PTBA
emu10k_write_reg(devc, PTBA, 0, devc->pt_paddr);
tmp = emu10k_read_reg(devc, PTBA, 0);
emu10k_write_reg(devc, PTBA, 0, 0);
write_chan(dev, PTBA, i, 0);
write_reg(dev, PTBA, i, 0);
write_reg(dev, PTBA, i, 0);