samples/rpmsg: Introduce a module parameter for message count

The current rpmsg_client_sample uses a fixed number of messages to
be sent to each instance. This is currently set at 100. Introduce
an optional module parameter 'count' so that the number of messages
to be exchanged can be made flexible.

Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

samples/rpmsg: Replace print_hex_dump() with print_hex_dump_debug()

Replace the raw print_hex_dump() call in the rpmsg_sample_cb() function
with the equivalent print_hex_dump_debug() better suited for dynamic
debug. This switch allows flexibility of controlling this trace through
dynamic debug when enabled.

Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282

Based on 1 normalized pattern(s):

this software is licensed under the terms of the gnu general public
license version 2 as published by the free software foundation and
may be copied distributed and modified under those terms this
program is distributed in the hope that it will be useful but
without any warranty without even the implied warranty of
merchantability or fitness for a particular purpose see the gnu
general public license for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 285 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

rpmsg: Allow callback to return errors

Some rpmsg backends support holding on to and redelivering messages upon
failed handling of them, so provide a way for the callback to report and
error and allow the backends to handle this.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

rpmsg: Clean up rpmsg device vs channel naming

The rpmsg device representing struct is called rpmsg_channel and the
variable name used throughout is rpdev, with the communication happening
on endpoints it's clearer to just call this a "device" in a public API.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

rpmsg: rpmsg_send() operations takes rpmsg_endpoint

The rpmsg_send() operations has been taking a rpmsg_device, but this
forces users of secondary rpmsg_endpoints to use the rpmsg_sendto()
interface - by extracting source and destination from the given data
structures. If we instead pass the rpmsg_endpoint to these functions a
service can use rpmsg_sendto() to respond to messages, even on secondary
endpoints.

In addition this would allow us to support operations on multiple
channels in future backends that does not support off-channel
operations.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

samples/rpmsg: add support for multiple instances

The current rpmsg_client_sample is a very simple example and
is not designed to handle multiple instances. Add support for
multiple instances, so that the same number of pings are sent
to each instance. The instances can be on one or multiple
remote processors.

Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

rpmsg: use module_rpmsg_driver in existing drivers and examples

Existing drivers and examples are updated to use the
module_rpmsg_driver helper macro.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

rpmsg: drop owner assignment from rpmsg_drivers

An rpmsg_driver does not need to set an owner, it will be populated by
the driver core.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

misc: remove __dev* attributes.

CONFIG_HOTPLUG is going away as an option. As a result, the __dev*
markings need to be removed.

This change removes the last of the __dev* markings from the kernel from
a variety of different, tiny, places.

Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.

Cc: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

samples/rpmsg: add an rpmsg driver sample

Add an rpmsg driver sample, which demonstrates how to communicate with
an AMP-configured remote processor over the rpmsg bus.

Note how once probed, the driver can immediately start sending messages
using the rpmsg_send() API, without having to worry about creating endpoints
or allocating rpmsg addresses: all that work is done by the rpmsg bus,
and the required information is already embedded in the rpmsg channel
that the driver is probed with.

In this sample, the driver simply sends a "Hello World!" message to the remote
processor repeatedly.

Designed with Brian Swetland <swetland@google.com>.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Brian Swetland <swetland@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg KH <greg@kroah.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>