diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-09-11 04:34:46 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-09-11 04:34:46 -0300 |
commit | 863981e96738983919de841ec669e157e6bdaeb0 (patch) | |
tree | d6d89a12e7eb8017837c057935a2271290907f76 /drivers/usb/host/ehci-hub.c | |
parent | 8dec7c70575785729a6a9e6719a955e9c545bcab (diff) |
Linux-libre 4.7.1-gnupck-4.7.1-gnu
Diffstat (limited to 'drivers/usb/host/ehci-hub.c')
-rw-r--r-- | drivers/usb/host/ehci-hub.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c index ffc90295a..74f62d68f 100644 --- a/drivers/usb/host/ehci-hub.c +++ b/drivers/usb/host/ehci-hub.c @@ -872,15 +872,23 @@ 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 & 0xff) - 1]; - u32 __iomem *hostpc_reg = &ehci->regs->hostpc[(wIndex & 0xff) - 1]; + u32 __iomem *status_reg, *hostpc_reg; u32 temp, temp1, status; unsigned long flags; int retval = 0; unsigned selector; /* + * Avoid underflow while calculating (wIndex & 0xff) - 1. + * The compiler might deduce that wIndex can never be 0 and then + * optimize away the tests for !wIndex below. + */ + temp = wIndex & 0xff; + temp -= (temp > 0); + status_reg = &ehci->regs->port_status[temp]; + hostpc_reg = &ehci->regs->hostpc[temp]; + + /* * FIXME: support SetPortFeatures USB_PORT_FEAT_INDICATOR. * HCS_INDICATOR may say we can change LEDs to off/amber/green. * (track current state ourselves) ... blink for diagnostics, |