Merge tag 'for-linus-v3.10-rc5' of git://oss.sgi.com/xfs/xfs

[linux-2.6-microblaze.git] / drivers / staging / comedi / comedi_buf.c

diff --git a/drivers/staging/comedi/comedi_buf.c b/drivers/staging/comedi/comedi_buf.c
index ca70990..d4be0e6 100644 (file)
--- a/drivers/staging/comedi/comedi_buf.c
+++ b/drivers/staging/comedi/comedi_buf.c
@@ -51,10 +51,12 @@ static void __comedi_buf_free(struct comedi_device *dev,
                        clear_bit(PG_reserved,
                                  &(virt_to_page(buf->virt_addr)->flags));
                        if (s->async_dma_dir != DMA_NONE) {
+#ifdef CONFIG_HAS_DMA
                                dma_free_coherent(dev->hw_dev,
                                                  PAGE_SIZE,
                                                  buf->virt_addr,
                                                  buf->dma_addr);
+#endif
                        } else {
                                free_page((unsigned long)buf->virt_addr);
                        }
@@ -74,6 +76,12 @@ static void __comedi_buf_alloc(struct comedi_device *dev,
        struct comedi_buf_page *buf;
        unsigned i;
 
+       if (!IS_ENABLED(CONFIG_HAS_DMA) && s->async_dma_dir != DMA_NONE) {
+               dev_err(dev->class_dev,
+                       "dma buffer allocation not supported\n");
+               return;
+       }
+
        async->buf_page_list = vzalloc(sizeof(*buf) * n_pages);
        if (async->buf_page_list)
                pages = vmalloc(sizeof(struct page *) * n_pages);
@@ -84,11 +92,15 @@ static void __comedi_buf_alloc(struct comedi_device *dev,
        for (i = 0; i < n_pages; i++) {
                buf = &async->buf_page_list[i];
                if (s->async_dma_dir != DMA_NONE)
+#ifdef CONFIG_HAS_DMA
                        buf->virt_addr = dma_alloc_coherent(dev->hw_dev,
                                                            PAGE_SIZE,
                                                            &buf->dma_addr,
                                                            GFP_KERNEL |
                                                            __GFP_COMP);
+#else
+                       break;
+#endif
                else
                        buf->virt_addr = (void *)get_zeroed_page(GFP_KERNEL);
                if (!buf->virt_addr)