dmaengine: idma64: Use actual device for DMA transfers

Intel IOMMU, when enabled, tries to find the domain of the device,
assuming it's a PCI one, during DMA operations, such as mapping or
unmapping. Since we are splitting the actual PCI device to couple of
children via MFD framework (see drivers/mfd/intel-lpss.c for details),
the DMA device appears to be a platform one, and thus not an actual one
that performs DMA. In a such situation IOMMU can't find or allocate
a proper domain for its operations. As a result, all DMA operations are
failed.

In order to fix this, supply parent of the platform device
to the DMA engine framework and fix filter functions accordingly.

We may rely on the fact that parent is a real PCI device, because no
other configuration is present in the wild.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [for tty parts]
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/dma/idma64.c b/drivers/dma/idma64.c
index 0baf9797cc09d708a5365bef68f9bdf75a079f29..83796a33dc1693008d8f33d9404cd6bd81d9e8af 100644 (file)
--- a/drivers/dma/idma64.c
+++ b/drivers/dma/idma64.c
@@ -592,7 +592,7 @@ static int idma64_probe(struct idma64_chip *chip)
        idma64->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
        idma64->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
 
-       idma64->dma.dev = chip->dev;
+       idma64->dma.dev = chip->sysdev;
 
        dma_set_max_seg_size(idma64->dma.dev, IDMA64C_CTLH_BLOCK_TS_MASK);
 
@@ -632,6 +632,7 @@ static int idma64_platform_probe(struct platform_device *pdev)
 {
        struct idma64_chip *chip;
        struct device *dev = &pdev->dev;
+       struct device *sysdev = dev->parent;
        struct resource *mem;
        int ret;
 
@@ -648,11 +649,12 @@ static int idma64_platform_probe(struct platform_device *pdev)
        if (IS_ERR(chip->regs))
                return PTR_ERR(chip->regs);
 
-       ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+       ret = dma_coerce_mask_and_coherent(sysdev, DMA_BIT_MASK(64));
        if (ret)
                return ret;
 
        chip->dev = dev;
+       chip->sysdev = sysdev;
 
        ret = idma64_probe(chip);
        if (ret)

diff --git a/drivers/dma/idma64.h b/drivers/dma/idma64.h
index 6b816878e5e7a79d9e4fb14f982e3aa21e3e34a2..baa32e1425de31dcfbf88f8ea10d0002a5fe3e13 100644 (file)
--- a/drivers/dma/idma64.h
+++ b/drivers/dma/idma64.h
@@ -216,12 +216,14 @@ static inline void idma64_writel(struct idma64 *idma64, int offset, u32 value)
 /**
  * struct idma64_chip - representation of iDMA 64-bit controller hardware
  * @dev:               struct device of the DMA controller
+ * @sysdev:            struct device of the physical device that does DMA
  * @irq:               irq line
  * @regs:              memory mapped I/O space
  * @idma64:            struct idma64 that is filed by idma64_probe()
  */
 struct idma64_chip {
        struct device   *dev;
+       struct device   *sysdev;
        int             irq;
        void __iomem    *regs;
        struct idma64   *idma64;

diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index b6ddba833d021968858d22bd8cb6a7b55c08993e..5ea70f7d12e757b4d4f517076c770116affa04d7 100644 (file)
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -1487,12 +1487,7 @@ static int pxa2xx_spi_get_port_id(struct acpi_device *adev)
 
 static bool pxa2xx_spi_idma_filter(struct dma_chan *chan, void *param)
 {
-       struct device *dev = param;
-
-       if (dev != chan->device->dev->parent)
-               return false;
-
-       return true;
+       return param == chan->device->dev;
 }
 
 #endif /* CONFIG_PCI */

diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index d31b975dd3fd7b7c4ac052390bca7884b2bff468..284e8d052fc3ced300ec73f5bf5945ea45d2aaf1 100644 (file)
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -365,7 +365,7 @@ static bool dw8250_fallback_dma_filter(struct dma_chan *chan, void *param)
 
 static bool dw8250_idma_filter(struct dma_chan *chan, void *param)
 {
-       return param == chan->device->dev->parent;
+       return param == chan->device->dev;
 }
 
 /*
@@ -434,7 +434,7 @@ static void dw8250_quirks(struct uart_port *p, struct dw8250_data *data)
                data->uart_16550_compatible = true;
        }
 
-       /* Platforms with iDMA */
+       /* Platforms with iDMA 64-bit */
        if (platform_get_resource_byname(to_platform_device(p->dev),
                                         IORESOURCE_MEM, "lpss_priv")) {
                data->dma.rx_param = p->dev->parent;