mmc: davinci_mmc: Use dma_request_chan() to requesting DMA channel

With the new dma_request_chan() the client driver does not need to look for
the DMA resource and it does not need to pass filter_fn anymore.
By switching to the new API the driver can now support deferred probing
against DMA.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
index 693144e..eb3ca9e 100644 (file)
--- a/drivers/mmc/host/davinci_mmc.c
+++ b/drivers/mmc/host/davinci_mmc.c
@@ -32,12 +32,10 @@
 #include <linux/delay.h>
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
-#include <linux/edma.h>
 #include <linux/mmc/mmc.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 
-#include <linux/platform_data/edma.h>
 #include <linux/platform_data/mmc-davinci.h>
 
 /*
@@ -202,7 +200,6 @@ struct mmc_davinci_host {
        u32 buffer_bytes_left;
        u32 bytes_left;
 
-       u32 rxdma, txdma;
        struct dma_chan *dma_tx;
        struct dma_chan *dma_rx;
        bool use_dma;
@@ -513,35 +510,20 @@ davinci_release_dma_channels(struct mmc_davinci_host *host)
 
 static int __init davinci_acquire_dma_channels(struct mmc_davinci_host *host)
 {
-       int r;
-       dma_cap_mask_t mask;
-
-       dma_cap_zero(mask);
-       dma_cap_set(DMA_SLAVE, mask);
-
-       host->dma_tx =
-               dma_request_slave_channel_compat(mask, edma_filter_fn,
-                               &host->txdma, mmc_dev(host->mmc), "tx");
-       if (!host->dma_tx) {
+       host->dma_tx = dma_request_chan(mmc_dev(host->mmc), "tx");
+       if (IS_ERR(host->dma_tx)) {
                dev_err(mmc_dev(host->mmc), "Can't get dma_tx channel\n");
-               return -ENODEV;
+               return PTR_ERR(host->dma_tx);
        }
 
-       host->dma_rx =
-               dma_request_slave_channel_compat(mask, edma_filter_fn,
-                               &host->rxdma, mmc_dev(host->mmc), "rx");
-       if (!host->dma_rx) {
+       host->dma_rx = dma_request_chan(mmc_dev(host->mmc), "rx");
+       if (IS_ERR(host->dma_rx)) {
                dev_err(mmc_dev(host->mmc), "Can't get dma_rx channel\n");
-               r = -ENODEV;
-               goto free_master_write;
+               dma_release_channel(host->dma_tx);
+               return PTR_ERR(host->dma_rx);
        }
 
        return 0;
-
-free_master_write:
-       dma_release_channel(host->dma_tx);
-
-       return r;
 }
 
 /*----------------------------------------------------------------------*/
@@ -1253,18 +1235,6 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
        host = mmc_priv(mmc);
        host->mmc = mmc;        /* Important */
 
-       r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
-       if (!r)
-               dev_warn(&pdev->dev, "RX DMA resource not specified\n");
-       else
-               host->rxdma = r->start;
-
-       r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
-       if (!r)
-               dev_warn(&pdev->dev, "TX DMA resource not specified\n");
-       else
-               host->txdma = r->start;
-
        host->mem_res = mem;
        host->base = ioremap(mem->start, mem_size);
        if (!host->base)
@@ -1291,8 +1261,13 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
        host->mmc_irq = irq;
        host->sdio_irq = platform_get_irq(pdev, 1);
 
-       if (host->use_dma && davinci_acquire_dma_channels(host) != 0)
-               host->use_dma = 0;
+       if (host->use_dma) {
+               ret = davinci_acquire_dma_channels(host);
+               if (ret == -EPROBE_DEFER)
+                       goto out;
+               else if (ret)
+                       host->use_dma = 0;
+       }
 
        /* REVISIT:  someday, support IRQ-driven card detection.  */
        mmc->caps |= MMC_CAP_NEEDS_POLL;