}
 #endif
 
+static void ahc_linux_get_signalling(struct Scsi_Host *shost)
+{
+       struct ahc_softc *ahc = *(struct ahc_softc **)shost->hostdata;
+       u8 mode = ahc_inb(ahc, SBLKCTL);
+
+       if (mode & ENAB40)
+               spi_signalling(shost) = SPI_SIGNAL_LVD;
+       else if (mode & ENAB20)
+               spi_signalling(shost) = 
+                       ahc->features & AHC_HVD ?
+                       SPI_SIGNAL_HVD :
+                       SPI_SIGNAL_SE;
+       else
+               spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
+}
+
 static struct spi_function_template ahc_linux_transport_functions = {
        .set_offset     = ahc_linux_set_offset,
        .show_offset    = 1,
        .set_qas        = ahc_linux_set_qas,
        .show_qas       = 1,
 #endif
+       .get_signalling = ahc_linux_get_signalling,
 };
 
 
 
 static ahc_device_setup_t ahc_aic7860_setup;
 static ahc_device_setup_t ahc_apa1480_setup;
 static ahc_device_setup_t ahc_aic7870_setup;
+static ahc_device_setup_t ahc_aic7870h_setup;
 static ahc_device_setup_t ahc_aha394X_setup;
+static ahc_device_setup_t ahc_aha394Xh_setup;
 static ahc_device_setup_t ahc_aha494X_setup;
+static ahc_device_setup_t ahc_aha494Xh_setup;
 static ahc_device_setup_t ahc_aha398X_setup;
 static ahc_device_setup_t ahc_aic7880_setup;
+static ahc_device_setup_t ahc_aic7880h_setup;
 static ahc_device_setup_t ahc_aha2940Pro_setup;
 static ahc_device_setup_t ahc_aha394XU_setup;
+static ahc_device_setup_t ahc_aha394XUh_setup;
 static ahc_device_setup_t ahc_aha398XU_setup;
 static ahc_device_setup_t ahc_aic7890_setup;
 static ahc_device_setup_t ahc_aic7892_setup;
 static ahc_device_setup_t ahc_aic7895_setup;
+static ahc_device_setup_t ahc_aic7895h_setup;
 static ahc_device_setup_t ahc_aic7896_setup;
 static ahc_device_setup_t ahc_aic7899_setup;
 static ahc_device_setup_t ahc_aha29160C_setup;
                ID_AHA_2944,
                ID_ALL_MASK,
                "Adaptec 2944 SCSI adapter",
-               ahc_aic7870_setup
+               ahc_aic7870h_setup
        },
        {
                ID_AHA_3944,
                ID_ALL_MASK,
                "Adaptec 3944 SCSI adapter",
-               ahc_aha394X_setup
+               ahc_aha394Xh_setup
        },
        {
                ID_AHA_4944,
                ID_ALL_MASK,
                "Adaptec 4944 SCSI adapter",
-               ahc_aha494X_setup
+               ahc_aha494Xh_setup
        },
        /* aic7880 based controllers */
        {
                ID_AHA_2944U & ID_DEV_VENDOR_MASK,
                ID_DEV_VENDOR_MASK,
                "Adaptec 2944 Ultra SCSI adapter",
-               ahc_aic7880_setup
+               ahc_aic7880h_setup
        },
        {
                ID_AHA_3944U & ID_DEV_VENDOR_MASK,
                ID_DEV_VENDOR_MASK,
                "Adaptec 3944 Ultra SCSI adapter",
-               ahc_aha394XU_setup
+               ahc_aha394XUh_setup
        },
        {
                ID_AHA_398XU & ID_DEV_VENDOR_MASK,
                ID_AHA_4944U & ID_DEV_VENDOR_MASK,
                ID_DEV_VENDOR_MASK,
                "Adaptec 4944 Ultra SCSI adapter",
-               ahc_aic7880_setup
+               ahc_aic7880h_setup
        },
        {
                ID_AHA_2930U & ID_DEV_VENDOR_MASK,
                ID_AHA_3944AU,
                ID_ALL_MASK,
                "Adaptec 3944A Ultra SCSI adapter",
-               ahc_aic7895_setup
+               ahc_aic7895h_setup
        },
        {
                ID_AIC7895_ARO,
        return (0);
 }
 
+static int
+ahc_aic7870h_setup(struct ahc_softc *ahc)
+{
+       int error = ahc_aic7870_setup(ahc);
+
+       ahc->features |= AHC_HVD;
+
+       return error;
+}
+
 static int
 ahc_aha394X_setup(struct ahc_softc *ahc)
 {
        return (error);
 }
 
+static int
+ahc_aha394Xh_setup(struct ahc_softc *ahc)
+{
+       int error = ahc_aha394X_setup(ahc);
+
+       ahc->features |= AHC_HVD;
+
+       return error;
+}
+
 static int
 ahc_aha398X_setup(struct ahc_softc *ahc)
 {
        return (error);
 }
 
+static int
+ahc_aha494Xh_setup(struct ahc_softc *ahc)
+{
+       int error = ahc_aha494X_setup(ahc);
+
+       ahc->features |= AHC_HVD;
+
+       return error;
+}
+
 static int
 ahc_aic7880_setup(struct ahc_softc *ahc)
 {
        return (0);
 }
 
+static int
+ahc_aic7880h_setup(struct ahc_softc *ahc)
+{
+       int error = ahc_aic7880_setup(ahc);
+
+       ahc->features |= AHC_HVD;
+
+       return error;
+}
+
+
 static int
 ahc_aha2940Pro_setup(struct ahc_softc *ahc)
 {
        return (error);
 }
 
+static int
+ahc_aha394XUh_setup(struct ahc_softc *ahc)
+{
+       int error = ahc_aha394XU_setup(ahc);
+
+       ahc->features |= AHC_HVD;
+
+       return error;
+}
+
 static int
 ahc_aha398XU_setup(struct ahc_softc *ahc)
 {
        return (0);
 }
 
+static int
+ahc_aic7895h_setup(struct ahc_softc *ahc)
+{
+       int error = ahc_aic7895_setup(ahc);
+
+       ahc->features |= AHC_HVD;
+
+       return error;
+}
+
 static int
 ahc_aic7896_setup(struct ahc_softc *ahc)
 {