Re: [RFC PATCH V3] ARM: dts: sun6i: Add dts file for MSI Primo81 tablet

Hi,

On Tue, Jun 16, 2015 at 09:11:08PM +0200, Karsten Merker wrote:

On Tue, Jun 16, 2015 at 11:40:27AM +0200, Maxime Ripard wrote:

quoted

What I meant in my previous review was to use the syntax

&uart0 {
       some-property;
};
  
Instead of duplicating the tree structure like you're doing
here. We've converted all the DT to that, so you can look around and
see how it's done in other boards (note that the nodes should be
sorted by alphabetical order).

Ah, sorry, I had misunderstood your original email in this regard.
Following is a reworked version of the patch.

Changelog:

Version 1
=========
- Original patch by Siarhei Siamashka

Version 2
=========
- Use symbolic instead of numeric pinctrl values.

- Change the include syntax from /include/ to #include to make
  the dts build with current kernels.

Version 3
=========
- Use labels for nodes with modifications in relation to the dtsi
  instead of replicating the tree structure.

- Remove the FSF address from the license header as done in
  http://lists.infradead.org/pipermail/linux-arm-kernel/2015-May/340437.html
  for the other dts files to remove a checkpatch warning.

- Add msi to the vendor prefix list.

- Remove earlyprintk from the default kernel commandline.

- Replace the console kernel commandline parameter by a
  /chosen/stdout-path node and add an alias serial0 -> uart0.

Next time, pleas try to keep the changelog with your patch, it's much
easier to read.

And please make the vendor prefix change a different patch.

I have tagged this patch RFC as I am unsure what to do with the
/chosen/stdout-path node. For now, I have set Siarhei's original
choice (first serial port), but I am unsure whether this is the
right thing to do as the Primo81 does by default not have a
user-accessible serial port.  The only way to get a serial
console is to either break the case open and find some test
points that carry the RX/TX lines (which with the Primo81 case
poses a high risk of breaking the display glass), or to use an SD
card breakout board and change the pinmuxing for the SD card pins
to the "serial" function.  The latter would not work without
modifying the dts, so the SD-breakout case doesn't really count
for setting the default stdout-path in the general use case.

Having that as a comment on top of whatever uart you've been using
would be great, so that people know where to look at on their device
to find it.

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com