struct pci9118_private {
        unsigned long iobase_a; /* base+size for AMCC chip */
-       unsigned int master;    /* master capable */
-       unsigned int usemux;    /* we want to use external multiplexor! */
+       unsigned int master:1;
+       unsigned int dma_doublebuf:1;
+       unsigned int ai_neverending:1;
+       unsigned int usedma:1;
+       unsigned int usemux:1;
        unsigned char ai_ctrl;
        unsigned char int_ctrl;
        unsigned char ai_cfg;
-       char ai_neverending;            /* we do unlimited AI */
        unsigned int ai_do;             /* what do AI? 0=nothing, 1 to 4 mode */
        unsigned int ai_act_scan;       /* how many scans we finished */
        unsigned int ai_n_realscanlen;  /*
                                                 * divisors for start of measure
                                                 * on external start
                                                 */
-       char dma_doublebuf;                     /* use double buffering */
        unsigned int dma_actbuf;                /* which buffer is used now */
        unsigned short *dmabuf_virt[2];         /*
                                                 * pointers to begin of
                                                 * bit field of external trigger
                                                 * users(0-AI, 1-AO, 2-DI, 3-DO)
                                                 */
-       unsigned char usedma;           /* =1 use DMA transfer and not INT */
        int softsshdelay;               /*
                                         * >0 use software S&H,
                                         * numer is requested delay in ns
                if (softsshdelay > 0)
                        if (ext_mux > 128)
                                ext_mux = 128;
-               devpriv->usemux = ext_mux;
+               devpriv->usemux = 1;
        } else {
                devpriv->usemux = 0;
        }
        s = &dev->subdevices[0];
        s->type         = COMEDI_SUBD_AI;
        s->subdev_flags = SDF_READABLE | SDF_COMMON | SDF_GROUND | SDF_DIFF;
-       s->n_chan       = (devpriv->usemux) ? devpriv->usemux : 16;
+       s->n_chan       = (devpriv->usemux) ? ext_mux : 16;
        s->maxdata      = board->ai_is_16bit ? 0xffff : 0x0fff;
        s->range_table  = board->is_hg ? &pci9118hg_ai_range
                                       : &pci9118_ai_range;