USB: xhci: Re-purpose xhci_quiesce().

xhci_quiesce() is basically a no-op right now.  It's only called if
HC_IS_RUNNING() is true, and the body of the function consists of a
BUG_ON if HC_IS_RUNNING() is false.  For the new xHCI watchdog timer, we
need a new function that clears the xHCI running bit in the command
register, but doesn't wait for the halt status to show up in the status
register.  Re-purpose xhci_quiesce() to do that.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Sarah Sharp 2009-10-27 10:56:33 -07:00 committed by Greg Kroah-Hartman
parent 678539cfaa
commit 4f0f0baef0
2 changed files with 21 additions and 37 deletions

View file

@ -66,6 +66,25 @@ static int handshake(struct xhci_hcd *xhci, void __iomem *ptr,
return -ETIMEDOUT;
}
/*
* Disable interrupts and begin the xHCI halting process.
*/
void xhci_quiesce(struct xhci_hcd *xhci)
{
u32 halted;
u32 cmd;
u32 mask;
mask = ~(XHCI_IRQS);
halted = xhci_readl(xhci, &xhci->op_regs->status) & STS_HALT;
if (!halted)
mask &= ~CMD_RUN;
cmd = xhci_readl(xhci, &xhci->op_regs->command);
cmd &= mask;
xhci_writel(xhci, cmd, &xhci->op_regs->command);
}
/*
* Force HC into halt state.
*
@ -77,20 +96,8 @@ static int handshake(struct xhci_hcd *xhci, void __iomem *ptr,
*/
int xhci_halt(struct xhci_hcd *xhci)
{
u32 halted;
u32 cmd;
u32 mask;
xhci_dbg(xhci, "// Halt the HC\n");
/* Disable all interrupts from the host controller */
mask = ~(XHCI_IRQS);
halted = xhci_readl(xhci, &xhci->op_regs->status) & STS_HALT;
if (!halted)
mask &= ~CMD_RUN;
cmd = xhci_readl(xhci, &xhci->op_regs->command);
cmd &= mask;
xhci_writel(xhci, cmd, &xhci->op_regs->command);
xhci_quiesce(xhci);
return handshake(xhci, &xhci->op_regs->status,
STS_HALT, STS_HALT, XHCI_MAX_HALT_USEC);
@ -124,28 +131,6 @@ int xhci_reset(struct xhci_hcd *xhci)
return handshake(xhci, &xhci->op_regs->command, CMD_RESET, 0, 250 * 1000);
}
/*
* Stop the HC from processing the endpoint queues.
*/
static void xhci_quiesce(struct xhci_hcd *xhci)
{
/*
* Queues are per endpoint, so we need to disable an endpoint or slot.
*
* To disable a slot, we need to insert a disable slot command on the
* command ring and ring the doorbell. This will also free any internal
* resources associated with the slot (which might not be what we want).
*
* A Release Endpoint command sounds better - doesn't free internal HC
* memory, but removes the endpoints from the schedule and releases the
* bandwidth, disables the doorbells, and clears the endpoint enable
* flag. Usually used prior to a set interface command.
*
* TODO: Implement after command ring code is done.
*/
BUG_ON(!HC_IS_RUNNING(xhci_to_hcd(xhci)->state));
xhci_dbg(xhci, "Finished quiescing -- code not written yet\n");
}
#if 0
/* Set up MSI-X table for entry 0 (may claim other entries later) */
@ -490,8 +475,6 @@ void xhci_stop(struct usb_hcd *hcd)
struct xhci_hcd *xhci = hcd_to_xhci(hcd);
spin_lock_irq(&xhci->lock);
if (HC_IS_RUNNING(hcd->state))
xhci_quiesce(xhci);
xhci_halt(xhci);
xhci_reset(xhci);
spin_unlock_irq(&xhci->lock);

View file

@ -1223,6 +1223,7 @@ void xhci_unregister_pci(void);
#endif
/* xHCI host controller glue */
void xhci_quiesce(struct xhci_hcd *xhci);
int xhci_halt(struct xhci_hcd *xhci);
int xhci_reset(struct xhci_hcd *xhci);
int xhci_init(struct usb_hcd *hcd);