USB: EHCI: fix up locking
This patch (as1588) adjusts the locking in ehci-hcd's various halt, shutdown, and suspend/resume pathways. We want to hold the spinlock while writing device registers and accessing shared variables, but not while polling in a loop. In addition, there's no need to call ehci_work() at times when no URBs can be active, i.e., in ehci_stop() and ehci_bus_suspend(). Finally, ehci_adjust_port_wakeup_flags() is called only in situations where interrupts are enabled; therefore it can use spin_lock_irq rather than spin_lock_irqsave. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Alan Stern
Greg Kroah-Hartman
Родитель
f428907822
Коммит
c4f3476436
|
|
@ -167,21 +167,24 @@ static int tdi_in_host_mode (struct ehci_hcd *ehci)
|
|||
return (tmp & 3) == USBMODE_CM_HC;
|
||||
}
|
||||
|
||||
/* force HC to halt state from unknown (EHCI spec section 2.3) */
|
||||
/*
|
||||
* Force HC to halt state from unknown (EHCI spec section 2.3).
|
||||
* Must be called with interrupts enabled and the lock not held.
|
||||
*/
|
||||
static int ehci_halt (struct ehci_hcd *ehci)
|
||||
{
|
||||
u32 temp = ehci_readl(ehci, &ehci->regs->status);
|
||||
u32 temp;
|
||||
|
||||
spin_lock_irq(&ehci->lock);
|
||||
|
||||
/* disable any irqs left enabled by previous code */
|
||||
ehci_writel(ehci, 0, &ehci->regs->intr_enable);
|
||||
|
||||
if (ehci_is_TDI(ehci) && tdi_in_host_mode(ehci) == 0) {
|
||||
if (ehci_is_TDI(ehci) && !tdi_in_host_mode(ehci)) {
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
return 0;
|
||||
}
|
||||
|
||||
if ((temp & STS_HALT) != 0)
|
||||
return 0;
|
||||
|
||||
/*
|
||||
* This routine gets called during probe before ehci->command
|
||||
* has been initialized, so we can't rely on its value.
|
||||
|
|
@ -190,7 +193,11 @@ static int ehci_halt (struct ehci_hcd *ehci)
|
|||
temp = ehci_readl(ehci, &ehci->regs->command);
|
||||
temp &= ~(CMD_RUN | CMD_IAAD);
|
||||
ehci_writel(ehci, temp, &ehci->regs->command);
|
||||
return handshake (ehci, &ehci->regs->status,
|
||||
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
synchronize_irq(ehci_to_hcd(ehci)->irq);
|
||||
|
||||
return handshake(ehci, &ehci->regs->status,
|
||||
STS_HALT, STS_HALT, 16 * 125);
|
||||
}
|
||||
|
||||
|
|
@ -210,7 +217,10 @@ static void tdi_reset (struct ehci_hcd *ehci)
|
|||
ehci_writel(ehci, tmp, &ehci->regs->usbmode);
|
||||
}
|
||||
|
||||
/* reset a non-running (STS_HALT == 1) controller */
|
||||
/*
|
||||
* Reset a non-running (STS_HALT == 1) controller.
|
||||
* Must be called with interrupts enabled and the lock not held.
|
||||
*/
|
||||
static int ehci_reset (struct ehci_hcd *ehci)
|
||||
{
|
||||
int retval;
|
||||
|
|
@ -248,7 +258,10 @@ static int ehci_reset (struct ehci_hcd *ehci)
|
|||
return retval;
|
||||
}
|
||||
|
||||
/* idle the controller (from running) */
|
||||
/*
|
||||
* Idle the controller (turn off the schedules).
|
||||
* Must be called with interrupts enabled and the lock not held.
|
||||
*/
|
||||
static void ehci_quiesce (struct ehci_hcd *ehci)
|
||||
{
|
||||
u32 temp;
|
||||
|
|
@ -261,8 +274,10 @@ static void ehci_quiesce (struct ehci_hcd *ehci)
|
|||
handshake(ehci, &ehci->regs->status, STS_ASS | STS_PSS, temp, 16 * 125);
|
||||
|
||||
/* then disable anything that's still active */
|
||||
spin_lock_irq(&ehci->lock);
|
||||
ehci->command &= ~(CMD_ASE | CMD_PSE);
|
||||
ehci_writel(ehci, ehci->command, &ehci->regs->command);
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
|
||||
/* hardware can take 16 microframes to turn off ... */
|
||||
handshake(ehci, &ehci->regs->status, STS_ASS | STS_PSS, 0, 16 * 125);
|
||||
|
|
@ -301,11 +316,14 @@ static void ehci_turn_off_all_ports(struct ehci_hcd *ehci)
|
|||
|
||||
/*
|
||||
* Halt HC, turn off all ports, and let the BIOS use the companion controllers.
|
||||
* Should be called with ehci->lock held.
|
||||
* Must be called with interrupts enabled and the lock not held.
|
||||
*/
|
||||
static void ehci_silence_controller(struct ehci_hcd *ehci)
|
||||
{
|
||||
ehci_halt(ehci);
|
||||
|
||||
spin_lock_irq(&ehci->lock);
|
||||
ehci->rh_state = EHCI_RH_HALTED;
|
||||
ehci_turn_off_all_ports(ehci);
|
||||
|
||||
/* make BIOS/etc use companion controller during reboot */
|
||||
|
|
@ -313,6 +331,7 @@ static void ehci_silence_controller(struct ehci_hcd *ehci)
|
|||
|
||||
/* unblock posted writes */
|
||||
ehci_readl(ehci, &ehci->regs->configured_flag);
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
}
|
||||
|
||||
/* ehci_shutdown kick in for silicon on any bus (not just pci, etc).
|
||||
|
|
@ -325,10 +344,11 @@ static void ehci_shutdown(struct usb_hcd *hcd)
|
|||
|
||||
spin_lock_irq(&ehci->lock);
|
||||
ehci->rh_state = EHCI_RH_STOPPING;
|
||||
ehci_silence_controller(ehci);
|
||||
ehci->enabled_hrtimer_events = 0;
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
|
||||
ehci_silence_controller(ehci);
|
||||
|
||||
hrtimer_cancel(&ehci->hrtimer);
|
||||
}
|
||||
|
||||
|
|
@ -400,11 +420,11 @@ static void ehci_stop (struct usb_hcd *hcd)
|
|||
|
||||
spin_lock_irq(&ehci->lock);
|
||||
ehci->enabled_hrtimer_events = 0;
|
||||
ehci_quiesce(ehci);
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
|
||||
ehci_quiesce(ehci);
|
||||
ehci_silence_controller(ehci);
|
||||
ehci_reset (ehci);
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
|
||||
hrtimer_cancel(&ehci->hrtimer);
|
||||
remove_sysfs_files(ehci);
|
||||
|
|
@ -412,8 +432,6 @@ static void ehci_stop (struct usb_hcd *hcd)
|
|||
|
||||
/* root hub is shut down separately (first, when possible) */
|
||||
spin_lock_irq (&ehci->lock);
|
||||
if (ehci->async)
|
||||
ehci_work (ehci);
|
||||
end_free_itds(ehci);
|
||||
spin_unlock_irq (&ehci->lock);
|
||||
ehci_mem_cleanup (ehci);
|
||||
|
|
|
|||
|
|
@ -59,6 +59,7 @@ static void ehci_handover_companion_ports(struct ehci_hcd *ehci)
|
|||
/* Give the connections some time to appear */
|
||||
msleep(20);
|
||||
|
||||
spin_lock_irq(&ehci->lock);
|
||||
port = HCS_N_PORTS(ehci->hcs_params);
|
||||
while (port--) {
|
||||
if (test_bit(port, &ehci->owned_ports)) {
|
||||
|
|
@ -70,23 +71,30 @@ static void ehci_handover_companion_ports(struct ehci_hcd *ehci)
|
|||
clear_bit(port, &ehci->owned_ports);
|
||||
else if (test_bit(port, &ehci->companion_ports))
|
||||
ehci_writel(ehci, status & ~PORT_PE, reg);
|
||||
else
|
||||
else {
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
ehci_hub_control(hcd, SetPortFeature,
|
||||
USB_PORT_FEAT_RESET, port + 1,
|
||||
NULL, 0);
|
||||
spin_lock_irq(&ehci->lock);
|
||||
}
|
||||
}
|
||||
}
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
|
||||
if (!ehci->owned_ports)
|
||||
return;
|
||||
msleep(90); /* Wait for resets to complete */
|
||||
|
||||
spin_lock_irq(&ehci->lock);
|
||||
port = HCS_N_PORTS(ehci->hcs_params);
|
||||
while (port--) {
|
||||
if (test_bit(port, &ehci->owned_ports)) {
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
ehci_hub_control(hcd, GetPortStatus,
|
||||
0, port + 1,
|
||||
(char *) &buf, sizeof(buf));
|
||||
spin_lock_irq(&ehci->lock);
|
||||
|
||||
/* The companion should now own the port,
|
||||
* but if something went wrong the port must not
|
||||
|
|
@ -105,6 +113,7 @@ static void ehci_handover_companion_ports(struct ehci_hcd *ehci)
|
|||
}
|
||||
|
||||
ehci->owned_ports = 0;
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
}
|
||||
|
||||
static int ehci_port_change(struct ehci_hcd *ehci)
|
||||
|
|
@ -133,7 +142,6 @@ static void ehci_adjust_port_wakeup_flags(struct ehci_hcd *ehci,
|
|||
{
|
||||
int port;
|
||||
u32 temp;
|
||||
unsigned long flags;
|
||||
|
||||
/* If remote wakeup is enabled for the root hub but disabled
|
||||
* for the controller, we must adjust all the port wakeup flags
|
||||
|
|
@ -143,7 +151,7 @@ static void ehci_adjust_port_wakeup_flags(struct ehci_hcd *ehci,
|
|||
if (!ehci_to_hcd(ehci)->self.root_hub->do_remote_wakeup || do_wakeup)
|
||||
return;
|
||||
|
||||
spin_lock_irqsave(&ehci->lock, flags);
|
||||
spin_lock_irq(&ehci->lock);
|
||||
|
||||
/* clear phy low-power mode before changing wakeup flags */
|
||||
if (ehci->has_hostpc) {
|
||||
|
|
@ -154,9 +162,9 @@ static void ehci_adjust_port_wakeup_flags(struct ehci_hcd *ehci,
|
|||
temp = ehci_readl(ehci, hostpc_reg);
|
||||
ehci_writel(ehci, temp & ~HOSTPC_PHCD, hostpc_reg);
|
||||
}
|
||||
spin_unlock_irqrestore(&ehci->lock, flags);
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
msleep(5);
|
||||
spin_lock_irqsave(&ehci->lock, flags);
|
||||
spin_lock_irq(&ehci->lock);
|
||||
}
|
||||
|
||||
port = HCS_N_PORTS(ehci->hcs_params);
|
||||
|
|
@ -194,7 +202,7 @@ static void ehci_adjust_port_wakeup_flags(struct ehci_hcd *ehci,
|
|||
if (!suspending && ehci_port_change(ehci))
|
||||
usb_hcd_resume_root_hub(ehci_to_hcd(ehci));
|
||||
|
||||
spin_unlock_irqrestore(&ehci->lock, flags);
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
}
|
||||
|
||||
static int ehci_bus_suspend (struct usb_hcd *hcd)
|
||||
|
|
@ -209,6 +217,9 @@ static int ehci_bus_suspend (struct usb_hcd *hcd)
|
|||
if (time_before (jiffies, ehci->next_statechange))
|
||||
msleep(5);
|
||||
|
||||
/* stop the schedules */
|
||||
ehci_quiesce(ehci);
|
||||
|
||||
spin_lock_irq (&ehci->lock);
|
||||
|
||||
/* Once the controller is stopped, port resumes that are already
|
||||
|
|
@ -224,10 +235,6 @@ static int ehci_bus_suspend (struct usb_hcd *hcd)
|
|||
}
|
||||
}
|
||||
|
||||
/* stop schedules, clean any completed work */
|
||||
ehci_quiesce(ehci);
|
||||
ehci_work(ehci);
|
||||
|
||||
/* Unlike other USB host controller types, EHCI doesn't have
|
||||
* any notion of "global" or bus-wide suspend. The driver has
|
||||
* to manually suspend all the active unsuspended ports, and
|
||||
|
|
@ -289,6 +296,7 @@ static int ehci_bus_suspend (struct usb_hcd *hcd)
|
|||
"succeeded" : "failed");
|
||||
}
|
||||
}
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
|
||||
/* Apparently some devices need a >= 1-uframe delay here */
|
||||
if (ehci->bus_suspended)
|
||||
|
|
@ -296,6 +304,8 @@ static int ehci_bus_suspend (struct usb_hcd *hcd)
|
|||
|
||||
/* turn off now-idle HC */
|
||||
ehci_halt (ehci);
|
||||
|
||||
spin_lock_irq(&ehci->lock);
|
||||
ehci->rh_state = EHCI_RH_SUSPENDED;
|
||||
|
||||
end_unlink_async(ehci);
|
||||
|
|
@ -424,13 +434,14 @@ static int ehci_bus_resume (struct usb_hcd *hcd)
|
|||
}
|
||||
|
||||
ehci->next_statechange = jiffies + msecs_to_jiffies(5);
|
||||
spin_unlock_irq(&ehci->lock);
|
||||
|
||||
ehci_handover_companion_ports(ehci);
|
||||
|
||||
/* Now we can safely re-enable irqs */
|
||||
ehci_writel(ehci, INTR_MASK, &ehci->regs->intr_enable);
|
||||
(void) ehci_readl(ehci, &ehci->regs->intr_enable);
|
||||
|
||||
spin_unlock_irq (&ehci->lock);
|
||||
ehci_handover_companion_ports(ehci);
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
|
@ -1018,7 +1029,9 @@ static int ehci_hub_control (
|
|||
case USB_PORT_FEAT_TEST:
|
||||
if (!selector || selector > 5)
|
||||
goto error;
|
||||
spin_unlock_irqrestore(&ehci->lock, flags);
|
||||
ehci_quiesce(ehci);
|
||||
spin_lock_irqsave(&ehci->lock, flags);
|
||||
|
||||
/* Put all enabled ports into suspend */
|
||||
while (ports--) {
|
||||
|
|
@ -1030,7 +1043,11 @@ static int ehci_hub_control (
|
|||
ehci_writel(ehci, temp | PORT_SUSPEND,
|
||||
sreg);
|
||||
}
|
||||
|
||||
spin_unlock_irqrestore(&ehci->lock, flags);
|
||||
ehci_halt(ehci);
|
||||
spin_lock_irqsave(&ehci->lock, flags);
|
||||
|
||||
temp = ehci_readl(ehci, status_reg);
|
||||
temp |= selector << 16;
|
||||
ehci_writel(ehci, temp, status_reg);
|
||||
|
|
|
|||
|
|
@ -445,12 +445,11 @@ static int controller_suspend(struct device *dev)
|
|||
if (time_before(jiffies, ehci->next_statechange))
|
||||
msleep(10);
|
||||
|
||||
spin_lock_irqsave(&ehci->lock, flags);
|
||||
|
||||
tegra->port_speed = (readl(&hw->port_status[0]) >> 26) & 0x3;
|
||||
ehci_halt(ehci);
|
||||
clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
|
||||
|
||||
spin_lock_irqsave(&ehci->lock, flags);
|
||||
tegra->port_speed = (readl(&hw->port_status[0]) >> 26) & 0x3;
|
||||
clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
|
||||
spin_unlock_irqrestore(&ehci->lock, flags);
|
||||
|
||||
tegra_ehci_power_down(hcd);
|
||||
|
|
|
|||
Загрузка…
Ссылка в новой задаче