CODA_REG_BIT_WR_PTR
coda_write(dev, bitstream_buf, CODA_REG_BIT_WR_PTR(ctx->reg_idx));
wr_ptr = coda_read(dev, CODA_REG_BIT_WR_PTR(ctx->reg_idx));
coda_write(dev, wr_ptr, CODA_REG_BIT_WR_PTR(ctx->reg_idx));
coda_write(dev, wr_ptr, CODA_REG_BIT_WR_PTR(ctx->reg_idx));
*size = coda_read(dev, CODA_REG_BIT_WR_PTR(ctx->reg_idx)) -