From 1675d1884aab50d051dc99e4eab709a75ce11dff Mon Sep 17 00:00:00 2001 From: Ingrid Gallardo Date: Thu, 22 Sep 2016 21:20:08 -0700 Subject: msm: mdss: add mdp guard window property For some panels, the mdp kickoff transaction must be controlled and only triggered when the scanline is within certain region. This change adds the support to control the scanline where the kickoff can be triggered through panel properties and if the scanline is not within this region, then driver will wait for an extra delay that is also configurable through a panel property. Change-Id: I06bc6b03f77109adfed428b876915f59d3b5bbfd Signed-off-by: Ingrid Gallardo --- .../devicetree/bindings/fb/mdss-dsi-panel.txt | 31 ++++++++++++++++++++++ 1 file changed, 31 insertions(+) (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/fb/mdss-dsi-panel.txt b/Documentation/devicetree/bindings/fb/mdss-dsi-panel.txt index 90abf0305319..68b8f09238e0 100644 --- a/Documentation/devicetree/bindings/fb/mdss-dsi-panel.txt +++ b/Documentation/devicetree/bindings/fb/mdss-dsi-panel.txt @@ -249,6 +249,35 @@ Optional properties: 60 = 60 frames per second (default) - qcom,mdss-dsi-panel-clockrate: A 64 bit value specifies the panel clock speed in Hz. 0 = default value. +- qcom,mdss-mdp-kickoff-threshold: This property can be used to define a region + (in terms of scanlines) where the +hardware is allowed + to trigger a data transfer from MDP to DSI. + If this property is used, the region must be defined setting + two values, the low and the high thresholds: + + Where following condition must be met: + low_threshold < high_threshold + These values will be used by the driver in such way that if + the Driver receives a request to kickoff a transfer (MDP to DSI), + the transfer will be triggered only if the following condition + is satisfied: + low_threshold < scanline < high_threshold + If the condition is not met, then the driver will delay the + transfer by the time defined in the following property: + "qcom,mdss-mdp-kickoff-delay". + So in order to use this property, the delay property must + be defined as well and greater than 0. +- qcom,mdss-mdp-kickoff-delay: This property defines the delay in microseconds that + the driver will delay before triggering an MDP transfer if the + thresholds defined by the following property are not met: + "qcom,mdss-mdp-kickoff-threshold". + So in order to use this property, the threshold property must + be defined as well. Note that this delay cannot be zero + and also should not be greater than +the fps window. + i.e. For 60fps value should not exceed +16666 uS. - qcom,mdss-mdp-transfer-time-us: Specifies the dsi transfer time for command mode panels in microseconds. Driver uses this number to adjust the clock rate according to the expected transfer time. @@ -568,6 +597,8 @@ Example: qcom,mdss-dsi-dma-trigger = <0>; qcom,mdss-dsi-panel-framerate = <60>; qcom,mdss-dsi-panel-clockrate = <424000000>; + qcom,mdss-mdp-kickoff-threshold = <11 2430>; + qcom,mdss-mdp-kickoff-delay = <1000>; qcom,mdss-mdp-transfer-time-us = <12500>; qcom,mdss-dsi-panel-timings = [7d 25 1d 00 37 33 22 27 1e 03 04 00]; -- cgit v1.2.3