On 11/21/2015 1:29 AM, Rob Herring wrote: > +Stephen > > On Wed, Nov 18, 2015 at 9:24 AM, Archit Taneja <architt at codeaurora.org> > wrote: >> Hi Rob, >> >> On 11/18/2015 6:48 PM, Rob Herring wrote: >>> >>> +dt list >>> >>> On Wed, Nov 18, 2015 at 4:55 AM, Archit Taneja <architt at codeaurora.org> >>> wrote: >>>> >>>> Add additional property info needed for DSIv2 DT. >>> >>> >>> Please use get_maintainers.pl. >> >> >> Sorry about that, missed out doing that posting this time. >> >>> >>>> Signed-off-by: Archit Taneja <architt at codeaurora.org> >>>> --- >>>> Documentation/devicetree/bindings/display/msm/dsi.txt | 10 +++++++++- >>>> 1 file changed, 9 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/Documentation/devicetree/bindings/display/msm/dsi.txt >>>> b/Documentation/devicetree/bindings/display/msm/dsi.txt >>>> index f344b9e..ca65a34 100644 >>>> --- a/Documentation/devicetree/bindings/display/msm/dsi.txt >>>> +++ b/Documentation/devicetree/bindings/display/msm/dsi.txt >>>> @@ -13,18 +13,25 @@ Required properties: >>>> - power-domains: Should be <&mmcc MDSS_GDSC>. >>>> - clocks: device clocks >>>> See Documentation/devicetree/bindings/clocks/clock-bindings.txt for >>>> details. >>>> -- clock-names: the following clocks are required: >>>> +- clock-names: these vary based on the DSI version. For DSI6G: >>>> * "bus_clk" >>>> * "byte_clk" >>>> + * "byte_clk_src >>> >>> >>> This sounds like the parent of byte_clk. Is that really a clock within >>> the block? >> >> >> byte_clk_src isn't in the block, but byte_clk_src's parent is one of >> the PLLs in this block. We take this clock so that we can re-parent >> it to an appropriate PLL. The decision of what PLL to choose needs to >> be done by the DSI block's driver. > > Seems like abuse to me. The list of clocks should match what are > inputs to the block, not what the driver happens to need. Without a > full understanding of the clock tree here, I don't have a suggestion. > Maybe Stephen does.
We don't need specify byte_clk_src (and other xyz_clk_src clocks) via DT. There is a static link set up between byte_clk and byte_clk_src by our clock driver that never changes. We can retrieve it in the driver itself using clk_get_parent(byte_clk). This way we stick to only input clocks. Stephen, does that sound okay? > >>>> * "core_clk" >>>> * "core_mmss_clk" >>>> * "iface_clk" >>>> * "mdp_core_clk" >>>> * "pixel_clk" >>>> + * "pixel_clk_src" >>>> + For DSIv2, we need a few more: >>> >>> >>> What is the overall order of clocks? As listed? >> >> >> Order in which the driver does clk_get? It uses the clock >> name to get each one individually, so the order doesn't matter >> as such. > > The order in DT. You may use the names, but the order should still be > specified. Okay. I'll cross check and make sure the order is as in our DT files. Archit > > Rob > -- > To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in > the body of a message to majordomo at vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
