- Oct 23, 2021
If anyone is interested, here are the side-by-side comparison photos of the same SM-A127F/DSN, one made in India and another made in Vietnam. The one made in Vietnam clearly has a different brand of screen and is susceptible to the "no touchscreen response after wake-up" problem in Lineage OS and other non-stock GSI's. The screen used by the manufacturers in India clearly has better viewing angles, more brightness with the same settings, more pleasant white color balance and, most important of all, it has no problem with the touch screen. I don't know how this problem is solved in the stock firmware but clearly Samsung was aware of it and put something extra into the wake-up code, may be some special GPIO command to take the screen controller from the deep sleep mode. The lshal list of both phones, at least the one reported by LineageOS, is completely identical.