mdss: display: add spin_lock to mdss_disable_irq_nosync()

Add spin_lock to mdss_lock inside mdss_disable_irq_nosync
to avoid race condition which can cause mdss_irq to be disabled
while irq_mask bits are still set.

CRs-Fixed: 624806
Change-Id: I44074a057dff49dfc7a4d2829f3c4e599dca4a69
Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
msm: mdss: Fix BWC width alignment

BWC src width is segmented into 16 aligned RAUs. The segmentation
into 16 RAUs needs to be rounded up for corner cases.

Change-Id: Idbf675d7adfb45cb28e6c456dd4fd7c7f41ea280
Signed-off-by: Sree Sesha Aravind Vadrevu <svadrevu@codeaurora.org>
msm: mdss: Notify userspace of idle screen case

Expose two new sysfs nodes - idle_time and idle_notify - that
are used to notify userspace whenever the display is idle with
no screen updates. The idle_time node needs to be configured
with the duration in milliseconds to detect no screen updates.
The userspace app can poll on the idle_notify node to get
notifications of the idle state.

Change-Id: I7435a084ad2c928d952c5d106ff9ef92aaa385b9
Signed-off-by: Aravind Venkateswaran <aravindh@codeaurora.org>
Signed-off-by: Neti Ravi Kumar <ravineti@codeaurora.org>
CRs-Fixed: 637403

Conflicts:
	drivers/video/msm/mdss/mdss_fb.c