msm: driver for rmnet virtual ethernet interface

The MSM7X00A baseband makes up to 3 "virtual ethernet" channels available,
which allow ethernet packets to be exchanged with the cellular network, once
an appropriate data connection is established.

Signed-off-by: Brian Swetland <swetland@google.com>
Signed-off-by: San Mehat <san@android.com>

[ARM] msm_rmnet: HACK: do not count ARP packets

The android network traffic watchdog is tricked into thinking that
data traffic is working at times when it isn't, due to ARP traffic
between the apps and modem processor.  Don't count ARP packets in
link statistics to avoid this problem.

[ARM] msm: rmnet: Add stat tracking for number of radio wakeups occur.

There are two paramaters that appear for all rmnet devices.

rmnet0 for example:
/sys/devices/virtual/net/rmnet0/timeout (RW)
/sys/devices/virtual/net/rmnet0/wakeups (RO)

timeout is configured by userspace for the proper network timeout values
wakeups is the number of radio wakeups that occured.

By default timeout is zero which means the stats are disabled.

MSM_RMNET_DEBUG must be set.

Signed-off-by: Mike Chan <mike@android.com>

[ARM] msm: rmnet: Track wakeups due to xmit/rcv instead of globally.

Signed-off-by: Mike Chan <mike@android.com>

[ARM] msm: rmnet: Different stat timeouts when screen is on/off.

Timeout for modem powerdown can differ when the screen is on/off.
Allow timeout to change via early suspend/resume hooks.

Signed-off-by: Mike Chan <mike@android.com>

[ARM] msm: rmnet: Lock a wakelock for half a second when receiving data.

Signed-off-by: Arve Hjønnevåg <arve@android.com>

[ARM] msm: rmnet: Tracks total awake time when the rmnet is active.

Exports data in /sys/devices/virtual/net/rmnet0/awake_time_ms
in time expressed as ms awake.

Signed-off-by: Mike Chan <mike@android.com>

[ARM] msm: rmnet: Fix compilation issue when MSM_RMNET_DEBUG is not set.

Signed-off-by: Dima Zavin <dima@android.com>

msm_rmnet: fix to build on 2.6.32

Change-Id: Ic6a4903dd12ea83723354d00f639ae2f9375167f

msm_rmnet: ensure packet writes are atomic

Use the smd_write_atomic() function to prevent concurrent
packet writes to the transport from stepping on each other.

Signed-off-by: Brian Swetland <swetland@google.com>