT);
        qtd->hw_next = EHCI_LIST_END;
        qtd->hw_alt_next = EHCI_LIST_END;
        INIT_LIST_HEAD (&qtd->qtd_list);
--- 1.20/drivers/usb/host/ehci-q.c      Tue Apr  1 19:48:17 2003
+++ edited/drivers/usb/host/ehci-q.c    Tue Apr  1 20:23:15 2003
@@ -137,7 +137,10 @@
                        if (QTD_CERR (token))
                                urb->status = -EPIPE;
                        else {
-                               dbg ("3strikes");
+                               ehci_dbg (ehci, "devpath %s ep%d%s 3strikes\n",
+                                       urb->dev->devpath,
+                                       usb_pipeendpoint (urb->pipe),
+                                       usb_pipein (urb->pipe) ? "in" : "out");
                                urb->status = -EPROTO;
                        }
                /* CERR nonzero + no errors + halt --> stall */
@@ -866,7 +869,7 @@
                         * HC is allowed to fetch the old dummy (4.10.2).
                         */
                        token = qtd->hw_token;
-                       qtd->hw_token = 0;
+                       qtd->hw_token = cpu_to_le32 (QTD_STS_HALT);
                        wmb ();
                        dummy = qh->dummy;
 
@@ -918,8 +921,7 @@
        if (usb_pipein (urb->pipe) && !usb_pipecontrol (urb->pipe))
                epnum |= 0x10;
 
-       vdbg ("%s: submit_async urb %p len %d ep %d-%s qtd %p [qh %p]",
-               hcd_to_bus (&ehci->hcd)->bus_name,
+       ehci_vdbg (ehci, "submit_async urb %p len %d ep%d%s qtd %p [qh %p]\n",
                urb, urb->transfer_buffer_length,
                epnum & 0x0f, (epnum & 0x10) ? "in" : "out",
                qtd, dev ? dev->ep [epnum] : (void *)~0);