From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hans de Goede Date: Fri, 14 Nov 2014 09:50:42 +0000 Subject: Re: [PATCH] dt-bindings: simplefb: Document naming scheme for pre-populated simplefb nodes Message-Id: <5465D072.1000407@redhat.com> List-Id: References: <1415955751-6316-1-git-send-email-hdegoede@redhat.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-arm-kernel@lists.infradead.org Hi, On 11/14/2014 10:12 AM, Grant Likely wrote: > On Fri, Nov 14, 2014 at 9:02 AM, Hans de Goede wrote: >> Since we advice to use pre-populated simeplfb nodes in dt files, where the >> firmware then only needs to fill in the mode info + address and enable it, >> we should also specify how these pre-populated nodes should be named so >> that the firmware can find and enable the right one. >> >> Signed-off-by: Hans de Goede >> --- >> Documentation/devicetree/bindings/video/simple-framebuffer.txt | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/video/simple-framebuffer.txt b/Documentation/devicetree/bindings/video/simple-framebuffer.txt >> index c548f33..01dc948 100644 >> --- a/Documentation/devicetree/bindings/video/simple-framebuffer.txt >> +++ b/Documentation/devicetree/bindings/video/simple-framebuffer.txt >> @@ -29,6 +29,13 @@ enable them. This way if e.g. later on support for more display clocks get >> added, the simplefb nodes will already contain this info and the firmware >> does not need to be updated. >> >> +If pre-filled framebuffer nodes are used, they should be named >> +"framebuffer#-", e.g. "framebuffer0-hdmi". The output should be >> +included in the name since different outputs typically require different >> +clocks and the clocks are part of the pre-populated nodes. The firmware must >> +rename the nodes to the standard "framebuffer@
" using the runtime >> +chosen address when enabling the nodes. > > - should be optional, an only used when there are multiple options. Right, notice the "should be named", I would rather leave it at that then complicate the wording by adding something about only use -output when there are multiple options. > Something we've not talked about is how to handle a framebuffer that > has been set up with mirrored displays. Does that case matter? It is bound to happen sooner or later I guess, but it is still just a single framebuffer, so from the simplefb kernel driver pov it does not matter, it really is just another variant on the - theme where there happen to be 2 outputs active at the same time. Regards, Hans > > g. >