EHCI: maintain the ehci->command value properly
The ehci-hcd driver is a little haphazard about keeping track of the
state of the USBCMD register. The ehci->command field is supposed to
hold the register's value (apart from a few special bits) at all
times, but it isn't maintained properly.
This patch (as1543) cleans up the situation. It keeps ehci->command
up-to-date, and uses that value rather than reading the register from
the hardware whenever possible.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index 402e766..fc9e7cc 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -233,7 +233,6 @@
/* stop schedules, clean any completed work */
if (ehci->rh_state == EHCI_RH_RUNNING)
ehci_quiesce (ehci);
- ehci->command = ehci_readl(ehci, &ehci->regs->command);
ehci_work(ehci);
/* Unlike other USB host controller types, EHCI doesn't have
@@ -374,6 +373,7 @@
ehci_writel(ehci, (u32) ehci->async->qh_dma, &ehci->regs->async_next);
/* restore CMD_RUN, framelist size, and irq threshold */
+ ehci->command |= CMD_RUN;
ehci_writel(ehci, ehci->command, &ehci->regs->command);
ehci->rh_state = EHCI_RH_RUNNING;