This patch adds a number of USB Vendor commands to es2.c to enable TimeSync
in the bridge.

Adds:
- es2.c::timesync_enable(u8 count, u64 frame_time, u32 strobe_delay,
			 u32 refclk);
  Commands APBx to enable timers and clocks to track a pulse-train of
  incoming TIME_SYNC strobes with strobe_delay microseconds between each.
  Provides the reference clock the AP is using to track FrameTime. It is
  the responsibility of APBx to adequately track the FrameTime based on
  the indicated AP refclk. Once this command has succeeded APBx may not
  transition to a low-power state were FrameTime counters stop.

  This function is initiated from the timesync worker thread logic when
  re-synchronizing frame-time throughout the system.

  TimeSync is at this time enabled for all APBx active in the system i.e.
  currently APB2 will not receive TimeSync commands until it becomes a
  registered host-device in Greybus.

- es2.c::timesync_disable(void)
  Commands APBx to discontinue tracking of FrameTime. After this operation
  completes APBx may transition to a low-power state where timer-clocks
  stop operating.

- es2.c::timesync_authoritative(u64 *frame_time)
  Provides an authoritative time for each TIME_SYNC strobe to APBx.
  APBx must align its local FrameTime to the authoritative clock.

- es2.c::timesync_get_last_event(u64 *frame_time)
  Returns the FrameTime at the last SVC_TIMESYNC_PING to the AP Module.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

This patch adds a new 'firmware' folder in Documentation, which contains
two files:

- firmware-management: This describes the userspace interface for
  interacting with firmware-management bundle.

- firmware.c: Sample application to test firmware load for Interface
  Firmware and firmware updates to Backend Interface Firmware.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Jun Li <li_jun@projectara.com>
Tested-by: Karthik Ravi Shankar <karthikrs@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

This patch adds SPI Protocol support to firmware core, which allows the
AP to access an SPI flash memory present with an Interface.

Tested by using the API from fw-management driver and compiling it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The fw-management driver rightly destroys the char device on
connection-exit, but that doesn't guarantee that all of the users of the
device are gone.

Userspace may still be holding file-descriptor of the char device and
can initiate new ioctl operations. And that *will* lead to kernel crash.

To avoid this issue, manage struct users with kref, manage a list of
'struct fw-mgmt' and start using the structure only after getting its
kref incremented.

The important part is the routine get_fw_mgmt(), which increments the
reference to the struct before returning it to the caller. The list of
fw-mgmt structs in protected with a mutex to avoid any races around
that.

The kref is incremented once the char device is opened and dropped only
when it is closed.
Reported-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Once the interface firmware is loaded successfully to a module,
userspace can ask it to mode switch to the newly loaded firmware.

This patch provides a new ioctl to initiate mode switch.

Userspace can initiate a mode switch if it has previously loaded the
interface firmware successfully, otherwise the firmware core rejects it.

Also, once the mode-switch is initiated, disallow any more interactions
from the userspace.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Karthik Ravi Shankar <karthikrs@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

This patch adds Firmware Management Protocol support to firmware core,
which allows the AP to manage firmware on an Interface.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Jun Li <li_jun@projectara.com>
Tested-by: Karthik Ravi Shankar <karthikrs@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

'make check' correctly complains that this should be static, so make it
so.
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

spilib can be used by multiple bridge drivers implementing different
bundle classes. Separate out bridged PHY bundle drivers parts.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Rui Miguel Silva <rui.silva@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

This patch restructures spi.c as spilib core, so that the same logic can
be reused for SPI connections implemented as part of different bundle
types. This is required for Firmware Management Bundle.

Note that the 'struct gb_protocol' and its callback aren't moved to
a separate file in this commit to make its reviews easier. That will be
done by a following patch.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Rui Miguel Silva <rui.silva@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

These protocols are managed under the bridged PHY class and doesn't need
protocol specific classes anymore.

Remove their entries from gb_gpbridge_id_table array and remove the now
unused macro's and mark their values as unused.

Tested on EVT 1.5 with generic-test module.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Sandeep Patil <sspatil@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

gb_gpbridge_builtin_driver() isn't used anymore, remove it.

Tested on EVT 1.5 by inserting GP test module, all the devices were
enumerated correctly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Rename gb-phy.ko module as gb-gpbridge.ko.

Tested on EVT 1.5 by inserting GP test module, all the devices were
enumerated correctly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Create separate module for usb gpbridge driver.

Tested on EVT 1.5 by inserting GP test module, all the devices were
enumerated correctly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Create separate module for uart gpbridge driver.

Tested on EVT 1.5 by inserting GP test module, all the devices were
enumerated correctly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Create separate module for spi gpbridge driver.

Tested on EVT 1.5 by inserting GP test module, all the devices were
enumerated correctly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Create separate module for sdio gpbridge driver.

Tested on EVT 1.5 by inserting GP test module, all the devices were
enumerated correctly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Create separate module for pwm gpbridge driver.

Tested on EVT 1.5 by inserting GP test module, all the devices were
enumerated correctly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Create separate module for i2c gpbridge driver.

Tested on EVT 1.5 by inserting GP test module, all the devices were
enumerated correctly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Create separate module for gpio gpbridge driver.

Tested on EVT 1.5 by inserting GP test module, all the devices were
enumerated correctly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Create module_gpbridge_driver() for registering gpbridge module drivers.

Tested on EVT 1.5 by inserting GP test module, all the devices were
enumerated correctly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

In order to separate protocol specific drivers into their own modules,
some of the gpbridge routines need to be exported.

Tested on EVT 1.5 by inserting GP test module, all the devices were
enumerated correctly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The count field is redundant and unused. Drop it from the control
timesync_authoritative command.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

gb_control_timesync_get_last_event() sends a request asking for the
FrameTime at the last SVC strobe event. The responding entity returns the
FrameTime in the response phase of the request. Performing this operation
to an Interface after previously:

1. Synchronizing time using timesync-enable/timesync-authoritative
2. Sending an SVC_TIMESYNC_PING

will return the FrameTime of the responding entity at the SVC-ping. If
this command is sent before synchronization has been initiated or
successfully completed the responding entity should return an error
code.

- control.c::gb_control_timesync_get_last_event(u64 *frame_time)
  Returns the FrameTime at the last SVC_TIMESYNC_PING to the AP Module.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Reviewed-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Reviewed-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Simple addition of the TimeSync commands defined in the specification.

Adds:
- svc.c::timesync_enable(u8 count, u64 frame_time, u32 strobe_delay,
                         u32 refclk)
  Commands the SVC to initiate count TimeSync strobe pulses with
  strobe_delay microseconds delay between each strobe to the specified
  bit-mask of Interface IDs indicated in a previous
  timesync_wake_pins_acquire command. The frame_time parameter indicates
  the initial time the SVC should base the first strobe from. The refclk
  parameter indicates the APs clock rate, the SVC should ensure its own
  clock ticks at this rate. Once enabled the SVC may not enter a low-power
  mode which will result in the reference timer used to track time
  switching off. The SVC will capture the authoritative FrameTime at each
  strobe and store these values for later propagation to the AP with the
  timesync_authoritative request.

- svc.c::timesync_disable(void)
  Commands the SVC to immediately halt TimeSync logic. This will allow
  the SVC to transition into low-power modes where the reference timer
  being used for TimeSync may switch off.

- svc.c::timesync_authoritative(u64 *frame_time)
  Used by the AP Module to ask the SVC for the authoritative FrameTime
  as captured at each TimeSync strobe.

- svc.c::timesync_ping(u64 *frame_time)
  Used by the AP Module to command the SVC to initiate a single strobe on
  a specified bit-mask of Interface IDs communicated in a previous
  timesync_wake_pins_acquire command. SVC will latch the FrameTime on the
  rising edge of the outbound pulse and will return the FrameTime to the
  AP Module in the response phase of the greybus transaction.

- svc::timesync_wake_pins_acquire(u32 strobe_mask)
  Used by the AP to tell the SVC to set a bit-mask of wake lines associated
  with a bit-mask of Interface IDs to a known initial state prior to the
  SVC generating a TimeSync related pulse such as timesync-enable or
  timesync-ping.

- svc::timesync_wake_pins_release(void)
  Used by the AP to tell the SVC to release all wake-detect lines in the
  timesync active state as previously specified in the
  timesync_wake_pins_acquire operation.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Reviewed-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The header calls out the license to be GPL v2, while the module declares
itself as "GPL"

Testing Done: Trivial
Signed-off-by: Sandeep Patil <sspatil@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

The uevent vars now include module, interface, greybus_id,
bundle id, class and gpbridge device specific properties.

This make it consistent with how we are reporting uevents for
all other greybus devices.

Testing Done:
Tested by reading uevent from gpbridge devices that enumerate
using gpb module
Signed-off-by: Sandeep Patil <sspatil@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Making gpb device ids consistent with all other devices on
greybus

Testing Done:
Tested using gpb module to make sure the first gpbX/ device
starts with 1.
Signed-off-by: Sandeep Patil <sspatil@google.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Right now, there is no way to know the device type of gpbridge
(bridged-phy) devices in userspace. So, add that.

Testing Done:
Tested by reading the 'uevent' for gpb device of gpbridge
module
Signed-off-by: Sandeep Patil <sspatil@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Now that core supports offloaded connections, we can remove the hack
that was used to setup the data connection.

Note that offloaded-resource management may need to be refined later,
but the current minimal implementation is enough to allow core to manage
the connections (e.g. needed for proper connection tear down and power
management).

This will also allow the camera driver to be converted to a bundle
driver.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Firmware currently lacks a representation of the offloaded CDSI
connections and connected requests sent for these ports therefore fails.

Add a temporary work-around until this has been resolved in firmware.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Use the new CPort-allocation callbacks to allow for rudimentary resource
management of the CDSI CPorts.

How to manage offloaded resources in a generic fashion is yet to be
determined, but this minimal implementation will allow core to manage
the camera data connection so that the current camera-driver hacks can
be removed. This is specifically required to be able to implement proper
connection closing and for power management.

Note that the CDSI CPorts can not (currently) be reset through the
USB vendor request.
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>

Move handling of CPort-reset exceptions to the reset handler.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Generalise CPort allocation by allowing host-device drivers to override
the default implementation.

Also pass the connection flags down the stack as such information is
needed for proper CPort allocation. Specifically, this will initially be
used to allow the camera driver to allocate the dedicated CDSI CPorts.
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>

Clean up the CDSI CPort reservation by adding a host-device helper and
CPort defines.
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>

Make sure to return -ENODEV when the expected endpoints are missing and
stop relying on a default error.
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>

Move host-device CPort allocation to the host-device code.

Proper CPort allocation requires knowledge of the hardware and must be
handled by the host-device driver. This is an intermediate step that
moves the generic CPort-allocation code to the host-device code.
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>

Mark the data-connection as offloaded, that is, under control of the
host device (AP-bridge).

This prevents messages from being sent from or forwarded to the AP.
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>

Add helper for creating offloaded connection.

This can later be extended to support more elaborate resource
management.

Also fix a minor white space issue.
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>

Add an offloaded connection flag, which is used to mark a connection as
offloaded and prevent drivers from initiating operation over it.

This will be used for the audio and camera data connections.
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>

Add a no-flow-control connection flag, which is set for connection that
should not have any flow-control feature enabled.

This flag is specifically set for all connections to the legacy ES3
bootrom, and will also be used by the camera driver eventually.
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>