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Diffstat (limited to '')
-rw-r--r-- | include/video/display_timing.h | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/include/video/display_timing.h b/include/video/display_timing.h new file mode 100644 index 000000000..37a017607 --- /dev/null +++ b/include/video/display_timing.h @@ -0,0 +1,105 @@ +/* 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 |