arm64: tegra: Add backlight node on Smaug

The Google Pixel C has a TI LP8557 backlight controller, so add a
DT node for it.

Signed-off-by: Diogo Ivo <diogo.ivo@tecnico.ulisboa.pt>
Signed-off-by: Thierry Reding <treding@nvidia.com>

diff --git a/arch/arm64/boot/dts/nvidia/tegra210-smaug.dts b/arch/arm64/boot/dts/nvidia/tegra210-smaug.dts
index 9acf33aae902dcd650747dd8a4ef0bb0cf0845bf..9c8ffbf8ef65486857bde097534e8c728c241d50 100644 (file)
--- a/arch/arm64/boot/dts/nvidia/tegra210-smaug.dts
+++ b/arch/arm64/boot/dts/nvidia/tegra210-smaug.dts
@@ -1651,6 +1651,37 @@
                        status = "okay";
                };
 
+               backlight: backlight@2c {
+                       compatible = "ti,lp8557";
+                       reg = <0x2c>;
+                       power-supply = <&pplcd_vdd>;
+                       enable-supply = <&pp1800_lcdio>;
+                       bl-name = "lp8557-backlight";
+                       dev-ctrl = /bits/ 8 <0x01>;
+                       init-brt = /bits/ 8 <0x80>;
+
+                       /* Full scale current, 20mA */
+                       rom-11h {
+                               rom-addr = /bits/ 8 <0x11>;
+                               rom-val = /bits/ 8 <0x05>;
+                       };
+                       /* Frequency = 4.9kHz, magic undocumented val */
+                       rom-12h {
+                               rom-addr = /bits/ 8 <0x12>;
+                               rom-val = /bits/ 8 <0x29>;
+                       };
+                       /* Boost freq = 1MHz, BComp option = 1 */
+                       rom-13h {
+                               rom-addr = /bits/ 8 <0x13>;
+                               rom-val = /bits/ 8 <0x03>;
+                       };
+                       /* 4V OV, 6 output LED string enabled */
+                       rom-14h {
+                               rom-addr = /bits/ 8 <0x14>;
+                               rom-val = /bits/ 8 <0xbf>;
+                       };
+               };
+
                audio-codec@2d {
                        compatible = "realtek,rt5677";
                        reg = <0x2d>;