[Outreachy kernel] [PATCH] staging: fbtft: Replace udelay with preferred usleep_range

[John B. Wyatt IV]

On Mon, 2020-03-30 at 19:40 +0200, Stefano Brivio wrote:
> On Sun, 29 Mar 2020 12:37:18 +0200 (CEST)
> Julia Lawall <julia.lawall at inria.fr> wrote:
> 
> > On Sun, 29 Mar 2020, Soumyajit Deb wrote:
> > 
> > > I had the same doubt the other day about the replacement of
> > > udelay() with
> > > usleep_range(). The corresponding range for the single argument
> > > value of
> > > udelay() is quite confusing as I couldn't decide the range. But
> > > as much as I
> > > noticed checkpatch.pl gives warning for replacing udelay() with
> > > usleep_range() by checking the argument value of udelay(). In the
> > > documentation, it is written udelay() should be used for a sleep
> > > time of at
> > > most 10 microseconds but between 10 microseconds and 20
> > > milliseconds,
> > > usleep_range() should be used. 
> > > I think the range is code specific and will depend on what range
> > > is
> > > acceptable and doesn't break the code.
> > >  Please correct me if I am wrong.  
> > 
> > The range depends on the associated hardware.
> 
> John, by the way, here you could have checked the datasheet of this
> LCD
> controller. It's a pair of those:
> 	https://www.sparkfun.com/datasheets/LCD/ks0108b.pdf
> 

No I have not. This datasheet is a little over my head honestly.

What would you recommend to get familiar with datasheets like this?