1 Display Controller 2 ------------------ 3 4 (there isn't yet a generic binding in Linux, so this describes what is in 5 U-Boot, and may change based on Linux activity) 6 7 The device node for a display device is as described in the document 8 "Open Firmware Recommended Practice : Universal Serial Bus" with the 9 following modifications and additions : 10 11 Required properties : 12 - compatible : Should be "nvidia,tegra20-dc" 13 14 Required subnode 'rgb' is as follows: 15 16 Required properties (rgb) : 17 - nvidia,panel : phandle of LCD panel information 18 19 20 The panel node describes the panel itself. This has the properties listed in 21 displaymode.txt as well as: 22 23 Required properties (panel) : 24 - nvidia,bits-per-pixel: number of bits per pixel (depth) 25 - nvidia,pwm : pwm to use to set display contrast (see tegra20-pwm.txt) 26 - nvidia,panel-timings: 4 cells containing required timings in ms: 27 * delay before asserting panel_vdd 28 * delay between panel_vdd-rise and data-rise 29 * delay between data-rise and backlight_vdd-rise 30 * delay between backlight_vdd and pwm-rise 31 * delay between pwm-rise and backlight_en-rise 32 33 Optional GPIO properies all have (phandle, GPIO number, flags): 34 - nvidia,backlight-enable-gpios: backlight enable GPIO 35 - nvidia,lvds-shutdown-gpios: LVDS power shutdown GPIO 36 - nvidia,backlight-vdd-gpios: backlight power GPIO 37 - nvidia,panel-vdd-gpios: panel power GPIO 38 39 Example: 40 41 host1x { 42 compatible = "nvidia,tegra20-host1x", "simple-bus"; 43 reg = <0x50000000 0x00024000>; 44 interrupts = <0 65 0x04 /* mpcore syncpt */ 45 0 67 0x04>; /* mpcore general */ 46 47 #address-cells = <1>; 48 #size-cells = <1>; 49 status = "okay"; 50 51 ranges = <0x54000000 0x54000000 0x04000000>; 52 53 dc@54200000 { 54 compatible = "nvidia,tegra20-dc"; 55 reg = <0x54200000 0x00040000>; 56 interrupts = <0 73 0x04>; 57 status = "okay"; 58 59 rgb { 60 status = "okay"; 61 nvidia,panel = <&lcd_panel>; 62 }; 63 }; 64 }; 65 66 lcd_panel: panel { 67 /* Seaboard has 1366x768 */ 68 clock = <70600000>; 69 xres = <1366>; 70 yres = <768>; 71 left-margin = <58>; 72 right-margin = <58>; 73 hsync-len = <58>; 74 lower-margin = <4>; 75 upper-margin = <4>; 76 vsync-len = <4>; 77 hsync-active-high; 78 nvidia,bits-per-pixel = <16>; 79 nvidia,pwm = <&pwm 2 0>; 80 nvidia,backlight-enable-gpios = <&gpio 28 0>; /* PD4 */ 81 nvidia,lvds-shutdown-gpios = <&gpio 10 0>; /* PB2 */ 82 nvidia,backlight-vdd-gpios = <&gpio 176 0>; /* PW0 */ 83 nvidia,panel-vdd-gpios = <&gpio 22 0>; /* PC6 */ 84 nvidia,panel-timings = <400 4 203 17 15>; 85 }; 86
