Re: [PATCH 6/6] drm/msm/dsi: Parse DSI lanes via DT
From: Rob Herring <robh@kernel.org>
Date: 2016-02-22 02:53:45
Also in:
dri-devel, linux-arm-msm
On Mon, Feb 15, 2016 at 06:30:59PM +0530, Archit Taneja wrote:
quoted hunk ↗ jump to hunk
The DSI driver is currently unaware of how the DSI clock and data pins are mapped to the logical lanes provided by the DSI controller. Use the generic 'lanes' DT binding provided for DSI lanes (used for DSI in bindings/display/ti/ti,omap4-dss.txt) to get the desired mapping. The MSM DSI controller is restricted in terms of what all mappings it can support. The lane polarity is fixed for all the lanes, the clock lanes are fixed, and the data lanes can be swapped among each other only for a few combinations. Apply these restrictions when we parse the DT data. Cc: devicetree@vger.kernel.org Cc: Rob Herring <robh@kernel.org> Cc: Tomi Valkeinen <redacted> Signed-off-by: Archit Taneja <redacted> --- .../devicetree/bindings/display/msm/dsi.txt | 26 +++- drivers/gpu/drm/msm/dsi/dsi_host.c | 146 ++++++++++++++++++--- 2 files changed, 149 insertions(+), 23 deletions(-)diff --git a/Documentation/devicetree/bindings/display/msm/dsi.txt b/Documentation/devicetree/bindings/display/msm/dsi.txt index e7423be..f0d8b6f 100644 --- a/Documentation/devicetree/bindings/display/msm/dsi.txt +++ b/Documentation/devicetree/bindings/display/msm/dsi.txt@@ -44,9 +44,28 @@ Optional properties: - pinctrl-names: the pin control state names; should contain "default" - pinctrl-0: the default pinctrl state (active) - pinctrl-n: the "sleep" pinctrl state -- port: DSI controller output port. This contains one endpoint subnode, with its - remote-endpoint set to the phandle of the connected panel's endpoint. - See Documentation/devicetree/bindings/graph.txt for device graph info. +- port: DSI controller output port, containing one endpoint subnode. + + DSI Endpoint properties: + - remote-endpoint: set to phandle of the connected panel's endpoint. + See Documentation/devicetree/bindings/graph.txt for device graph info. + - lanes: list of pin numbers for the DSI lanes: CLKp, CLKn, DATA0p, DATA0n, + DATA1p, DATA1n, ... + This provides a physical to logical mapping of the DSI lanes. The CLKp and + CLKn pins have to be mapped to pins 0 and 1. For data lanes, there are only
Then why describe the clk pins?
+ a limited number of physical to logical mappings possible: + + "0123": Logic 0->Phys 0; Logic 1->Phys 1; Logic 2->Phys 2; Logic 3->Phys 3; + "3012": Logic 3->Phys 0; Logic 0->Phys 1; Logic 1->Phys 2; Logic 2->Phys 3; + "2301": Logic 2->Phys 0; Logic 3->Phys 1; Logic 0->Phys 2; Logic 1->Phys 3; + "1230": Logic 1->Phys 0; Logic 2->Phys 1; Logic 3->Phys 2; Logic 0->Phys 3; + "0321": Logic 0->Phys 0; Logic 3->Phys 1; Logic 2->Phys 2; Logic 1->Phys 3; + "1032": Logic 1->Phys 0; Logic 0->Phys 1; Logic 3->Phys 2; Logic 2->Phys 3; + "2103": Logic 2->Phys 0; Logic 1->Phys 1; Logic 0->Phys 2; Logic 3->Phys 3; + "3210": Logic 3->Phys 0; Logic 2->Phys 1; Logic 1->Phys 2; Logic 0->Phys 3; + + Here, a "3012" mapping will be represented by: + lanes = <0 1 8 9 2 3 4 5 6 7>;
I'm lost here. What does 8 mean for example. The index represents? Rob _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel