mm: writeback: every 500ms the writeback daemon kicks in and flushes the dirty pages into disk. Thats not very pleasant for performance and *maybe* battery. This patch disables the writeback function while the screen is on, and enables it back when the screen is off to flush all the dirty pages. In my real world usage testing I notice a slight bump in smoothness and performance while using the device.

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>

Conflicts:
	mm/page-writeback.c

+ need testing ...

boype: writeback value changed to my previous setting.
Signed-off-by: artas182x <artas182x@gmail.com>
omap_hsi: small workaround for tx 5 rx 2 errors * additional cleanup of logspam * this doesn't fix the shitty low battery modem errors

Signed-off-by: artas182x <artas182x@gmail.com>
OMAP4: PM: fix overconsumption on OFF mode

The wrong value of CM_L3INIT_CLKSTCTRL.CLKTRCTRL = 2 (SW_WKUP)
has been stored in SAR during omap4_sar_save() execution and
causes power over consumption on OFF mode due to C2C operation.
It happens because the L3INIT CD need to be enabled during
omap4_sar_save() execution for proper USBHOST module context storing.

Problematic use case:
1) OMAP goes to sleep,
2) modem wakeup the C2C, the EMIF but the MPU is still sleeping
(as expected)
3) Modem release all his constraints, C2C is turned to OFF.
4) but OMAP never reach again OFF while we don't wakeup the CPU
(by a keypress for example), sys_clk is already ON and voltages
are not equal to 0. (OPP 50 for CORE_3 and retention voltages
for both VCORE1 and VCORE2).

As WA overwrite CM_L3INIT_CLKSTCTRL.CLKTRCTRL = 0x1 (SW_SLEEP).

Change-Id: I2e453c07f61bab28a7213dd66044fd41a021961b
Signed-off-by: Arthur Cassegrain <a-cassegrain@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>

Patch Set 1
Signed-off-by: artas182x <artas182x@gmail.com>
This reverts commit be733aa499ab7081f7470af3da3d60906c0f407a.