Alex Elder [Thu, 20 Nov 2014 22:09:13 +0000 (16:09 -0600)]
greybus: have greybus allocate its own buffers
Rather than having the host driver allocate the buffers that the
Greybus core uses to hold its data for sending or receiving, have
the host driver define what it requires those buffers to look like.
Two constraints define what the host driver requires: the maximum
number of bytes that the host device can send in a single request;
and a statement of the "headroom" that needs to be present for
use by the host device.
The direct description of the headroom is that it's the extra byte
the host device needs at the beginning of the "data" portion of
the buffer so the ES1 driver can insert the destination CPort id.
But more generally, the host driver could put other data in there
as well.
By stating these two parameters, Greybus can allocate the buffers it
uses by itself. The host driver still allocates the buffers it uses
for receiving data--the content of those are copied as needed into
Greybus buffers when data arrives.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Thu, 20 Nov 2014 21:37:07 +0000 (15:37 -0600)]
greybus: complete overflow responses
If a response arrives for an operation request and the allotted
buffer isn't big enough we report the error, but we don't finish
processing the response.
Instead, set the operation result, but then finish processing
the response (no different from any other operation error).
This will allow the normal completion handling to occur for
this error case.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Thu, 20 Nov 2014 21:37:06 +0000 (15:37 -0600)]
greybus: fix a timeout race
Whenever we send a request message we start a timer to ensure the
we don't wait too long for the matching response to arrive.
Currently we set up the timeout *after* sending the message, but
that is subject to a race--the response could arrive (and the
timeout prematurely disabled) before the timeout is even set up.
Set up the timeout before sending the message.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 19 Nov 2014 23:55:05 +0000 (17:55 -0600)]
greybus: remove status from all responses
This is a pervasive change, but not really a big one. However:
============== Pay attention to this ==============
If you're doing any testing with "gbsim" you need to
update that program in sync with this change, because
it changes the protocol used between them.
============== Pay attention to this ==============
The status of a request is now recorded in the header of a response
message. The previous patch put that header status byte in place,
and this one removes the status byte from all the response
messages.
And finally, since we're modifying all these files anyway...
Use gb_operation_status_map() to come up with a return code
to use, given an operation response. Right now most errors
simply result in -EIO getting returned.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 19 Nov 2014 23:55:03 +0000 (17:55 -0600)]
greybus: send operation result in response message header
Define a result byte in an operation response message header.
All the protocols now define the mandatory status as the first
byte in their response message. Assume that, for the moment,
and save that value into the header result field (until we can
get the simulator set up to handle the new protocol).
Record the result from the response header as the result of the
overall operation.
Start enforcing the rule that we ignore all response payload (in
fact, the entire message) if we see a non-zero result value.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 19 Nov 2014 23:55:02 +0000 (17:55 -0600)]
greybus: distinguish incoming from outgoing requests
When we remove the mandatory status byte from response messages we
will no longer be able to use a zero-sized response to indicate
an operation is to be used for an incoming request.
Define a new function gb_operation_create_incoming() to be used
for incoming operations. Change (and rename) gb_operation_create()
to be a helper that takes a Boolean to indicate which type is to be
created, and use a simple wrapper to expose the outgoing operation
creation routine.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 19 Nov 2014 23:55:01 +0000 (17:55 -0600)]
greybus: get rid of uart request_operation()
In "uart-gb.c", request_operation() function is only used by
get_version(). Since it's not reused, it probably subtracts
rather than adds value. So just incorporate what it does
into get_version() and get rid of request_operation().
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
This hooks up throttle/unthrottle to properly toggle the RTS line or do
XON/XOFF if that is how the port is set up.
Note, if the UART itself can handle XON/XOFF, we would need to send the
correct character down to it, to have the firmware in the device set up
the chip to use it automatically when needed. The odds of someone
wanting to use this type of flow control is slim, so this isn't
implemented at this point in time.
Also fill in a few more fields in the get_serial_info ioctl, to make
tools like stty(1) happier.
Alex Elder [Wed, 19 Nov 2014 22:29:14 +0000 (16:29 -0600)]
greybus: fix battery_operation()
This patch fixes some problems with the battery protocol driver.
First, when gb_operation_create() is called, it creates buffers of
the requested sizes to hold the operation request and response
messages. There is therefore no reason to allocate a local response
buffer. By the time the (synchronous) gb_operation_request_send()
call returns, the operation response buffer will have been filled in.
(In addition, the content of local_response was not being filled
before its contents were used...)
Next, all the message structures are misnamed. The structures that
are defined are all the content of operation response messages (not
request messages). So this changes all the types names to properly
reflect their role.
All the local variables using these types are similarly renamed.
I added a new type, gb_generic_battery_response, to be used for
casting the fake_response used in battery_operation().
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 19 Nov 2014 18:27:17 +0000 (12:27 -0600)]
greybus: refactor gb_connection_recv()
Define two helper functions to break down handling of a received
message. One is used to handle receiving an incoming request
message, the other for a response message.
Three other changes are made:
- We verify message size recorded in the message header does not
exceed the amount of data that's arriving.
- We no longer warn if a request' recorded message size differs
from the number of bytes that have arrived.
- We now record the operation id for an incoming request.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 19 Nov 2014 18:27:16 +0000 (12:27 -0600)]
greybus: use "operation_id" for certain values
A message header contains a field "id" that is an operation id.
Since the field doesn't identify the message itself, rename this
field so it's clearer what it's referring to.
Similarly gb_pending_operation_find() has a parameter "id" that
is really an operation id, so rename that as well.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 19 Nov 2014 18:27:14 +0000 (12:27 -0600)]
greybus: tidy up svc_in_callback() and cport_in_callback()
The only use of local variable "es1" in in svc_in_callback() and
cport_in_callback() is to get at its hd field. But we already have
that, so we can get rid of that local variable.
Also, rename the "cport" variable "cport_id" in cport_in_callback()
is to match the convention used elsewhere, and make it the proper
u16 type.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Wed, 19 Nov 2014 18:27:13 +0000 (12:27 -0600)]
greybus: explicitly mark cookies as opaque
Use simple macros to mark the conversion of an URB pointer into an
opaque cookie value (and vice-versa). We scramble some bits, but
the main point is to make it explicit where we're returning and
using opaque values.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 19:26:54 +0000 (13:26 -0600)]
greybus: pass gfp_flags for message allocation
The only reason gb_operation_message_init() gets its "outbound"
argument is so we can determine what allocation flags to use.
Just pass the flags in directly instead.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 19:26:53 +0000 (13:26 -0600)]
greybus: stop storing dest_cport_id in message
We can derive the destination CPort id of any (outbound) message
from the connection it's operation is associated with. So we don't
need to store that information in every message.
As a result, we no longer need to record it at message initialization
time.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 19:26:52 +0000 (13:26 -0600)]
greybus: stop storing hd in message
The host device pointer doesn't have to be stored in every message.
It can be derived by following up the chain of pointers back to
the operation's connection.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 19:26:51 +0000 (13:26 -0600)]
greybus: kill the last gbuf remnants
All the code has now been adjusted such that we can do away with the
old gbuf structure.
Three unused references remained in "greybus.h", so those are deleted.
Other than that most of the changes were done by simple global
substitution. The gb_message structure incorporates the fields that
were previously found its embedded gbuf structure. A few names have
been changed in the process:
gbuf->transfer_buffer message->buffer
gbuf->transfer_buffer_size message->buffer_size
gbuf->hcd_data; message->cookie
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 19:26:50 +0000 (13:26 -0600)]
greybus: rework receve handling
Rework gb_connection_operation_recv() to be more oriented toward an
operation message, and to no longer use a struct gbuf local variable.
Rename it to be a little more wieldy.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 19:26:46 +0000 (13:26 -0600)]
greybus: send buffers without gbufs
Change the method that sends messages so that it sends "raw" buffers
rather than gbufs. To do this, we supply the host device and
destination CPort when sending. As with other recent patches,
change the name of the method to reflect that we're no longer
dealing with gbufs.
The interface has changed as well. Now this routine will return a
"cookie" value. The cookie is used to represent the outgoing
request, and is supplied by the caller if necessary to cancel a
previously-sent buffer. We'll store the result in gbuf->hcd_data
for now (which produces the same result as before...).
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 19:26:45 +0000 (13:26 -0600)]
greybus: stash hd as context for all URBs
This changes the context value stashed with each USB URB so that it
is always the host device pointer.
In cport_out_callback() this allows us to get away with *not*
requiring the gbuf for handling completions any more. We are
(currently) ignoring the gbuf status value returned anyway, so
we'll skip setting it altogether.
Greg's comments in cport_out_callback() point out that ignoring
this was misguided, and handling send errors will be put in
place in an upcoming patch.
The context is set to the host device pointer for SVC receive and
CPort receive URBs for consistency--because we can.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 19:26:44 +0000 (13:26 -0600)]
greybus: cancel buffers via magic cookie
Change the interface for canceling in-flight buffers to take a magic
cookie value as argument rather than a gbuf. Right now we pass the
gbuf->hcd_data pointer that's assumed to have been set by the submit
routine. But the next patch will change the submit routine to
return the cookie to be used, and the caller will be responsible for
keeping track of it.
Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Alex Elder [Tue, 18 Nov 2014 19:26:42 +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>
This driver implements the Greybus vibrator protocol, as defined in the
Greybus protocol specification. It interacts to userspace with a single
sysfs file, "timeout", and a separate "class" called "vibrator". That
interface can/should be changed in the future depending on what Android
wants for its HAL, but for now should be good enough to test with.
There are some changes needed to kernel_ver.h to support some
sysfs/driver core changes that happened after the 3.10 kernel was
released to try to make the code simpler. Even with those changes,
there are #ifdefs in the code to do different things depending on the
kernel version to implement the same userspace api.
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.
projects / mirror_ubuntu-zesty-kernel.git / log