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Commit Graph

172 Commits

Author SHA1 Message Date
John Youn
a987a906e9 usb: dwc3: Add a check for the DWC_usb3 core
Add a helper function to check if we are running on a DWC_usb3 core.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-18 13:54:20 +02:00
John Youn
39ebb05ca8 usb: dwc3: gadget: Remove descriptor arguments to ep_enable
The __dwc3_gadget_endpoint_enable() function has access to the endpoint
descriptors via the usb_ep. So we don't need to pass them in as
arguments. The descriptors should be set by the caller prior to calling
usb_ep_enable().

Signed-off-by: John Youn <johnyoun@synopsys.com>

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

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-18 13:54:16 +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
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
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
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
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
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
Thinh Nguyen
9d6173e125 usb: dwc3: Fix dr_mode validation
This patch follows the similar fix in dwc2. See
commit 5268ed9d2e ("usb: dwc2: Fix dr_mode validation")

Currently, the dr_mode is only checked against the module configuration.
It also needs to be checked against the hardware capablities.

The driver now checks if both the module configuration and hardware are
capable of the dr_mode value. If not, then it will issue a warning and
fall back to a supported value. If it is unable to fall back to a
suitable value, then the probe will fail.

Behavior summary:

      module          :  actual
 HW   config  dr_mode :  dr_mode
---------------------------------
 host  host   any     :  host
 host  dev    any     :  INVALID
 host  otg    any     :  host

 dev   host   any     :  INVALID
 dev   dev    any     :  dev
 dev   otg    any     :  dev

 otg   host   any     :  host
 otg   dev    any     :  dev
 otg   otg    any     :  dr_mode

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-09-07 13:29:20 +03:00
John Youn
06281d460f usb: dwc3: Add ENDXFER command polling
ENDXFER polling is available on version 3.10a and later of the
DWC_usb3 (USB 3.0) controller. With this feature, the software can poll
the CMDACT bit in the DEPCMD register after issuing an ENDXFER command.
This feature is enabled by writing GUCTL2[14].

This feature is NOT available on the DWC_usb31 (USB 3.1) IP.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-08-25 12:13:19 +03:00
John Youn
512e47572f usb: dwc3: Add revision numbers for the USB 3.0 IP
Add revision number constants for the 3.00a and 3.10a releases.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-08-25 12:13:18 +03:00
William Wu
00fe081dc3 usb: dwc3: add dis_del_phy_power_chg_quirk
Add a quirk to clear the GUSB3PIPECTL.DELAYP1TRANS bit,
which specifies whether disable delay PHY power change
from P0 to P1/P2/P3 when link state changing from U0
to U1/U2/U3 respectively.

Signed-off-by: William Wu <william.wu@rock-chips.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-08-25 12:13:11 +03:00
William Wu
32f2ed864d usb: dwc3: make usb2 phy utmi interface configurable
Support to configure the UTMI+ PHY with an 8- or 16-bit
interface via DT. The UTMI+ PHY interface is a hardware
capability, and it's platform dependent. Normally, the
PHYIF can be configured during coreconsultant.

But for some specific USB cores(e.g. rk3399 SoC DWC3),
the default PHYIF configuration value is false, so we
need to reconfigure it by software.

Signed-off-by: William Wu <william.wu@rock-chips.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-08-25 12:13:11 +03:00
William Wu
16199f3389 usb: dwc3: add dis_u2_freeclk_exists_quirk
Add a quirk to clear the GUSB2PHYCFG.U2_FREECLK_EXISTS bit,
which specifies whether the USB2.0 PHY provides a free-running
PHY clock, which is active when the clock control input is active.

Signed-off-by: William Wu <william.wu@rock-chips.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-08-25 12:13:11 +03:00
Felipe Balbi
0b3e4af3c7 usb: dwc3: gadget: add sg and num_pending_sgs to dwc3_request
These two fields will be used in a follow-up patch
to track how many entries of request's sglist we
have already processed. The reason is that if a
gadget driver sends an sglist with more entries then
we can fit in the ring, we will have to continue
processing remaining afterwards.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-08-22 10:45:37 +03:00
Felipe Balbi
68d34c8a74 usb: dwc3: gadget: keep track of allocated and queued reqs
We will be using this information to change how we
figure out when we need LST bit. For now, just
update our counters.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-06-20 12:32:49 +03:00
William Wu
475c8beb35 usb: dwc3: add DWC3_GUCTL1 reg for debug
GUCTL1 reg has some useful functions which can be
written by user. For rockchip platform, we set
GUCTL1.DEV_FORCE_20_CLK_FOR_30_CLK (bit26, applicable
for the core is programmed to operate in 2.0 device
only) to 1 in bootrom, and after start the kernel,
we want to check whether this bit can be reset to
default 0 after the core reset. Dump GUCTL1 reg from
debugfs is more convenient for us.

Signed-off-by: William Wu <william.wu@rock-chips.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-06-20 12:32:46 +03:00
John Youn
e77c561432 usb: dwc3: Fix DWC3_USB31_REVISION_110A definition
The DWC3_USB31_REVISION_110A macro uses an invalid constant name in its
definition. This is currently not used.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-06-20 12:32:46 +03:00
Felipe Balbi
74674cbf85 usb: dwc3: gadget: add a per-endpoint request queue lock
This will allow us to process several endpoints at a
time by making sure that we lock only shared
resources.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-06-20 12:32:38 +03:00
Felipe Balbi
fc8bb91bc8 usb: dwc3: implement runtime PM
this patch implements the most basic pm_runtime
support for dwc3. Whenever USB cable is dettached,
then we will allow core to runtime_suspend.

Runtime suspending will involve completely tearing
down event buffers and require a full soft-reset of
the IP.

Note that a further optimization could be
implemented once we decide to support hibernation,
which is to allow runtime_suspend with cable
connected when bus is in U3. That's subject to a
separate patch, however.

Tested-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-06-20 12:32:38 +03:00
Felipe Balbi
3f308d17d7 usb: dwc3: gadget: hold gadget IRQ in dwc->irq_gadget
by holding gadget's IRQ number in dwc->irq_gadget,
it'll be simpler to free_irq() and disable the IRQ
in case an IRQ fires while we are runtime suspended.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-06-20 12:32:36 +03:00
Felipe Balbi
51f5d49ad6 usb: dwc3: core: simplify suspend/resume operations
now that we have re-factored dwc3_core_init() and
dwc3_core_exit() we can use them for suspend/resume
operations.

This will help us avoid some common mistakes when
patching code when we have duplicated pieces of code
doing the same thing.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-06-20 12:32:36 +03:00
Felipe Balbi
bcdb3272e8 usb: dwc3: core: move fladj to dwc3 structure
this patch is in preparation for some further
re-factoring in dwc3 initialization. No functional
changes.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-06-20 12:32:35 +03:00
Felipe Balbi
2eb8801650 usb: dwc3: gadget: add a pointer to endpoint registers
By adding a pointer to endpoint registers' base
address, we can avoid using our controller-wide
struct dwc3 pointer for everything. At some point
this will allow us to have per-endpoint locks which
will, in turn, let us queue requests to separate
endpoints in parallel.

Because of this change our debugfs interface and io
accessors need to be changed accordingly.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-06-20 12:32:35 +03:00
Felipe Balbi
2cd4718d0b usb: dwc3: gadget: pass dep as argument to endpoint command
In all call sites of dwc3_send_gadget_ep_cmd() we
already had a valid dep pointer, so instead of
passing dwc and dep->number, which would be used to
fetch the same pointer we already had, just pass dep
directly.

In other words, we're changing:

	struct dwc3_ep *dep = dwc[dep->number];

to just passing struct dwc3_ep *dep as argument.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-06-20 12:32:31 +03:00
Felipe Balbi
4e99472bc1 usb: dwc3: gadget: initialize NUMP based on RxFIFO Size
Instead of using burst size to configure NUMP, we
should be using RxFIFO Size instead. DWC3 is smart
enough to know that it shouldn't burst in case burst
size is 0.

Reported-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-06-20 12:30:07 +03:00
Felipe Balbi
9f8a67b65a usb: dwc3: gadget: fix gadget suspend/resume
Instead of trying hard to stay connected to the
host, it's best (and far easier) to disconnect from
the host already.

Anything relying on KEEP_CONNECT will just have that
ignored, but we don't have proper hibernation
implementation yet, so there are no regressions.

In any case, hibernation is only useful for runtime
PM, not system sleep.

While at that, also remove dwc3.dcfg which has been
rendered unnecessary.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-06-20 12:30:04 +03:00
John Youn
50c763f8c1 usb: dwc3: Set the ClearPendIN bit on Clear Stall EP command
As of core revision 2.60a the recommended programming model is to set
the ClearPendIN bit when issuing a Clear Stall EP command for IN
endpoints. This is to prevent an issue where some (non-compliant) hosts
may not send ACK TPs for pending IN transfers due to a mishandled error
condition. Synopsys STAR 9000614252.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-06-01 09:53:42 +03:00
Dan Carpenter
973986126a usb: dwc3: gadget: fix mask and shift order in DWC3_DCFG_NUMP()
In the original DWC3_DCFG_NUMP() was always zero.  It looks like the
intent was to shift first and then do the mask.

Fixes: 2a58f9c12b ('usb: dwc3: gadget: disable automatic calculation of ACK TP NUMP')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-03 14:32:07 -07:00
Felipe Balbi
2a58f9c12b usb: dwc3: gadget: disable automatic calculation of ACK TP NUMP
Now that we calculate DCFG.NUMP, we can disable
dwc3's automatic calculation so we maximize our
chances of very high throughtput through the use of
bursts.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-28 10:56:28 +03:00
Felipe Balbi
676e349744 usb: dwc3: gadget: update DCFG.NumP to max burst size
NumP field of DCFG register is used on NumP field of
ACK TP header and it tells the host how many packets
an endpoint can receive before waiting for
synchronization.

Documentation says it should be set to anything
<=bMaxBurst. Interestingly, however, this setting is
not per-endpoint how it should be (different
endpoints could have different burst sizes), but
things seem to work okay right now.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-28 10:47:29 +03:00
Konrad Leszczynski
7b9cc7a2b1 usb: dwc3: gadget: give better command return code
if Start Transfer command fails, let's try a little
harder to figure out why the command failed and give
slightly better return codes. This will be usefulf
or isochronous endpoints, at least, which could
decide to retry a given request.

Signed-off-by: Konrad Leszczynski <konrad.leszczynski@intel.com>
Signed-off-by: Rafal Redzimski <rafal.f.redzimski@intel.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-28 09:02:00 +03:00
Felipe Balbi
b058f3e8a3 usb: dwc3: core: add helper to extract trb type
This helper will be used later to convert trb type
into a human-readable string for debugfs.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-19 11:11:57 +03:00
Felipe Balbi
cf6d867d3b usb: dwc3: core: add fifo space helper
this helper will be used, initially, to dump space
of different queues and fifos in dwc3 to
debugfs. Later, it'll be used to issue remote wakeup
when we want to start a transfer and there's
something in a TX FIFO.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-19 11:11:57 +03:00
Felipe Balbi
70fdb273db usb: dwc3: get rid of DWC3_TRB_MASK
instead of using a bitwise and, let's rely on the %
operator since that's a lot more clear. Also, GCC
will optimize % 256 to nothing anyway.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-19 11:10:45 +03:00
Felipe Balbi
c28f82595d usb: dwc3: switch trb enqueue/dequeue and first_trb_index to u8
We *know* that we have 1 PAGE (4096 bytes) for our
TRB poll. We also know the size of each TRB and know
that we can fit 256 of them in one PAGE. By using a
u8 type we can make sure that:

	enqueue++ % 256;

gets optimized to an increment only.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-18 15:23:49 +03:00
Felipe Balbi
5ef68c56e1 usb: dwc3: core: document struct dwc3_request
No functional changes. Merely adding useful
documentation for future readers.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-18 15:23:48 +03:00
Felipe Balbi
53fd88189e usb: dwc3: gadget: rename busy/free_slot to trb_enqueue/dequeue
This makes it clear that we're dealing with a queue
of TRBs. No functional changes. While at that, also
rename start_slot to first_trb_index for similar
reasons.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-18 15:23:46 +03:00
Rajesh Bhagat
e58dd35774 usb: dwc3: add disable receiver detection in P3 quirk
Some freescale QorIQ platforms require to disable receiver detection
in P3 for correct detection of USB devices. If GUSB3PIPECTL(DISRXDETINP3)
is set, Core will change PHY power state to P2 and then perform receiver
detection. After receiver detection, Core will change PHY power state to
P3. Same quirk would be added in dts file in future patches.

Signed-off-by: Sriram Dash <sriram.dash@nxp.com>
Signed-off-by: Rajesh Bhagat <rajesh.bhagat@nxp.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-18 15:23:44 +03:00
Felipe Balbi
696c8b1282 usb: dwc3: drop ev_buffs array
we will be using a single event buffer and that
renders ev_buffs array unnecessary. Let's remove it
in favor of a single pointer to a single event
buffer.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-14 09:24:39 +03:00
Felipe Balbi
660e9bde74 usb: dwc3: remove num_event_buffers
We never, ever route any of the other event buffers
so we might as well drop support for them.

Until someone has a real, proper benefit for
multiple event buffers, we will rely on a single
one. This also helps reduce memory footprint of
dwc3.ko which won't allocate memory for the extra
event buffers.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-14 09:24:39 +03:00
Felipe Balbi
aa3342c8bb usb: dwc3: better name for our request management lists
request_list and req_queued were, well, weird naming
choices.

Let's give those better names and call them,
respectively, pending_list and started_list. These
new names better reflect what these lists are
supposed to do.

While at that also rename req->queued to req->started.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-14 09:24:38 +03:00
Felipe Balbi
8495036e98 usb: dwc3: increase maximum number of TRBs per endpoint
previously we were using a maximum of 32 TRBs per
endpoint. With each TRB being 16 bytes long, we were
using 512 bytes of memory for each endpoint.

However, SLAB/SLUB will always allocate PAGE_SIZE
chunks. In order to better utilize the memory we
allocate and to allow deeper queues for gadgets
which would benefit from it (g_ether comes to mind),
let's increase the maximum to 256 TRBs which rounds
up to 4096 bytes for each endpoint.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-14 09:24:37 +03:00
Felipe Balbi
bc5081617f usb: dwc3: drop FIFO resizing logic
That FIFO resizing logic was added to support OMAP5
ES1.0 which had a bogus default FIFO size. I can't
remember the exact size of default FIFO, but it was
less than one bulk superspeed packet (<1024) which
would prevent USB3 from ever working on OMAP5 ES1.0.

However, OMAP5 ES1.0 support has been dropped by
commit aa2f4b16f8 ("ARM: OMAP5: id: Remove ES1.0
support") which renders FIFO resizing unnecessary.

Tested-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-04-14 09:24:37 +03:00
John Youn
1f38f88a24 usb: dwc3: Update register fields for SuperSpeedPlus
Update various registers fields definitions for the DWC_usb31 controller
for SuperSpeedPlus support.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-03-04 15:14:26 +02:00
John Youn
c4137a9c84 usb: dwc3: DWC_usb31 controller check
Add a convenience function to check if the controller is DWC_usb31.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-03-04 15:14:26 +02:00
John Youn
c450960187 usb: dwc3: Fix assignment of EP transfer resources
The assignement of EP transfer resources was not handled properly in the
dwc3 driver. Commit aebda61871 ("usb: dwc3: Reset the transfer
resource index on SET_INTERFACE") previously fixed one aspect of this
where resources may be exhausted with multiple calls to SET_INTERFACE.
However, it introduced an issue where composite devices with multiple
interfaces can be assigned the same transfer resources for different
endpoints. This patch solves both issues.

The assignment of transfer resources cannot perfectly follow the data
book due to the fact that the controller driver does not have all
knowledge of the configuration in advance. It is given this information
piecemeal by the composite gadget framework after every
SET_CONFIGURATION and SET_INTERFACE. Trying to follow the databook
programming model in this scenario can cause errors. For two reasons:

1) The databook says to do DEPSTARTCFG for every SET_CONFIGURATION and
SET_INTERFACE (8.1.5). This is incorrect in the scenario of multiple
interfaces.

2) The databook does not mention doing more DEPXFERCFG for new endpoint
on alt setting (8.1.6).

The following simplified method is used instead:

All hardware endpoints can be assigned a transfer resource and this
setting will stay persistent until either a core reset or hibernation.
So whenever we do a DEPSTARTCFG(0) we can go ahead and do DEPXFERCFG for
every hardware endpoint as well. We are guaranteed that there are as
many transfer resources as endpoints.

This patch triggers off of the calling dwc3_gadget_start_config() for
EP0-out, which always happens first, and which should only happen in one
of the above conditions.

Fixes: aebda61871 ("usb: dwc3: Reset the transfer resource index on SET_INTERFACE")
Cc: <stable@vger.kernel.org> # v3.2+
Reported-by: Ravi Babu <ravibabu@ti.com>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-02-17 10:31:53 +02:00