A Greybus buffer containing outbound data is submitted to to the
underlying driver to be sent over a CPort.  Sending that data could
be deferred, so the submit operation completes asynchronously.  When
the send is done, a callback occurs, and the buffer is "completed",
and the buffer's completion routine is called.  The buffer is then
freed.

If data arrives on the CPort, greybus_cport_in_data() is called
to allocate a Greybus buffer and copy the received data into it.
Once that's done the buffer is completed, again allowing the
buffer's completion routine to finish any final tasks before
freeing the buffer.

We use a workqueue to schedule calling the buffer's completion
function.  This patch does two things related to the work queue:
    - Renames the work queue "gbuf_workqueue" so its name more
      directly describes its purpose
    - Moves the work_struct needed for scheduling completions
      into the struct greybuf.  Previously a separate type
      was used, and dynamically allocated *at interrupt time*
      to hold this work_struct.  We can now do away with that.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

It strikes me as strange to add one to a value while checking to see
if it exceeds a maximum.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

Let the serial number attribute have its own is_visible function.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

The greybus_device structure represents an Ara phone module.
It does *not* (necessarily) represent a UniPro device, nor any
device (like an i2c adapter) that might reside on an Ara module.

As such, rename struct greybus_device to be struct greybus_module.
Rename all symbols having that type to be "gmod" rather than "gdev".
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

A few silly little fixes.
    - Clear out some unnecessary #includes in "debugfs.c"
    - Drop some unneeded parentheses in hd_to_es1()
    - Use &hd->hd_priv in hd_to_es1() to emphasize we are working
      with an embedded array, not a pointer
    - Fix a comment in the header for ap_probe()
    - Drop a duplicate #include in "gpio-gb.c"
    - Fix a use-before-set problem in set_serial_info()
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

Currently only the handshake_type is being initialized when
responding to an SVC handshake request. Update this to
explicitly set all header/payload fields appropriately.
Signed-off-by: Matt Porter <mporter@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

The control message flags currently indicate USB_DIR_IN, which
doesn't allow the data phase carrying the SVC message to be
send to the device. Change this to USB_DIR_OUT so our SVC
message buffer reaches the device.

Also, the recipient is USB_RECIP_OTHER but almost all real devices
that handle vendor setup requests seem to set this as
USB_RECIP_INTERFACE. As a result, functionfs-based gadgets don't handle
vendor setup requests with a recipient of OTHER. Change this to
USB_RECIP_INTERFACE to work with the functionfs-based emulator and
this should be no issue for the firmware to implement to match.
Signed-off-by: Matt Porter <mporter@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

We should now try to parse the manifest and create a device based on the
manifest.  Not hooked up to the driver core yet, so removing it isn't
going to do anything except cause problems...

We check the type of the message now.

Start to check the size of the payload to match the size of the message
type.  Still more work to do needed here.

Also "hooked up" the hotplug message, but doesn't call anything as the
core doesn't implement that yet...

Started documenting the gbuf and how a greybus driver and a host
controller driver needs to interact with it, and the rest of the greybus
system.  It's crude documentation, but better than nothing for now...

The gbuf sizes are 4k (i.e. PAGE_SIZE) and svc interrupt urb is 2k

The Greybus spec was updated to have major=0 and minor=1 so update
this in the code.
Signed-off-by: Matt Porter <mporter@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

The Greybus spec has been updated to improve the efficiency of the
version major/minor information that had been previously carried in
every SVC message header. The version major/minor is now provided
as part of the handshake function.

Update the SVC msg header and handshake function payload definitions
and move the version major/minor validation into the SVC handshake
handling routine.
Signed-off-by: Matt Porter <mporter@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

The Greybus spec has been updated to clarify some of the original
intent of the SVC message definition. The svc_msg_header was:

struct svc_msg_header {
	__u8 function;
	__u8 message_type;
...
}

and is now

struct svc_msg_header {
	__u8 function_id;
	__u8 message_type;
...
}

to match the spec. The function_id carries enum svc_function_id values
and message_type is now clarified to be a session layer level field
that is simply "data" or "error".

Change all references of function type to function id. For now, don't
parse the message_type field but add the two allowable svc_msg_type enums.
Signed-off-by: Matt Porter <mporter@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

Have only tested USB device add/remove, the urbs seem to all be queued
up, no data has been tested to flow through yet.

Odds are the hc interface will have to change, but this is a good first
start to build on.

Don't register the tty_gb_driver, the gb core is not ready for the for
ES1 devices.

Add a send_svc_msg() callback to the host driver.
hook up ES1 driver to send control USB messages as it's SVC transport.

Thanks to Marti for pointing out the code didn't build properly on 3.10.
Added kernel_ver.h to handle any api mis-matches between the code and
older kernel versions.

Based on a patch from Alex Elder <elder@linaro.org>.

Alex's original description:

Every descriptor in a manifest is interpreted by greybus_new_module().
We call a function to do initialization based on descriptor's type.

Since we know the type of the descriptor at that point, we can pass
to the called function the actual sub-type it needs (i.e., the union
member associated with the type).  This allows those functions to
be slightly simplified, and more focused.

Also change some size variables to have size_t type, and simplify a
few spots further by using sizeof(object) in place of sizeof(type).