RTL revisions <1.83a have an issue where, depending
on the link partner, the USB link might do multiple
entry/exit of low power states before a transfer
takes place causing degraded throughput.

The suggested workaround is to clear bits
12:9 of DCTL register if we see a transition
from U1|U2 to U0 and only re-enable that on
a transfer complete IRQ and we have no pending
transfers on any of the enabled endpoints.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Since the re-worked ep0 handling (which uses HW's hints to recognize the ep0
status) we lost the delayed status handling. This is used by the file and mass
storage gadget to gain some extra time so setup its internal status before it
can proceed further requests.
In particular the storage gadget does nothing on USB_REQ_SET_CONFIGURATION but
wakes up a thread which handles the request. If the udc driver continues ep0
handling before the thread did its work then then endpoint is not yet
configured and further requests will fail. Once the gadget is ready, it will
enqueue an empty packet which is used for synchronization.
In order to fix this issue, the patch does the following:
Set ->delayed_status once the delayed_status has been notices and do not
continue on the next XferNotReady event. We will continues ep0 processing once
the gadget enqueued the zero packet for synchronization.

A cleaner approach would be to enforce the gadget to enqueue an empty
(zero) request even for the status phase but this would do for now.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

There are two where need to set operational mode:
- during initialization while we decide to run in host,device or DRD
  mode
- at runtime via the debugfs interface.

This patch provides a new function which sets the operational mode and
moves its initialiation to the mode switch instead in the gadget code
itself.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

hardware will tell us how many event buffers we
need to support, so let's allocate the array
dynamically too.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

if we want to support situations where we have
both SoC and PCIe versions of the IP on the same
platform, we need to have sequential numbers between
them, otherwise we will still have name collisions.

Because of that, we need to move dwc3_get/put_device_id()
to core.c and export that symbol to be used by glue
layers.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

The GetStatus (STD)-request is handled the driver and uses a tiny hack
to send the two bytes long answer. This patch removes the custom hack
uses the normal usb_ep_queue() for that.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

This makes testing a lot easier when trying to
switch between host and device modes.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

host prototypes are there, let's move gadget's
closer.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

The Designware USB3 IP can be configured with
an internal xHCI. If we're running on such a
version, let's start the xHCI stack.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

There's no need to add driver_data for something
we can fetch from HW.

This also makes our id_table unnecessary - at least
for now -, so we also remove it on the same patch.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

This will allow us to only allocate memory when
we actually need.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

this is mainly for testing. In order to be able
to test if we're enumerating correctly on all
speeds, let that be controlled by a module
parameter.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

The dwc3 core has internal clock gating support.

Let's allow that to happen by clearing the disable
bit in GCTL register.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

That structure will hold a copy of readonly
GHWPARAMS* registers for ease accessing by
the driver.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The following patch adds support for streams
to dwc3 driver.

While at that, also fix one small issue on
endpoint disable where we should clear all
flags not only ENABLED.
Reviewied-by: NPaul Zimmerman <paulz@synopsys.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

DEPSTARTCFG for non-EP0 EPs must only be sent once per config

[ balbi@ti.com : changed config_start to start_config_issued ]
Signed-off-by: NPaul Zimmerman <paulz@synopsys.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Some people think that this line is not compatible with the GPL. The
statement was required due to the Buenos Aires Convention and is now
deprecated. I remove it because it is said that it is pointless nowdays.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This flag will tell us which direction we're
expecting on the next (data or status) phase.

It will help us catching errors of host going
crazy and requesting data of the wrong direction.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

We must ensure that those bits aren't set as
they should only be used in simulation.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

that should be 1 << 16, not 16. Caused so many
problems and we never caught it before.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

this field will hold the next expected event.

In certain cases, host might fall into some error
condition and ask from us the wrong Control phase.
On such situations, we should stall and restart.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Whenever we issue a Set Stall command on EP0,
the state machine will be restarted and Stall
is cleared automatically, when core receives
the next SETUP packet.

There's no need to track that EP0_STALL state.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

- since a while we are disabling an endpoint and purging every requests on
  RESET and DISCONNECT which leads to a warning since the endpoint was
  disabled twice (once by the UDC, and second time by the gadget). I
  think UDC should nuke all requests because all those requests
  become invalid. It's gadget driver's responsability, though, to disable
  its used endpoints. This is done by merging dwc3_stop_active_transfer()
  and dwc3_gadget_nuke_reqs() into dwc3_remove_requests().

- dwc3_stop_active_transfer() is now no longer called unconditionaly.
  This has the advantage that it is always called to disable an active
  transfer which means if res_trans_idx 0 than something went wrong and
  it is an error condition because we can't clean up the requests.

- Remove the DWC3_EP_WILL_SHUTDOWN which was introduced while
  introducing the command complete part for dequeue. All requests on
  req_queued list should be removed during the dwc3_cleanup_done_reqs()
  callback so there is no reason to go through the list again.
  We consider it an error condition if requests are still on this
  list since we never queue TRB without LST=1 (the last requests has
  always LST=1, there are no requests with LST=0 behind it).

[ balbi@ti.com : reworked commit log a bit, made patch apply ]
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

The DesignWare USB3 core tells us which phase
of a control transfer should be started, it
also tells us which physical endpoint needs
that transfer.

With these two informations, we have all we
need to simply EP0 handling quite a lot and
get rid rid of the SW state machine tracking
ep0 states.

For achieving this perfectly, we needed to
add support for situations where we get
XferNotReady while endpoint is still busy
and XferNotReady while gadget driver still
hasn't queued a request.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Add a flag to keep track of ep0 direction.
This flag will be used on a following patch.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

This core cannot handle OUT transfers which aren't
aligned to wMaxPacketSize, but that can happen at
least on control endpoint with the USB Audio Class.

This patch adds a bounce buffer to be used on the
case of a non-aligned ep0out request is queued.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

The status field of the Transfer Not Read event
is different on Control Endpoints. On this patch
we are just adding the defines to be used on a
later patch which will re-work the control endpoint
handling.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

trivial patch, no functional changes
Signed-off-by: NFelipe Balbi <balbi@ti.com>

The DesignWare USB3 is a highly
configurable IP Core which can be
instantiated as Dual-Role Device (DRD),
Peripheral Only and Host Only (XHCI)
configurations.

Several other parameters can be configured
like amount of FIFO space, amount of TX and
RX endpoints, amount of Host Interrupters,
etc.

The current driver has been validated with
a virtual model of version 1.73a of that core
and with an FPGA burned with version 1.83a
of the DRD core. We have support for PCIe
bus, which is used on FPGA prototyping, and
for the OMAP5, more adaptation (or glue)
layers can be easily added and the driver
is half prepared to handle any possible
configuration the HW engineer has chosen
considering we have the information on
one of the GHWPARAMS registers to do
runtime checking of certain features.

More runtime checks can, and should, be added
in order to make this driver even more flexible
with regards to number of endpoints, FIFO sizes,
transfer types, etc.

While this supports only the device side, for
now, we will add support for Host side (xHCI -
see the updated series Sebastian has sent [1])
and OTG after we have it all stabilized.

[1] http://marc.info/?l=linux-usb&m=131341992020339&w=2Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>