Currently the i2400m driver was resetting by just calling
i2400m->bus_reset(). However, this was missing stopping the TX queue
and downing the carrier. This was causing, for the corner case of the
driver reseting a device that refuses to go out of idle mode, that a
few packets would be queued and more than one reset would go through,
making the recovery a wee bit messy.

To avoid introducing the same cleanup in all the bus-specific driver,
introduced a i2400m_reset() function that takes care of house cleaning
and then calling the bus-level reset implementation.

The bulk of the changes in all files are just to rename the call from
i2400m->bus_reset() to i2400m_reset().
Signed-off-by: NInaky Perez-Gonzalez <inaky@linux.intel.com>

The i2400m might start sending reports to the driver before it is done
setting up all the infrastructure needed for handling them.

Currently we were just dropping them when the driver wasn't ready and
that is bad in certain situations, as the sync between the driver's
idea of the device's state and the device's state dissapears.

This changes that by implementing a queue for handling
reports. Incoming reports are appended to it and a workstruct is woken
to process the list of queued reports.

When the device is not yet ready to handle them, the workstruct is not
woken, but at soon as the device becomes ready again, the queue is
processed.

As a consequence of this, i2400m_queue_work() is no longer used, and
thus removed.
Signed-off-by: NInaky Perez-Gonzalez <inaky@linux.intel.com>

The i2400m driver uses two different bits to distinguish how much the
driver is up. i2400m->ready is used to denote that the infrastructure
to communicate with the device is up and running. i2400m->updown is
used to indicate if 'ready' and the device is up and running, ready to
take control and data traffic.

However, all this was pretty dirty and not clear, with many open spots
where race conditions were present.

This commit cleans up the situation by:

 - documenting the usage of both bits

 - setting them only in specific, well controlled places
   (i2400m_dev_start, i2400m_dev_stop)

 - ensuring the i2400m workqueue can't get in the middle of the
   setting by flushing it when i2400m->ready is set to zero. This
   allows the report hook not having to check again for the bit to be
   set [rx.c:i2400m_report_hook_work()].

 - using i2400m->updown to determine if the device is up and running
   instead of the wimax state in i2400m_dev_reset_handle().

 - not loosing missed messages sent by the hardware before
   i2400m->ready is set. In rx.c, whatever the device sends can be
   sent to user space over the message pipes as soon as the wimax
   device is registered, so don't wait for i2400m->ready to be set.
Signed-off-by: NInaky Perez-Gonzalez <inaky@linux.intel.com>

This modifies the bootrom initialization code of the i2400m driver so
it can more easily support upcoming hardware.

Currently, the code detects two types of barkers (magic numbers) sent
by the device to indicate the types of firmware it would take (signed
vs non-signed).

This schema is extended so that multiple reboot barkers are
recognized; upcoming hw will expose more types barkers which will have
to match a header in the firmware image before we can load it.

For that, a barker database is introduced; the first time the device
sends a barker, it is matched in the database. That gives the driver
the information needed to decide how to upload the firmware and which
types of firmware to use. The database can be populated from module
parameters.

The execution flow is not altered; a new function
(i2400m_is_boot_barker) is introduced to determine in the RX path if
the device has sent a boot barker. This function is becoming heavier,
so it is put away from the hot reception path [this is why there is
some reorganization in sdio-rx.c:i2400ms_rx and
usb-notifc.c:i2400mu_notification_grok()].

The documentation on the process has also been updated.

All these modifications are heavily based on previous work by Dirk
Brandewie <dirk.brandewie@intel.com>.
Signed-off-by: NInaky Perez-Gonzalez <inaky@linux.intel.com>

The constant is being use as an alignment factor, not as a padding
factor; made reading/reviewing the code quite confusing.
Signed-off-by: NInaky Perez-Gonzalez <inaky@linux.intel.com>

Functions i2400m_report_tlv*() are only called from
i2400m_report_hook(), called in a workqueue by
i2400m_report_hook_work(). The scheduler checks for device readiness
before scheduling.

Added an extra check for readiness in i2400m_report_hook_work(), which
makes all the checks down the line redundant.

Obviously the device state could change in the middle, but error
handling would take care of that.
Signed-off-by: NInaky Perez-Gonzalez <inaky@linux.intel.com>

When commands are sent from user space, trace both the command sent
and the answer received over the "echo" pipe instead of over the
"trace" pipe when command tracing is enabled. As well, when the device
sends a reports/indications, send it over the "echo" pipe.

The "trace" pipe is used by the device to send firmware traces;
gets confusing. Another named pipe makes it easier to split debug
information.
Signed-off-by: NInaky Perez-Gonzalez <inaky@linux.intel.com>

When the i2400m receives data and the device indicates there has to be
reordering, we keep an sliding window implementation to sort the
packets before sending them to the network stack.

One of the "operations" that the device indicates is "queue a packet
and update the window start". When the queue is empty, this is
equivalent to "deliver the packet and update the window start".

That case was optimized in i2400m_roq_queue_update_ws() so that we
would not pointlessly queue and dequeue a packet. However, when the
optimization was active, it wasn't updating the window start. That
caused the reorder management code to get confused later on with what
seemed to be wrong reorder requests from the device.

Thus the fix implemented is to do the right thing and update the
window start in both cases, when the queue is empty (and the
optimization is done) and when not.
Signed-off-by: NInaky Perez-Gonzalez <inaky@linux.intel.com>

Allow the device to give the driver RX data with reorder information.

When that is done, the device will indicate the driver if a packet has
to be held in a (sorted) queue. It will also tell the driver when held
packets have to be released to the OS.

This is done to improve the WiMAX-protocol level retransmission
support when missing frames are detected.

The code docs provide details about the implementation.

In general, this just hooks into the RX path in rx.c; if a packet with
the reorder bit in the RX header is detected, the reorder information
in the header is extracted and one of the four main reorder operations
are executed. In one case (queue) no packet will be delivered to the
networking stack, just queued, whereas in the others (reset, update_ws
and queue_update_ws), queued packet might be delivered depending on
the window start for the specific queue.

The modifications to files other than rx.c are:

- control.c: during device initialization, enable reordering support
  if the rx_reorder_disabled module parameter is not enabled

- driver.c: expose a rx_reorder_disable module parameter and call
  i2400m_rx_setup/release() to initialize/shutdown RX reorder
  support.

- i2400m.h: introduce members in 'struct i2400m' needed for
  implementing reorder support.

- linux/i2400m.h: introduce TLVs, commands and constant definitions
  related to RX reorder

Last but not least, the rx reorder code includes an small circular log
where the last N reorder operations are recorded to be displayed in
case of inconsistency. Otherwise diagnosing issues would be almost
impossible.
Signed-off-by: NInaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Newer i2400m firmwares (>= v1.4) extend the data RX protocol so that
each packet has a 16 byte header. This header is mainly used to
implement host reordeing (which is addressed in later commits).

However, this header also allows us to overwrite it (once data has
been extracted) with an Ethernet header and deliver to the networking
stack without having to reallocate the skb (as it happened in fw <=
v1.3) to make room for it.

- control.c: indicate the device [dev_initialize()] that the driver
  wants to use the extended data RX protocol. Also involves adding the
  definition of the needed data types in include/linux/wimax/i2400m.h.

- rx.c: handle the new payload type for the extended RX data
  protocol. Prepares the skb for delivery to
  netdev.c:i2400m_net_erx().

- netdev.c: Introduce i2400m_net_erx() that adds the fake ethernet
  address to a prepared skb and delivers it to the networking
  stack.

- cleanup: in most instances in rx.c, the variable 'single' was
  renamed to 'single_last' for it better conveys its meaning.
Signed-off-by: NInaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove some pointless conditionals before kfree_skb().
Signed-off-by: NWei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Handling of TX/RX data to/from the i2400m device (IP packets, control
and diagnostics). On RX, this parses the received read transaction
from the device, breaks it in chunks and passes it to the
corresponding subsystems (network and control).

Transmission to the device is done through a software FIFO, as
data/control frames can be coalesced (while the device is reading the
previous tx transaction, others accumulate). A FIFO is used because at
the end it is resource-cheaper that scatter/gather over USB. As well,
most traffic is going to be download (vs upload).
Signed-off-by: NInaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>