MXR_INT_STATUS
mixer_reg_writemask(ctx, MXR_INT_STATUS, ~0,
DUMPREG(MXR_INT_STATUS);
val = mixer_reg_read(ctx, MXR_INT_STATUS);
mixer_reg_write(ctx, MXR_INT_STATUS, val);
mixer_reg_writemask(mixer_ctx, MXR_INT_STATUS, ~0, MXR_INT_CLEAR_VSYNC);
mixer_reg_writemask(mixer_ctx, MXR_INT_STATUS, ~0, MXR_INT_CLEAR_VSYNC);