staging: greybus: move core include files to include/linux/greybus/

With the goal of moving the core of the greybus code out of staging, the
include files need to be moved to include/linux/greybus.h and
include/linux/greybus/

Cc: Vaibhav Hiremath <hvaibhav.linux@gmail.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Vaibhav Agarwal <vaibhav.sr@gmail.com>
Cc: Rui Miguel Silva <rmfrfs@gmail.com>
Cc: David Lin <dtwlin@gmail.com>
Cc: "Bryan O'Donoghue" <pure.logic@nexus-software.ie>
Cc: greybus-dev@lists.linaro.org
Cc: devel@driverdev.osuosl.org
Acked-by: Mark Greer <mgreer@animalcreek.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Alex Elder <elder@kernel.org>
Link: https://lore.kernel.org/r/20190825055429.18547-8-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: greybus: Remove redundant license text

Now that the SPDX tag is in all greybus files, that identifies the
license in a specific and legally-defined manner. So the extra GPL text
wording can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Vaibhav Hiremath <hvaibhav.linux@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Acked-by: Vaibhav Agarwal <vaibhav.sr@gmail.com>
Acked-by: David Lin <dtwlin@gmail.com>
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Mark Greer <mgreer@animalcreek.com>
Acked-by: Rui Miguel Silva <rmfrfs@gmail.com>
Acked-by: "Bryan O'Donoghue" <pure.logic@nexus-software.ie>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: greybus: add SPDX identifiers to all greybus driver files

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/staging/greybus files files with the correct SPDX
license identifier based on the license text in the file itself. The
SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Vaibhav Hiremath <hvaibhav.linux@gmail.com>
Cc: "Bryan O'Donoghue" <pure.logic@nexus-software.ie>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Acked-by: Vaibhav Agarwal <vaibhav.sr@gmail.com>
Acked-by: David Lin <dtwlin@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Mark Greer <mgreer@animalcreek.com>
Acked-by: Rui Miguel Silva <rmfrfs@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

greybus: audio: apbridgea: Remove GET_TX/RX_DELAY message types

The 'AUDIO_APBRIDGEA_TYPE_GET_TX_DELAY' and
'AUDIO_APBRIDGEA_TYPE_GET_RX_DELAY' message types have been
removed from the AP <-> APBrigdeA Audio Protocol so remove
them from the code. Do not coalesce the message type numbers
to prevent compatibility issues between the AP and APBridgeA.

Testing Done: Played music using a speaker module

Signed-off-by: Mark Greer <mgreer@animalcreek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

greybus: audio: add runtime pm support

Add runtime pm support to audio protocol device class driver.

Testing Done:
- Use white speaker module and check the interface is autosuspended when
it's idle and resumed when playback audio

Signed-off-by: David Lin <dtwlin@google.com>
Signed-off-by: Axel Haslam <ahaslam@baylibre.com>
Reviewed-by: Vaibhav Agarwal <vaibhav.agarwal@linaro.org>
Signed-off-by: Alex Elder <elder@linaro.org>

greybus: audio_apbridgea: fix two return values

Errno -ENOSYS is reserved for missing syscalls, replace it with
-EOPNOTSUPP for the the two stub operations that used it.

Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

greybus: audio: Split start and stop APBridgeA requests

Provide finer-grained control of the audio streaming on APB1 by
splitting the transmit/receive start and stop requests into prepare,
start, stop, and shutdown.

CC: Vaibhav Agarwal <vaibhav.agarwal@linaro.org>
Signed-off-by: Mark Greer <mgreer@animalcreek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

greybus: audio: Register CPorts for specific directions

Currently, it is assumed that all audio data CPorts registered on
APB1 are used for transmitting audio data. That may not always be
true like when a microphone is connected but no speakers. Also,
the current special protocol lacks a way to tell APB1 whether the CPort
being registered is for transmitting, receiving, or both.

Fix by adding a 'direction' field to the register and unregister CPort
requests and define bits indicating which direction (or both) audio
data will go on that CPort.

Signed-off-by: Mark Greer <mgreer@animalcreek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

greybus: audio: Fix sparse warnings

greybus/audio_apbridgea.c:13:5: warning: symbol 'gb_audio_apbridgea_set_config' was not declared. Should it be static?
greybus/audio_apbridgea.c:30:5: warning: symbol 'gb_audio_apbridgea_register_cport' was not declared. Should it be static?
greybus/audio_apbridgea.c:44:5: warning: symbol 'gb_audio_apbridgea_unregister_cport' was not declared. Should it be static?
greybus/audio_apbridgea.c:58:5: warning: symbol 'gb_audio_apbridgea_set_tx_data_size' was not declared. Should it be static?
greybus/audio_apbridgea.c:72:5: warning: symbol 'gb_audio_apbridgea_get_tx_delay' was not declared. Should it be static?
greybus/audio_apbridgea.c:80:5: warning: symbol 'gb_audio_apbridgea_start_tx' was not declared. Should it be static?
greybus/audio_apbridgea.c:94:5: warning: symbol 'gb_audio_apbridgea_stop_tx' was not declared. Should it be static?
greybus/audio_apbridgea.c:106:5: warning: symbol 'gb_audio_apbridgea_set_rx_data_size' was not declared. Should it be static?
greybus/audio_apbridgea.c:120:5: warning: symbol 'gb_audio_apbridgea_get_rx_delay' was not declared. Should it be static?
greybus/audio_apbridgea.c:128:5: warning: symbol 'gb_audio_apbridgea_start_rx' was not declared. Should it be static?
greybus/audio_apbridgea.c:141:5: warning: symbol 'gb_audio_apbridgea_stop_rx' was not declared. Should it be static?
greybus/audio_gb.c:14:5: warning: symbol 'gb_audio_gb_get_topology' was not declared. Should it be static?
greybus/audio_gb.c:48:5: warning: symbol 'gb_audio_gb_get_control' was not declared. Should it be static?
greybus/audio_gb.c:70:5: warning: symbol 'gb_audio_gb_set_control' was not declared. Should it be static?
greybus/audio_gb.c:85:5: warning: symbol 'gb_audio_gb_enable_widget' was not declared. Should it be static?
greybus/audio_gb.c:97:5: warning: symbol 'gb_audio_gb_disable_widget' was not declared. Should it be static?
greybus/audio_gb.c:109:5: warning: symbol 'gb_audio_gb_get_pcm' was not declared. Should it be static?
greybus/audio_gb.c:133:5: warning: symbol 'gb_audio_gb_set_pcm' was not declared. Should it be static?
greybus/audio_gb.c:150:5: warning: symbol 'gb_audio_gb_set_tx_data_size' was not declared. Should it be static?
greybus/audio_gb.c:163:5: warning: symbol 'gb_audio_gb_get_tx_delay' was not declared. Should it be static?
greybus/audio_gb.c:183:5: warning: symbol 'gb_audio_gb_activate_tx' was not declared. Should it be static?
greybus/audio_gb.c:195:5: warning: symbol 'gb_audio_gb_deactivate_tx' was not declared. Should it be static?
greybus/audio_gb.c:207:5: warning: symbol 'gb_audio_gb_set_rx_data_size' was not declared. Should it be static?
greybus/audio_gb.c:220:5: warning: symbol 'gb_audio_gb_get_rx_delay' was not declared. Should it be static?
greybus/audio_gb.c:240:5: warning: symbol 'gb_audio_gb_activate_rx' was not declared. Should it be static?
greybus/audio_gb.c:252:5: warning: symbol 'gb_audio_gb_deactivate_rx' was not declared. Should it be static?

Fix them by including the header that declares the exported routines.

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>

greybus: audio: Add direct audio streaming control for APBridgeA

The latest audio architecture does not stream audio data over the
USB link between the AP and APBridgeA. Instead, audio data is
streamed directly over the I2S link between the two.

To support the Greybus audio driver in setting up the I2S port and
controling packeting/depacketizing of audio data to/from Greybus
audio messages, define a set of commands and their parameters.
These commands and parameters will be placed into a request and sent
over the USB control channel to APBridgeA. A corresponding driver
on APBridgeA will receive and process the requests.

Signed-off-by: Mark Greer <mgreer@animalcreek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>