USB: xhci: unsigned char never equals -1

There were some places that compared port_speed == -1 where port_speed
is a u8.  This doesn't work unless we cast the -1 to u8.  Some places
did it correctly.

Instead of using -1 directly, I've created a DUPLICATE_ENTRY define
which does the cast and is more descriptive as well.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>

3 files changed, 9 insertions, 6 deletions

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index a003e79aacdc..ab7fc2b71a8c 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -846,7 +846,7 @@ static u32 xhci_find_real_port_number(struct xhci_hcd *xhci,
                  * Skip ports that don't have known speeds, or have duplicate
                  * Extended Capabilities port speed entries.
                  */
-                if (port_speed == 0 || port_speed == -1)
+                if (port_speed == 0 || port_speed == DUPLICATE_ENTRY)
                         continue;
 
                 /*
@@ -1727,12 +1727,12 @@ static void xhci_add_in_port(struct xhci_hcd *xhci, unsigned int num_ports,
                          * found a similar duplicate.
                          */
                         if (xhci->port_array[i] != major_revision &&
-                                xhci->port_array[i] != (u8) -1) {
+                                xhci->port_array[i] != DUPLICATE_ENTRY) {
                                 if (xhci->port_array[i] == 0x03)
                                         xhci->num_usb3_ports--;
                                 else
                                         xhci->num_usb2_ports--;
-                                xhci->port_array[i] = (u8) -1;
+                                xhci->port_array[i] = DUPLICATE_ENTRY;
                         }
                         /* FIXME: Should we disable the port? */
                         continue;
@@ -1831,7 +1831,7 @@ static int xhci_setup_port_arrays(struct xhci_hcd *xhci, gfp_t flags)
                 for (i = 0; i < num_ports; i++) {
                         if (xhci->port_array[i] == 0x03 ||
                                         xhci->port_array[i] == 0 ||
-                                        xhci->port_array[i] == -1)
+                                        xhci->port_array[i] == DUPLICATE_ENTRY)
                                 continue;
 
                         xhci->usb2_ports[port_index] =
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index cfc1ad92473f..c6d1462aa1c3 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1209,7 +1209,7 @@ static unsigned int find_faked_portnum_from_hw_portnum(struct usb_hcd *hcd,
                  * Skip ports that don't have known speeds, or have duplicate
                  * Extended Capabilities port speed entries.
                  */
-                if (port_speed == 0 || port_speed == -1)
+                if (port_speed == 0 || port_speed == DUPLICATE_ENTRY)
                         continue;
 
                 /*
@@ -1260,7 +1260,7 @@ static void handle_port_status(struct xhci_hcd *xhci,
                                 port_id);
                 goto cleanup;
         }
-        if (major_revision == (u8) -1) {
+        if (major_revision == DUPLICATE_ENTRY) {
                 xhci_warn(xhci, "Event for port %u duplicated in"
                                 "Extended Capabilities, ignoring.\n",
                                 port_id);
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 91b1a237c11e..bdb78f51735e 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -348,6 +348,9 @@ struct xhci_op_regs {
 /* Initiate a warm port reset - complete when PORT_WRC is '1' */
 #define PORT_WR         (1 << 31)
 
+/* We mark duplicate entries with -1 */
+#define DUPLICATE_ENTRY ((u8)(-1))
+
 /* Port Power Management Status and Control - port_power_base bitmasks */
 /* Inactivity timer value for transitions into U1, in microseconds.
  * Timeout can be up to 127us.  0xFF means an infinite timeout.