For now the header file includes a single method to retreive the bpc from the bus format. The supported MEDIA_BUS_* codes are the ones used for the current panels in DRM. The list can be extended as there are a need for more formats.
Signed-off-by: Sam Ravnborg sam@ravnborg.org --- include/drm/media-bus-format.h | 53 ++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) create mode 100644 include/drm/media-bus-format.h
diff --git a/include/drm/media-bus-format.h b/include/drm/media-bus-format.h new file mode 100644 index 000000000000..d4d18f19a70f --- /dev/null +++ b/include/drm/media-bus-format.h @@ -0,0 +1,53 @@ +/* SPDX-License-Identifier: MIT */ +/* + * Copyright © 2022 Sam Ravnborg + */ + +#ifndef __LINUX_DRM_MEDIA_BUS_FORMAT +#define __LINUX_DRM_MEDIA_BUS_FORMAT + +#include <linux/bug.h> +#include <linux/media-bus-format.h> +#include <linux/types.h> + +/** + * media_bus_format_to_bpc - The bits per color channel for the bus_format + * + * Based on the supplied bus_format return the maximum number of bits + * per color channel. + * + * RETURNS + * The number of bits per color channel, or -EINVAL if the bus_format + * is unknown. + */ +static inline int media_bus_format_to_bpc(u32 bus_format) +{ + switch (bus_format) { + /* DPI */ + case MEDIA_BUS_FMT_RGB565_1X16: + case MEDIA_BUS_FMT_RGB666_1X18: + return 6; + + /* DPI */ + case MEDIA_BUS_FMT_RGB888_1X24: + case MEDIA_BUS_FMT_RGB888_3X8: + case MEDIA_BUS_FMT_RGB888_3X8_DELTA: + case MEDIA_BUS_FMT_Y8_1X8: + return 8; + + /* LVDS */ + case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG: + return 6; + + /* LVDS */ + case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA: + case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG: + return 8; + + default: + WARN(1, "Unknown MEDIA_BUS format %d\n", bus_format); + return -EINVAL; + } +} + +#endif