spi: davinci: Use dma_request_chan() for 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: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-davinci.c b/drivers/spi/spi-davinci.c
index fddb7a3..d36c11b 100644 (file)
--- a/drivers/spi/spi-davinci.c
+++ b/drivers/spi/spi-davinci.c
@@ -23,7 +23,6 @@
 #include <linux/clk.h>
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
-#include <linux/edma.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/of_gpio.h>
@@ -33,8 +32,6 @@
 
 #include <linux/platform_data/spi-davinci.h>
 
-#define SPI_NO_RESOURCE                ((resource_size_t)-1)
-
 #define CS_DEFAULT     0xFF
 
 #define SPIFMT_PHASE_MASK      BIT(16)
@@ -130,8 +127,6 @@ struct davinci_spi {
 
        struct dma_chan         *dma_rx;
        struct dma_chan         *dma_tx;
-       int                     dma_rx_chnum;
-       int                     dma_tx_chnum;
 
        struct davinci_spi_platform_data pdata;
 
@@ -797,35 +792,19 @@ static irqreturn_t davinci_spi_irq(s32 irq, void *data)
 
 static int davinci_spi_request_dma(struct davinci_spi *dspi)
 {
-       dma_cap_mask_t mask;
        struct device *sdev = dspi->bitbang.master->dev.parent;
-       int r;
-
-       dma_cap_zero(mask);
-       dma_cap_set(DMA_SLAVE, mask);
 
-       dspi->dma_rx = dma_request_channel(mask, edma_filter_fn,
-                                          &dspi->dma_rx_chnum);
-       if (!dspi->dma_rx) {
-               dev_err(sdev, "request RX DMA channel failed\n");
-               r = -ENODEV;
-               goto rx_dma_failed;
-       }
+       dspi->dma_rx = dma_request_chan(sdev, "rx");
+       if (IS_ERR(dspi->dma_rx))
+               return PTR_ERR(dspi->dma_rx);
 
-       dspi->dma_tx = dma_request_channel(mask, edma_filter_fn,
-                                          &dspi->dma_tx_chnum);
-       if (!dspi->dma_tx) {
-               dev_err(sdev, "request TX DMA channel failed\n");
-               r = -ENODEV;
-               goto tx_dma_failed;
+       dspi->dma_tx = dma_request_chan(sdev, "tx");
+       if (IS_ERR(dspi->dma_tx)) {
+               dma_release_channel(dspi->dma_rx);
+               return PTR_ERR(dspi->dma_tx);
        }
 
        return 0;
-
-tx_dma_failed:
-       dma_release_channel(dspi->dma_rx);
-rx_dma_failed:
-       return r;
 }
 
 #if defined(CONFIG_OF)
@@ -936,8 +915,6 @@ static int davinci_spi_probe(struct platform_device *pdev)
        struct davinci_spi *dspi;
        struct davinci_spi_platform_data *pdata;
        struct resource *r;
-       resource_size_t dma_rx_chan = SPI_NO_RESOURCE;
-       resource_size_t dma_tx_chan = SPI_NO_RESOURCE;
        int ret = 0;
        u32 spipc0;
 
@@ -1044,27 +1021,15 @@ static int davinci_spi_probe(struct platform_device *pdev)
                }
        }
 
-       r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
-       if (r)
-               dma_rx_chan = r->start;
-       r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
-       if (r)
-               dma_tx_chan = r->start;
-
        dspi->bitbang.txrx_bufs = davinci_spi_bufs;
-       if (dma_rx_chan != SPI_NO_RESOURCE &&
-           dma_tx_chan != SPI_NO_RESOURCE) {
-               dspi->dma_rx_chnum = dma_rx_chan;
-               dspi->dma_tx_chnum = dma_tx_chan;
-
-               ret = davinci_spi_request_dma(dspi);
-               if (ret)
-                       goto free_clk;
-
-               dev_info(&pdev->dev, "DMA: supported\n");
-               dev_info(&pdev->dev, "DMA: RX channel: %pa, TX channel: %pa, event queue: %d\n",
-                               &dma_rx_chan, &dma_tx_chan,
-                               pdata->dma_event_q);
+
+       ret = davinci_spi_request_dma(dspi);
+       if (ret == -EPROBE_DEFER) {
+               goto free_clk;
+       } else if (ret) {
+               dev_info(&pdev->dev, "DMA is not supported (%d)\n", ret);
+               dspi->dma_rx = NULL;
+               dspi->dma_tx = NULL;
        }
 
        dspi->get_rx = davinci_spi_rx_buf_u8;
@@ -1102,8 +1067,10 @@ static int davinci_spi_probe(struct platform_device *pdev)
        return ret;
 
 free_dma:
-       dma_release_channel(dspi->dma_rx);
-       dma_release_channel(dspi->dma_tx);
+       if (dspi->dma_rx) {
+               dma_release_channel(dspi->dma_rx);
+               dma_release_channel(dspi->dma_tx);
+       }
 free_clk:
        clk_disable_unprepare(dspi->clk);
 free_master:
@@ -1134,6 +1101,11 @@ static int davinci_spi_remove(struct platform_device *pdev)
        clk_disable_unprepare(dspi->clk);
        spi_master_put(master);
 
+       if (dspi->dma_rx) {
+               dma_release_channel(dspi->dma_rx);
+               dma_release_channel(dspi->dma_tx);
+       }
+
        return 0;
 }