| From f8bbeabc34aa945ab4275abc9a4dfde0aea798ca Mon Sep 17 00:00:00 2001 |
| From: Sarah Sharp <sarah.a.sharp@linux.intel.com> |
| Date: Thu, 9 Dec 2010 10:29:00 -0800 |
| Subject: xhci: Fix issue with port array setup and buggy hosts. |
| |
| From: Sarah Sharp <sarah.a.sharp@linux.intel.com> |
| |
| commit f8bbeabc34aa945ab4275abc9a4dfde0aea798ca upstream. |
| |
| Fix two bugs with the port array setup. |
| |
| The first bug will only show up with broken xHCI hosts with Extended |
| Capabilities registers that have duplicate port speed entries for the same |
| port. The idea with the original code was to set the port_array entry to |
| -1 if the duplicate port speed entry said the port was a different speed |
| than the original port speed entry. That would mean that later, the port |
| would not be exposed to the USB core. Unfortunately, I forgot a continue |
| statement, and the port_array entry would just be overwritten in the next |
| line. |
| |
| The second bug would happen if there are conflicting port speed registers |
| (so that some entry in port_array is -1), or one of the hardware port |
| registers was not described in the port speed registers (so that some |
| entry in port_array is 0). The code that sets up the usb2_ports array |
| would accidentally claim those ports. That wouldn't really cause any |
| user-visible issues, but it is a bug. |
| |
| This patch should go into the stable trees that have the port array and |
| USB 3.0 port disabling prevention patches. |
| |
| Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| |
| --- |
| drivers/usb/host/xhci-mem.c | 25 +++++++++++++++---------- |
| 1 file changed, 15 insertions(+), 10 deletions(-) |
| |
| --- a/drivers/usb/host/xhci-mem.c |
| +++ b/drivers/usb/host/xhci-mem.c |
| @@ -1677,6 +1677,7 @@ static void xhci_add_in_port(struct xhci |
| xhci->port_array[i] = (u8) -1; |
| } |
| /* FIXME: Should we disable the port? */ |
| + continue; |
| } |
| xhci->port_array[i] = major_revision; |
| if (major_revision == 0x03) |
| @@ -1755,16 +1756,20 @@ static int xhci_setup_port_arrays(struct |
| return -ENOMEM; |
| |
| port_index = 0; |
| - for (i = 0; i < num_ports; i++) |
| - if (xhci->port_array[i] != 0x03) { |
| - xhci->usb2_ports[port_index] = |
| - &xhci->op_regs->port_status_base + |
| - NUM_PORT_REGS*i; |
| - xhci_dbg(xhci, "USB 2.0 port at index %u, " |
| - "addr = %p\n", i, |
| - xhci->usb2_ports[port_index]); |
| - port_index++; |
| - } |
| + for (i = 0; i < num_ports; i++) { |
| + if (xhci->port_array[i] == 0x03 || |
| + xhci->port_array[i] == 0 || |
| + xhci->port_array[i] == -1) |
| + continue; |
| + |
| + xhci->usb2_ports[port_index] = |
| + &xhci->op_regs->port_status_base + |
| + NUM_PORT_REGS*i; |
| + xhci_dbg(xhci, "USB 2.0 port at index %u, " |
| + "addr = %p\n", i, |
| + xhci->usb2_ports[port_index]); |
| + port_index++; |
| + } |
| } |
| if (xhci->num_usb3_ports) { |
| xhci->usb3_ports = kmalloc(sizeof(*xhci->usb3_ports)* |
