An attack has become available which pretends to be a quirky
device circumventing normal sanity checks and crashes the kernel
by an insufficient number of interfaces. This patch adds a check
to the code path for quirky devices.
Signed-off-by: NOliver Neukum <ONeukum@suse.com>
CC: stable@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Attacks that trick drivers into passing a NULL pointer
to usb_driver_claim_interface() using forged descriptors are
known. This thwarts them by sanity checking.
Signed-off-by: NOliver Neukum <ONeukum@suse.com>
CC: stable@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

With commit 69bec725 ("USB: core: let USB device know device node"),
the port1 argument of usb_alloc_dev() gets overwritten as follows:

  ... usb_alloc_dev(..., unsigned port1)
  {
    ...
    if (!parent->parent) {
      port1 = usb_hcd_find_raw_port_number(..., port1);
    }
    ...
  }

Later on, this now overwritten port1 gets assigned to ->portnum:

  dev->portnum = port1;

However, since xhci_find_raw_port_number() isn't idempotent, the
aforementioned commit causes a number of KASAN splats like the following:

  BUG: KASAN: slab-out-of-bounds in xhci_find_raw_port_number+0x98/0x170
                                       at addr ffff8801d9311670
  Read of size 8 by task kworker/2:1/87
  [...]
  Workqueue: usb_hub_wq hub_event
   0000000000000188 000000005814b877 ffff8800cba17588 ffffffff8191447e
   0000000041b58ab3 ffffffff82a03209 ffffffff819143a2 ffffffff82a252f4
   ffff8801d93115e0 0000000000000188 ffff8801d9311628 ffff8800cba17588
  Call Trace:
   [<ffffffff8191447e>] dump_stack+0xdc/0x15e
   [<ffffffff819143a2>] ? _atomic_dec_and_lock+0xa2/0xa2
   [<ffffffff814e2cd1>] ? print_section+0x61/0xb0
   [<ffffffff814e4939>] print_trailer+0x179/0x2c0
   [<ffffffff814f0d84>] object_err+0x34/0x40
   [<ffffffff814f4388>] kasan_report_error+0x2f8/0x8b0
   [<ffffffff814eb91e>] ? __slab_alloc+0x5e/0x90
   [<ffffffff812178c0>] ? __lock_is_held+0x90/0x130
   [<ffffffff814f5091>] kasan_report+0x71/0xa0
   [<ffffffff814ec082>] ? kmem_cache_alloc_trace+0x212/0x560
   [<ffffffff81d99468>] ? xhci_find_raw_port_number+0x98/0x170
   [<ffffffff814f33d4>] __asan_load8+0x64/0x70
   [<ffffffff81d99468>] xhci_find_raw_port_number+0x98/0x170
   [<ffffffff81db0105>] xhci_setup_addressable_virt_dev+0x235/0xa10
   [<ffffffff81d9ea51>] xhci_setup_device+0x3c1/0x1430
   [<ffffffff8121cddd>] ? trace_hardirqs_on+0xd/0x10
   [<ffffffff81d9fac0>] ? xhci_setup_device+0x1430/0x1430
   [<ffffffff81d9fad3>] xhci_address_device+0x13/0x20
   [<ffffffff81d2081a>] hub_port_init+0x55a/0x1550
   [<ffffffff81d28705>] hub_event+0xef5/0x24d0
   [<ffffffff81d27810>] ? hub_port_debounce+0x2f0/0x2f0
   [<ffffffff8195e1ee>] ? debug_object_deactivate+0x1be/0x270
   [<ffffffff81210203>] ? print_rt_rq+0x53/0x2d0
   [<ffffffff8121657d>] ? trace_hardirqs_off+0xd/0x10
   [<ffffffff8226acfb>] ? _raw_spin_unlock_irqrestore+0x5b/0x60
   [<ffffffff81250000>] ? irq_domain_set_hwirq_and_chip+0x30/0xb0
   [<ffffffff81256339>] ? debug_lockdep_rcu_enabled+0x39/0x40
   [<ffffffff812178c0>] ? __lock_is_held+0x90/0x130
   [<ffffffff81196877>] process_one_work+0x567/0xec0
  [...]

Afterwards, xhci reports some functional errors:

  xhci_hcd 0000:00:14.0: ERROR: unexpected setup address command completion
                                code 0x11.
  xhci_hcd 0000:00:14.0: ERROR: unexpected setup address command completion
                                code 0x11.
  usb 4-3: device not accepting address 2, error -22

Fix this by not overwriting the port1 argument in usb_alloc_dev(), but
storing the raw port number as required by OF in an additional variable,
raw_port.

Fixes: 69bec725 ("USB: core: let USB device know device node")
Signed-off-by: NNicolai Stange <nicstange@gmail.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The iowarrior driver expects at least one valid endpoint.  If given
malicious descriptors that specify 0 for the number of endpoints,
it will crash in the probe function.  Ensure there is at least
one endpoint on the interface before using it.

The full report of this issue can be found here:
http://seclists.org/bugtraq/2016/Mar/87Reported-by: NRalf Spenneberg <ralf@spenneberg.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NJosh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

PCI-SIG has defined Interface FEh for Base Class 0Ch, Sub-Class 03h as "USB
Device (not host controller)".  It is already being used in various USB
device controller drivers for matching, so add PCI_CLASS_SERIAL_USB_DEVICE
and use it.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Although most of USB devices are hot-plug's, there are still some devices
are hard wired on the board, eg, for HSIC and SSIC interface USB devices.
If these kinds of USB devices are multiple functions, and they can supply
other interfaces like i2c, gpios for other devices, we may need to
describe these at device tree.

In this commit, it uses "reg" in dts as physical port number to match
the phyiscal port number decided by USB core, if they are the same,
then the device node is for the device we are creating for USB core.
Signed-off-by: NPeter Chen <peter.chen@freescale.com>
Acked-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NRob Herring <robh@kernel.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The new USBDEVFS_DROP_PRIVILEGES ioctl allows a process to voluntarily
relinquish the ability to issue other ioctls that may interfere with
other processes and drivers that have claimed an interface on the
device.

This commit also includes a simple utility to be able to test the
ioctl, located at Documentation/usb/usbdevfs-drop-permissions.c

Example (with qemu-kvm's input device):

    $ lsusb
    ...
    Bus 001 Device 002: ID 0627:0001 Adomax Technology Co., Ltd

    $ usb-devices
    ...
    C:  #Ifs= 1 Cfg#= 1 Atr=a0 MxPwr=100mA
    I:  If#= 0 Alt= 0 #EPs= 1 Cls=03(HID  ) Sub=00 Prot=02 Driver=usbhid

    $ sudo ./usbdevfs-drop-permissions /dev/bus/usb/001/002
    OK: privileges dropped!
    Available options:
    [0] Exit now
    [1] Reset device. Should fail if device is in use
    [2] Claim 4 interfaces. Should succeed where not in use
    [3] Narrow interface permission mask
    Which option shall I run?: 1
    ERROR: USBDEVFS_RESET failed! (1 - Operation not permitted)
    Which test shall I run next?: 2
    ERROR claiming if 0 (1 - Operation not permitted)
    ERROR claiming if 1 (1 - Operation not permitted)
    ERROR claiming if 2 (1 - Operation not permitted)
    ERROR claiming if 3 (1 - Operation not permitted)
    Which test shall I run next?: 0

After unbinding usbhid:

    $ usb-devices
    ...
    I:  If#= 0 Alt= 0 #EPs= 1 Cls=03(HID  ) Sub=00 Prot=02 Driver=(none)

    $ sudo ./usbdevfs-drop-permissions /dev/bus/usb/001/002
    ...
    Which option shall I run?: 2
    OK: claimed if 0
    ERROR claiming if 1 (1 - Operation not permitted)
    ERROR claiming if 2 (1 - Operation not permitted)
    ERROR claiming if 3 (1 - Operation not permitted)
    Which test shall I run next?: 1
    OK: USBDEVFS_RESET succeeded
    Which test shall I run next?: 0

After unbinding usbhid and restricting the mask:

    $ sudo ./usbdevfs-drop-permissions /dev/bus/usb/001/002
    ...
    Which option shall I run?: 3
    Insert new mask: 0
    OK: privileges dropped!
    Which test shall I run next?: 2
    ERROR claiming if 0 (1 - Operation not permitted)
    ERROR claiming if 1 (1 - Operation not permitted)
    ERROR claiming if 2 (1 - Operation not permitted)
    ERROR claiming if 3 (1 - Operation not permitted)
Signed-off-by: NReilly Grant <reillyg@chromium.org>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NEmilio López <emilio.lopez@collabora.co.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Correct attribute name is port_num not num.

Fixes: ea6bd6b1 ("usb-gadget/f_acm: use per-attribute show and store methods")
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NKrzysztof Opasiak <k.opasiak@samsung.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

LPC32xx common clock framework driver correctly manages parent clocks
of USB device clock, so there is no need to manually enable and
disable them from the driver, which now depends only on a single USB
device clock.
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

Direct access to clock control registers can be safely removed, the
task of clock management is done by platform clock driver based on
common clock framework.
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

The driver requires to prepare/unprepare clocks to work properly on a
platform with enabled common clock framework, otherwise unprepared
clocks are not enabled:

    WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:728 clk_core_enable+0x2c/0xf0()
    Modules linked in:
    CPU: 0 PID: 1 Comm: swapper Not tainted 4.3.0-rc2+ #284
    Hardware name: LPC32XX SoC (Flattened Device Tree)
    Backtrace:
    [<>] (dump_backtrace) from [<>] (show_stack+0x18/0x1c)
    [<>] (show_stack) from [<>] (dump_stack+0x20/0x28)
    [<>] (dump_stack) from [<>] (warn_slowpath_common+0x90/0xb8)
    [<>] (warn_slowpath_common) from [<>] (warn_slowpath_null+0x24/0x2c)
    [<>] (warn_slowpath_null) from [<>] (clk_core_enable+0x2c/0xf0)
    [<>] (clk_core_enable) from [<>] (clk_enable+0x24/0x38)
    [<>] (clk_enable) from [<>] (lpc32xx_udc_probe+0x284/0x924)
    [<>] (lpc32xx_udc_probe) from [<>] (platform_drv_probe+0x50/0xa0)
    [<>] (platform_drv_probe) from [<>] (driver_probe_device+0x18c/0x408)
    [<>] (driver_probe_device) from [<>] (__driver_attach+0x70/0x94)
    [<>] (__driver_attach) from [<>] (bus_for_each_dev+0x74/0x98)
    [<>] (bus_for_each_dev) from [<>] (driver_attach+0x20/0x28)
    [<>] (driver_attach) from [<>] (bus_add_driver+0x11c/0x248)
    [<>] (bus_add_driver) from [<>] (driver_register+0xa4/0xe8)
    [<>] (driver_register) from [<>] (__platform_driver_register+0x50/0x64)
    [<>] (__platform_driver_register) from [<>] (__platform_driver_probe+0x54/0x100)
    [<>] (__platform_driver_probe) from [<>] (lpc32xx_udc_driver_init+0x1c/0x28)
    [<>] (lpc32xx_udc_driver_init) from [<>] (do_one_initcall+0x11c/0x1dc)
    [<>] (do_one_initcall) from [<>] (kernel_init_freeable+0x10c/0x1d4)
    [<>] (kernel_init_freeable) from [<>] (kernel_init+0x10/0xec)
    [<>] (kernel_init) from [<>] (ret_from_fork+0x14/0x24)
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

A udc driver should set the giveback status to -ESHUTDOWN in
usb_ep_disable(). Otherwise, a gadget driver (e.g. g_serial) might
request next data wrongly and it is possible to cause kernel panic.
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

Make use of ARCH_RENESAS in place of ARCH_SHMOBILE.

This is part of an ongoing process to migrate from ARCH_SHMOBILE to
ARCH_RENESAS the motivation for which being that RENESAS seems to be a more
appropriate name than SHMOBILE for the majority of Renesas ARM based SoCs.
Acked-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

Fixes a static analysis issue in dwc2_complete_non_isoc_xfer_ddma(). The
qtd was being passed to a function after being freed. It was not being
used in the function so this doesn't fix any bugs. But it fixes up the
warning and makes the code safer by setting qtd to NULL and not using it
at all.
Reported-by: NFelipe Balbi <balbi@kernel.org>
Signed-off-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

Add support for Lantiq ARX and XRX SoC families to the dwc2 driver.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NAntti Seppälä <a.seppala@gmail.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

It is possible for the VBUS detect GPIO interrupt to occur before
nop_set_peripheral() is called, in which case otg->gadget is NULL.
Signed-off-by: NMaarten ter Huurne <maarten@treewalker.org>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

bdc_ep_disable() expects to be called with bdc->lock held.
The assumption is met in all the cases except for call from bdc_udc_exit(),
that is called from bdc_remove(). As a result a race can happen or unheld
bdc->lock can be unlocked in bdc_req_complete().

The patch proposes to acquire-release bdc->lock around bdc_ep_disable()
in bdc_udc_exit().

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: NAlexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

The musb_hdrc_platform_data::config was defined as a non-const pointer.
However some drivers (e.g. the ux500) set up this pointer to point to a
static structure, which is potentially dangerous. Since the musb core
uses the pointer in a read-only manner the const qualifier was added to
protect the content of the config.
Signed-off-by: NPetr Kulhavy <petr@barix.com>
Acked-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NBin Liu <b-liu@ti.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

Move host core initialization and host channel routines into hcd.c. This
allows these functions to only be compiled in host-enabled driver
configurations (DRD or host-only).
Tested-by: NDouglas Anderson <dianders@chromium.org>
Reviewed-by: NDouglas Anderson <dianders@chromium.org>
Signed-off-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

Move the register save and restore functions into the host and gadget
specific files.
Tested-by: NDouglas Anderson <dianders@chromium.org>
Reviewed-by: NDouglas Anderson <dianders@chromium.org>
Signed-off-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

Here, free memory is allocated using kmem_cache_zalloc.  So, use
kmem_cache_free instead of kfree.

This is done using Coccinelle and semantic patch used
is as follows:

//<smpl>
@@
expression x,E,c;
@@
 x =
\(kmem_cache_alloc\|kmem_cache_zalloc\|kmem_cache_alloc_node\)(c,...)
 ... when != x = E
     when != &x
?-kfree(x)
+kmem_cache_free(c,x)
//</smpl>
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NAmitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

The microframe scheduler figured out exactly how many transfers we need
for a split transaction.  Let's use this knowledge to know when to end
things.

Without this I found that certain devices would just keep responding
with tons of NYET resonses on their INT_IN endpoint.  These would just
keep going and going and eventually we'd decide to terminate the
transfer (because the whole frame changed), but by that time the
scheduler would decide that we "missed" the start of the next transfer.
I can also imagine that if we blow past the end of our scheduled time we
may mess up other things that were scheduled to happen.

No known test cases are improved by this patch except that the scheduler
code doesn't yell about MISSES constantly anymore.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

This totally reimplements the microframe scheduler in dwc2 to attempt to
handle periodic splits properly.  The old code didn't even try, so this
was a significant effort since periodic splits are one of the most
complicated things in USB.

I've attempted to keep the old "don't use the microframe" schduler
around for now, but not sure it's needed.  It has also only been lightly
tested.

I think it's pretty certain that this scheduler isn't perfect and might
have some bugs, but it seems much better than what was there before.
With this change my stressful USB test (USB webcam + USB audio + some
keyboards) crackles less.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

When setting up ISO and INT transfers dwc2 needs to specify whether the
transfer is for an even or an odd frame (or microframe if the controller
is running in high speed mode).

The controller appears to use this as a simple way to figure out if a
transfer should happen right away (in the current microframe) or should
happen at the start of the next microframe.  Said another way:

- If you set "odd" and the current frame number is odd it appears that
  the controller will try to transfer right away.  Same thing if you set
  "even" and the current frame number is even.
- If the oddness you set and the oddness of the frame number are
  _different_, the transfer will be delayed until the frame number
  changes.

As I understand it, the above technique allows you to plan ahead of time
where possible by always working on the next frame.  ...but it still
allows you to properly respond immediately to things that happened in
the previous frame.

The old dwc2_hc_set_even_odd_frame() didn't really handle this concept.
It always looked at the frame number and setup the transfer to happen in
the next frame.  In some cases that meant that certain transactions
would be transferred in the wrong frame.

We'll try our best to set the even / odd to do the transfer in the
scheduled frame.  If that fails then we'll do an ugly "schedule ASAP".
We'll also modify the scheduler code to handle this and not try to
schedule a second transfer for the same frame.

Note that this change relies on the work to redo the microframe
scheduler.  It can work atop ("usb: dwc2: host: Manage frame nums better
in scheduler") but it works even better after ("usb: dwc2: host: Totally
redo the microframe scheduler").

With this change my stressful USB test (USB webcam + USB audio +
keyboards) has less audio crackling than before.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

As we start getting more exact about our scheduling it's becoming more
and more important to know exactly how far through the current frame we
are.  This lets us make decisions about whether there's still time left
to start a new transaction in the current frame.

We'll add dwc2_hcd_get_future_frame_number() which will tell you what
the frame number will be a certain number of microseconds (us) from
now.  We can use this information to help decide if there's enough time
left in the frame for a transaction that will take a certain duration.

This is expected to be used by a future change ("usb: dwc2: host:
Properly set even/odd frame").
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the
way it initted / kept track of which frames a QH was going to be active
in.  Let's clean things up a little bit in preparation for a rewrite of
the microframe scheduler.

Specifically:
* Old code would pick a frame number in dwc2_qh_init() and would try to
  pick it "in a slightly future (micro)frame".  As far as I can tell the
  reason for this was that there was a delay between dwc2_qh_init() and
  when we actually wanted to dwc2_hcd_qh_add().  ...but apparently this
  attempt to be slightly in the future wasn't enough because
  dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_
  in the future.  There's no reason not to just pick the frame later.
  For non-periodic QH we now pick the frame in dwc2_hcd_qh_add().  For
  periodic QH we pick the frame at dwc2_schedule_periodic() time.
* The old "dwc2_qh_init() actually assigned to "hsotg->frame_number".
  This doesn't seem like a great idea since that variable is supposed to
  be used to keep track of which SOF the interrupt handler has seen.
  Let's be clean: anyone who wants the current frame number (instead of
  the one as of the last interrupt) should ask for it.
* The old code wasn't terribly consistent about trying to use the frame
  that the microframe scheduler assigned to it.  In
  dwc2_sched_periodic_split() when it was scheduling the first frame it
  always "ORed" in 0x7 (!).  Since the frame goes on the wire 1 uFrame
  after next_active_frame it meant that the SSPLIT would always try for
  uFrame 0 and the transaction would happen on the low speed bus during
  uFrame 1.  This is irregardless of what the microframe scheduler
  said.
* The old code assumed it would get called to schedule the next in a
  periodic split very quickly.  That is if next_active_frame was
  0 (transfer on wire in uFrame 1) it assumed it was getting called to
  schedule the next uFrame during uFrame 1 too (so it could queue
  something up for uFrame 2).  It should be possible to actually queue
  something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP).  To
  do this, code needs to look at the previously scheduled frame when
  deciding when to next be active, not look at the current frame number.
* If there was no microframe scheduler, the old code would check for
  whether we should be active using "qh->next_active_frame ==
  frame_number".  This seemed like a race waiting to happen.  ...plus
  there's no way that you wouldn't want to schedule if next_active_frame
  was actually less than frame number.

Note that this change doesn't make 100% sense on its own since it's
expecting some sanity in the frame numbers assigned by the microframe
scheduler and (as per the future patch which rewries it) I think that
the current microframe scheduler is quite insane.  However, it seems
like splitting this up from the microframe scheduler patch makes things
into smaller chunks and hopefully adds to clarity rather than reduces
it.  The two patches could certainly be squashed.  Not that in the very
least, I don't see any obvious bad behavior introduced with just this
patch.

I've attempted to keep the config parameter to disable the microframe
scheduler in tact in this change, though I'm not sure it's worth it.
Obviously the code is touched a lot so it's possible I regressed
something when the microframe scheduler is disabled, though I did some
basic testing and it seemed to work OK.  I'm still not 100% sure why you
wouldn't want the microframe scheduler (presuming it works), so maybe a
future patch (or a future version of this patch?) could remove that
parameter.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

We'll use the new "scheduler verbose debugging" macro to log missed
SOFs.  This is fast enough (assuming you configure it to use the ftrace
buffer) that we can do it without worrying about the speed hit.  The
overhead hit if the scheduler tracing is set to "no_printk" should be
near zero.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

This no-op change splits code out of dwc2_schedule_periodic() into a
dwc2_do_reserve() function.  This makes it a little easier to follow the
logic.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

This no-op change just reorders a few functions in hcd_queue.c in order
to prepare for future changes.  Motivations here:

The functions dwc2_hcd_qh_free() and dwc2_hcd_qh_create() are exported
functions.  They are not called within the file.  That means that they
should be near the bottom so that they can easily call static helpers.

The function dwc2_qh_init() is only called by dwc2_hcd_qh_create() and
should move near the bottom with it.

The only reason that the dwc2_unreserve_timer_fn() timer function (and
its subroutine dwc2_do_unreserve()) were so high in the file was that
they needed to be above dwc2_qh_init().  Now that dwc2_qh_init() has
been moved down it can be moved down a bit.  A later patch will split
the reserve code out of dwc2_schedule_periodic() and the reserve
function should be near the unreserve function.  The reserve function
needs to be below dwc2_find_uframe() since it calls that.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

This no-op change just does some renames to simplify a future patch.

1. The "interval" field is renamed to "host_interval" to make it more
   obvious that this interval may be 8 times the interval that the
   device sees (if we're doing split transactions).  A future patch will
   also add the "device_interval" field.
2. The "usecs" field is renamed to "host_us" again to make it more
   obvious that this is the time for the transaction as seen by the
   host.  For split transactions the device may see a much longer
   transaction time.  A future patch will also add "device_us".
3. The "sched_frame" field is renamed to "next_active_frame".  The name
   "sched_frame" kept confusing me because it felt like something more
   permament (the QH's reservation or something).  The name
   "next_active_frame" makes it more obvious that this field is
   constantly changing.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

The old code in dwc2_process_periodic_channels() would only enable the
"periodic empty" interrupt if we weren't using DMA.  That wasn't right
since we can still get into cases where we have small FIFOs even on
systems that have DMA (the rk3288 is a prime example).

Let's always enable/disable the "periodic empty" when appropriate.  As
part of this:

* Always call dwc2_process_periodic_channels() even if there's nothing
  in periodic_sched_assigned (we move the queue empty check so we still
  avoid the extra work).  That will make extra certain that we will
  properly disable the "periodic empty" interrupt even if there's
  nothing queued up.

* Move the enable of "periodic empty" due to non-empty
  periodic_sched_assigned to be for slave mode (non-DMA mode) only.
  Presumably this was the original intention of the check for DMA since
  it seems to match the comments above where in slave mode we leave
  things on the assigned queue.

Note that even before this change slave mode didn't work for me, so I
can't say for sure that my understanding of slave mode is correct.
However, this shouldn't change anything for slave mode so if slave mode
worked for someone in the past it ought to still work.

With this change, I no longer get constant misses reported by my other
debugging code (and with future patches) when I've got:
* Rockchip rk3288 Chromebook, using port ff540000
  -> Pluggable 7-port Hub with Charging (powered)
     -> Microsoft Wireless Keyboard 2000 in port 1.
     -> Das Keyboard in port 2.
     -> Jabra Speaker in port 3
     -> Logitech, Inc. Webcam C600 in port 4
     -> Microsoft Sidewinder X6 Keyboard in port 5

...and I'm playing music on the USB speaker and capturing video from the
webcam.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

I find that when I plug a full speed (NOT high speed) hub into a dwc2
port and then I plug a bunch of devices into that full speed hub that
dwc2 goes bat guano crazy.  Specifically, it just spews errors like this
in the console:
  usb usb1: clear tt 1 (9043) error -22

The specific test case I used looks like this:
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=dwc2/1p, 480M
    |__ Port 1: Dev 17, If 0, Class=Hub, Driver=hub/4p, 12M
        |__ Port 2: Dev 19, If 0, ..., Driver=usbhid, 1.5M
        |__ Port 4: Dev 20, If 0, ..., Driver=usbhid, 12M
        |__ Port 4: Dev 20, If 1, ..., Driver=usbhid, 12M
        |__ Port 4: Dev 20, If 2, ..., Driver=usbhid, 12M

Showing VID/PID:
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 001 Device 017: ID 03eb:3301 Atmel Corp. at43301 4-Port Hub
 Bus 001 Device 020: ID 045e:0745 Microsoft Corp. Nano Transceiver ...
 Bus 001 Device 019: ID 046d:c404 Logitech, Inc. TrackMan Wheel

I spent a bunch of time trying to figure out why there are errors to
begin with.  I believe that the issue may be a hardware issue where the
transceiver sometimes accidentally sends a PREAMBLE packet if you send a
packet to a full speed device right after one to a low speed device.
Luckily the USB driver retries and the second time things work OK.

In any case, things kinda seem work despite the errors, except for the
"clear tt" spew mucking up my console.  Chalk it up for a win for
retries and robust protocols.

So getting back to the "clear tt" problem, it appears that we get those
because there's not actually a TT here to clear.  It's my understanding
that when dwc2 operates in low speed or full speed mode that there's no
real TT out there.  That makes all these attempts to "clear the TT"
somewhat meaningless and also causes the spew in the log.

Let's just skip all the useless TT clears.  Eventually we should root
cause the errors, but even if we do this is still a proper fix and is
likely to avoid the "clear tt" error in the future.

Note that hooking up a Full Speed USB Audio Device (Jabra 510) to this
same hub with the keyboard / trackball shows that even audio works over
this janky connection.  As a point to note, this particular change (skip
bogus TT clears) compared to just commenting out the dev_err() in
hub_tt_work() actually produces better audio.

Note: don't ask me where I got a full speed USB hub or whether the
massive amount of dust that accumulated on it while it was in my junk
box affected its funtionality.  Just smile and nod.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Reviewed-by: NKever Yang <kever.yang@rock-chips.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

According to the most up to date version of the dwc2 databook, the FRINT
field of the HFIR register should be programmed to:
* 125 us * (PHY clock freq for HS) - 1
* 1000 us * (PHY clock freq for FS/LS) - 1

This is opposed to older versions of the doc that claimed it should be:
* 125 us * (PHY clock freq for HS)
* 1000 us * (PHY clock freq for FS/LS)

In case you didn't spot it, the difference is the "- 1".

Let's add the "- 1" to match the newest user manual.  It's presumed that
the "- 1" should have always been there and that this was always a
documentation error.  If some hardware needs the "- 1" and other
hardware doesn't, we'll have to add a configuration parameter for it in
the future.

I checked things before and after this patch on rk3288 using a Total
Phase Beagle 5000 analyzer.

Before this patch, a low speed mouse shows constant Frame Timing Jitter
errors.  After this patch errors have gone away.

Before this patch SOF packets move forward about 1 us per 4 ms.  After
this patch the SOF packets move backward about 1 us per 255 ms.  Some
specific SOF timestamps from the analyzer are below.

Before:
  6.603.790
  6.603.916
  6.604.041
  6.604.166
  ...
  6.607.541
  6.607.667
  6.607.792
  6.607.917
  ...
  6.611.417
  6.611.543
  6.611.668
  6.611.793

After:
  6.215.159
  6.215.284
  6.215.408
  6.215.533
  6.215.658
  ...
  6.470.658
  6.470.783
  6.470.907
  ...
  6.726.032
  6.726.157
  6.725.281
  6.725.406
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

In commit 94dfd7ed ("USB: HCD: support giveback of URB in tasklet
context") support was added to give back the URB in tasklet context.
Let's take advantage of this in dwc2.

This speeds up the dwc2 interrupt handler considerably.

Note that this requires the change ("usb: dwc2: host: Add a delay before
releasing periodic bandwidth") to come first.

Note that, as per Alan Stern in
<https://patchwork.kernel.org/patch/7555771/>, we also need to make sure
that the extra delay before the device drivers submit more data doesn't
break the scheduler.  At the moment the scheduler is pretty broken (see
future patches) so it's hard to be 100% certain, but I have yet to see
any new breakage introduced by this delay.  ...and speeding up interrupt
processing for dwc2 is a huge deal because it means we've got a better
chance of not missing SOF interrupts.  That means we've got an overall
win here.

Note that when playing USB audio and using a USB webcam and having
several USB keyboards plugged in, the crackling on the USB audio device
is noticably reduced with this patch.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

We'd like to be able to use HCD_BH in order to speed up the dwc2 host
interrupt handler quite a bit.  However, according to the kernel doc for
usb_submit_urb() (specifically the part about "Reserved Bandwidth
Transfers"), we need to keep a reservation active as long as a device
driver keeps submitting.  That was easy to do when we gave back the URB
in the interrupt context: we just looked at when our queue was empty and
released the reserved bandwidth then.  ...but now we need a little more
complexity.

We'll follow EHCI's lead in commit 9118f9eb ("USB: EHCI: improve
interrupt qh unlink") and add a 5ms delay.  Since we don't have a whole
timer infrastructure in dwc2, we'll just add a timer per QH.  The
overhead for this is very small.

Note that the dwc2 scheduler is pretty broken (see future patches to fix
it).  This patch attempts to replicate all old behavior and just add the
proper delay.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

In preparation for future changes to the scheduler let's add some
tracing that makes it easy for us to see what's happening.  By default
this tracing will be off.

By changing "core.h" you can easily trace to ftrace, the console, or
nowhere.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Reviewed-by: NKever Yang <kever.yang@rock-chips.com>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

We're supposed to keep outstanding splits in order.  Keep track of a
list of the order of splits and process channel interrupts in that
order.

Without this change and the following setup:
* Rockchip rk3288 Chromebook, using port ff540000
  -> Pluggable 7-port Hub with Charging (powered)
     -> Microsoft Wireless Keyboard 2000 in port 1.
     -> Das Keyboard in port 2.

...I find that I get dropped keys on the Microsoft keyboard (I'm sure
there are other combinations that fail, but this documents my test).
Specifically I've been typing "hahahahahahaha" on the keyboard and often
see keys dropped or repeated.

After this change the above setup works properly.  This patch is based
on a previous patch proposed by Yunzhi Li ("usb: dwc2: hcd: fix periodic
transfer schedule sequence")
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Signed-off-by: NYunzhi Li <lyz@rock-chips.com>
Reviewed-by: NKever Yang <kever.yang@rock-chips.com>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NKever Yang <kever.yang@rock-chips.com>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

The queues the the dwc2 host controller used are truly queues.  That
means FIFO or first in first out.

Unfortunately though the code was iterating through these queues
starting from the head, some places in the code was adding things to the
queue by adding at the head instead of the tail.  That means last in
first out.  Doh.

Go through and just always add to the tail.

Doing this makes things much happier when I've got:
* 7-port USB 2.0 Single-TT hub
* - Microsoft 2.4 GHz Transceiver v7.0 dongle
* - Jabra speakerphone playing music
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Reviewed-by: NKever Yang <kever.yang@rock-chips.com>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

When poking around with USB devices with slub_debug enabled, I found
another obvious use after free.  Turns out that in dwc2_hc_n_intr() I
was in a state when the contents of chan->qh was filled with 0x6b,
indicating that chan->qh was freed but chan still had a reference to
it.

Let's make sure that whenever we free qh we also make sure we remove a
reference from its channel.

The bug fixed here doesn't appear to be new--I believe I just got lucky
and happened to see it while stress testing.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Reviewed-by: NKever Yang <kever.yang@rock-chips.com>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

As documented in dwc2_calculate_dynamic_fifo(), host_rx_fifo_size should
really be:
 2 * ((Largest Packet size / 4) + 1 + 1) + n
 with n = number of host channel.

We have 9 host channels, so
 2 * ((1024/4) + 2) + 9 = 516 + 9 = 525

We've got 960 / 972 total_fifo_size on rk3288 (and presumably on
rk3066) and 525 + 128 + 256 = 909 so we're still under on both ports
even when we increment by 5.

In the future, it would be nice if dwc2_calculate_dynamic_fifo() could
handle the "too small" FIFO case and come up with something more
dynamically.  When we do that we can figure out how to allocate the
extra 48 / 60 bytes of FIFO that we're currently wasting.

NOTE: no known bugs are fixed by this patch, but it seems like a simple
fix and ought to fix someone.
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Reviewed-by: NKever Yang <kever.yang@rock-chips.com>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>