On Sun, 10 Jun 2007, Craig W. Nadler wrote:
> >> --- a/drivers/usb/host/ehci-hub.c 2007-06-07 17:27:31.000000000 -0400
> >> +++ b/drivers/usb/host/ehci-hub.c 2007-06-10 13:45:14.000000000 -0400
> >> @@ -444,7 +444,8 @@ static int ehci_hub_control (
> >> ) {
> >> struct ehci_hcd *ehci = hcd_to_ehci (hcd);
> >> int ports = HCS_N_PORTS (ehci->hcs_params);
> >> - u32 __iomem *status_reg = &ehci->regs->port_status[wIndex - 1];
> >> + u8 port_num = wIndex&0xFF;
> >> + u32 __iomem *status_reg = &ehci->regs->port_status[port_num - 1];
> >> u32 temp, status;
> >> unsigned long flags;
> >> int retval = 0;
> >>
> >
> >
> > I have some comments on the contents of this patch -- others may
> > comment on its formatting (or lack thereof!).
> >
> Ok, I'm not sure I know what you're referring to as far as formatting.
> If there is something I'm doing wrong please let me know.
I was referring to the fact that your email client had stripped out all
the tab characters. The latest version of the patch doesn't have this
problem.
> Please note that the new patch is untested. I'm posting it to get comments.
Okay, here's a few. On the whole I like it but it could be improved a
little. To start with, the formatting here is wrong:
> + unsigned port_num = wIndex&0xFF;
There should be spaces around the '&'. This occurs many times.
There also are lots of places where the code follows this pattern:
> - if (!wIndex || wIndex > ports)
> + if (!port_num || port_num > ports)
> goto error;
> - wIndex--;
> + port_num--;
You could make things much simpler by doing it this way instead:
+ unsigned port_num = (wIndex & 0xFF) - 1;
...
- if (!wIndex || wIndex > ports)
+ if (port_num >= ports)
goto error;
- wIndex--;
Then this sort of thing occurs often in your patch:
- ehci->reset_done [wIndex] = jiffies
+ ehci->reset_done [port_num] = jiffies
David's preferred programming style puts a space before an open
bracket (also before an open paren when it is for a function call),
but the preferred style for the kernel is to omit such spaces.
Slowly, piece by piece, we've been removing them. Hence when you
change a line that has the extra space in it, like here, you should
remove the space.
In uhci-hub.c:
@@ -304,7 +304,7 @@ static int uhci_hub_control(struct usb_h
if (wPortChange)
dev_dbg(uhci_dev(uhci), "port %d portsc %04x,%02x\n",
- wIndex, status, lstatus);
+ port, status, lstatus);
*(__le16 *)buf = cpu_to_le16(wPortStatus);
*(__le16 *)(buf + 2) = cpu_to_le16(wPortChange);
Your search-and-replace strategy let you down; you need to specify
port + 1 instead of port.
Finally, having put you to all this trouble, I realized that it wasn't
necessary. The upper bits of wIndex are nonzero only for the
PORT_FEAT_INDICATOR and PORT_FEAT_TEST features, and ehci-hcd is the
only driver to support either of those. Hence it is the only driver is
need of this change. However I think it's not a bad idea to update
every driver anyhow.
Alan Stern
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