I did this recently for the endo id allocation code.

It's clearer now that the allocation of a CPort ID to use for
the AP side of a connection is not very complicated, and it
happens in a pretty controlled environment.  The functions that
abstract getting and releasing those ids don't really add that
much value.

This patch removes gb_connection_hd_cport_id_alloc() and
gb_connection_hd_cport_id_free(), and just open-codes their
activity in the few places they are called.

It is obvious now that the CPort ID allocation isn't done in
atomic context, so we can change the ida_simple_get() call to
use GFP_KERNEL.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Although a connection records its protocol id when it gets
created, its protocol handler doesn't actually get assigned
until gb_connection_bind_protocol() is called.

In gb_connection_create() there are some error paths in
which a reference to the connection's protocol is released
before the protocol handler has been associated with the
connection.

Get rid of those calls.

As a result, we will never pass a null protocol pointer to
gb_protocol_put().  Add a precautionary warning in that
function in the event that ever occurs.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

When an error occurs in the device_add() call for a connection, the
device reference is dropped as required.  Because that's the device's
only reference, that will also lead to gb_connection_release() being
called, which frees the connection structure.

Right now we're then making an extra request to free the connection,
which is wrong.  Fix that.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

There is lack of unregister and free the tty driver.
This patch fixes it.
Signed-off-by: Phong Tran <tranmanphong@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

__init does not belong in a .h file, as it does not do anything there,
so remove all instances of it.
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

WARNING: /home/viresh/work/repos/ara/greybus/greybus.o(.init.text+0xb8):
Section mismatch in reference from the function init_module() to the
function .exit.text:gb_endo_exit()

The function __init init_module() references
a function __exit gb_endo_exit().

Fix it by removing __exit from endo_exit().

Fixes: cf64356c5151 ("endo: define endo_init() and endo_exit()")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Check at connection creation time for an attempt to create a
connection with an interface CPort ID that's the same as one that's
already been created.

Define a new helper function to look for such a duplicate.  The
check for a duplicate is only performed at initialization time,
and CPorts are initialized serially for each bundle, so there's
no need to acquire the list lock for this search.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Check at bundle creation time to ensure we're not creating a bundle
with an id that's the same as one that's already been created.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Rework the the code that parses the manifest for bundles so it only
touches each manifest descriptor once.  (Previously the list was
scanned from the beginning repeatedly until all bundles were found.)
Shorten the name of the descriptor variable, to avoid line wrap.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Rework the the code that parses the manifest for CPorts associated
with a bundle so it only touches each manifest descriptor once.
(Previously the list was scanned from the beginning repeatedly
until all bundle CPorts were found.)  Shorten the name of the
descriptor variable, to avoid line wrap.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

An initialized bundle structure contains a pointer to its
interface.  Because of this there's no need to provide
the interface pointer to gb_manifest_parse_cports().  This
also precludes the possibility of passing a bad interface
pointer.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

This patch incorporates some very small cleanups to "manifest.c":
    - Rearrange code a bit in gb_manifest_parse() that ensures a
      manifest is big enough to hold a header.  If the manifest is
      exactly the size of a header, the error reported will now be
      "...must have 1 interface..." rather than "short manifest".
    - Fix the function comment for gb_manifest_parse_cports().
    - Use "an interface," not "a interface," and don't capitalize.
    - Delete some braces when getting interface product string.
    - A few other minor changes to comments and white space.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Recently code was added (back) to assign a unique id to each
endo, so satisfy uniqueness requirements of the Linux device
subsystem.  An ID allocator is used to manage the space of IDs.

Now that we have gb_endo_init(), we can initialize the map there,
and fully hide the ID map within "endo.c".

The original functions gb_endo_id_alloc() and gb_endo_id_free()
provided a nice abstract interface, but the direct ID allocation
calls are quite simple, so just call them directly.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Define init and exit functions to do one-time setup and teardown
of endo-related functionality.  Currently they're place holders;
the next patch will populate them.

Note that we now call gb_operation_exit() from gb_init(), so
we can no longer mark that function with __exit.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The top-level functions gb_init() and gb_exit() are tagged with
__init and __exit, respectively.  These functions call a few
other functions that are similarly used only at initialization
and termination time.  So mark those functions accordingly.

Note that, because gb_ap_exit() and gb_debugfs_cleanup()
are called by gb_init() in error paths, these functions
cannot be declared with the __exit attribute.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

There's no need to include anything other than "greybus.h" in
"connection.c".  Same thing in "core.c" and "manifest.c" and
"svc.c".  Some files need headers included, but most come along
with "greybus.h".
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The sample count placed in Greybus I2S audio messages should be
reset every time a new audio stream is set up.  However, the
current code does not do the reset so make it so it does.
Signed-off-by: Mark Greer <mgreer@animalcreek.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The firmware is having a hard time with 4k buffers and memory
allocation, so decrease the size on the host side to 2k.  Also move away
from using PAGE_SIZE to denote 4k as that's not the case on all
architectures, and someone, someday, might get a rude surprise.
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The unregister_chrdev_region() does twice here.
The chrdev region was unregistered
inside tty_unregister_driver().
Signed-off-by: Phong Tran <tranmanphong@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

There is a sparse warning. The endo id map is also
used in endo.c. Should define in endo.h
Signed-off-by: Phong Tran <tranmanphong@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Normally, its a good practice to free resources in the reverse order in
which they are allocated, so that all the dependencies can be sorted out
properly.

This is true while creating/destroying devices as well. For example
consider this scenario (I faced a crash with control protocol due to
this). For a new module, we will first create a bundle+connection for
the control cport and then create other bundles/connections after
parsing manifest.

And while destroying interface on module hot unplug, we are removing the
devices in the order they are added. And so the bundle/connection for
the control cport are destroyed first. But, control cport was still
required while destroying other bundles/connections.

To solve this problem, lets destroy the resources in the reverse order
in which they are added.
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>

Provide a little more information in two pr_err() calls.
Also enclose a reported condition in parentheses, to match
the style used everywhere else in the file.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Rename greybus_deregister() to be greybus_deregister_driver(), so
its name mirrors the greybus_register_driver() function it matches.
Define greybus_deregister() to be a trivial macro.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

In gb_uart_request_recv(), the receive data size is in little-endian
format.  Do the proper byte swapping of that value before using it.
Found by "make check".
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Give gb_connection_hd_find() static scope; it's never used
outside "connection.c".
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The SVC protocol driver should have been defined as a basic
Greybus protocol driver, not a GP Bridge protocol driver.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Prefix module-id with endo-id to uniquely identify it for the entire
kernel.
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Currently we name the endo device as "endo". And it shows up with the
same name in sysfs directory: /sys/bus/greybus/devices/.

But each device in kernel should be represented by a unique id in
kernel, and "endo" isn't unique.

Lets generate unique ids for endo devices. The ida mechanism for
allocating ids may be overkill but it works.
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

This isn't unique just for the bundle but the complete interface. Its
wrong to call it bundle_cport_id. Lets name it intf_cport_id to make
things clear.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

'buffer' isn't used in this function, remove it.
Reviewed-by: Johan Hovold <johan@hovoldconsulting.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Use defines for the data format command.
Tidy up naming of gb_tty variables.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

gb_uart_request_recv job in life is to process unsolicited greybus
mesages from the UART.
Hook the incoming UART data and pass to the TTY layer.
Line-state changes still TBD.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

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>