Alex Elder [Tue, 18 Nov 2014 19:26:42 +0000 (13:26 -0600)]
greybus: allocate space without gbufs
This begins the transition to buffer allocation that does not rely
on the gbuf construct.
The host driver allocation routine will return a pointer to the
buffer to be used, and the caller will be responsible for keeping
track of that pointer, as well as the requested buffer size.
Rename the allocation method to reflect it's no longer tied to a
gbuf.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 19:26:41 +0000 (13:26 -0600)]
greybus: fill in destination data at send time
For ES1 we need to insert the destination CPort id before the data
to be sent over UniPro. Currently this is done at the time the
buffer is created, but there's no need to do so until we're actually
going to send the content of the buffer.
Move the setting of that destination information into submit_gbuf().
Note that this allows us to defer initializing a few other gbuf
fields until after we know the buffer allocation has succeeded.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 19:26:40 +0000 (13:26 -0600)]
greybus: improve data buffer alignment
For ES1 we need to insert the destination CPort id in whatever we
supply for sending over UniPro. Currently we allocate one extra
byte supply the caller with an address that's offset by one from
the beginning of the allocated space.
As a result we always return a poorly-aligned buffer pointer.
Instead, allocate enough space so that we can return a better
aligned buffer to the caller.
Notes:
- It may be that it's more important to supply an aligned
address to the hardware.
- We probably need to be more careful about writing into
these buffers at unaligned offsets anyway. (E.g., writing
a 2-byte value at an odd offset can't be assumed to work.)
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 19:26:39 +0000 (13:26 -0600)]
greybus: prepend cport byte for all gbufs
Treat communication buffers for both inbound and outbound data the
same way, prepending a "destination cport id" byte before the data
in the buffer. Currently this is done only for outbound data
buffers.
This isn't needed for inbound data, but handling it this way
allows the free routine to work without knowing whether the
buffer was used for sending or receiving.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 19:26:38 +0000 (13:26 -0600)]
greybus: fix an allocation flag bug
We allocate message buffers with GFP_KERNEL allocation flags if
possible. However when an incoming request message is received we
can be in interrupt context, so we must use GFP_ATOMIC in that case.
The computation of gfp_flags in gb_operation_message_init() is
wrong. It is needlessly using GFP_ATOMIC when allocating outbound
response buffers. Fix the flawed logic.
Change the name of "data_out" to be "outbound" to be consistent with
usage elsewhere. (Data/messages are "inbound" or "outbound";
requests are "incoming" or "outgoing".)
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 00:08:34 +0000 (18:08 -0600)]
greybus: use null gbuf->transfer_buffer
Make sure gbuf->transfer_buffer gets reset to NULL when the buffer
is freed. We can leverage that to do a little extra error checking.
We'll also use a null transfer buffer in the next patch to indicate
an unused gbuf.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 00:08:33 +0000 (18:08 -0600)]
greybus: move gbuf initialization to caller
Change greybus_alloc_gbuf() so all it does is allocate the gbuf data
structure. Move all of the initialization of the gbuf structure in
the caller. Do the inverse in the caller prior to freeing the gbuf
structure via greybus_free_gbuf(). Use a null gbuf->transfer_buffer
pointer rather than a null gbuf pointer to indicate an unused gbuf.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 00:08:32 +0000 (18:08 -0600)]
greybus: start using struct gb_message
This converts some of the operation code to start leveraging the
new gb_message type. Instead of creating the request and response
gbufs, we initialize (and tear down with a new function) the
request and response message structures.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 00:08:31 +0000 (18:08 -0600)]
greybus: define struct gb_message
A Greybus buffer (gbuf) is a generic buffer used for data transfer
over a Greybus interconnect. We only ever use gbufs in operations,
which always involve exactly two of them. The lifetime of a gbuf is
therefore directly connected to the lifetime of an operation, so
there no real need to manage gbufs separate from operations.
This patch begins the process of removing the gbuf abstraction, on
favor of a new data type, gb_message. The purpose of a gb_message
is--like a gbuf--to represent data to be transferred over Greybus.
However a gb_message is oriented toward the more restrictive way
we do Greybus transfers--as operation messages (either a request or
a response).
This patch simply defines the structure in its initial form, and
defines the request and response fields in a Greybus operation
structure as embedded instances of that type. The gbuf pointer
is defined within the gb_message structure, and as a result lots
of code needs to be tweaked to reference the request and response
gbufs as subfields of the request and response structures.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 00:08:30 +0000 (18:08 -0600)]
greybus: move the definition of struct gbuf
We no longer need struct gbuf defined in "greybus.h". An upcoming
patch will embed a gbuf struct (not a pointer) into the operation
structure, and to do that we'll need the struct defined prior to the
operation. Just move the gbuf definition into "operation.h".
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 00:08:29 +0000 (18:08 -0600)]
greybus: kill gbuf->kref
Since there is only ever one reference to a gbuf, we don't need a
kref to figure out when it can be freed. Get rid of the kref and
its supporting code.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 00:08:28 +0000 (18:08 -0600)]
greybus: kill greybus_{get,put}_gbuf()
These functions are never used, so we can get rid of them.
Since there's no reference-getting function any more, we no
longer need "gbuf_mutex" to avoid racing gets and puts, so
get rid of that too.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
greybus: greybus_manifest.h: update with full list of protocols
The protocol values had gotten out of sync with the Greybus Protocol
specification document, so bring them back into sync by changing a few
values, and adding the missing values.
Alex Elder [Mon, 17 Nov 2014 14:08:45 +0000 (08:08 -0600)]
greybus: get rid of cport_id_map_lock
The only time we get a cport id is when setting up a new connection.
We already have a (coarser-grained) spin lock that's used to protect
the connection lists, and we can use that same lock for protecting
the hd's connection id map.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Mon, 17 Nov 2014 14:08:44 +0000 (08:08 -0600)]
greybus: use a simple list of hd connections
First of all, there's a bug in _gb_hd_connection_insert, which
Viresh found. But pointing out that problem just called attention
to the fact that I have planning to to remove the affected block of
code.
The set of connections associated with a host device is currently
maintained in a red-black tree. The number of connections we're
likely to have is on the order of a hundred, and at least for now
isn't even going to approach that. When this code first went in,
Greg asserted that using a list is speedier than a red-black tree
for smallish numbers of elements (maybe up to a few hundred?).
So this patch just removes the host device's red-black tree of
connections, using a simple list instead.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Mon, 17 Nov 2014 14:08:42 +0000 (08:08 -0600)]
greybus: use gbuf's destination cport id
If the buffer allocated in the ES1 alloc_gbuf_data() routine is for
outbound data, we are getting the destination CPort id from the
connection. Switch to using the copy of the destination cport id
we now have in the gbuf instead.
Check for a valid CPort id there only if we're inserting it into
the buffer.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Mon, 17 Nov 2014 14:08:41 +0000 (08:08 -0600)]
greybus: record a gbuf's destination CPort id
Rather than indicating whether a gbuf is intended for outbound data,
record its destination CPort id. That's what's really needed by
the ES1 host driver. Use CPORT_ID_BAD when the buffer is intended
for inbound data.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Mon, 17 Nov 2014 14:08:39 +0000 (08:08 -0600)]
greybus: clean up gb_connection_operation_recv()
This patch does some cleanup of gb_connection_operation_recv().
- Improve the header comments
- Verify message is big enough for header before interpreting
beginning of the message as a header
- Verify at buffer creation time rather than receive time that
no operation buffer is bigger than the maximum allowed. We
can then compare the incoming data size against the buffer.
- When a response message arrives, record its status in the
operation result, not in the buffer status.
- Record a buffer overflow as an operation error.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Flush out the Greybus UART driver to actually implement greybus
requests. The number of Greybus Protocol operations has been reduced
down to a managable number, and, if you look closely, you will notice it
follows the CDC ACM USB specification, which can drive UART devices
quite well, no need for complex UART state changes, leave all of that
logic up to the firmware, if it wants/needs it.
The Greybus Protocol spec has been updated to match the driver.
TODO: There are 2 requests from the device to the host that need to be
implemented. As this isn't fully hooked up in the Greybus core, that is
not implemented here yet either.
Implement a skeleton for the uevent framework, to be filled in later
when we figure out what type of module "matching" we want to do for
things (connections, interfaces, modules, etc.)
Based on a patch from Viresh Kumar <viresh.kumar@linaro.org>
Viresh Kumar [Fri, 14 Nov 2014 11:55:04 +0000 (17:25 +0530)]
greybus: connection: fix duplicating naming in _gb_hd_connection_insert()
Though this doesn't cause any logical issues as far as the behavior of the
routine is concerned as the local variable would be considered inside the
'while' loop.
But its better not to use the same name for variables at different levels.
Alex Elder [Wed, 12 Nov 2014 21:17:55 +0000 (15:17 -0600)]
greybus: pass operation type on request receive
When an incoming request is received, the operation type is encoded
in the header and is not available in the payload. Add the
operation type as a parameter to the request_recv method so the
request handler knows what to do.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Alex Elder [Wed, 12 Nov 2014 21:17:53 +0000 (15:17 -0600)]
greybus: simplify pending operations tracking
Greg raised the alarm when I first put in the red-black tree for
tracking pending operations. The reality as that we're not likely
to have that many operations in flight at any one time, so the
complexity of the red-black tree is most likely unwarranted. I
already
This pulls out the red-black tree and uses a simple list instead. A
connection maintains two lists of operations. An operation starts
on its connection's operations list. It is moved to the pending
list when its request message is sent. And it is moved back to
the operations list when the response message arrives. It is
removed from whatever list it's in when the operation is destroyed.
We reuse the single operation->links field for both lists.
Only outgoing requests are ever "pending." Incoming requests are
transient--we receive them, process them, send the response, and
then we're done.
Change a few function names so it's clear we're working with the
pending list.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Alex Elder [Wed, 12 Nov 2014 21:17:52 +0000 (15:17 -0600)]
greybus: move timeout out of gb_operation_insert()
Currently, gb_operation_insert() arranges to time out a request if
it takes too long. Move this out of that function and into
gb_operation_request_send(), so we know it's getting set up after
the request has actually be sent.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Alex Elder [Wed, 12 Nov 2014 21:17:51 +0000 (15:17 -0600)]
greybus: fix request timeout bug
This commit changed the timeout behavior for operations: 6a8732e operation: make the timeout a per-operation thing...
It unfortunately left in place some code that was only
appropriate for per-connection timeouts. In particular,
the timer for an operation is currently getting started
only if no existing operations are in flight.
Fix that oversight, and schedule an operation's timer
unconditionally.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Alex Elder [Wed, 12 Nov 2014 21:17:50 +0000 (15:17 -0600)]
greybus: don't assume PAGE_SIZE for URB size
The buffers allocated for CPort URBS are ES1_GBUF_MSG_SIZE bytes.
But usb_fill_bulk_urb() passes PAGE_SIZE as its size. They happen
to be the same, but the code is wrong, so fix it.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Alex Elder [Thu, 6 Nov 2014 13:01:06 +0000 (07:01 -0600)]
greybus: kill gbuf->complete
The gbuf complete method is a callback that allows the creator of a
gbuf to know when all processing on a gbuf is done.
We now only ever allocate gbufs for use in Greybus operations, and
in that case we only ever supply gb_operation_gbuf_complete() as the
completion callback. Furthermore, the only place gbuf->complete()
is called is in gb_operation_recv_work().
Knowing this, we can just call gb_operation_gbuf_complete() directly
from gb_operation_recv_work(), and get rid of the gbuf->complete()
method entirely.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Thu, 6 Nov 2014 13:01:04 +0000 (07:01 -0600)]
greybus: get rid of greybus_gbuf_finished()
All greybus_gbuf_finished() does is call the gbuf's complete method.
Currently, greybus_gbuf_finished() is only ever called in one place,
and that place can call the complete method directly instead. That
allows us to eliminate greybus_gbuf_finished().
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Thu, 6 Nov 2014 13:01:03 +0000 (07:01 -0600)]
greybus: remove gbuf->context
A gbuf now records a pointer to its operation. The only thing ever
stored in a gbuf context pointer is the gbuf's operation. Therefore
there's no longer any need to maintain the context pointer, so get
rid of it.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Thu, 6 Nov 2014 13:01:02 +0000 (07:01 -0600)]
greybus: record gbuf->operation
Currently a gbuf records a pointer to the connection it's associated
with. We now know only use gbufs in operation messages, so we can
point a gbuf at its operation instead. This still gives access to
the connection where needed, but it also will provide all the
context we'll ever need for a gbuf, and this allows us (in the next
patch) to remove the gbuf->context field as well.
So switch to recording in a gbuf the operation rather than the
connection it is associated with.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Thu, 6 Nov 2014 13:01:01 +0000 (07:01 -0600)]
greybus: get rid of gbuf->actual_length
Right now, the actual_length field of a gbuf is only ever assigned,
never used. We now fill gbufs only with operation messages, and
they encode within them the amount of space "actually used" in a
buffer in a request-specific way. As a result, there's no need
for the gbuf->actual_length field, so we can remove it.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Thu, 6 Nov 2014 13:01:00 +0000 (07:01 -0600)]
greybus: kill old cport handler code
Handling of incoming requests has been moved into the Greybus
connection and protocol layers. As a result, the original cport
oriented handler code is no longer used. So get rid of it.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 5 Nov 2014 22:12:55 +0000 (16:12 -0600)]
greybus: add an incoming request receive method
Define a new protocol method intended to handle the receipt of an
incoming operation request. Most protocols have no expected
incoming requests and can leave this null. If a request arrives for
a protocol with no request receive handler an error is reported and
the request fails.
Get rid of the previous fixed array of receive handlers, it's
no longer needed.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 5 Nov 2014 22:12:53 +0000 (16:12 -0600)]
greybus: register preallocated protocols
Set up protocol structures as static objects in each protocol source
file. Pass the address of that in--rather than the protocol id and
version information--to the protocol registration routine. Call a
central routine to register all our pre-defined protocols.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 5 Nov 2014 22:12:51 +0000 (16:12 -0600)]
greybus: count rather than list protocol users
We don't really need a list of protocol users, we can just keep
track of how many there are. Get rid of the list and use a count
instead.
Also, have gb_protocol_get() return the protocol rather than assigning
a passed-in connection pointer's protocol. Make a comparable change
to the gb_protocol_put() interface.
Get rid of gb_protocol_find() (the version that locks), because it
is no longer needed.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 5 Nov 2014 22:12:50 +0000 (16:12 -0600)]
greybus: identify protocol by id *and* version
Right now we only look up a protocol based on its protocol id.
Add support for maintaining a major and minor version as well, and
use them when looking up a protocol.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 5 Nov 2014 22:03:11 +0000 (16:03 -0600)]
greybus: control printing message
There's a message that gets printed in gb_manifest_parse() if excess
descriptors are found in the manifest. This should only be printed
if the parse was successful. If it was not successful it's not
really very helpful.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 5 Nov 2014 22:03:08 +0000 (16:03 -0600)]
greybus: fix a bug in gb_operation_gbuf_complete()
The gbuf completion routine was using the request payload pointers
(which point at the area *past* the message header) rather than the
header. This didn't matter much for now, it was only used in the
error path.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
greybus: connection: fix up error patch logic in gb_connection_create()
Once you have called device_initialize() you have to call put_device()
on the structure to clean it up on an error path, otherwise you will
leak memory.
Alex Elder [Wed, 29 Oct 2014 00:36:00 +0000 (19:36 -0500)]
greybus: introduce protocol abstraction
Define a protocol structure that will allow protocols to be
registered dynamically. For now we just introduce a bookkeeping
data structure. Upcoming patches will move protocol-related methods
into the protocol structure, and will start registering protocol
handlers dynamically.
A list of connections using a given protocol is maintained so we can
tell when a protocol is no longer in use. This may not be necessary
(we could use a kref instead) but it may turn out to be a good way
to clean things up.
The interface is gb_protocol_get() and gb_protocol_put() for a
connection, allowing the protocol to be looked up and the connection
structure to be inserted into its list.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 29 Oct 2014 00:35:59 +0000 (19:35 -0500)]
greybus: use protocol_id for numeric values
Switch to using "protocol_id" to refer to a byte-sized numeric
protocol number. A "protocol" will represent a protocol structure
(created in the next patch).
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 29 Oct 2014 00:35:58 +0000 (19:35 -0500)]
greybus: drop the cport id on error
In gb_connection_create(), if an error occurs adding a connection's
device, the cport id assigned to the AP end of the connection is not
getting freed. Fix that.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Matt Porter [Tue, 28 Oct 2014 14:08:13 +0000 (10:08 -0400)]
greybus: connection: call connection_init hook after setting the handler
In gb_connection_init() we set the connection_handler for each supported
protocol, but we never call the connection_init hook after doing so. This
results in a failure being returned so fix it by calling the connection_init
hook to get a good return and the associated driver initialized.
Signed-off-by: Matt Porter <mporter@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Matt Porter [Tue, 28 Oct 2014 14:08:12 +0000 (10:08 -0400)]
greybus: module: set device_id when initializing an interface
gb_module_interface_init() looks for the interface corresponding
to the supplied interface_id, but fails to configure the
device_id that goes with it. This results in a set route command
being set with an uninitialized and bogus value. Fix it.
Signed-off-by: Matt Porter <mporter@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
We aren't using an id_table for "drivers" at this moment, as the whole
driver model interaction is under heavy rework. So remove these for now
to keep things easier to understand for future patches.
Alex Elder [Mon, 27 Oct 2014 11:04:30 +0000 (06:04 -0500)]
greybus: begin abstracting connection operations
This is part 1 of abstracting the connection operations into a set
of methods. This will avoid some big switch statements, but more
importantly this will be needed for supporting multiple versions of
each protocol.
For now only two methods are defined. The init method is used
to set up the device (or whatever the CPort represents) and the exit
method tears it down. There may need to be additional operations
added in the future, and once versioning is used we might stash
the version number in this structure as well.
The next patch adds dynamic registratration of these protocol
handlers, and will do away with the switch statement now found
in gb_connection_init().
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
greybus: module: remove unneeded XXX comment about module id values
We do properly check for duplicate module ids, as fixed in 008d85d90ae1ab31f1f7b80f245f6ee2eb5aed49 "module: don't create duplicate
module ids", so remove the XXX marker.
greybus: FIXME/XXX removals: We have proper reference counting now
Now that we have proper reference counting for modules, interfaces, and
connections, no need to worry about grabbing a pointer to your "parent"
structure, all is good.