typhoon_shared
#define shared_offset(x) offsetof(struct typhoon_shared, x)
memset(tp->shared, 0, sizeof(struct typhoon_shared));
shared = dma_alloc_coherent(&pdev->dev, sizeof(struct typhoon_shared),
dma_free_coherent(&pdev->dev, sizeof(struct typhoon_shared), shared,
dma_free_coherent(&pdev->dev, sizeof(struct typhoon_shared),
struct typhoon_shared * shared;