pch_uart: don't hardcode PCI slot to get DMA device

The DMA is a function 0 of the multifunction device where SPI host is attached.
Thus, we may avoid to hardcode PCI slot number.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index 2f06e5a71396..ea4ffc2ebb2f 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -736,9 +736,10 @@ static void pch_request_dma(struct uart_port *port)
         dma_cap_zero(mask);
         dma_cap_set(DMA_SLAVE, mask);
 
-        dma_dev = pci_get_bus_and_slot(priv->pdev->bus->number,
-                                       PCI_DEVFN(0xa, 0)); /* Get DMA's dev
-                                                                information */
+        /* Get DMA's dev information */
+        dma_dev = pci_get_slot(priv->pdev->bus,
+                        PCI_DEVFN(PCI_SLOT(priv->pdev->devfn), 0));
+
         /* Set Tx DMA */
         param = &priv->param_tx;
         param->dma_dev = &dma_dev->dev;