mmc: s3cmci: port DMA code to dmaengine API

Utilise new s3c24xx-dma dmaengine driver for DMA ops.

Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

3 files changed, 52 insertions, 142 deletions

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index a5652548230a..9682ad1e94b5 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -440,6 +440,7 @@ config MMC_SPI
 config MMC_S3C
         tristate "Samsung S3C SD/MMC Card Interface support"
         depends on ARCH_S3C24XX
+        depends on S3C24XX_DMAC
         help
           This selects a driver for the MCI interface found in
           Samsung's S3C2410, S3C2412, S3C2440, S3C2442 CPUs.
@@ -477,15 +478,6 @@ config MMC_S3C_DMA
           working properly and needs to be debugged before this
           option is useful.
 
-config MMC_S3C_PIODMA
-        bool "Support for both PIO and DMA"
-        help
-          Compile both the PIO and DMA transfer routines into the
-          driver and let the platform select at run-time which one
-          is best.
-
-          See notes for the DMA option.
-
 endchoice
 
 config MMC_SDRICOH_CS
diff --git a/drivers/mmc/host/s3cmci.c b/drivers/mmc/host/s3cmci.c
index 501ec210780c..e5516a226362 100644
--- a/drivers/mmc/host/s3cmci.c
+++ b/drivers/mmc/host/s3cmci.c
@@ -12,6 +12,7 @@
  */
 
 #include <linux/module.h>
+#include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
 #include <linux/clk.h>
 #include <linux/mmc/host.h>
@@ -27,6 +28,7 @@
 #include <mach/dma.h>
 #include <mach/gpio-samsung.h>
 
+#include <linux/platform_data/dma-s3c24xx.h>
 #include <linux/platform_data/mmc-s3cmci.h>
 
 #include "s3cmci.h"
@@ -140,10 +142,6 @@ static const int dbgmap_debug = dbg_err | dbg_debug;
                 dev_dbg(&host->pdev->dev, args);  \
         } while (0)
 
-static struct s3c2410_dma_client s3cmci_dma_client = {
-        .name           = "s3c-mci",
-};
-
 static void finalize_request(struct s3cmci_host *host);
 static void s3cmci_send_request(struct mmc_host *mmc);
 static void s3cmci_reset(struct s3cmci_host *host);
@@ -256,25 +254,8 @@ static inline bool s3cmci_host_usedma(struct s3cmci_host *host)
 {
 #ifdef CONFIG_MMC_S3C_PIO
         return false;
-#elif defined(CONFIG_MMC_S3C_DMA)
+#else /* CONFIG_MMC_S3C_DMA */
         return true;
-#else
-        return host->dodma;
-#endif
-}
-
-/**
- * s3cmci_host_canpio - return true if host has pio code available
- *
- * Return true if the driver has been compiled with the PIO support code
- * available.
- */
-static inline bool s3cmci_host_canpio(void)
-{
-#ifdef CONFIG_MMC_S3C_PIO
-        return true;
-#else
-        return false;
 #endif
 }
 
@@ -841,60 +822,24 @@ static irqreturn_t s3cmci_irq_cd(int irq, void *dev_id)
         return IRQ_HANDLED;
 }
 
-static void s3cmci_dma_done_callback(struct s3c2410_dma_chan *dma_ch,
-                                     void *buf_id, int size,
-                                     enum s3c2410_dma_buffresult result)
+static void s3cmci_dma_done_callback(void *arg)
 {
-        struct s3cmci_host *host = buf_id;
+        struct s3cmci_host *host = arg;
         unsigned long iflags;
-        u32 mci_csta, mci_dsta, mci_fsta, mci_dcnt;
-
-        mci_csta = readl(host->base + S3C2410_SDICMDSTAT);
-        mci_dsta = readl(host->base + S3C2410_SDIDSTA);
-        mci_fsta = readl(host->base + S3C2410_SDIFSTA);
-        mci_dcnt = readl(host->base + S3C2410_SDIDCNT);
 
         BUG_ON(!host->mrq);
         BUG_ON(!host->mrq->data);
-        BUG_ON(!host->dmatogo);
 
         spin_lock_irqsave(&host->complete_lock, iflags);
 
-        if (result != S3C2410_RES_OK) {
-                dbg(host, dbg_fail, "DMA FAILED: csta=0x%08x dsta=0x%08x "
-                        "fsta=0x%08x dcnt:0x%08x result:0x%08x toGo:%u\n",
-                        mci_csta, mci_dsta, mci_fsta,
-                        mci_dcnt, result, host->dmatogo);
-
-                goto fail_request;
-        }
-
-        host->dmatogo--;
-        if (host->dmatogo) {
-                dbg(host, dbg_dma, "DMA DONE  Size:%i DSTA:[%08x] "
-                        "DCNT:[%08x] toGo:%u\n",
-                        size, mci_dsta, mci_dcnt, host->dmatogo);
-
-                goto out;
-        }
-
-        dbg(host, dbg_dma, "DMA FINISHED Size:%i DSTA:%08x DCNT:%08x\n",
-                size, mci_dsta, mci_dcnt);
+        dbg(host, dbg_dma, "DMA FINISHED\n");
 
         host->dma_complete = 1;
         host->complete_what = COMPLETION_FINALIZE;
 
-out:
         tasklet_schedule(&host->pio_tasklet);
         spin_unlock_irqrestore(&host->complete_lock, iflags);
-        return;
 
-fail_request:
-        host->mrq->data->error = -EINVAL;
-        host->complete_what = COMPLETION_FINALIZE;
-        clear_imask(host);
-
-        goto out;
 }
 
 static void finalize_request(struct s3cmci_host *host)
@@ -966,7 +911,7 @@ static void finalize_request(struct s3cmci_host *host)
          * DMA channel and the fifo to clear out any garbage. */
         if (mrq->data->error != 0) {
                 if (s3cmci_host_usedma(host))
-                        s3c2410_dma_ctrl(host->dma, S3C2410_DMAOP_FLUSH);
+                        dmaengine_terminate_all(host->dma);
 
                 if (host->is2440) {
                         /* Clear failure register and reset fifo. */
@@ -992,29 +937,6 @@ request_done:
         mmc_request_done(host->mmc, mrq);
 }
 
-static void s3cmci_dma_setup(struct s3cmci_host *host,
-                             enum dma_data_direction source)
-{
-        static enum dma_data_direction last_source = -1;
-        static int setup_ok;
-
-        if (last_source == source)
-                return;
-
-        last_source = source;
-
-        s3c2410_dma_devconfig(host->dma, source,
-                              host->mem->start + host->sdidata);
-
-        if (!setup_ok) {
-                s3c2410_dma_config(host->dma, 4);
-                s3c2410_dma_set_buffdone_fn(host->dma,
-                                            s3cmci_dma_done_callback);
-                s3c2410_dma_setflags(host->dma, S3C2410_DMAF_AUTOSTART);
-                setup_ok = 1;
-        }
-}
-
 static void s3cmci_send_command(struct s3cmci_host *host,
                                         struct mmc_command *cmd)
 {
@@ -1162,43 +1084,45 @@ static int s3cmci_prepare_pio(struct s3cmci_host *host, struct mmc_data *data)
 
 static int s3cmci_prepare_dma(struct s3cmci_host *host, struct mmc_data *data)
 {
-        int dma_len, i;
         int rw = data->flags & MMC_DATA_WRITE;
+        struct dma_async_tx_descriptor *desc;
+        struct dma_slave_config conf = {
+                .src_addr = host->mem->start + host->sdidata,
+                .dst_addr = host->mem->start + host->sdidata,
+                .src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
+                .dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
+        };
 
         BUG_ON((data->flags & BOTH_DIR) == BOTH_DIR);
 
-        s3cmci_dma_setup(host, rw ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
-        s3c2410_dma_ctrl(host->dma, S3C2410_DMAOP_FLUSH);
-
-        dma_len = dma_map_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
-                             rw ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
-
-        if (dma_len == 0)
-                return -ENOMEM;
-
-        host->dma_complete = 0;
-        host->dmatogo = dma_len;
-
-        for (i = 0; i < dma_len; i++) {
-                int res;
-
-                dbg(host, dbg_dma, "enqueue %i: %08x@%u\n", i,
-                    sg_dma_address(&data->sg[i]),
-                    sg_dma_len(&data->sg[i]));
+        /* Restore prescaler value */
+        writel(host->prescaler, host->base + S3C2410_SDIPRE);
 
-                res = s3c2410_dma_enqueue(host->dma, host,
-                                          sg_dma_address(&data->sg[i]),
-                                          sg_dma_len(&data->sg[i]));
+        if (!rw)
+                conf.direction = DMA_DEV_TO_MEM;
+        else
+                conf.direction = DMA_MEM_TO_DEV;
 
-                if (res) {
-                        s3c2410_dma_ctrl(host->dma, S3C2410_DMAOP_FLUSH);
-                        return -EBUSY;
-                }
-        }
+        dma_map_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
+                             rw ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
 
-        s3c2410_dma_ctrl(host->dma, S3C2410_DMAOP_START);
+        dmaengine_slave_config(host->dma, &conf);
+        desc = dmaengine_prep_slave_sg(host->dma, data->sg, data->sg_len,
+                conf.direction,
+                DMA_CTRL_ACK | DMA_PREP_INTERRUPT);
+        if (!desc)
+                goto unmap_exit;
+        desc->callback = s3cmci_dma_done_callback;
+        desc->callback_param = host;
+        dmaengine_submit(desc);
+        dma_async_issue_pending(host->dma);
 
         return 0;
+
+unmap_exit:
+        dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
+                             rw ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
+        return -ENOMEM;
 }
 
 static void s3cmci_send_request(struct mmc_host *mmc)
@@ -1676,10 +1600,6 @@ static int s3cmci_probe(struct platform_device *pdev)
         host->complete_what     = COMPLETION_NONE;
         host->pio_active        = XFER_NONE;
 
-#ifdef CONFIG_MMC_S3C_PIODMA
-        host->dodma             = host->pdata->use_dma;
-#endif
-
         host->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         if (!host->mem) {
                 dev_err(&pdev->dev,
@@ -1765,17 +1685,17 @@ static int s3cmci_probe(struct platform_device *pdev)
         /* depending on the dma state, get a dma channel to use. */
 
         if (s3cmci_host_usedma(host)) {
-                host->dma = s3c2410_dma_request(DMACH_SDI, &s3cmci_dma_client,
-                                                host);
-                if (host->dma < 0) {
+                dma_cap_mask_t mask;
+
+                dma_cap_zero(mask);
+                dma_cap_set(DMA_SLAVE, mask);
+
+                host->dma = dma_request_slave_channel_compat(mask,
+                        s3c24xx_dma_filter, (void *)DMACH_SDI, &pdev->dev, "rx-tx");
+                if (!host->dma) {
                         dev_err(&pdev->dev, "cannot get DMA channel.\n");
-                        if (!s3cmci_host_canpio()) {
-                                ret = -EBUSY;
-                                goto probe_free_gpio_wp;
-                        } else {
-                                dev_warn(&pdev->dev, "falling back to PIO.\n");
-                                host->dodma = 0;
-                        }
+                        ret = -EBUSY;
+                        goto probe_free_gpio_wp;
                 }
         }
 
@@ -1816,7 +1736,7 @@ static int s3cmci_probe(struct platform_device *pdev)
         mmc->max_segs           = 128;
 
         dbg(host, dbg_debug,
-            "probe: mode:%s mapped mci_base:%p irq:%u irq_cd:%u dma:%u.\n",
+            "probe: mode:%s mapped mci_base:%p irq:%u irq_cd:%u dma:%p.\n",
             (host->is2440?"2440":""),
             host->base, host->irq, host->irq_cd, host->dma);
 
@@ -1852,7 +1772,7 @@ static int s3cmci_probe(struct platform_device *pdev)
 
  probe_free_dma:
         if (s3cmci_host_usedma(host))
-                s3c2410_dma_free(host->dma, &s3cmci_dma_client);
+                dma_release_channel(host->dma);
 
  probe_free_gpio_wp:
         if (!host->pdata->no_wprotect)
@@ -1914,7 +1834,7 @@ static int s3cmci_remove(struct platform_device *pdev)
         tasklet_disable(&host->pio_tasklet);
 
         if (s3cmci_host_usedma(host))
-                s3c2410_dma_free(host->dma, &s3cmci_dma_client);
+                dma_release_channel(host->dma);
 
         free_irq(host->irq, host);
 
diff --git a/drivers/mmc/host/s3cmci.h b/drivers/mmc/host/s3cmci.h
index c76b53dbeb61..cc2e46cb5c64 100644
--- a/drivers/mmc/host/s3cmci.h
+++ b/drivers/mmc/host/s3cmci.h
@@ -26,7 +26,7 @@ struct s3cmci_host {
         void __iomem            *base;
         int                     irq;
         int                     irq_cd;
-        int                     dma;
+        struct dma_chan         *dma;
 
         unsigned long           clk_rate;
         unsigned long           clk_div;
@@ -36,8 +36,6 @@ struct s3cmci_host {
         int                     is2440;
         unsigned                sdiimsk;
         unsigned                sdidata;
-        int                     dodma;
-        int                     dmatogo;
 
         bool                    irq_disabled;
         bool                    irq_enabled;