// SPDX-License-Identifier: MIT
#include "hdmi.h"

void pack_hdmi_infoframe(struct packed_hdmi_infoframe *packed_frame,
                         u8 *raw_frame, ssize_t len)
{
        u32 header = 0;
        u32 subpack0_low = 0;
        u32 subpack0_high = 0;
        u32 subpack1_low = 0;
        u32 subpack1_high = 0;

        switch (len) {
                /*
                 * "When in doubt, use brute force."
                 *     -- Ken Thompson.
                 */
        default:
                /*
                 * We presume that no valid frame is longer than 17
                 * octets, including header...  And truncate to that
                 * if it's longer.
                 */
        case 17:
                subpack1_high = (raw_frame[16] << 16);
                fallthrough;
        case 16:
                subpack1_high |= (raw_frame[15] << 8);
                fallthrough;
        case 15:
                subpack1_high |= raw_frame[14];
                fallthrough;
        case 14:
                subpack1_low = (raw_frame[13] << 24);
                fallthrough;
        case 13:
                subpack1_low |= (raw_frame[12] << 16);
                fallthrough;
        case 12:
                subpack1_low |= (raw_frame[11] << 8);
                fallthrough;
        case 11:
                subpack1_low |= raw_frame[10];
                fallthrough;
        case 10:
                subpack0_high = (raw_frame[9] << 16);
                fallthrough;
        case 9:
                subpack0_high |= (raw_frame[8] << 8);
                fallthrough;
        case 8:
                subpack0_high |= raw_frame[7];
                fallthrough;
        case 7:
                subpack0_low = (raw_frame[6] << 24);
                fallthrough;
        case 6:
                subpack0_low |= (raw_frame[5] << 16);
                fallthrough;
        case 5:
                subpack0_low |= (raw_frame[4] << 8);
                fallthrough;
        case 4:
                subpack0_low |= raw_frame[3];
                fallthrough;
        case 3:
                header = (raw_frame[2] << 16);
                fallthrough;
        case 2:
                header |= (raw_frame[1] << 8);
                fallthrough;
        case 1:
                header |= raw_frame[0];
                fallthrough;
        case 0:
                break;
        }

        packed_frame->header = header;
        packed_frame->subpack0_low = subpack0_low;
        packed_frame->subpack0_high = subpack0_high;
        packed_frame->subpack1_low = subpack1_low;
        packed_frame->subpack1_high = subpack1_high;
}