qemu/hw/usb
Laurent Vivier 087462c773 ohci: clear pending SOF on suspend
On overcommitted CPU, kernel can be so slow that an interrupt can
be triggered by the device whereas the driver is not ready to receive
it. This drives us into an infinite loop.

On suspend, if a SOF interrupt is raised between the stop of the
device processing and the change of the device internal state to
OHCI_USB_SUSPEND (QEMU stops SOF timer on this state change), this
interrupt is never acknowledged.

This patch clears pending SOF interrupt on OHCI_USB_SUSPEND setting.

Some details:

- ohci_irq(): the OHCI interrupt handler, acknowledges the SOF IRQ
  only if the state of the driver (rh_state) is OHCI_STATE_RUNNING.
  So if this interrupt happens and the driver is not in this state,
  the function is called again and again, moving the system to a
  CPU starvation.

- ohci_rh_suspend(): the function stop the operation and acknowledge
  pending interrupts (but doesn't disable it). Later in the function,
  the device is moved to OHCI_SUSPEND_STATE, and the driver to
  OHCI_RH_SUSPENDED. If between the moment when the interrupt is
  acknowledged and the moment when the device is suspended a new
  interrupt is raised, it will be never acknowledged because the
  driver is now not in OHCI_RH_RUNNING state.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-id: 1452109525-32150-3-git-send-email-lvivier@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2016-01-08 09:29:24 +01:00
..
bus.c usb: print device id in "info usb" monitor command 2015-10-20 09:15:23 +02:00
ccid-card-emulated.c usb: Use g_new() & friends where that makes obvious sense 2015-11-06 15:42:38 +03:00
ccid-card-passthru.c libcacard: use the standalone project 2015-09-23 23:34:17 +02:00
ccid.h hw: move private headers to hw/ subdirectories. 2013-04-08 18:13:16 +02:00
combined-packet.c usb: Fix iovec memleak on combined-packet free 2013-09-19 11:28:40 +02:00
core.c usb: Remove unused functions 2015-04-30 16:05:48 +03:00
desc-msos.c usb: Pair g_malloc() with g_free(), not free() 2015-02-10 09:27:20 +03:00
desc.c usb: add usb_pick_speed 2014-06-02 16:29:00 +02:00
desc.h usb: add CompatibleID support to msos 2014-04-22 12:40:57 +02:00
dev-audio.c usb-audio: increate default buffer size 2015-10-20 09:15:23 +02:00
dev-bluetooth.c usb: usb-bt QOMify 2015-05-08 13:01:06 +02:00
dev-hid.c usb: usb-hid QOMify 2015-05-08 13:01:06 +02:00
dev-hub.c usb: usb-hub QOMify 2015-05-08 13:01:07 +02:00
dev-mtp.c usb-mtp: fix call to trace function 2016-01-08 09:25:50 +01:00
dev-network.c usbnet: Drop usbnet_can_receive 2015-07-27 14:12:18 +01:00
dev-serial.c Include monitor/monitor.h exactly where needed 2015-06-22 18:20:41 +02:00
dev-smartcard-reader.c usb-ccid: add missing wakeup calls 2015-07-17 13:20:53 +02:00
dev-storage.c hw/usb-storage: Check whether BB is inserted 2015-10-23 18:18:23 +02:00
dev-uas.c usb: usb-uas QOMify 2015-05-08 13:01:07 +02:00
dev-wacom.c usb: usb-wacom-tablet QOMify 2015-05-08 13:01:07 +02:00
hcd-ehci-pci.c maint: avoid useless "if (foo) free(foo)" pattern 2015-09-11 10:21:38 +03:00
hcd-ehci-sysbus.c ehci: fix segfault when hot-unplugging ehci controller 2015-03-20 08:50:12 +01:00
hcd-ehci.c ehci: make idt processing more robust 2015-12-15 09:49:03 +01:00
hcd-ehci.h Include monitor/monitor.h exactly where needed 2015-06-22 18:20:41 +02:00
hcd-musb.c Fix remaining warnings from Sparse (void return) 2015-03-19 11:11:55 +03:00
hcd-ohci.c ohci: clear pending SOF on suspend 2016-01-08 09:29:24 +01:00
hcd-uhci.c uhci: controller is halted after reset 2015-05-08 13:01:08 +02:00
hcd-xhci.c usb: Use g_new() & friends where that makes obvious sense 2015-11-06 15:42:38 +03:00
host-legacy.c usb: Improve -usbdevice error reporting a bit 2015-02-18 10:53:10 +01:00
host-libusb.c usb-host: fix usb3ep0quirk test 2015-11-03 11:56:23 +01:00
host-stub.c hmp: Name HMP info handler functions hmp_info_SUBCOMMAND() 2015-02-18 11:58:50 +01:00
host.h usb-host: move legacy cmd line bits 2013-02-19 12:30:05 +01:00
libhw.c dma: eliminate DMAContext 2013-06-20 16:39:52 +02:00
Makefile.objs libcacard: use the standalone project 2015-09-23 23:34:17 +02:00
quirks-ftdi-ids.h usbredir: Add support for buffered bulk input (v2) 2013-01-08 10:56:58 +01:00
quirks-pl2303-ids.h usbredir: Add support for buffered bulk input (v2) 2013-01-08 10:56:58 +01:00
quirks.c usbredir: Add support for buffered bulk input (v2) 2013-01-08 10:56:58 +01:00
quirks.h usbredir: Add support for buffered bulk input (v2) 2013-01-08 10:56:58 +01:00
redirect.c usb: Use g_new() & friends where that makes obvious sense 2015-11-06 15:42:38 +03:00