name : display_timing.h /* SPDX-License-Identifier: GPL-2.0-only */ /* * Copyright 2012 Steffen Trumtrar <s.trumtrar@pengutronix.de> * * description of display timings */ #ifndef __LINUX_DISPLAY_TIMING_H #define __LINUX_DISPLAY_TIMING_H #include <linux/bitops.h> #include <linux/types.h> enum display_flags { DISPLAY_FLAGS_HSYNC_LOW = BIT(0), DISPLAY_FLAGS_HSYNC_HIGH = BIT(1), DISPLAY_FLAGS_VSYNC_LOW = BIT(2), DISPLAY_FLAGS_VSYNC_HIGH = BIT(3), /* data enable flag */ DISPLAY_FLAGS_DE_LOW = BIT(4), DISPLAY_FLAGS_DE_HIGH = BIT(5), /* drive data on pos. edge */ DISPLAY_FLAGS_PIXDATA_POSEDGE = BIT(6), /* drive data on neg. edge */ DISPLAY_FLAGS_PIXDATA_NEGEDGE = BIT(7), DISPLAY_FLAGS_INTERLACED = BIT(8), DISPLAY_FLAGS_DOUBLESCAN = BIT(9), DISPLAY_FLAGS_DOUBLECLK = BIT(10), /* drive sync on pos. edge */ DISPLAY_FLAGS_SYNC_POSEDGE = BIT(11), /* drive sync on neg. edge */ DISPLAY_FLAGS_SYNC_NEGEDGE = BIT(12), }; /* * A single signal can be specified via a range of minimal and maximal values * with a typical value, that lies somewhere inbetween. */ struct timing_entry { u32 min; u32 typ; u32 max; }; /* * Single "mode" entry. This describes one set of signal timings a display can * have in one setting. This struct can later be converted to struct videomode * (see include/video/videomode.h). As each timing_entry can be defined as a * range, one struct display_timing may become multiple struct videomodes. * * Example: hsync active high, vsync active low * * Active Video * Video ______________________XXXXXXXXXXXXXXXXXXXXXX_____________________ * |<- sync ->|<- back ->|<----- active ----->|<- front ->|<- sync.. * | | porch | | porch | * * HSync _|¯¯¯¯¯¯¯¯¯¯|___________________________________________|¯¯¯¯¯¯¯¯¯ * * VSync ¯|__________|¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|_________ */ struct display_timing { struct timing_entry pixelclock; struct timing_entry hactive; /* hor. active video */ struct timing_entry hfront_porch; /* hor. front porch */ struct timing_entry hback_porch; /* hor. back porch */ struct timing_entry hsync_len; /* hor. sync len */ struct timing_entry vactive; /* ver. active video */ struct timing_entry vfront_porch; /* ver. front porch */ struct timing_entry vback_porch; /* ver. back porch */ struct timing_entry vsync_len; /* ver. sync len */ enum display_flags flags; /* display flags */ }; /* * This describes all timing settings a display provides. * The native_mode is the default setting for this display. * Drivers that can handle multiple videomodes should work with this struct and * convert each entry to the desired end result. */ struct display_timings { unsigned int num_timings; unsigned int native_mode; struct display_timing **timings; }; /* get one entry from struct display_timings */ static inline struct display_timing *display_timings_get(const struct display_timings *disp, unsigned int index) { if (disp->num_timings > index) return disp->timings[index]; else return NULL; } void display_timings_release(struct display_timings *disp); #endif