mtd: omap2: remove private DMA API implementation

Remove the private DMA API implementation from nand/omap2.c
making it use entirely the DMA engine API.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 26 insertions, 110 deletions

diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
index 2912d6c93635..e9309b3659e7 100644
--- a/drivers/mtd/nand/omap2.c
+++ b/drivers/mtd/nand/omap2.c
@@ -126,7 +126,6 @@ struct omap_nand_info {
         unsigned long                   phys_base;
         struct completion               comp;
         struct dma_chan                 *dma;
-        int                             dma_ch;
         int                             gpmc_irq;
         enum {
                 OMAP_NAND_IO_READ = 0,  /* read */
@@ -339,15 +338,9 @@ static void omap_write_buf_pref(struct mtd_info *mtd,
 }
 
 /*
- * omap_nand_dma_cb: callback on the completion of dma transfer
- * @lch: logical channel
- * @ch_satuts: channel status
+ * omap_nand_dma_callback: callback on the completion of dma transfer
  * @data: pointer to completion data structure
  */
-static void omap_nand_dma_cb(int lch, u16 ch_status, void *data)
-{
-        complete((struct completion *) data);
-}
 static void omap_nand_dma_callback(void *data)
 {
         complete((struct completion *) data);
@@ -365,17 +358,13 @@ static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr,
 {
         struct omap_nand_info *info = container_of(mtd,
                                         struct omap_nand_info, mtd);
+        struct dma_async_tx_descriptor *tx;
         enum dma_data_direction dir = is_write ? DMA_TO_DEVICE :
                                                         DMA_FROM_DEVICE;
-        dma_addr_t dma_addr;
-        int ret;
+        struct scatterlist sg;
         unsigned long tim, limit;
-
-        /* The fifo depth is 64 bytes max.
-         * But configure the FIFO-threahold to 32 to get a sync at each frame
-         * and frame length is 32 bytes.
-         */
-        int buf_len = len >> 6;
+        unsigned n;
+        int ret;
 
         if (addr >= high_memory) {
                 struct page *p1;
@@ -389,89 +378,33 @@ static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr,
                 addr = page_address(p1) + ((size_t)addr & ~PAGE_MASK);
         }
 
-        if (info->dma) {
-                struct dma_async_tx_descriptor *tx;
-                struct scatterlist sg;
-                unsigned n;
-
-                sg_init_one(&sg, addr, len);
-                n = dma_map_sg(info->dma->device->dev, &sg, 1, dir);
-                if (n == 0) {
-                        dev_err(&info->pdev->dev,
-                                "Couldn't DMA map a %d byte buffer\n", len);
-                        goto out_copy;
-                }
-
-                tx = dmaengine_prep_slave_sg(info->dma, &sg, n,
-                        is_write ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
-                        DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
-                if (!tx) {
-                        dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
-                        goto out_copy;
-                }
-                tx->callback = omap_nand_dma_callback;
-                tx->callback_param = &info->comp;
-                dmaengine_submit(tx);
-
-                /*  configure and start prefetch transfer */
-                ret = gpmc_prefetch_enable(info->gpmc_cs,
-                        PREFETCH_FIFOTHRESHOLD_MAX, 0x1, len, is_write);
-                if (ret) {
-                        /* PFPW engine is busy, use cpu copy method */
-                        dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
-                        goto out_copy;
-                }
-
-                init_completion(&info->comp);
-                dma_async_issue_pending(info->dma);
-
-                /* setup and start DMA using dma_addr */
-                wait_for_completion(&info->comp);
-                tim = 0;
-                limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
-                while (gpmc_read_status(GPMC_PREFETCH_COUNT) && (tim++ < limit))
-                        cpu_relax();
-
-                /* disable and stop the PFPW engine */
-                gpmc_prefetch_reset(info->gpmc_cs);
-
-                dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
-                return 0;
-        }
-
-        dma_addr = dma_map_single(&info->pdev->dev, addr, len, dir);
-        if (dma_mapping_error(&info->pdev->dev, dma_addr)) {
+        sg_init_one(&sg, addr, len);
+        n = dma_map_sg(info->dma->device->dev, &sg, 1, dir);
+        if (n == 0) {
                 dev_err(&info->pdev->dev,
                         "Couldn't DMA map a %d byte buffer\n", len);
                 goto out_copy;
         }
 
-        if (is_write) {
-            omap_set_dma_dest_params(info->dma_ch, 0, OMAP_DMA_AMODE_CONSTANT,
-                                                info->phys_base, 0, 0);
-            omap_set_dma_src_params(info->dma_ch, 0, OMAP_DMA_AMODE_POST_INC,
-                                                        dma_addr, 0, 0);
-            omap_set_dma_transfer_params(info->dma_ch, OMAP_DMA_DATA_TYPE_S32,
-                                        0x10, buf_len, OMAP_DMA_SYNC_FRAME,
-                                        OMAP24XX_DMA_GPMC, OMAP_DMA_DST_SYNC);
-        } else {
-            omap_set_dma_src_params(info->dma_ch, 0, OMAP_DMA_AMODE_CONSTANT,
-                                                info->phys_base, 0, 0);
-            omap_set_dma_dest_params(info->dma_ch, 0, OMAP_DMA_AMODE_POST_INC,
-                                                        dma_addr, 0, 0);
-            omap_set_dma_transfer_params(info->dma_ch, OMAP_DMA_DATA_TYPE_S32,
-                                        0x10, buf_len, OMAP_DMA_SYNC_FRAME,
-                                        OMAP24XX_DMA_GPMC, OMAP_DMA_SRC_SYNC);
-        }
-        /*  configure and start prefetch transfer */
+        tx = dmaengine_prep_slave_sg(info->dma, &sg, n,
+                is_write ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
+                DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+        if (!tx)
+                goto out_copy_unmap;
+
+        tx->callback = omap_nand_dma_callback;
+        tx->callback_param = &info->comp;
+        dmaengine_submit(tx);
+
+        /* configure and start prefetch transfer */
         ret = gpmc_prefetch_enable(info->gpmc_cs,
-                        PREFETCH_FIFOTHRESHOLD_MAX, 0x1, len, is_write);
+                PREFETCH_FIFOTHRESHOLD_MAX, 0x1, len, is_write);
         if (ret)
                 /* PFPW engine is busy, use cpu copy method */
                 goto out_copy_unmap;
 
         init_completion(&info->comp);
-        omap_start_dma(info->dma_ch);
+        dma_async_issue_pending(info->dma);
 
         /* setup and start DMA using dma_addr */
         wait_for_completion(&info->comp);
@@ -483,11 +416,11 @@ static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr,
         /* disable and stop the PFPW engine */
         gpmc_prefetch_reset(info->gpmc_cs);
 
-        dma_unmap_single(&info->pdev->dev, dma_addr, len, dir);
+        dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
         return 0;
 
 out_copy_unmap:
-        dma_unmap_single(&info->pdev->dev, dma_addr, len, dir);
+        dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
 out_copy:
         if (info->nand.options & NAND_BUSWIDTH_16)
                 is_write == 0 ? omap_read_buf16(mtd, (u_char *) addr, len)
@@ -1307,7 +1240,9 @@ static int __devinit omap_nand_probe(struct platform_device *pdev)
                 sig = OMAP24XX_DMA_GPMC;
                 info->dma = dma_request_channel(mask, omap_dma_filter_fn, &sig);
                 if (!info->dma) {
-                        dev_warn(&pdev->dev, "DMA engine request failed\n");
+                        dev_err(&pdev->dev, "DMA engine request failed\n");
+                        err = -ENXIO;
+                        goto out_release_mem_region;
                 } else {
                         struct dma_slave_config cfg;
                         int rc;
@@ -1327,22 +1262,6 @@ static int __devinit omap_nand_probe(struct platform_device *pdev)
                         }
                         info->nand.read_buf   = omap_read_buf_dma_pref;
                         info->nand.write_buf  = omap_write_buf_dma_pref;
-                        break;
-                }
-                err = omap_request_dma(OMAP24XX_DMA_GPMC, "NAND",
-                                omap_nand_dma_cb, &info->comp, &info->dma_ch);
-                if (err < 0) {
-                        info->dma_ch = -1;
-                        dev_err(&pdev->dev, "DMA request failed!\n");
-                        goto out_release_mem_region;
-                } else {
-                        omap_set_dma_dest_burst_mode(info->dma_ch,
-                                        OMAP_DMA_DATA_BURST_16);
-                        omap_set_dma_src_burst_mode(info->dma_ch,
-                                        OMAP_DMA_DATA_BURST_16);
-
-                        info->nand.read_buf   = omap_read_buf_dma_pref;
-                        info->nand.write_buf  = omap_write_buf_dma_pref;
                 }
                 break;
 
@@ -1460,9 +1379,6 @@ static int omap_nand_remove(struct platform_device *pdev)
         omap3_free_bch(&info->mtd);
 
         platform_set_drvdata(pdev, NULL);
-        if (info->dma_ch != -1)
-                omap_free_dma(info->dma_ch);
-
         if (info->dma)
                 dma_release_channel(info->dma);