unsigned int maxsize;
 
        if (is_isoc)
-               maxsize = hs_ep->dir_in ? DEV_DMA_ISOC_TX_NBYTES_LIMIT :
-                                          DEV_DMA_ISOC_RX_NBYTES_LIMIT;
+               maxsize = (hs_ep->dir_in ? DEV_DMA_ISOC_TX_NBYTES_LIMIT :
+                                          DEV_DMA_ISOC_RX_NBYTES_LIMIT) *
+                                          MAX_DMA_DESC_NUM_HS_ISOC;
        else
-               maxsize = DEV_DMA_NBYTES_LIMIT;
-
-       /* Above size of one descriptor was chosen, multiple it */
-       maxsize *= MAX_DMA_DESC_NUM_GENERIC;
+               maxsize = DEV_DMA_NBYTES_LIMIT * MAX_DMA_DESC_NUM_GENERIC;
 
        return maxsize;
 }
 
        /* Update index of last configured entry in the chain */
        hs_ep->next_desc++;
-       if (hs_ep->next_desc >= MAX_DMA_DESC_NUM_GENERIC)
+       if (hs_ep->next_desc >= MAX_DMA_DESC_NUM_HS_ISOC)
                hs_ep->next_desc = 0;
 
        return 0;
        }
 
        /* Initialize descriptor chain by Host Busy status */
-       for (i = 0; i < MAX_DMA_DESC_NUM_GENERIC; i++) {
+       for (i = 0; i < MAX_DMA_DESC_NUM_HS_ISOC; i++) {
                desc = &hs_ep->desc_list[i];
                desc->status = 0;
                desc->status |= (DEV_DMA_BUFF_STS_HBUSY
                dwc2_hsotg_complete_request(hsotg, hs_ep, hs_req, 0);
 
                hs_ep->compl_desc++;
-               if (hs_ep->compl_desc > (MAX_DMA_DESC_NUM_GENERIC - 1))
+               if (hs_ep->compl_desc > (MAX_DMA_DESC_NUM_HS_ISOC - 1))
                        hs_ep->compl_desc = 0;
                desc_sts = hs_ep->desc_list[hs_ep->compl_desc].status;
        }
        unsigned int i, val, size;
        int ret = 0;
        unsigned char ep_type;
+       int desc_num;
 
        dev_dbg(hsotg->dev,
                "%s: ep %s: a 0x%02x, attr 0x%02x, mps 0x%04x, intr %d\n",
        dev_dbg(hsotg->dev, "%s: read DxEPCTL=0x%08x from 0x%08x\n",
                __func__, epctrl, epctrl_reg);
 
+       if (using_desc_dma(hsotg) && ep_type == USB_ENDPOINT_XFER_ISOC)
+               desc_num = MAX_DMA_DESC_NUM_HS_ISOC;
+       else
+               desc_num = MAX_DMA_DESC_NUM_GENERIC;
+
        /* Allocate DMA descriptor chain for non-ctrl endpoints */
        if (using_desc_dma(hsotg) && !hs_ep->desc_list) {
                hs_ep->desc_list = dmam_alloc_coherent(hsotg->dev,
-                       MAX_DMA_DESC_NUM_GENERIC *
-                       sizeof(struct dwc2_dma_desc),
+                       desc_num * sizeof(struct dwc2_dma_desc),
                        &hs_ep->desc_list_dma, GFP_ATOMIC);
                if (!hs_ep->desc_list) {
                        ret = -ENOMEM;
 
 error2:
        if (ret && using_desc_dma(hsotg) && hs_ep->desc_list) {
-               dmam_free_coherent(hsotg->dev, MAX_DMA_DESC_NUM_GENERIC *
+               dmam_free_coherent(hsotg->dev, desc_num *
                        sizeof(struct dwc2_dma_desc),
                        hs_ep->desc_list, hs_ep->desc_list_dma);
                hs_ep->desc_list = NULL;