With all the obstacles removed it is possible to allow more than one
instance of the printer function. Since the function requires allocating
character device region, a maximum number of allowed instances is defined.
Such an approach is used in f_acm and in f_hid.
With multiple instances it does not make sense to depend on a
lock_printer_io member of a dynamically allocated (and destroyed) struct
printer_dev to clean up after all instances of the printer function.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Verify that a given usb_ctrlrequest is meant for printer function.
The following parts of the request are tested:

- bmRequestType:Data transfer direction
- bmRequestType:Type
- bmRequestType:Recipient
- bRequest
- wValue for bRequest 1 and 2
- wLength

Additionally, the request is considered meant for this function
iff the decoded interface number matches dev->interface.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Avoid using magic numbers.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Non-standard requests can encode the actual interface number in a
non-standard way. For example composite_setup() assumes
that it is w_index && 0xFF, but the printer function encodes the interface
number in a context-dependet way (either w_index or w_index >> 8).
This can lead to such requests being directed to wrong functions.

This patch adds req_match() method to usb_function. Its purpose is to
verify that a given request can be handled by a given function.
If any function within a configuration provides the method and it returns
true, then it is assumed that the right function is found.

If a function uses req_match(), it should try as hard as possible to
determine if the request is meant for it.

If no functions in a configuration provide req_match or none of them
returns true, then fall back to the usual approach.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

5 uses of container_of() in the same context justify wrapping it
in a static inline function.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

The printer_dev can be recovered from printer_func_unbind() function's
parameters.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

The mutex is a legacy after semi-automatic Big Kernel Lock removal.
printer_open() does its own locking, so no need to duplicate it.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Call gprinter_setup() from gadget's bind instead of module's init.
Call gprinter_cleaup() corerspondingly. This detaches printer function's
logic from legacy printer gadget's implementation.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Factor out gprinter_setup() and gprinter_cleanup() so that it is
easy to change the place they are called from.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

In order to factor out a reusable f_printer, the function's code should
not use file global variables related to legacy printer gadget's
implementation.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Avoid using magic numbers.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

In order to factor out a reusable f_printer.c, the code related to the
function should be placed in functions related to the function.

printer_cfg_unbind() becomes empty, so it is removed.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Conversion to the new function interface requires splitting a
<something>_bind_config() function into two parts: allocation of
container_of struct usb_function and invocation of usb_add_function().
This patch moves the latter to the end of the f_printer_bind_config()
in order to enable conversion to the new interface.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

In order to factor out a reusable f_printer.c, the code related to the
function should be placed in functions related to the function.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Follow the convention of distributing source code between
<something>_do_config() and <something>_bind_config().
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Legacy gadgets, before converting them to the new function framework,
used to use the name <something>_do_config() for usb_add_config()'s
callback.

This patch changes the name so that it is easier to follow
the convention.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

The pdev member of struct printer_dev is not used outside
printer_bind_config(), so it can just as well be a local variable there.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

If cdev_add() in printer_bind_config() fails, care is taken to
reverse the effects of initializations completed until the fail
happens. But if printer_req_alloc() fails, it is just one of the
two lists that is cleaned up while the effects of cdev_add()
and device_create() are not reverted.

This patch changes error handling so that at least as much cleanup is done
as when a failure happens before printer_req_alloc() invocations.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Whenever the "goto fail" branch is taken, the effect of usb_add_function()
should be reverted.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

struct printer_dev contains 3 list heads: tx_reqs, rx_reqs and rx_buffers.
There is just one instance of this structure in the driver and it is
file static, and as such initialized with all zeros.

If device_create() or cdev_add() fails then "goto fail" branch is taken,
which results in printer_cfg_unbind() call. The latter checks if
tx_reqs, rx_reqs and rx_buffers lists are empty. The check for emptiness
is in fact a check whether the "next" member of struct list_head points
to the head of the list. But the heads of the lists in question have
not been initialized yet and, as mentioned above, contain all zeros,
so list_empty() returns false and respective "while" loop body starts
executing. Here, container_of() just subtracts the offset of a struct
usb_request member from an address of this same member, which results in
a value somewhere near 0 or 0xfff...ff. And the argument to list_del()
dereferences such a pointer which causes a disaster.

This patch moves respective INIT_LIST_HEAD() invocations to a point before
"goto fail" branch can be taken.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

The unbind() method is optional is usb_composite_driver.
In this particular driver the method does nothing so it can be removed.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Function-specific setup requests should be handled in such a way, that
apart from filling in the data buffer, the requests are also actually
enqueued: if function-specific setup is called from composte_setup(),
the "usb_ep_queue()" block of code in composite_setup() is skipped.

The printer function lacks this part and it results in e.g. get device id
requests failing: the host expects some response, the device prepares it
but does not equeue it for sending to the host, so the host finally asserts
timeout.

This patch adds enqueueing the prepared responses.

Cc: <stable@vger.kernel.org> # v3.4+
Fixes: 2e87edf4: "usb: gadget: make g_printer use composite"
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

If a non-standard request is processed and its parameters just happen
to match those of some standard request, the logic of composite_setup()
can be fooled, so don't even try any switch cases, just go to the
proper place where unknown requests are handled.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

This patch removes "Enable USB3 LPM Capability" option from Kconfig
and adds snps,usb3_lpm_capable devicetree property instead of it.

USB3 LPM (Link Power Management) capability is hardware property, and
it's platform dependent, so if our hardware supports this feature, we
want rather to configure it in devicetree than having it as Kconfig option.
Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

there's no need to fake an IRQ, just check
if VBUS is valid already.
Signed-off-by: Felipe Balbi <balbi@ti.com>

when polling, we were using n * HZ (where n is
an integer in seconds), however HZ isn't always
correct if we're using cpufreq. A better way
is to use msecs_to_jiffies(n) (where n is now
an integer in miliseconds).

while at that, also rename poll_seconds to poll_timeout
and  change its type to unsigned int.
Signed-off-by: Felipe Balbi <balbi@ti.com>

according to comment in code, HS completion
will happen pretty fast, instead of using
udelay(), let's just busy loop and drop a
cpu_relax() where udelay() was.
Signed-off-by: Felipe Balbi <balbi@ti.com>

as soon as we find out tx fifo is empty, there's
no need to break out of the loop just to have another
branch to complete the transfer. We can just complete
transfer and exit early.
Signed-off-by: Felipe Balbi <balbi@ti.com>

no functional changes, clean up only.
Signed-off-by: Felipe Balbi <balbi@ti.com>

Silence the following warning:

drivers/usb/gadget/udc/net2280.c:3176:33: warning: context imbalance in
'handle_stat1_irqs' - unexpected unlock
Signed-off-by: Felipe Balbi <balbi@ti.com>

net2280_start can be called with pullup disabled. Don't set
softconnect flag in it. Let net2280_pullup handle the connection part.
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Hopefully, these prints will help localize the problems faster.

[ balbi@ti.com: removed 2 unnecessary OOM error messages ]
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Remove fiforegs from struct net2280 and net2280_ep as it is unused.
By the way, ep->fiforegs = &dev->fiforegs[i] assignment is incorrect.
It should be ep->fiforegs = &dev->fiforegs[ne[i]], but it doesn't
matter now.
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Each struct usb_ep added for net2280 can be used in either direction.
Whereas, each struct usb_ep for usb3380 has fixed direction. Use
ep_autoconf compatible names so that endpoint with correct direction
can be selected.

Name sequence is due to the logic in usb_reinit_338x() in ne[] and
ep_reg_addr[].
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

we can also have babble conditions with LS/FS
and we also want to recover in that case.

Because of that we will drop the check of HSMODE
and always try to run babble recovery.
Suggested-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

There's no point is splitting those anymore.

We're now also able to drop another forward
declaration.
Tested-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

no functional changes, cleanup only.
Tested-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

that's not needed anymore. Everything that we
call is irq-safe, so we might as well not
have a delayed work for babble recovery.
Tested-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

recover is a much better name than reset, considering
we don't really reset the IP, just run platform-specific
babble recovery algorithm.

while at that, also fix a typo in comment and add kdoc
for recover memeber of platform_ops.
Tested-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

we're not resetting musb at all, just restarting
the session. This means we don't need to touch PHYs
or VBUS or anything like that. Just make sure session
bit is reenabled after MUSB dropped it.

while at that, make sure to tell usbcore that we're
dropping the session and, thus, disconnecting the
device.
Tested-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>