Public bug reported:

== Impact ==
The i2c-designware stops working after S4 thus I2C devices connected to it 
can't be accessed.
[  272.628526] PM: Timekeeping suspended for 115.313 seconds
[  272.633110] ACPI: Waking up from system sleep state S4
[  272.655524] PM: noirq restore of devices complete after 19.377 msecs
[  272.775692] i2c_designware 80860F41:00: Unknown Synopsys component type: 
0xffffffff
[  272.876322] PM: early restore of devices complete after 219.859 msecs
...
[  273.060760] i2c_designware 80860F41:00: timeout waiting for bus ready
[  274.214314] i2c_designware 80860F41:00: timeout in disabling adapter

== Fix ==
This happens after these two commits:
* 36c27d206b21 - PM: i2c-designware-platdrv: Optimize power management 
(2018-12-07 16:21:11 +0800)
* 489cd2fafa2d - PM: i2c-designware-platdrv: Use DPM_FLAG_SMART_PREPARE 
(2018-12-07 16:21:11 +0800)
Until there's a proper fix for them, both of them need to be reverted in order 
to make S4 works again.

== Test Case ==
Boot with the kernel, S4, and then wake the system up.

== Risk of Regression ==
Risk should be low since we're removing new features.

** Affects: linux-oem (Ubuntu)
     Importance: Undecided
     Assignee: Jesse Sung (wenchien)
         Status: In Progress

** Summary changed:

- i2c-dw stops working after S4 on CHT platforms
+ i2c-designware stops working after S4 on CHT platforms

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https://bugs.launchpad.net/bugs/1810223

Title:
  i2c-designware stops working after S4 on CHT platforms

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