GPR_MS_MIC2
ac_gpr_toggle(ctrl, GPR_MS_MIC2, value & 2);
ac_clr(ac, AC97_GENERAL_PURPOSE_REGISTER, GPR_MS_MIC2);
ac_set(ac, AC97_GENERAL_PURPOSE_REGISTER, GPR_MS_MIC2);
ac_clr(ac, AC97_GENERAL_PURPOSE_REGISTER, GPR_MS_MIC2);