Commit Graph

863 Commits

Author SHA1 Message Date
Felipe Balbi 5eb30cedce usb: dwc3: trace: purge dwc3_trace()
Finally get rid of dwc3_trace() hack. If any other
message is truly needed, we should add proper
tracepoints for them instead of hacking around with
dwc3_trace() or similar.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-08 12:52:13 +02:00
Felipe Balbi 2870e5013e usb: dwc3: trace: add a tracepoint for ep enable/disable
instead of using a simple trace_printk() wrapper,
let's add an actual tracepoint and print further
details about the endpoint being operated upon.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-08 12:52:12 +02:00
Felipe Balbi 9cecca75b5 usb: dwc3: pci: call _DSM for suspend/resume
Intel's BXT devices need to execute a _DSM method
during {runtime_,}{suspend,resume} in order to get a
chunk of dwc3 to power gate and save some extra
power.

Let's do that now.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:42 +02:00
Felipe Balbi 0f817ae696 usb: dwc3: pci: add a private driver structure
We'll be tracking a little more information for PCI
drivers, it's about time we add a private structure
for that.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:41 +02:00
Felipe Balbi ff377ae47d usb: dwc3: gadget: always kick if num_pending_sgs > 0
When we get a half-way processed request, we should
make sure to try to prepare further TRBs for it or
for any possibly queued up request held in our
pending_list. This will make sure our controller is
kept busy for as long as possible.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:41 +02:00
Felipe Balbi 7282c4ef0b usb: dwc3: gadget: stop touching HWO TRBs
Say we have three requests prepared to the HW (reqA,
reqB, and reqC). All of them are composed of
SG-lists with several entries and they all requests
interrupt only on last TRBs of the SG-list.

When we get interrupt for reqA, it could be that
reqB is already half-way transferred and some of its
TRBs will have HWO already cleared.

It's okay to free up TRBs without HWO bit set, but
we need to guarantee we don't giveback a request
that's half-way transferred as that will confuse
gadget drivers.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:41 +02:00
Felipe Balbi d86c5a676e usb: dwc3: gadget: always try to prepare on started_list first
In cases where we're given an SG-list which is
longer than the amount of currently available TRBs,
we will be left with the same request on
started_list and we should prioritize that request
over possible new requests on pending_list. That's
a way to guarantee requests complete in order.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:40 +02:00
Felipe Balbi e62c5bc573 usb: dwc3: gadget: tracking per-TRB remaining bytes
This will give us a simpler way of figuring out how
many bytes were left in each TRB. It's useful for
cases where we queue only part of an SG-list due to
amount of available TRBs at the time of kicking the
transfer.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:40 +02:00
Felipe Balbi 6cb2e4e3de usb: dwc3: gadget: cope with XferNotReady before usb_ep_queue()
If XferNotReady comes before usb_ep_queue() we will
set our PENDING request flag and wait for a
request. However, originally, we were assuming
usb_ep_queue() would always happen before our first
XferNotReady and that causes a corner case where we
could try to issue ENDTRANSFER command before
STARTTRANSFER.

Let's fix that by tracking endpoints which have been
started.

Reported-by: Janusz Dziedzic <januszx.dziedzic@intel.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:40 +02:00
Baolin Wang 76a638f8ac usb: dwc3: gadget: wait for End Transfer to complete
Instead of just delaying for 100us, we should
actually wait for End Transfer Command Complete
interrupt before moving on. Note that this should
only be done if we're dealing with one of the core
revisions that actually require the interrupt before
moving on.

[ felipe.balbi@linux.intel.com: minor improvements ]

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:39 +02:00
Masahiro Yamada 785c91f8ae usb: dwc3: cleanup with list_first_entry_or_null()
The combo of list_empty() check and return list_first_entry()
can be replaced with list_first_entry_or_null().

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:37 +02:00
Baolin Wang bb01473648 usb: dwc3: gadget: don't clear RUN/STOP when it's invalid to do so
When we change the USB function with configfs dynamically, we possibly
met this situation: one core is doing the control transfer, another core
is trying to unregister the USB gadget from userspace, we must wait for
completing this control tranfer, or it will hang the controller to set
the DEVCTRLHLT flag.

[ felipe.balbi@linux.intel.com: several fixes to the patch
	- call complete() before starting following SETUP transfer
	- add a macro for ep0_in_setup's timeout
	- change commit subject slightly
	- break lines at 72 characters (git adds an 8-character tab)
	- avoid changes to dwc3_gadget_run_stop() ]

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:35 +02:00
Felipe Balbi cf68923055 usb: dwc3: gadget: purge dwc3_stop_active_transfers()
That function is unnecessarily called from
dwc3_gadget_reset_interrupt(). Gadget drivers (and
thus, functions) are required to dequeue all pending
requests when they get notified about a USB Bus
Reset.

Trying to make sure there are no pending requests
only serves the purpose of working around possibly
bad gadgets.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:35 +02:00
Felipe Balbi c5ac6116db usb: dwc3: core: add dwc3_get_properties()
This helper will be responsible for reading and
parsing our properties. No functional changes in
this patch, cleanup only.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:35 +02:00
Felipe Balbi 3b2733227f usb: dwc3: core: remove unnecessary alignment
Kernel will give us page aligned memory anyway.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:34 +02:00
Felipe Balbi 941f918ecf usb: dwc3: core: introduce dwc3_core_setup_global_control()
This little helper will be used to setup anything
related to GCTL register. There are no functional
changes, this is a cleanup only patch.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:34 +02:00
Felipe Balbi 0759956f8a usb: dwc3: core: introduce dwc3_core_is_valid()
This little helper will be used to make sure we're
dealing with a valid Synopsys DWC3 or DWC3.1 core.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:34 +02:00
John Youn 0bb39ca1ad usb: dwc3: Add support for device L1 exit
For the usb31 IP and from version 2.90a of the usb3 IP, the core
supports HW exit from L1 in HS. Enable it, otherwise the controller may
never exit from LPM to do a transfer.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:33 +02:00
Lu Baolu f9d2f9228c usb: dwc3: remove unused struct member dwc3->mem
Member @mem in struct dwc3 is not used in any places. Clean up it.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:33 +02:00
Felipe Balbi 0a695d4c75 usb: dwc3: gadget: never ever kill the machine
We should never kill the machine just because some
USB endpoint type is wrong. WARN about it and move
on.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:32 +02:00
Felipe Balbi c9508c8c50 usb: dwc3: gadget: only interrupt on short if short_not_ok is set
We don't need to know about short packets unless
gadget driver told us it's not ok to see them on the
bus. In the normal situation we can continue
processing the list of requests if we get a Short
packet.

Also, note that we're making sure ISP is only set
for OUT endpoints, where that setting is valid.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:32 +02:00
Felipe Balbi 58f29034b4 usb: dwc3: gadget: CSP is only valid for OUT endpoints
CSP bit is only valid for OUT endpoints. Synopsys
databook is unclear if HW ignores CSP for IN
endpoints (chances are, it does) but to avoid
problems, let's make sure to set CSP only when valid
to do so.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:32 +02:00
Felipe Balbi b9bd138e06 usb: dwc3: gadget: remove unused 'first_trb_index'
Recent changes have turned this field obsolete. Remove it.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:31 +02:00
Felipe Balbi 39e07ffb1c usb: dwc3: ep0: simplify dwc3_ep0_handle_feature()
By extracting smaller functions from
dwc3_ep0_handle_feature(), it becomes far easier to
understand what's going on. Cleanup only, no
functional changes.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:31 +02:00
Felipe Balbi 6d729a55cc usb: dwc3: host: extract dwc3_host_get_irq()
Cleanup only, no functional changes.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:31 +02:00
Felipe Balbi 6db3812e09 usb: dwc3: gadget: extract dwc3_gadget_get_irq()
Cleanup only, no functional changes.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:30 +02:00
Felipe Balbi 4dd5a69e49 usb: dwc3: trace: add a proper tracepoint for reg accessors
We want to reduce the usage of dwc3_trace() in favor
of proper tracepoints which can be enabled/disabled
by the user. Let's start with our register
accessors.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:30 +02:00
Felipe Balbi ba1773fb7d usb: dwc3: Kconfig: allow all glues to build if COMPILE_TEST
We shouldn't have any glue layer which doesn't
compile everywhere. In order to make sure this is
always the case, make sure COMPILE_TEST is properly
added at dependency list of a config entry.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:30 +02:00
Felipe Balbi 57b14da562 usb: dwc3: don't compile dwc3_trace() unless CONFIG_FTRACE=y
We don't need dwc3_trace() unless we're building a
kernel with CONFIG_FTRACE. This patch reduces
dwc3.ko text size a bit while also removing overhead
of dwc3_trace() calls.

   text    data     bss     dec     hex filename
  50796     581       0   51377    c8b1 drivers/usb/dwc3/dwc3.o
  43961     581       0   44542    adfe drivers/usb/dwc3/dwc3.o.patched

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:29 +02:00
Felipe Balbi a97ea99460 usb: dwc3: gadget: offset Start Transfer latency for bulk EPs
We can offset the latency of a full Start Transfer
command - where we _must_ poll for its completion -
to usb_ep_enable() time. This means that once
requests start showing up from the gadget driver, we
can rely on No Response Update Transfer command -
where we don't need to poll for completion.

This patch, starts implementing this method for Bulk
endpoints, even though, technically, we could extend
it to all other endpoints in future commits.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:29 +02:00
Felipe Balbi fa8d965d73 usb: dwc3: trace: pretty print high-bandwidth transfers too
In case of periodic transfers, let's pretty print
the size field as a multiplier followed by length,
such as :

	3x 1024

instead of:

	33555456

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:28 +02:00
Felipe Balbi 43c96be1c4 usb: dwc3: trace: print out ep0state also from XferComplete
With this extra piece of information, it will be
easier to find mismatches between driver and HW.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-10-31 11:17:34 +02:00
Felipe Balbi cdd72ac20b usb: dwc3: debug: move dwc3_ep0_state_string() to debug.h
We will be using dwc3_ep0_state_string() from within
our tracepoints, so we need to move that helper to
debug.h in order for it to be accessible.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-10-31 11:17:34 +02:00
Felipe Balbi 8566cd1adf usb: dwc3: gadget: remove redundant trace prints
Removing some trace prints which were made redundant
when we started decoding events and TRBs completely
within their respective trace points.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-10-31 11:15:36 +02:00
Felipe Balbi 45a2af2f2b usb: dwc3: debug: decode control endpoint phase too
DWC3 can tell us which phase of a setup transfer
we're getting into. Let's decode it from the event
to make it easier to debug.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-10-31 11:15:36 +02:00
Felipe Balbi 799e9dc829 usb: dwc3: gadget: conditionally disable Link State change events
Link State Change events are only needed for
debugging and to apply certain workarounds on known
errata. Let's save a few cycles by disabling these
events completely on working revisions of the core.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-10-31 11:15:35 +02:00
Felipe Balbi 15b8d9332b usb: dwc3: gadget: giveback request if we can't kick it
There might be situations where a Start Transfer
command might fail, if that ever happens, instead of
simply removing the request from our list, we should
give the request back to the gadget driver,
otherwise we might eventually starve it from requests.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-10-31 11:15:35 +02:00
Felipe Balbi 8897a761c3 usb: dwc3: gadget: make use of No Response Update Transfer
No Response Update Transfer is a special type of
Update Transfer command which can be used whenever
we're not relying on XferNotReady to prepare
transfers. With this, we don't need to wait for
CMDACT to be cleared and issue further commands to
the endpoint straight away.

Let's start using this version to skip the long-ish
wait.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-10-31 11:15:34 +02:00
Felipe Balbi 5999914f22 usb: dwc3: gadget: properly check ep cmd
The cmd argument we pass to
dwc3_send_gadget_ep_cmd() could contain extra
arguments embedded. When checking for StartTransfer
command, we need to make sure to match only lower 4
bits which contain the actual command and ignore the
rest.

Reported-by: Janusz Dziedzic <januszx.dziedzic@intel.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-10-31 11:15:34 +02:00
Felipe Balbi 6b9018d4c1 usb: dwc3: gadget: set PCM1 field of isochronous-first TRBs
In case of High-Speed, High-Bandwidth endpoints, we
need to tell DWC3 that we have more than one packet
per interval. We do that by setting PCM1 field of
Isochronous-First TRB.

Cc: <stable@vger.kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-10-31 11:15:34 +02:00
Christophe JAILLET 51fbc7c06c usb: dwc3: Fix size used in dma_free_coherent()
In commit 2abd9d5fa6 ("usb: dwc3: ep0: Add chained TRB support"), the
size of the memory allocated with 'dma_alloc_coherent()' has been modified
but the corresponding calls to 'dma_free_coherent()' have not been updated
accordingly.

This has been spotted with coccinelle, using the following script:
////////////////////
@r@
expression x0, x1, y0, y1, z0, z1, t0, t1, ret;
@@

*   ret = dma_alloc_coherent(x0, y0, z0, t0);
    ...
*   dma_free_coherent(x1, y1, ret, t1);

@script:python@
y0 << r.y0;
y1 << r.y1;

@@
if y1.find(y0) == -1:
 print "WARNING: sizes look different:  '%s'   vs   '%s'" % (y0, y1)
////////////////////

Fixes: 2abd9d5fa6 ("usb: dwc3: ep0: Add chained TRB support")

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-10-17 12:35:48 +03:00
Felipe Balbi d889c23ce4 usb: dwc3: gadget: never pre-start Isochronous endpoints
We cannot pre-start isochronous endpoints because we
rely on the micro-frame number passed via
XferNotReady command for proper Isochronous
scheduling.

Fixes: 08a36b5438 ("usb: dwc3: gadget: simplify __dwc3_gadget_ep_queue()")
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-10-17 11:14:00 +03:00
Felipe Balbi a9c3ca5fae usb: dwc3: gadget: properly account queued requests
Some requests could be accounted for multiple
times. Let's fix that so each and every requests is
accounted for only once.

Cc: <stable@vger.kernel.org> # v4.8
Fixes: 55a0237f8f ("usb: dwc3: gadget: use allocated/queued reqs for LST bit")
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-10-17 11:14:00 +03:00
Greg Kroah-Hartman 8152263748 usb: patches for v4.9 merge window
This time around we have 92 non-merge commits. Most
 of the changes are in drivers/usb/gadget (40.3%)
 with drivers/usb/gadget/function being the most
 active directory (27.2%).
 
 As for UDC drivers, only dwc3 (26.5%) and dwc2
 (12.7%) have really been active.
 
 The most important changes for dwc3 are better
 support for scatterlist and, again, throughput
 improvements. While on dwc2 got some minor stability
 fixes related to soft reset and FIFO usage.
 
 Felipe Tonello has done some good work fixing up our
 f_midi gadget and Tal Shorer has implemented a nice
 API change for our ULPI bus.
 
 Apart from these, we have our usual set of
 non-critical fixes, spelling fixes, build warning
 fixes, etc.
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Merge tag 'usb-for-v4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next

Felipe writes:

usb: patches for v4.9 merge window

This time around we have 92 non-merge commits. Most
of the changes are in drivers/usb/gadget (40.3%)
with drivers/usb/gadget/function being the most
active directory (27.2%).

As for UDC drivers, only dwc3 (26.5%) and dwc2
(12.7%) have really been active.

The most important changes for dwc3 are better
support for scatterlist and, again, throughput
improvements. While on dwc2 got some minor stability
fixes related to soft reset and FIFO usage.

Felipe Tonello has done some good work fixing up our
f_midi gadget and Tal Shorer has implemented a nice
API change for our ULPI bus.

Apart from these, we have our usual set of
non-critical fixes, spelling fixes, build warning
fixes, etc.
2016-09-14 20:37:50 +02:00
Felipe Balbi b281dc630b usb: dwc3: of-simple: add compatible for Cavium
Add necessary compatible flag for Cavium's DWC3 so
dwc3-of-simple will probe.

Tested-by: Steven J. Hill <Steven.Hill@cavium.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-09-13 09:28:59 +03:00
Felipe Balbi 26c9cac402 usb: dwc3: of-simple: allow glues without clocks
Instead of erroring out when we don't have clocks,
let's just avoid any calls to the clk API.

Tested-by: Steven J. Hill <Steven.Hill@cavium.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-09-13 08:40:40 +03:00
Greg Kroah-Hartman fc9104d5d7 Merge 4.8-rc6 into usb-next
We want the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-12 09:15:26 +02:00
Anurag Kumar Vulisha 8d53e62675 usb: dwc3: of-simple: Fix warning during unbind
In dwc3_of_simple_remove() we are using clk_unprepare() before doing
any clk_disable(). If we enable Common CLK framework (CCF) and try to
unbind dwc3-of-simple driver, we see kernel WARN messages.

This patch fixes this kernel warning by using clk_disable_unprepare()
instead of clk_unprepare().

Signed-off-by: Anurag Kumar Vulisha <anuragku@xilinx.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-09-12 10:07:24 +03:00
Lu Baolu 5e6c88d28c usb: dwc3: fix Clear Stall EP command failure
Commit 50c763f8c1 ("usb: dwc3: Set the ClearPendIN bit on Clear
Stall EP command") sets ClearPendIN bit for all IN endpoints of
v2.60a+ cores. This causes ClearStall command fails on 2.60+ cores
operating in HighSpeed mode.

In page 539 of 2.60a specification:

"When issuing Clear Stall command for IN endpoints in SuperSpeed
mode, the software must set the "ClearPendIN" bit to '1' to
clear any pending IN transcations, so that the device does not
expect any ACK TP from the host for the data sent earlier."

It's obvious that we only need to apply this rule to those IN
endpoints that currently operating in SuperSpeed mode.

Fixes: 50c763f8c1 ("usb: dwc3: Set the ClearPendIN bit on Clear Stall EP command")
Cc: <stable@vger.kernel.org> # v4.7+
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-09-12 10:05:55 +03:00
Arnd Bergmann d6e10bf2ba usb: dwc3: avoid -Wmaybe-uninitialized warning
Cleaning up the loop in dwc3_cleanup_done_reqs() introduced a
gcc warning if built with "-Wmaybe-uninitialized":

drivers/usb/dwc3/gadget.c: In function 'dwc3_endpoint_transfer_complete':
drivers/usb/dwc3/gadget.c:2015:9: 'trb' may be used uninitialized in this function [-Wmaybe-uninitialized]

I believe it is a false positive and we always have a valid 'trb'
pointer at the end of the function, but neither I nor the compiler
are able to prove that.

This works around the warning by computing a flag earlier in the function
when it's guaranteed to be valid, which tells the compiler that it's
safe and makes it easier to understand to me.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 31162af447 ("usb: dwc3: gadget: avoid while (1) loop on completion")
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-09-09 14:56:06 +03:00