Adds Exynos Specific Glue layer to support USB peripherals
on Samsung Exynos5 chips.

[ balbi@ti.com : prevent compilation of Exynos glue layer
	on platforms which don't provide clk API implementation ]
Signed-off-by: NAnton Tikhomirov <av.tikhomirov@samsung.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

this will get rid of a useless memcpy on
IRQ handling, thus improving driver performance.

Tested with OMAP5430 running g_mass_storage on
SuperSpeed and HighSpeed.

Note that we are removing the little endian access
of the TRB and all accesses will be in System endianness,
if there happens to be a system in BE, bit 12 of GSBUSCFG0
should be set so that HW does byte invariant BE accesses
when fetching TRBs.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

When host requests us to enter a test mode,
we cannot directly enter the test mode before
Status Phase is completed, otherwise the core
will never be able to deliver the Status ZLP
to host, because it has already entered the
requested Test Mode.

In order to fix the error, we move the actual
start of Test Mode right after we receive
Transfer Complete event of the status phase.
Signed-off-by: NGerard Cauvy <g-cauvy1@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

When implementing the USB2 testmode support via debugfs,
Felipe has committed a mistake when counting the number
of letters of some of the strings, resulting on an off
by one error which prevented some of the Test modes to
be entered properly.

This patch, fixes that mistake.
Signed-off-by: NGerard Cauvy <g-cauvy1@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Those transfer types are generally high bandwidth, so we
want to optimize transfers with those endpoints.

For that, databook suggests allocating 3 * wMaxPacketSize
of FIFO. Let's do that.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

We're only using the 4 byte events and memcpy()
will make us slower. We can easily avoid that.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

PCI uses xhci-hcd, so let's use the same device
name to avoid confusion.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

debugfs APIs will return NULL if it fails
to create the file/directory we ask it to
create.

Instead of checking for IS_ERR(ptr) we must
check for !ptr.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Convert our platform_data usage to OF property,
keep the legacy pdata for a while until the complete
conversion is done.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

When we set Run/Stop bit, we also move the
core to Rx.Detect state so that USB3 handshake
can start from a known location.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

We need to dynamically re-size TxFifos for the
cases where default values will not do.

While at that, we create a simple function which,
for now, will just allocate one full packet fifo
space for each of the enabled endpoints.

This can be improved later in order to allow for
better throughput by allocating more space for
endpoints which could make good use of that like
isochronous and bulk.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Mass Storage gadget will take some time to handle
the SetConfiguration request, but even on those
cases we should move to CONFIGURED state.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

We hold that pointer for one reason. It just
looks nicer to use it.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Only bit 3 of the event status bitfield is valid
and the others should not be considered.

Make sure SW matches documentation on that case
to avoid bogus debugging prints which would
confuse an engineer.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

This is very useful for low level link testing where
we might not have a USB Host stack, only a scope to
verify signal integrity.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Most link changes will, of course, happen with
the help of a matching host HW, but in some cases
we might want to debug very low level details about
the link and exposing this to debugfs sounds like
a good plan.

This is a preparation for such setup.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

This is very useful for low level Link Testing where
we might not have a USB Host stack, only a scope to
verify signal integrity.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

There are some situations were we might need to
enable USB Test Modes without having access to a
Host stack. In such situations we cannot rely
solely on USB Control Messages to enable test
features.

For those cases, we will also allow test mode
to be enabled via debugfs and this patch is a
preparation for that.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

num_sgs contains the number of sgs assigned by the gadget.
num_mapped_sgs contains the number of mapped sgs which may differ from
the gadget's values. For dma_unmap_sg() we have to provide the value
which was returned by dma_map_sg().
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

commit 34c60a7 (usb: dwc3: ep0: tidy up Pending
Request handling) introduced a compile warning
by leaving an unused variable.

This patch fixes that warning:

drivers/usb/dwc3/ep0.c: In function ‘__dwc3_gadget_ep0_queue’:
drivers/usb/dwc3/ep0.c:129:8: warning: unused variable ‘type’
[-Wunused-variable]
Signed-off-by: NFelipe Balbi <balbi@ti.com>

The way our code was written, we should never have
a DWC3_EP_PENDING_REQUEST flag set out of a Data Phase
and the code in __dwc3_gadget_ep0_queue() did not
reflect that situation properly.

Tidy up that case to avoid any possible mistakes
when starting requests for IRQs which are long
gone.

Cc: stable@vger.kernel.org
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Glue needs to be freed on exiting the function in an error case.
Furthermore, pci, which is the first argument to the probe function should
not be freed before leaveing the function, as it is reused at the call
site.  So the free of pci is changed to free glue instead.

A simplified version of the semantic match that finds the problem is as
follows: (http://coccinelle.lip6.fr)

// <smpl>
@r exists@
local idexpression x;
statement S;
identifier f1;
position p1,p2;
expression *ptr != NULL;
@@

x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
if (x == NULL) S
<... when != x
     when != if (...) { <+...x...+> }
x->f1
...>
(
 return \(0\|<+...x...+>\|ptr\);
|
 return@p2 ...;
)

@script:python@
p1 << r.p1;
p2 << r.p2;
@@

print "* file: %s kmalloc %s return %s" % (p1[0].file,p1[0].line,p2[0].line)
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

According to USB 3.0 Specification Table 9-22, if
bmAttributes [4:0] are set to zero, it means "no
streams supported", but the way this helper was
defined on Linux, we will *always* have one stream
which might cause several problems.

For example on DWC3, we would tell the controller
endpoint has streams enabled and yet start transfers
with Stream ID set to 0, which would goof up the host
side.

While doing that, convert the macro to an inline
function due to the different checks we now need.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

add support for SG lists on dwc3 driver. With
this we can e.g. use VFS layer's SG lists on
storage gadgets so that we can start bigger
transfers and improve throughput.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

the LST bit is to be set on the last of a series
of consecutive TRBs. We had a workaround for a
problem where data would get corrupted but that
doesn't happen anymore. It's likely that it was
caused by some FPGA instability during development
phase.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

all that function does is setup a TRB to be sent
to HW later. There's no need to return anything
actually.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

In order to make it easier to add SG support,
let's split the big loop out to its own function.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

After a bus reset, we should move our state to
Default, in order to be able to re-enumerate again.

I only managed to trigger this problem with g_ether
by removing the cable after a few transfers had been
completed.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

All our revision macros are defined with the entire
32-bits which we read from GSNPSID register, so we
must cache all 32-bits properly rather than masking
the top 16-bits.

This will fix all revision checks we have on current
driver.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

There is a very small possibility (previously unimagined
by us) that the whole Mass Storage delayed status happens
rather early, before we even get our XferNotReady event.

In that case, we will be queueing a request to ep0 while
we're still on Setup Phase and we would be waiting for
another usb_ep_queue() forever.

Handle such cases by clearing dwc->delayed_status so that
we start control status from the next XferNotReady like
there was no wait for Delayed Status.

Tested against Linux 3.2-rc3 and USB30CV tool from USB-IF
(on a Windows XP with USB3 PCIe card).
Signed-off-by: NFelipe Balbi <balbi@ti.com>

ep->max_streams is a mere hint to the gadget
driver that 'ep' supports stream handling. Using
that as a decision variable for enabling streams
was my worst brain-fart to date.

Instead, we should check from the Superspeed
Endpoint Companion Descriptor if the endpoint
has requested streams. For that we need a little
re-factoring but it is now correct.
Debugged-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

previous commit fixed part of it but it was still
calling usb_ep_queue() from IRQ context without
loosing locks. That cannot be done otherwise we will
have a recursive locking.

Also, we need to assign the 'dep' pointer on
dwc->ep0_usb_req otherwise we will have a NULL
pointer dereference on dwc3_map_buffer_to_dma().
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Instead of special functions and shortcuts for sending our internal
answers to the host we started doing what the gadget does and used the
public API for this. Since we only were using a few fields the
usb_request was enough. Later added the list handling in order to
synchronize the host / gadget events and now we require to have the
dwc3_request struct around our usb_request or else we touch memory that
does not belong to us. So this patch does this.
Reported-by: NPartha Basak <p-basak2@ti.com>
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

We mask the correct bits within the wrong register. The power
optimization mode is stored hwparam1 register and not in hwparam0.
Reported-by: NPartha Basak <p-basak2@ti.com>
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

the new module_platform_driver macro is a helper
for modules which just register and unregister the
platform_driver. It allows us to delete a few
duplicated lines.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

DWC3 revisions <1.88a have an issue which would
case a missing Disconnect event if cable is
disconnected while there's a Setup packet
pending the FIFO.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

DWC3 revisions <1.90a have an issue which would cause
a missing USB3 Reset event. In such cases, it's
suggested that we follow the steps of a normal
USB3 Reset on Connection Done Event.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

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>

This patch avoids the compiler spitting out the following warning:
|drivers/usb/dwc3/gadget.c:1304: warning: 'trb' is used uninitialized \
	in this function

This is only uninitialized if the list of to-cleanup TRBs is empty which
should not be the case because we call this functions once a transfer
completed so it should be on list.

In order to make the warning disappear we return early. This should
never happen and the WARN_ON_ONCE(1) is there in case it happens
so we can investigate what went wrong.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
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>