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path: root/drivers/usb/host/ohci-hub.c
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2020-11-13usb: fix a few cases of -WfallthroughNick Desaulniers1-0/+1
The "fallthrough" pseudo-keyword was added as a portable way to denote intentional fallthrough. Clang will still warn on cases where there is a fallthrough to an immediate break. Add explicit breaks for those cases. Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Link: https://lore.kernel.org/r/20201111014716.260633-1-ndesaulniers@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-10USB: OHCI: Use fallthrough pseudo-keywordGustavo A. R. Silva1-1/+1
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Link: https://lore.kernel.org/r/20200707195351.GA4061@embeddedor Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-15ohci-hcd: Fix race condition caused by ohci_urb_enqueue() and io_watchdog_func()Shigeru Yoshida1-1/+3
Running io_watchdog_func() while ohci_urb_enqueue() is running can cause a race condition where ohci->prev_frame_no is corrupted and the watchdog can mis-detect following error: ohci-platform 664a0800.usb: frame counter not updating; disabled ohci-platform 664a0800.usb: HC died; cleaning up Specifically, following scenario causes a race condition: 1. ohci_urb_enqueue() calls spin_lock_irqsave(&ohci->lock, flags) and enters the critical section 2. ohci_urb_enqueue() calls timer_pending(&ohci->io_watchdog) and it returns false 3. ohci_urb_enqueue() sets ohci->prev_frame_no to a frame number read by ohci_frame_no(ohci) 4. ohci_urb_enqueue() schedules io_watchdog_func() with mod_timer() 5. ohci_urb_enqueue() calls spin_unlock_irqrestore(&ohci->lock, flags) and exits the critical section 6. Later, ohci_urb_enqueue() is called 7. ohci_urb_enqueue() calls spin_lock_irqsave(&ohci->lock, flags) and enters the critical section 8. The timer scheduled on step 4 expires and io_watchdog_func() runs 9. io_watchdog_func() calls spin_lock_irqsave(&ohci->lock, flags) and waits on it because ohci_urb_enqueue() is already in the critical section on step 7 10. ohci_urb_enqueue() calls timer_pending(&ohci->io_watchdog) and it returns false 11. ohci_urb_enqueue() sets ohci->prev_frame_no to new frame number read by ohci_frame_no(ohci) because the frame number proceeded between step 3 and 6 12. ohci_urb_enqueue() schedules io_watchdog_func() with mod_timer() 13. ohci_urb_enqueue() calls spin_unlock_irqrestore(&ohci->lock, flags) and exits the critical section, then wake up io_watchdog_func() which is waiting on step 9 14. io_watchdog_func() enters the critical section 15. io_watchdog_func() calls ohci_frame_no(ohci) and set frame_no variable to the frame number 16. io_watchdog_func() compares frame_no and ohci->prev_frame_no On step 16, because this calling of io_watchdog_func() is scheduled on step 4, the frame number set in ohci->prev_frame_no is expected to the number set on step 3. However, ohci->prev_frame_no is overwritten on step 11. Because step 16 is executed soon after step 11, the frame number might not proceed, so ohci->prev_frame_no must equals to frame_no. To address above scenario, this patch introduces a special sentinel value IO_WATCHDOG_OFF and set this value to ohci->prev_frame_no when the watchdog is not pending or running. When ohci_urb_enqueue() schedules the watchdog (step 4 and 12 above), it compares ohci->prev_frame_no to IO_WATCHDOG_OFF so that ohci->prev_frame_no is not overwritten while io_watchdog_func() is running. Signed-off-by: Shigeru Yoshida <Shigeru.Yoshida@windriver.com> Signed-off-by: Haiqing Bai <Haiqing.Bai@windriver.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04USB: add SPDX identifiers to all remaining files in drivers/usb/Greg Kroah-Hartman1-0/+1
It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the drivers/usb/ and include/linux/usb* files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com> Acked-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-10ohci-hub: fix typo in dbg_port macroJelle Martijn Kok1-13/+13
The "dbg_port" macro uses the "outside" parameter (="temp") instead of the parameters (="value") given in the macro. As the macro can look outside its definition this causes no direct problem. Signed-off-by: Jelle Martijn Kok <jmkok@youcom.nl> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-04-03ohci-hub: use USB_DT_HUBSergei Shtylyov1-1/+1
Fix using the bare number to set the 'bDescriptorType' field of the Hub Descriptor while the value is #define'd in <linux/usb/ch11.h>. Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-25ohci-hub: use HUB_CHAR_*Sergei Shtylyov1-5/+5
Fix using the bare numbers to set the 'wHubCharacteristics' field of the Hub Descriptor while the values are #define'd in <linux/usb/ch11.h>. While at it, fix the indentation. Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-24usb: hub: rename khubd to hub_wq in documentation and commentsPetr Mladek1-2/+2
USB hub has started to use a workqueue instead of kthread. Let's update the documentation and comments here and there. This patch mostly just replaces "khubd" with "hub_wq". There are only few exceptions where the whole sentence was updated. These more complicated changes can be found in the following files: Documentation/usb/hotplug.txt drivers/net/usb/usbnet.c drivers/usb/core/hcd.c drivers/usb/host/ohci-hcd.c drivers/usb/host/xhci.c Signed-off-by: Petr Mladek <pmladek@suse.cz> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-19USB: OHCI: add I/O watchdog for orphan TDsAlan Stern1-0/+3
Some OHCI controllers have a bug: They fail to add completed TDs to the done queue. Examining this queue is the only method ohci-hcd has for telling when a transfer is complete; failure to add a TD can result in an URB that never completes and cannot be unlinked. This patch adds a watchdog routine to ohci-hcd. The routine periodically scans the active ED and TD lists, looking for TDs which are finished but not on the done queue. When one is found, and it is certain that the controller hardware will never add the TD to the done queue, the watchdog routine manually puts the TD on the done list so that it can be handled normally. The watchdog routine also checks for a condition indicating the controller has died. If the done queue is non-empty but the HccaDoneHead pointer hasn't been updated for a few hundred milliseconds, we assume the controller will never update it and therefore is dead. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-19USB: OHCI: make URB completions single-threadedAlan Stern1-4/+2
URBs for a particular endpoint should complete sequentially. That is, we shouldn't call the completion handler for one URB until the handler for the previous URB has returned. When the OHCI watchdog routine is added, there will be two paths for completing URBs: interrupt handler and watchdog routine. Their activities have to be synchronized so that completions don't occur in multiple threads concurrently. For that purpose, this patch creates an ohci_work() routine which will be responsible for calling process_done_list() and finish_unlinks(), the two routines that detect when an URB is complete. Everything will funnel through ohci_work(), and it will be careful not to run in more than one thread at a time. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-19USB: OHCI: redesign the TD done listAlan Stern1-2/+4
This patch changes the way ohci-hcd handles the TD done list. In addition to relying on the TD pointers stored by the controller hardware, we need to handle TDs that the hardware has forgotten about. This means the list has to exist even while the dl_done_list() routine isn't running. That function essentially gets split in two: update_done_list() reads the TD pointers stored by the hardware and adds the TDs to the done list, and process_done_list() scans through the list to handle URB completions. When we detect a TD that the hardware forgot about, we will be able to add it to the done list manually and then process it normally. Since the list is really a queue, and because there can be a lot of TDs, keep the existing singly linked implementation. To insure that URBs are given back in order of submission, whenever a TD is added to the done list, all the preceding TDs for the same endpoint must be added as well (going back to the first one that isn't already on the done list). The done list manipulations must all be protected by the private lock. The scope of the lock is expanded in preparation for the watchdog routine to be added in a later patch. We have to be more careful about giving back unlinked URBs. Since TDs may be added to the done list by the watchdog routine and not in response to a controller interrupt, we have to check explicitly to make sure all the URB's TDs that were added to the done list have been processed before giving back the URB. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-20Merge 3.15-rc5 into usb-nextGreg Kroah-Hartman1-0/+18
We need these USB fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-04USB: OHCI: fix problem with global suspend on ATI controllersAlan Stern1-0/+18
Some OHCI controllers from ATI/AMD seem to have difficulty with "global" USB suspend, that is, suspending an entire USB bus without setting the suspend feature for each port connected to a device. When we try to resume the child devices, the controller gives timeout errors on the unsuspended ports, requiring resets, and can even cause ohci-hcd to hang; see http://marc.info/?l=linux-usb&m=139514332820398&w=2 and the following messages. This patch fixes the problem by adding a new quirk flag to ohci-hcd. The flag causes the ohci_rh_suspend() routine to suspend each unsuspended, enabled port before suspending the root hub. This effectively converts the "global" suspend to an ordinary root-hub suspend. There is no need to unsuspend these ports when the root hub is resumed, because the child devices will be resumed anyway in the course of a normal system resume ("global" suspend is never used for runtime PM). This patch should be applied to all stable kernels which include commit 0aa2832dd0d9 (USB: use "global suspend" for system sleep on USB-2 buses) or a backported version thereof. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Peter Münster <pmlists@free.fr> Tested-by: Peter Münster <pmlists@free.fr> CC: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-25USB: OHCI: Export the OHCI hub control and status_data functionsLaurent Pinchart1-4/+4
Platform drivers sometimes need to perform specific handling of hub control requests and status data. Make this possible by exporting the ohci_hub_control() and ohci_hub_status_data() functions which can then be called from custom hub operations in the default case. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-03ohci: no conditional debugging in root hub hadlingOliver Neukum1-4/+2
With dynamic debugging the selection is done in user space Signed-off-by: Oliver Neukum <oneukum@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-20USB: OHCI: fix and explain sparse errorsAlan Stern1-4/+5
This patch fixes an endian-related error in ohci-hcd (detected by sparse) and clarifies a comment explaining a peculiar locking arrangement that sparse warns about. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-30USB: OHCI: prepare to make ohci-hcd a library moduleManjunath Goudar1-1/+0
This patch prepares ohci-hcd for being split up into a core library and separate platform driver modules. A generic ohci_hc_driver structure is created, containing all the "standard" values, and a new mechanism is added whereby a driver module can specify a set of overrides to those values. In addition the ohci_restart(),ohci_suspend() and ohci_resume() routines need to be EXPORTed for use by the drivers. Added ohci_setip(() and ohci_start() routine for to start the generic controller rather than each having its own idiosyncratic approach. This allow to clean duplicated code in most of SOC driver In V2: -ohci_hcd_init() ohci_run() and ohci_stop() are not made non-static. -Adds the ohci_setup() and ohci_start() routine. In V3: -purpose of ohci_setup() and ohci_start() function description written in the patch description. -ohci_init() are not made non-static but now called beginning of the ohci_restart(). -ohci_run() signature change reverted back. -unrelated changes removed. -duplicate comment line removed. -inline ohci_suspend() and ohci_resume() is not needed so removed from ohci.h file. In V4: -ohci-init() EXPORTed because it is called by all bus glue modules. -ohci-setup() removed from 1/2 added into 2/2 patch. In V5: -Again ohci_setup() is added and EXPORTed because to replace the ohci_init() from all bus glues. -ohci_init() is not made non-static function. In V6: -ohci_init() call is removed from ohci_quirk_nec_worker(), because it is already called in ohci_restart(). In V8: -ohci_hcd_init() is called by ohci_setup() to make generic ohci initialization in all ohci drivers. Signed-off-by: Manjunath Goudar <manjunath.goudar@linaro.org> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-28USB: remove CONFIG_USB_SUSPEND optionAlan Stern1-6/+0
This patch (as1675) removes the CONFIG_USB_SUSPEND option, essentially replacing it everywhere with CONFIG_PM_RUNTIME (except for one place in hub.c, where it is replaced with CONFIG_PM because the code needs to be used in both runtime and system PM). The net result is code shrinkage and simplification. There's very little point in keeping CONFIG_USB_SUSPEND because almost everybody enables it. The few that don't will find that the usbcore module has gotten somewhat bigger and they will have to take active measures if they want to prevent hubs from being runtime suspended. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: Peter Chen <peter.chen@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-22USB: ohci: merge ohci_finish_controller_resume with ohci_resumeFlorian Fainelli1-42/+0
Merge ohci_finish_controller_resume with ohci_resume as suggested by Alan Stern. Since ohci_finish_controller_resume no longer exists, update the various OHCI drivers to call ohci_resume() instead. Some drivers used to set themselves the bit HCD_FLAG_HW_ACCESSIBLE, which is now handled by ohci_resume(). Acked-by: Jingoo Han <jg1.han@samsung.com> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Florian Fainelli <florian@openwrt.org> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-14USB: ohci-hub: Mark ohci_finish_controller_resume() as __maybe_unusedRoland Stigge1-1/+1
ohci_finish_controller_resume() is intended to be used in platform specific drivers ohci-*.c, included from ohci-hcd.c. Some of them don't actually use ohci_finish_controller_resume(), so mark it as __maybe_unused. Signed-off-by: Roland Stigge <stigge@antcom.de> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2011-11-18OHCI: remove uses of hcd->stateAlan Stern1-4/+3
This patch (as1500) removes all uses of the objectionable hcd->state variable from the ohci-hcd family of drivers. It is replaced by a private ohci->rh_state field, just as in uhci-hcd and ehci-hcd. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-19USB: Fix runtime wakeup on OHCIMatthew Garrett1-4/+1
At least some OHCI hardware (such as the MCP89) fails to flag any change in the host status register or the port status registers when receiving a remote wakeup while in D3 state. This results in the controller being resumed but no device state change being noticed, at which point the controller is put back to sleep again. Since there doesn't seem to be any reliable way to identify the state change, just unconditionally resume the hub. It'll be put back to sleep in the near future anyway if there are no active devices attached to it. Signed-off-by: Matthew Garrett <mjg@redhat.com> Cc: stable <stable@vger.kernel.org> Cc: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-14USB 3.0 Hub ChangesJohn Youn1-5/+6
Update the USB core to deal with USB 3.0 hubs. These hubs have a slightly different hub descriptor than USB 2.0 hubs, with a fixed (rather than variable length) size. Change the USB core's hub descriptor to have a union for the last fields that differ. Change the host controller drivers that access those last fields (DeviceRemovable and PortPowerCtrlMask) to use the union. Translate the new version of the hub port status field into the old version that khubd understands. (Note: we need to fix it to translate the roothub's port status once we stop converting it to USB 2.0 hub status internally.) Add new code to handle link state change status. Send out new control messages that are needed for USB 3.0 hubs, like Set Hub Depth. This patch is a modified version of the original patch submitted by John Youn. It's updated to reflect the removal of the "bitmap" #define, and change the hub descriptor accesses of a couple new host controller drivers. Signed-off-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com> Cc: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> Cc: Tony Olech <tony.olech@elandigitalsystems.com> Cc: "Robert P. J. Day" <rpjday@crashcourse.ca> Cc: Max Vozeler <mvz@vozeler.com> Cc: Tejun Heo <tj@kernel.org> Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Cc: Rodolfo Giometti <giometti@linux.it> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Anton Vorontsov <avorontsov@mvista.com> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Lothar Wassmann <LW@KARO-electronics.de> Cc: Olav Kongas <ok@artecdesign.ee> Cc: Martin Fuzzey <mfuzzey@gmail.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: David Brownell <dbrownell@users.sourceforge.net>
2011-03-14USB: Remove bitmap #define from hcd.hSarah Sharp1-6/+6
Using a #define to redefine a common variable name is a bad thing, especially when the #define is in a header. include/linux/usb/hcd.h redefined bitmap to DeviceRemovable to avoid typing a long field in the hub descriptor. This has unintended side effects for files like drivers/usb/core/devio.c that include that file, since another header included after hcd.h has different variables named bitmap. Remove the bitmap #define and replace instances of it in the host controller code. Cleanup the spaces around function calls and square brackets while we're at it. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com> Cc: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> Cc: Tony Olech <tony.olech@elandigitalsystems.com> Cc: "Robert P. J. Day" <rpjday@crashcourse.ca> Cc: Max Vozeler <mvz@vozeler.com> Cc: Tejun Heo <tj@kernel.org> Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Cc: Rodolfo Giometti <giometti@linux.it> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Anton Vorontsov <avorontsov@mvista.com> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Lothar Wassmann <LW@KARO-electronics.de> Cc: Olav Kongas <ok@artecdesign.ee> Cc: Martin Fuzzey <mfuzzey@gmail.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: David Brownell <dbrownell@users.sourceforge.net>
2010-08-11USB: controller resume should check the root hubAlan Stern1-1/+6
This patch (as1394) adds code to ehci-hcd, ohci-hcd, and uhci-hcd for automatically resuming the root hub when the controller is resumed, if the root hub has a wakeup request pending on some port. During resume from system sleep this doesn't matter, because the root hubs will naturally be resumed along with every other device in the system. However it _will_ matter for runtime PM: If the controller is suspended and a remote wakeup request is received then the controller will autoresume, but we need to ensure that the root hub also autoresumes. Otherwise the wakeup request would be ignored, the controller would go back to sleep, and the cycle would repeat a large number of times (I saw this happen before the patch was written). Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-11USB: convert usb_hcd bitfields into atomic flagsAlan Stern1-6/+10
This patch (as1393) converts several of the single-bit fields in struct usb_hcd to atomic flags. This is for safety's sake; not all CPUs can update bitfield values atomically, and these flags are used in multiple contexts. The flag fields that are set only during registration or removal can remain as they are, since non-atomic accesses at those times will not cause any problems. (Strictly speaking, the authorized_default flag should become atomic as well. I didn't bother with it because it gets changed only via sysfs. It can be done later, if anyone wants.) Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-30USB: OHCI: don't look at the root hub to get the number of portsAlan Stern1-1/+1
This patch (as1371) fixes a small bug in ohci-hcd. The HCD already knows how many ports the controller has; there's no need to go looking at the root hub's usb_device structure to find out. Especially since the root hub's maxchild value is set correctly only while the root hub is bound to the hub driver. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-18USB: OHCI: fix endless polling behaviorAlan Stern1-19/+32
This patch (as1149) fixes an obscure problem in OHCI polling. In the current code, if the RHSC interrupt status flag turns on at a time when RHSC interrupts are disabled, it will remain on forever: The interrupt handler is the only place where RHSC status gets turned back off; The interrupt handler won't turn RHSC status off because it doesn't turn off status flags if the corresponding interrupt isn't enabled; RHSC interrupts will never get enabled because ohci_root_hub_state_changes() doesn't reenable RHSC if RHSC status is on! As a result we will continue polling indefinitely instead of reverting to interrupt-driven operation, and the root hub will not autosuspend. This particular sequence of events is not at all unusual; in fact plugging a USB device into an OHCI controller will usually cause it to occur. Of course, this is a bug. The proper thing to do is to turn off RHSC status just before reading the actual port status values. That way either a port status change will be detected (if it occurs before the status read) or it will turn RHSC back on. Possibly both, but that won't hurt anything. We can still check for systems in which RHSC is totally broken, by re-reading RHSC after clearing it and before reading the port statuses. (This re-read has to be done anyway, to post the earlier write.) If RHSC is on but no port-change statuses are set, then we know that RHSC is broken and we can avoid re-enabling it. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-18OHCI: Allow broken controllers to auto-stopAlan Stern1-28/+32
This patch (as1134) attempts to improve the way we handle OHCI controllers with broken Root Hub Status Change interrupt support. In these controllers the RHSC interrupt bit essentially never turns off, making RHSC interrupts useless -- they have to remain permanently disabled. Such controllers should still be allowed to turn off their root hubs when no devices are attached. Polling for new connections can continue while the root hub is suspended. The patch implements this feature. (It won't have much effect unless CONFIG_PM is enabled and CONFIG_USB_SUSPEND is disabled, but since the overhead is very small we may as well do it.) Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-21USB: automatically enable RHSC interruptsAlan Stern1-22/+31
This patch (as1069c) changes the way OHCI root-hub status-change interrupts are enabled. Currently a special HCD method, hub_irq_enable(), is called when the hub driver is finished using a root hub. This approach turns out to be subject to races, resulting in unnecessary polling. The patch does away with the method entirely. Instead, the driver automatically enables the RHSC interrupt when no more status changes are present. This scheme is safe with controllers using level-triggered semantics for their interrupt flags. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-14USB: Hook start_hnp into ohci structDmitry Baryshkov1-3/+1
Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-14USB: OHCI: fix system hang caused by earlier patchAlan Stern1-0/+7
This patch (as1114) fixes a problem that was revealed by an earlier patch (as1069b). Some broken controllers seem never to turn off their RHCS interrupt status bit, even when told to do so. As a result they generate an interrupt storm and hang the system. The patch avoids enabling RHSC interrupt requests when the RHCS status bit is already set. This should have no adverse affects on normal controllers, since they won't set the status bit until a root-hub status change actually occurs, in which case we wouldn't enable RHSC interrupt requests anyway -- we would wait until the status change had been processed and cleared. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested by: Andrey Borzenkov <arvidjaar@mail.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-06Revert "USB: don't explicitly reenable root-hub status interrupts"Linus Torvalds1-31/+22
This reverts commit e872154921a6b5256a3c412dd69158ac0b135176. Andrey Borzenkov reports that it resulted in a totally hung machine for him when loading the OHCI driver. Extensive netconsole capture with SysRq output shows that modprobe gets stuck in ohci_hub_status_data() when probing and enabling the OHCI controller, see for example http://lkml.org/lkml/2008/7/5/236 for an analysis. The problem appears to be an interrupt flood triggered by the commit that gets reverted, and Andrey confirmed that the revert makes things work for him again. Reported-and-tested-by: Andrey Borzenkov <arvidjaar@mail.ru> Acked-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: David Brownell <david-b@pacbell.net> Cc: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-02USB: OHCI: work around bogus compiler warningAlan Stern1-1/+1
The patch (as1086) works around a bogus "uninitialized variable" warning generated by some versions of GCC. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-29usb: use get/put_unaligned_* helpersHarvey Harrison1-2/+2
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-25USB: don't explicitly reenable root-hub status interruptsAlan Stern1-22/+31
This patch (as1069b) changes the way OHCI root-hub status-change interrupts are enabled. Currently a special HCD method, hub_irq_enable(), is called when the hub driver is finished using a root hub. This approach turns out to be subject to races, resulting in unnecessary polling. The patch does away with the method entirely. Instead, the driver automatically enables the RHSC interrupt when no more status changes are present. This scheme is safe with controllers using level-triggered semantics for their interrupt flags. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-25USB: OHCI: turn off RD when remote wakeup is disabledAlan Stern1-1/+2
This patch (as1068b) disables the RD interrupt flag when an OHCI root hub is suspended with remote wakeup disabled. Although the spec clearly states that this flag permits the controller to issue an interrupt when a resume request from downstream is detected and not when a local status change occurs, some controllers mistakenly use it for both types of event. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-25USB: HCDs use the do_remote_wakeup flagAlan Stern1-3/+2
When a USB device is suspended, whether or not it is enabled for remote wakeup depends on the device_may_wakeup() setting. The setting is then saved in the do_remote_wakeup flag. Later on, however, the device_may_wakeup() value can change because of user activity. So when testing whether a suspended device is or should be enabled for remote wakeup, we should always test do_remote_wakeup instead of device_may_wakeup(). This patch (as1076) makes that change for root hubs in several places. The patch also adjusts uhci-hcd so that when an autostopped controller is suspended, the remote wakeup setting agrees with the value recorded in the root hub's do_remote_wakeup flag. And the patch adjusts ehci-hcd so that wakeup events on selectively suspended ports (i.e., the bus itself isn't suspended) don't turn on the PME# wakeup signal. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-25USB: OHCI: host-controller resumes leave root hub suspendedAlan Stern1-0/+43
Drivers in the ohci-hcd family should perform certain tasks whenever their controller device is resumed. These include checking for loss of power during suspend, turning on port power, and enabling interrupt requests. Until now these jobs have been carried out when the root hub is resumed, not when the controller is. Many drivers work around the resulting awkwardness by automatically resuming their root hub whenever the controller is resumed. But this is wasteful and unnecessary. To simplify the situation, this patch (as1066) adds a new core routine, ohci_finish_controller_resume(), which can be used by all the OHCI-variant drivers. They can call the new routine instead of resuming their root hubs. And ohci-pci.c can call it instead of using its own special-purpose handler. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-25USB: ohci: port reset paranoia timeoutDavid Brownell1-3/+21
This limits how long the OHCI port reset loop waits for the hardware to do its job, if the controller either (a) dies, or (b) can't finish the reset. Such limits are always a good idea. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-13USB: Fix NEC OHCI chip silicon bugMichael Hanselmann1-2/+3
This patch fixes a silicon bug in some NEC OHCI chips. The bug appears at random times and is very, very difficult to reproduce. Without the following patch, Linux would shut the chip and its associated devices down. In Apple PowerBooks this leads to an unusable keyboard and mouse (SSH still working). The idea of restarting the chip is taken from public Darwin code. Signed-off-by: Michael Hanselmann <linux-kernel@hansmi.ch> Cc: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-09OHCI: Fix machine check in ohci_hub_status_dataAlan Stern1-0/+2
This patch (as901) fixes an oversight in ohci-hcd. The hub_status_data routine must not try to access the controller's memory-mapped registers if the controller is in a low-power state; such attempts will cause a crash on some architectures (such as PPC). Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-20USB: ohci handles hardware faults during root port resetsTakamasa Ohtake1-2/+7
I have found a problem where the root_port_reset() goes into an infinite loop and stalls the kernel. This happens when a hardware fault inside the machine occurs during a small timing window. In case of USB device connection, if a USB device responds to hcd_submit_urb(), and later the controller fails before root_port_reset(), root_port_reset() will loop infinitely because ohci_readl() will always return "-1". Such a failure can include ejecting a CardBus OHCI controller. The probability of this problem is low, but it will increase if PnP type usage is frequent. The attached patch can solve this problem and I believe that it is better to fix this problem. Signed-off-by: Takamasa Ohtake <ohtake-txa@necst.nec.co.jp> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-20USB: ohci whitespace/comment fixupsDavid Brownell1-6/+6
This is an OHCI cleanup patch ... it removes a lot of erroneous whitespace (space before tab, at end of line) as well as the obsolete inline changelog. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-02OHCI: make autostop conditional on CONFIG_PMAlan Stern1-54/+79
Unlike UHCI, OHCI does not exert any DMA load on the system when no devices are connected. Consequently there is no advantage to doing an autostop other than the power savings, so we shouldn't compile the necessary code unless CONFIG_PM is enabled. This patch (as820) makes the root-hub suspend and resume routines conditional on CONFIG_PM. It also prevents autostop from activating if the device_may_wakeup flag isn't set; some people use this flag to alert the driver about Resume-Detect bugs in the hardware. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-02OHCI: change priority level of resume log messageAlan Stern1-1/+1
All the other root-hub suspend or resume log messages, in ohci-hcd or any of the other host controller drivers, use the debug priority level. This patch (as815) makes the one single exception behave like all the rest. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-02USB: OHCI: remove stale testing code from root-hub resumeAlan Stern1-12/+1
This patch (as811) removes some stale testing code from the root-hub resume routine in ohci-hcd. It also adds a spin_lock_irq() call that inadvertently got left out of an error pathway. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-02USB: OHCI: disable RHSC inside interrupt handlerAlan Stern1-16/+8
This patch (as808b) moves the Root Hub Status Change interrupt-disable code in ohci-hcd back into the interrupt handler proper, to avoid the chance of adverse interactions with mediocre hardware implementations. It also deletes the root-hub status timer from within the interrupt-enable routine. There's no need to poll for status any more once interrupts are re-enabled. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-02USB: ohci-hcd: fix compiler warningAlan Stern1-2/+4
This patch (as806) fixes a compiler warning when ohci-hcd is built with CONFIG_PM turned off. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-11-17USB: OHCI: fix root-hub resume bugAlan Stern1-1/+2
When a suspended OHCI controller sees a port's status change, it sets both the Root-Hub-Status-Change and the Resume-Detect bits in the Interrupt Status register. Processing both these bits, the driver tries to resume the root hub twice! This patch (as807) fixes the bug by ignoring RD if RHSC is set. It also prints a slightly more informative log message when a remote-wakeup event occurs. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>