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path: root/drivers/usb/host/ehci.h
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2016-12-05fsl/usb: Workarourd for USB erratum-A005697Changming Huang1-0/+8
The EHCI specification states the following in the SUSP bit description: In the Suspend state, the port is sensitive to resume detection. Note that the bit status does not change until the port is suspended and that there may be a delay in suspending a port if there is a transaction currently in progress on the USB. However, in NXP USBDR controller, the PORTSCx[SUSP] bit changes immediately when the application sets it and not when the port is actually suspended. So the application must wait for at least 10 milliseconds after a port indicates that it is suspended, to make sure this port has entered suspended state before initiating this port resume using the Force Port Resume bit. This bit is for NXP controller, not EHCI compatible. Signed-off-by: Changming Huang <jerry.huang@nxp.com> Signed-off-by: Ramneek Mehresh <ramneek.mehresh@nxp.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03usb: host: unhide suspend/resume declarationsArnd Bergmann1-2/+0
There is no need to hide function declarations, and making these visible to the SoC specific host drivers lets us use __maybe_unused and IS_ENABLED() checks to control their use, rather than having to use #ifdef to hide all callers. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-03usb: ehci: remove old stub_debug_files definitionGeyslan G. Bem1-5/+0
This patch removes the local STUB_DEBUG_FILES debugging definition. STUB_DEBUG_FILES was used only in ehci-hcd, whereas CONFIG_DYNAMIC_DEBUG is used all over the kernel. Signed-off-by: Geyslan G. Bem <geyslan@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-03usb: host: ehci.h: move constant to rightGeyslan G. Bem1-1/+1
This patch moves the constant 0x3ff to right and put spaces in the right shift. Caught by coccinelle: scripts/coccinelle/misc/compare_const_fl.cocci Signed-off-by: Geyslan G. Bem <geyslan@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-03usb: host: ehci.h: move pointer operator to name sideGeyslan G. Bem1-1/+1
The pointer operator must be sticked to name. Caught by checkpatch: ERROR: "foo * bar" should be "foo *bar" Signed-off-by: Geyslan G. Bem <geyslan@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-03usb: host: ehci.h: remove macros trailing semicolonGeyslan G. Bem1-2/+2
Removes trailing semicolon from macros. Caught by checkpatch: "WARNING: macros should not use a trailing semicolon" Signed-off-by: Geyslan G. Bem <geyslan@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-03usb: host: ehci.h: use space after commaGeyslan G. Bem1-2/+3
Put space after comma. This patch also changes QH_NEXT macro for better reading. Caught by checkpatch: "ERROR: space required after that ','" Signed-off-by: Geyslan G. Bem <geyslan@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-03usb: host: ehci.h: remove direct use of __attribute__ keywordGeyslan G. Bem1-5/+5
Prefer to use __aligned(size) macro instead of __attribute__((aligned(size))). Caught by checkpatch. Signed-off-by: Geyslan G. Bem <geyslan@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-03usb: host: ehci.h: fix single statement macrosGeyslan G. Bem1-2/+2
Don't use the 'do {} while (0)' wrapper in a single statement macro. Caught by checkpatch: "WARNING: Single statement macros should not use a do {} while (0) loop" Signed-off-by: Geyslan G. Bem <geyslan@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-03usb: host: ehci.h: remove space before open square bracketGeyslan G. Bem1-11/+11
Get rid of space before open square bracket. Caught by checkpatch: "ERROR: space prohibited before open square bracket '['" Signed-off-by: Geyslan G. Bem <geyslan@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-03usb: host: ehci.h: remove space before function open parenthesisGeyslan G. Bem1-11/+11
Get rid of space between function name and open parenthesis. Caught by checkpatch: "WARNING: space prohibited between function name and open parenthesis '('" Signed-off-by: Geyslan G. Bem <geyslan@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-03usb: host: ehci.h: remove space before commaGeyslan G. Bem1-4/+4
Get rid of spaces before comma. Caught by checkpatch: "ERROR: space prohibited before that ','" Signed-off-by: Geyslan G. Bem <geyslan@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-03USB: EHCI: add a delay when unlinking an active QHAlan Stern1-0/+3
Michael Reutman reports that an AMD/ATI EHCI host controller on one of his computers does not stop transferring data when an active bulk QH is unlinked from the async schedule. Apparently that host controller fails to implement the IAA mechanism correctly when an active QH is unlinked. This leads to data corruption, because the controller continues to update the QH in memory when the driver doesn't expect it. As a result, the next URB submitted for that QH can hang, because the link pointers for the TD queue have been messed up. This misbehavior is observed quite regularly. To be fair, the EHCI spec (section 4.8.2) says that active QHs should not be unlinked. It goes on to recommend a procedure that involves waiting for the QH to go inactive before unlinking it. In the real world this is impractical, not least because the QH may _never_ go inactive. (What were they thinking?) Sometimes we have no choice but to unlink an active QH. In an attempt to avoid the problems that can ensue, this patch changes how the driver decides when the unlink is complete. In addition to waiting through two IAA cycles, in cases where the QH was not known to be inactive beforehand we now wait until a 2-ms period has elapsed with the host controller making no change to the QH data structure (the hw_current and hw_token fields in particular). The intuition here is that after such a long period, the endpoint must be NAKing and hopefully the QH has been dropped from the host controller's internal cache. There's no way to know if this reasoning is really valid -- the spec is no help in this regard -- but at least this approach fixes Michael's problem. The test for whether the QH is already known to be inactive involves the reason for unlinking the QH originally. If it was unlinked because it had halted, or it stopped in response to a short read, or it overlaid a dummy TD (a silicon bug), then it certainly is inactive. If it was unlinked because the TD queue was empty and no TDs have been added to the queue in the meantime, then it must be inactive. Or if the hardware status indicates that the QH is currently halted (even if that wasn't the reason for unlinking it), then it is inactive. Otherwise, if none of those checks apply, we go through the 2-ms delay. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Michael Reutman <mreutman@epiqsolutions.com> Tested-by: Michael Reutman <mreutman@epiqsolutions.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-03USB: EHCI: store reason for unlinking a QHAlan Stern1-2/+8
This patch replaces the "exception" bitflag in the ehci_qh structure with a more explicit "unlink_reason" bitmask. This is for use in the following patch, where we will need to have a good idea of the reason for unlinking a QH, not just "something exceptional happened". Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Michael Reutman <mreutman@epiqsolutions.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-01USB: EHCI: warn on unexpectedly active QHAlan Stern1-0/+1
This patch adds a new warning message to ehci-hcd. The warning is triggered whenever the driver finds that the hardware has set the Active bit in a QH at a time when the driver expects the QH to be completely idle. Such bugs have been observed by users in the past, and since they can lead to serious problems (such as inability to unlink an URB that never completes), it would be good to know about them when they occur. This won't fix these bugs; that's a bigger job for a later patch. But success isn't guaranteed, since this depends on aspects of the hardware which are not documented in the EHCI spec or for which the spec's recommendations are clearly unworkable. It therefore seems worthwhile to check for these bugs proactively. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Michael Reutman <mreutman@epiqsolutions.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-14drivers: usb: fsl: Workaround for USB erratum-A005275Nikhil Badola1-0/+12
Incoming packets in high speed are randomly corrupted by h/w resulting in multiple errors. This workaround makes FS as default mode in all affected socs by disabling HS chirp signalling.This errata does not affect FS and LS mode. Forces all HS devices to connect in FS mode for all socs affected by this erratum: P3041 and P2041 rev 1.0 and 1.1 P5020 and P5010 rev 1.0 and 2.0 P5040, P1010 and T4240 rev 1.0 Signed-off-by: Ramneek Mehresh <ramneek.mehresh@freescale.com> Signed-off-by: Nikhil Badola <nikhil.badola@freescale.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-31drivers:usb:fsl: Fix compilation error for fsl ehci drvRamneek Mehresh1-0/+3
Fix compilation error in fsl ehci drv because ehci_reset() and ehci_adjust_port_wakeup_flags() were not exported, and are used when PM is enabled Signed-off-by: Ramneek Mehresh <ramneek.mehresh@freescale.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09USB: ehci-platform: Support ehci reset after resume quirkWu Liang feng1-1/+1
The Rockchip rk3288 EHCI controller doesn't properly detect the case when a device is removed during suspend. Specifically, when usb resume from suspend, the EHCI controller maintaining the USB state (FLAG_CF is 1, Current Connect Status is 1), but a USB device (like a USB camera on rk3288) may have been disconnected actually. Let's add a quirk to force ehci to go into the usb_root_hub_lost_power() path and reset after resume. This should generally reset the whole controller and all ports and initialize everything cleanly again, and bring the devices back up. As part of this, rename the "hibernation" paramter of ehci_resume() to force_reset since hibernation is simply another case where we can't trust the autodetected status and need to force a reset of devices. Signed-off-by: Wu Liang feng <wulf@rock-chips.com> Reviewed-by: Julius Werner <jwerner@google.com> Reviewed-by: Doug Anderson <dianders@google.com> Reviewed-by: Tomasz Figa <tfiga@google.com> Reviewed-by: Pawel Osciak <posciak@google.com> Reviewed-by: Sonny Rao <sonnyrao@google.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Doug Anderson <dianders@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-03usb: ehci: add ehci_port_power interfaceMichael Grzeschik1-0/+2
The current EHCI implementation is prepared to toggle the PORT_POWER bit to enable or disable a USB-Port. In some cases this port power can not be just toggled by the PORT_POWER bit, and the gpio-regulator is needed to be toggled too. This patch defines a port power control interface ehci_port_power for ehci core use, it toggles PORT_POWER bit as well as calls platform defined .port_power if it is defined. Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de> Signed-off-by: Peter Chen <peter.chen@freescale.com> Acked-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-24USB: EHCI: Export the ehci_hub_control functionLaurent Pinchart1-0/+3
Platform drivers sometimes need to perform specific handling of hub control requests. Make this possible by exporting the ehci_hub_control() function which can then be called from a custom hub control handler in the default case. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-01-13usb: ehci: add freescale imx28 special write register methodPeter Chen1-1/+17
According to Freescale imx28 Errata, "ENGR119653 USB: ARM to USB register error issue", All USB register write operations must use the ARM SWP instruction. So, we implement a special ehci_write for imx28. Discussion for it at below: http://marc.info/?l=linux-usb&m=137996395529294&w=2 Without this patcheset, imx28 works unstable at high AHB bus loading. If the bus loading is not high, the imx28 usb can work well at the most of time. There is a IC errata for this problem, usually, we consider IC errata is a problem not a new feature, and this workaround is needed for that, so we need to add them to stable tree 3.11+. Cc: stable@vger.kernel.org Cc: robert.hodaszi@digi.com Signed-off-by: Peter Chen <peter.chen@freescale.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Tested-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-03usb: kill DEBUG compile optionOliver Neukum1-4/+4
In the drivers that no longer need it, it is removed. It is removed from the Makefile. Drivers not fully converted to dynamic debug have it shifted down into the individual drivers. Signed-off-by: Oliver Neukum <oneukum@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-14USB: EHCI: create per-TT bandwidth tablesAlan Stern1-0/+33
This patch continues the scheduling changes in ehci-hcd by adding a table to store the bandwidth allocation below each TT. This will speed up the scheduling code, as it will no longer need to read through the entire schedule to compute the bandwidth currently in use. Properly speaking, the FS/LS budget calculations should be done in terms of full-speed bytes per microframe, as described in the USB-2 spec. However the driver currently uses microseconds per microframe, and the scheduling code isn't robust enough at this point to change over. For the time being, we leave the calculations as they are. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11USB: EHCI: use a bandwidth-allocation tableAlan Stern1-1/+12
This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11USB: EHCI: create a "periodic schedule info" structAlan Stern1-13/+16
This patch begins the process of unifying the scheduling parameters that ehci-hcd uses for interrupt and isochronous transfers. It creates an ehci_per_sched structure, which will be stored in both ehci_qh and ehci_iso_stream structures, and will contain the common scheduling information needed for both. Initially we merely create the new structure and move some existing fields into it. Later patches will add more fields and utilize these structures in improved scheduling algorithms. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11USB: EHCI: use consistent NO_FRAME valueAlan Stern1-2/+3
ehci-hcd is inconsistent in the sentinel values it uses to indicate that no frame number has been assigned for a periodic transfer. Some places it uses NO_FRAME (defined as 65535), other places it uses -1, and elsewhere it uses 9999. This patch defines a value for NO_FRAME which can fit in a 16-bit signed integer, and changes the code to use it everywhere. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-17USB: EHCI: handle isochronous underruns with taskletsAlan Stern1-0/+1
This patch updates the iso_stream_schedule() routine in ehci-sched.c to handle cases where an underrun causes an isochronous endpoint's queue to empty out, but the client driver wants to maintain synchronization with the device (i.e., the URB_ISO_ASAP flag is not set). This could not happen until recently, when ehci-hcd switched over to completing URBs in a tasklet. (This may seem like an unlikely case to worry about, but underruns are all too common with the snd-usb-audio driver, which doesn't use URB_ISO_ASAP.) As part of the fix, some URBs may need to be given back when they are submitted. This is necessary when the URB's scheduled slots all fall before the current value of ehci->last_iso_frame, and as an optimization we do it also when the slots all fall before the current frame number. As a second part of the fix, we may need to skip some but not all of an URB's packets. This is necessary when some of the URB's scheduled slots fall before the current value of ehci->last_iso_frame and some of them fall after the current frame number. A new field (first_packet) is added to struct ehci_iso_sched, to indicate how many packets should be skipped. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-30ehci: enable debugging code when CONFIG_DYNAMIC_DEBUG is setXenia Ragiadakou1-4/+4
The debugging code for ehci is enabled to run if the DEBUG flag is defined. This patch enables the debugging code also when the kernel is configured with dynamic debugging on. Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com> Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-30ehci: remove ehci_vdbg() verbose debugging statementsXenia Ragiadakou1-5/+0
This patch removes ehci_vdbg debugging statements from EHCI host controller driver because they produce too much information, lowering the signal to noise ratio when debugging, and because they are not used anymore. Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com> Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-13Merge tag 'usb-for-v3.12' of ↵Greg Kroah-Hartman1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next Felipe writes: usb: patches for v3.12 merge window All patches here have been pending on linux-usb and sitting in linux-next for a while now. The biggest things in this tag are: DWC3 learned proper usage of threaded IRQ handlers and now we spend very little time in hardirq context. MUSB now has proper support for BeagleBone and Beaglebone Black. Tegra's USB support also got quite a bit of love and is learning to use PHY layer and generic DT attributes. Other than that, the usual pack of cleanups and non-critical fixes follow. Signed-of-by: Felipe Balbi <balbi@ti.com> Conflicts: drivers/usb/gadget/udc-core.c drivers/usb/host/ehci-tegra.c drivers/usb/musb/omap2430.c drivers/usb/musb/tusb6010.c
2013-08-12USB: EHCI: improve interrupt qh unlinkMing Lei1-0/+3
ehci-hcd currently unlinks an interrupt QH when it becomes empty, that is, after its last URB completes. This works well because in almost all cases, the completion handler for an interrupt URB resubmits the URB; therefore the QH doesn't become empty and doesn't get unlinked. When we start using tasklets for URB completion, this scheme won't work as well. The resubmission won't occur until the tasklet runs, which will be some time after the completion is queued with the tasklet. During that delay, the QH will be empty and so will be unlinked unnecessarily. To prevent this problem, this patch adds a 5-ms time delay before empty interrupt QHs are unlinked. Most often, during that time the interrupt URB will be resubmitted and thus we can avoid unlinking the QH. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12usb: host: add has_tdi_phy_lpm capability bitTuomas Tynkkynen1-0/+1
The has_hostpc capability bit indicates that the host controller has the HOSTPC register extensions, but at the same time enables clock disabling power saving features with the PHY Low Power Clock Disable (PHCD) bit. However, some host controllers have the HOSTPC extensions but don't support the low-power feature, so the PHCD bit must not be set on those controllers. Add a separate capability bit for the low-power feature instead, and change all existing users of has_hostpc to use this new capability bit. The idea for this commit is taken from an old 2012 commit that never got merged ("disociate chipidea PHY low power suspend control from hostpc") Inspired-by: Matthieu CASTET <matthieu.castet@parrot.com> Signed-off-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Stephen Warren <swarren@nvidia.com> Reviewed-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Felipe Balbi <balbi@ti.com>
2013-06-17USB: EHCI: export ehci_handshake for ehci-hcd sub-driversManjunath Goudar1-0/+2
In order to split ehci-hcd.c into separate modules, handshake() must be exported. Rename the symbol to add an ehci_ prefix, to avoid any naming clashes. Signed-off-by: Manjunath Goudar <manjunath.goudar@linaro.org> [swarren, split Manjunath's patches more logically, limit this change to export just handshake()] Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Arnd Bergmann <arnd@arndb.de> Tested-by: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-03EHCI: Quirk flag for port power handling on overcurrent.Christian Engelmayer1-0/+1
Commit 756aa6b3d536afe85e151138cb03a293998887b3 (ehci-hub: improved over-current recovery) added port power cycling on overcurrent indications as needed by the MPC8349 USB controller after resolving of the overcurrent situation in order to have the host state machine assert the correct port status again. Commit 81463c1d707186adbbe534016cd1249edeab0dac (EHCI: only power off port if over-current is active) solved a thus resulting issue of endless overcurrent changes in combination with the MAX4967 USB power supply chip that signals overcurrent when power is not enabled by only powering off a port if the overcurrent is currently active. Added quirks flag need_oc_pp_cycle in order to specify the needed behaviour as there is no common behaviour that can comply with both requirements. Activated the quirks handling for Freescale 83xx based boards. Signed-off-by: Christian Engelmayer <christian.engelmayer@frequentis.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-25USB: EHCI: improve end_unlink_async()Alan Stern1-1/+2
This patch (as1665) changes the way ehci-hcd's end_unlink_async() routine works in order to avoid recursive execution and to be more efficient: Now when an IAA cycle ends, a new one gets started up right away (if it is needed) instead of waiting until the just-unlinked QH has been processed. The async_iaa list is renamed to async_idle, which better expresses its new purpose: It is now the list of QHs which are now completely idle and are waiting to be processed by end_unlink_async(). A new flag is added to track whether an IAA cycle is in progress, because the list formerly known as async_iaa no longer stores the QHs waiting for the IAA to finish. The decision about how many QHs to process when an IAA cycle ends is now made at the end of the cycle, when we know the current state of the hardware, rather than at the beginning. This means a bunch of logic got moved from start_iaa_cycle() to end_unlink_async(). Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-25USB: EHCI: convert singly-linked lists to list_headsAlan Stern1-6/+4
This patch (as1664) converts ehci-hcd's async_unlink, async_iaa, and intr_unlink from singly-linked lists to standard doubly-linked list_heads. Originally it didn't seem necessary to use list_heads, because items are always added to and removed from these lists in FIFO order. But now with more list processing going on, it's easier to use the standard routines than continue with a roll-your-own approach. I don't know if the code ends up being notably shorter, but the patterns will be more familiar to any kernel hacker. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-25USB: EHCI: split needs_rescan into two flagsAlan Stern1-1/+3
This patch (as1662) does some more QH-related cleanup in ehci-hcd. The qh->needs_rescan flag is currently used for two different purposes; the patch replaces it with two separate flags for greater clarity: qh->dequeue_during_giveback indicates that a completion handler dequeued an URB (implying that a rescan is needed), and qh->exception indicates that the QH is in an exceptional state requiring an unlink (either it encountered an I/O error or an unlink was requested). The new flags get set where the dequeue, exception, or unlink request occurred, rather than where the unlink is started. This is so that in the future, if we need to, we will be able to tell apart unlinks that truly were required from those that were carried out merely because the QH wasn't being used. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-22USB: EHCI: add a name for the platform-private fieldAlan Stern1-0/+3
This patch (as1642) adds an ehci->priv field for private use by EHCI platform drivers. The space was provided some time ago, but it didn't have a name. Until now none of the platform drivers has used this private space, but that's about to change in the next patch of this series. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-22USB: EHCI: Move definition of EHCI_STATS to ehci.hRoger Quadros1-0/+4
Without this, platform drivers e.g. ehci-omap.c will see a different version of struct ehci_hcd than ehci-hcd.c and break reference to 'debug_dir' and 'priv' members when CONFIG_USB_DEBUG is enabled. Signed-off-by: Roger Quadros <rogerq@ti.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-11USB: EHCI: miscellaneous cleanups for the library conversionAlan Stern1-1/+0
This patch (as1630) cleans up a few minor items resulting from the split-up of the ehci-hcd driver: Remove the product_desc string from the ehci_driver_overrides structure. All drivers will use the generic "EHCI Host Controller" string. (This was requested by Felipe Balbi.) Allow drivers to pass a NULL pointer to ehci_init_driver() if they don't have to override any settings. Remove a #define symbol that is no longer used from the ChipIdea host driver. Rename overrides to pci_overrides in ehci-pci.c, for consistency with ehci-platform.c. Mark the *_overrides structures as __initdata. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reviewed-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-01USB: EHCI: prepare to make ehci-hcd a library moduleAlan Stern1-0/+17
This patch (as1624) prepares ehci-hcd for being split up into a core library and separate platform driver modules. A generic ehci_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 ehci_setup(), ehci_suspend(), and ehci_resume() routines need to be EXPORTed for use by the drivers. As a side effect of this change, a few routines no longer need to be marked __maybe_unused. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-31USB: EHCI: remove unused Link Power Management codeAlan Stern1-1/+0
This patch (as1622) removes the USB-2.1 Link Power Management code from the ehci-hcd driver. This code was never integrated with usbcore, it is full of bugs, and it was not getting used by anybody. However, the debugging code for dumping the LPM-related fields in the EHCI registers is left in place. In theory it might be useful to see these values, even though we don't use them. This essentially amounts to a partial revert of commit aa4d8342988d0c1a79ff19b2ede1e81dfbb16ea5 (USB: EHCI: EHCI 1.1 addendum: preparation) and an almost full revert of commit 48f24970144479c29b8cee6d2e1dbedf6dcf9cfb (USB: EHCI: EHCI 1.1 addendum: Basic LPM feature support) plus its follow-ons. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24USB: EHCI: make ehci_read_frame_index platform independentAlan Stern1-16/+0
In preparation for splitting the ehci-hcd driver into a core library and separate platform-specific driver modules, this patch (as1617) changes the way ehci_read_frame_index() is handled. Since the same core library will have to work with both PCI and non-PCI platforms, the quirk handler routine will be compiled unconditionally. The decision about whether to call it or simply to read the frame index register is made at run time, based on whether the frame_index_bug quirk flag is set. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24USB: EHCI: move logging macros to ehci.hAlan Stern1-0/+15
In preparation for splitting the ehci-hcd driver into a core library and separate platform-specific driver modules, this patch (as1616) moves the console logging macros from ehci-dbg.c to ehci.h, where they will be available to the platform drivers. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-22EHCI: use the isochronous scheduling thresholdAlan Stern1-1/+0
This patch (as1609) changes the way ehci-hcd uses the "Isochronous Scheduling Threshold" in its calculations. Until now the code has ignored the threshold except for certain Intel PCI-based controllers. This violates the EHCI spec. The new code takes the threshold into account always, removing the need for the fs_i_thresh quirk flag. In addition it implements the "full frame cache" setting more efficiently, moving forward only as far as the next frame boundary instead of always moving forward 8 microframes. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-22EHCI: improved logic for isochronous schedulingAlan Stern1-1/+1
This patch (as1608) reworks the logic used by ehci-hcd for scheduling isochronous transfers. Now the modular calculations are all based on a window that starts at the last frame scanned for isochronous completions. No transfer descriptors for any earlier frames can possibly remain on the schedule, so there can be no confusion from schedule wrap-around. This removes the need for a "slop" region of arbitrary size. There's no need to check for URBs that are longer than the schedule length. With the old code they could throw things off by wrapping around and appearing to end in the near future rather than the distant future. Now such confusion isn't possible, and the existing test for submissions that extend too far into the future will also catch those that exceed the schedule length. (But there still has to be an initial test to handle the case where the schedule already extends as far into the future as possible.) Delays caused by IRQ latency won't confuse the algorithm unless they are ridiculously long (over 250 ms); they will merely reduce how far into the future new transfers can be scheduled. A few people have reported problems caused by delays of 50 ms or so. Now instead of failing completely, isochronous transfers will experience a brief glitch and then continue normally. (Whether this is truly a good thing is debatable. A latency as large as 50 ms generally indicates a bug is present, and complete failure of audio or video transfers draws people's attention pretty vividly. Making the transfers more robust also makes it easier for such bugs to remain undetected.) Finally, ehci->next_frame is renamed to ehci->last_iso_frame, because that better describes what it is: the last frame to have been scanned for isochronous completions. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16USB: EHCI: resolve some unlikely racesAlan Stern1-0/+1
This patch (as1589) resolves some unlikely races involving system shutdown or controller death in ehci-hcd: Shutdown races with both root-hub resume and controller resume. Controller death races with root-hub suspend. A new bitflag is added to indicate that the controller has been shut down (whether for system shutdown or because it died). Tests are added in the suspend and resume pathways to avoid reactivating the controller after any sort of shutdown. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16USB: EHCI: simplify isochronous scanningAlan Stern1-3/+3
This patch (as1587) simplifies ehci-hcd's scan_isoc() routine by eliminating some local variables, declaring boolean-valued values as bool rather than unsigned, changing variable names to make more sense, and so on. The logic at the end of the routine is cut down significantly. The scanning doesn't have to catch up all the way to where the hardware is; it merely has to catch up to where the hardware was when the last interrupt occurred. If the hardware has made more progress since then and issued another interrupt, a rescan will catch up to it. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16USB: EHCI: use hrtimer for the I/O watchdogAlan Stern1-12/+1
This patch (as1586) replaces the kernel timer used by ehci-hcd as an I/O watchdog with an hrtimer event. Unlike in the current code, the watchdog event is now always enabled whenever any isochronous URBs are active. This will prevent bugs caused by the periodic schedule wrapping around with no completion interrupts; the watchdog handler is guaranteed to scan the isochronous transfers at least once during each iteration of the schedule. The extra overhead will be negligible: one timer interrupt every 100 ms. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16USB: EHCI: always scan each interrupt QHAlan Stern1-3/+5
This patch (as1585) fixes a bug in ehci-hcd's scheme for scanning interrupt QHs. Currently a single routine takes care of scanning everything on the periodic schedule. Whenever an interrupt occurs, it scans all isochronous and interrupt URBs scheduled for frames that have elapsed since the last scan. This has two disadvantages. The first is relatively minor: An interrupt QH is likely to end up getting scanned multiple times, particularly if the last scan was not fairly recent. (The current code avoids this by maintaining a periodic_stamp in each interrupt QH.) The second is more serious. The periodic schedule wraps around. If the last scan occurred during frame N, and the next scan occurs when the schedule has gone through an entire cycle and is back at frame N, the scanning code won't look at any frames other than N. Consequently it won't see any QHs that completed during frame N-1 or earlier. The patch replaces the entire frame-based approach for scanning interrupt QHs with a new routine using a list-based approach, the same as for async QHs. This has a slight disadvantage, because it means that all interrupt QHs have to be scanned every time. But it is more robust than the current approach. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>