| Message ID | 20230206184744.2.I13814cefc5ab3e0a39ebd09f052e3fd25d4e8f1d@changeid (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | 4261cea17a2f5e0ec78eb3ceebb68dddb918aee9 |
| Headers | show |
| Series | arm: qcom: Fix touchscreen voltage for sc7280-herobrine boards | expand |
On Mon, Feb 06, 2023 at 06:48:11PM -0800, Douglas Anderson wrote: > The "pp3300_left_in_mlb" rail on herobrine eventually connects up to > "vreg_edp_3p3" on the qcard. On several herobrine designs this rail > has been measured to need more than 1ms to turn on. > > While technically a herobrine derivative (defined as anyone including > the "herobrine.dtsi") could change the board to make the rail rise > faster or slower, the fact that two boards (evoker and villager) both > measured it as taking more than 1ms implies that it's probably going > to be the norm. Thus, let's add a "regulator-enable-ramp-delay" > straight into the herobrine.dtsi to handle this. If a particular > derivative board needs a faster or slower one then they can override > it, though that feels unlikely. > > While we measured something a bit over 1ms, we'll choose 3ms to give > us a tiny bit of margin. This isn't a rail that turns off and on all > the time anyway and 3ms is nothing compared to the total amount of > time to power on a panel. > > Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
diff --git a/arch/arm64/boot/dts/qcom/sc7280-herobrine.dtsi b/arch/arm64/boot/dts/qcom/sc7280-herobrine.dtsi index 27f479ff9d80..ded36b5d28c7 100644 --- a/arch/arm64/boot/dts/qcom/sc7280-herobrine.dtsi +++ b/arch/arm64/boot/dts/qcom/sc7280-herobrine.dtsi @@ -108,6 +108,8 @@ pp3300_left_in_mlb: pp3300-left-in-mlb-regulator { pinctrl-names = "default"; pinctrl-0 = <&en_pp3300_dx_edp>; + regulator-enable-ramp-delay = <3000>; + vin-supply = <&pp3300_z1>; };
The "pp3300_left_in_mlb" rail on herobrine eventually connects up to "vreg_edp_3p3" on the qcard. On several herobrine designs this rail has been measured to need more than 1ms to turn on. While technically a herobrine derivative (defined as anyone including the "herobrine.dtsi") could change the board to make the rail rise faster or slower, the fact that two boards (evoker and villager) both measured it as taking more than 1ms implies that it's probably going to be the norm. Thus, let's add a "regulator-enable-ramp-delay" straight into the herobrine.dtsi to handle this. If a particular derivative board needs a faster or slower one then they can override it, though that feels unlikely. While we measured something a bit over 1ms, we'll choose 3ms to give us a tiny bit of margin. This isn't a rail that turns off and on all the time anyway and 3ms is nothing compared to the total amount of time to power on a panel. Signed-off-by: Douglas Anderson <dianders@chromium.org> --- arch/arm64/boot/dts/qcom/sc7280-herobrine.dtsi | 2 ++ 1 file changed, 2 insertions(+)