Make kmalloc for the send buffer a one time alloc based on the MTU for
a given greybus link.

The write_room for an gb_operation_sync then will be the size of the
buffer we use for a single operation.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

gb_operation_sync returns 0 on success but the calling function
expects the number of bytes written on success or a negative errno
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

For each new UART connection we need to do a tty_port_init else
we'll crash when trying to access the tty mutex later on.
Base the TTY major/minor numbers on non-zero values.
Supply an empty operations structure for the newly regitered port.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Arbitrary number 255 is both not aligned and probably too big.
Move the UART count down to 16 which is still large but, more realistic.
8 may be too few for future testing setups, 16 should accomodate any.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Update tabs and naming of structures to match the naming used in the greybus
specification more closely.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

gbsim depends on the structures and defines in greybus_protocols.h
generally in order to simulate firmware. Move UART defines into this
header to facilitate.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

If alloc minor is error, gb_tty should free.
Signed-off-by: Phong Tran <tranmanphong@gmail.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Because of the missing '\n', this is how the output of reading endo
sysfs files looks:

root# cat /sys/bus/greybus/devices/endo/id
0x4755root#

Fix it by including \n to the end of the printed string.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Add Greybus GPIO IRQ-type defines rather than rely on the current
Linux implementation.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Remove unused debounce define from protocol header.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

With the Endo "id" attribute in place, there's no need to encode
the ID of an Endo in its sysfs path.  So get rid of it.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

This commit:
    7e761e2 endo: rework some attributes
added a new "endo_id" attribute, located under a new "Endo"
directory in sysfs.  The resulting path looks like:
    Documentation/sysfs/endo-TYPE/Endo/endo_id
There's no need to have a separate "Endo" subdirectory to contain
Endo-specific attributes.

That commit also added "svc_" to some other paths related to the
SVC, like:
    Documentation/sysfs/endo-TYPE/SVC/svc_version
The additional "svc_" is redundant.

This patch retouches those paths a bit, mainly to remove some
redundancy.  It also makes the pathname components all lower case.
As a result, the above two paths now look like:
    Documentation/sysfs/endo-TYPE/id
    Documentation/sysfs/endo-TYPE/svc/version

All other Endo sysfs files are updated similarly.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Impose a few editorial conventions on the Greybus-related sysfs
files under "Documentation".
    - Capitalize "Endo" (except in path names)
    - Capitalize "ID" (except in path names)
    - Use "..." to indicate unspecified path components (because
      ".." means something else).
    - Add the "0x" prior to the "XXXX" representing the Endo ID.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Update the files documenting Greybus-related sysfs files under
Documentation/ to reflect the addition of the two recently-added
Endo attributes.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

This is not a kernel module. It should not use
the module license macro.
Signed-off-by: Phong Tran <tranmanphong@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

This macro should be DATA not MGMT.
Signed-off-by: Phong Tran <tranmanphong@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

I neglected to update the "#ifndef/#define" when I renamed
"greybus_protocols.h".  Fix that.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Update the remaining operation types now that the ack operation is gone
to avoid leaving a hole in the type definitions.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Change to gb_gpbridge_protocol_driver for
making the consitent with other drivers.
Signed-off-by: Phong Tran <tranmanphong@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

data of hotplug request should exchange to native
CPU format before assignment.
Signed-off-by: Phong Tran <tranmanphong@gmail.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The current interrupt implementation uses the simple irq-flow handler,
which means that the interrupt subsystem makes no irq-chip callbacks
when handling an interrupt. Specifically, no end-of-interrupt message is
sent when the threaded handler has run. This means that we may currently
re-enable an interrupt before it has been serviced (i.e. the irq-event
operation may complete before the threaded handler has run).

The simple flow handler also silently drops a second interrupt arriving
while a handler is running. This means that we may lose a second edge
interrupt with the current firmware.

Switch to a new one-shot interrupt protocol, where the primary handler
(firmware) always masks and acks an interrupt before sending an event to
the AP. The AP is responsible for unmasking the interrupt when it has
been handled. By having the firmware ack an edge interrupt before
sending the event, a second edge interrupt will no longer get lost.

This one-shot protocol can be implemented in the kernel by using the
level irq-flow handler, one-shot interrupts with threaded handlers and
bus-lock synchronisation for slow buses. Note that the same flow handler
is used for both edge and level interrupts.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The irq-chip callbacks are made in atomic context where we must not do
any synchronous greybus operations.

Fix the current gpio-interrupt implementation by using the bus-lock
functionality provided by the irq subsystem.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Rename irq mask and unmask functions to match the callback names.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Use irq_find_mapping directly rather than go through the legacy gpio
interface.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Use generic_handle_irq_desc rather than call a hardcoded irq-flow
handler directly.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Remove unused irq-ack operation, which has never been called and does
not make sense for message-signalled interrupts over slow buses.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Fix debugfs output by removing the unimplemented, custom dbg_show
callback. The default implementation is perfectly sufficient.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Add support for incoming, unidirectional operations where the sender of
a request does not care about a response.

Unidirectional operations have an operation id of 0.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

This patch adds support for the Greybus SVC protocol.  We may want
to rearrange protocol numbers at some point, since this is a pretty
fundamental protocol.

Note:  It has only been compile tested; no SVC CPorts have yet been
defined, so this code is not yet exercised.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Update the copyright statements for recently-modified source files.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The Greybus audio source files included no copyright statements.
Add them.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Currently, the data structure representing an Endo is set up at the
time a host device gets created.  This is too early.

Once the control infrastructure is in place, there's no sense in
setting up the Endo utnil after we have heard from the SVC via a
probe operation on our control CPort.  And even then, there's
no real point until we've successfully authenticated with the SVC,
which will be indicated by the arrival of the Control protocol
"connected" operation request notifying us that our SVC CPort
is operational.

In addition to this logical argument, we also can't actually
receive any messages on the Control CPort until the host device
is set up and ready to receive messages.  At the point we're
currently setting up the Endo data structure, that has not yet
been done.

Define a new exported function greybus_endo_setup(), which will
be used (for now) as the entry point for setting up the Endo
data structure.  Arrange to call it in the host USB driver
probe method, *after* we are set up for handling messages.

Note: Once the control protocol has been implemented, this function
may no longer need to be exported.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The AP resides in a particular position on an Endo, which is
identified by an interface ID.  (For now we'll assume the AP uses
just one interface.)  Record the this AP interface ID when creating
an Endo.  Add a sysfs attribute to display it as well.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The SVC is not the same as the Endo.  There are some attributes
(such as the Endo ID) that are independent of attributes of
the SVC (like its version).

The current "Endo attributes" are really SVC attributes.
Rename a few functions and variables to reflect that.

Add a new attribute group for Endo-specific attributes, and
populate it with the Endo ID.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The maximum interface id on an Endo is the result of a non-trivial
calculation.  It'll be needed for an upcoming patch, so create a
macro to compute it.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The file "gpbridge.h" is now used as a single place to define
all protocol message structures.  These protocols are not
necessarily related to the GP bridge, so the name of the
file is misleading.

Rename it "greybus_protocols.h".
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Avoid the need for all the source files to include "gpbridge.h"
by just having "greybus.h" include it.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Return a pointer-coded error from greybus_create_hd() rather
than NULL in the event an error occurs.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>