Merge tag 'tty-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here's the tty and serial driver patches for 4.2-rc1.

  A number of individual driver updates, some code cleanups, and other
  minor things, full details in the shortlog.

  All have been in linux-next for a while with no reported issues"

* tag 'tty-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (152 commits)
  Doc: serial-rs485.txt: update RS485 driver interface
  Doc: tty.txt: remove mention of the BKL
  MAINTAINERS: tty: add serial docs directory
  serial: sprd: check for NULL after calling devm_clk_get
  serial: 8250_pci: Correct uartclk for xr17v35x expansion chips
  serial: 8250_pci: Add support for 12 port Exar boards
  serial: 8250_uniphier: add bindings document for UniPhier UART
  serial: core: cleanup in uart_get_baud_rate()
  serial: stm32-usart: Add STM32 USART Driver
  tty/serial: kill off set_irq_flags usage
  tty: move linux/gsmmux.h to uapi
  doc: dt: add documentation for nxp,lpc1850-uart
  serial: 8250: add LPC18xx/43xx UART driver
  serial: 8250_uniphier: add UniPhier serial driver
  serial: 8250_dw: support ACPI platforms with integrated DMA engine
  serial: of_serial: check the return value of clk_prepare_enable()
  serial: of_serial: use devm_clk_get() instead of clk_get()
  serial: earlycon: Add support for big-endian MMIO accesses
  serial: sirf: use hrtimer for data rx
  serial: sirf: correct the fifo empty_bit
  ...

1 files changed, 18 insertions, 1 deletions

diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 176f18f2e3ab..d48b50641e9a 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -377,6 +377,16 @@ static int dw8250_probe_of(struct uart_port *p,
 	return 0;
 }
 
+static bool dw8250_idma_filter(struct dma_chan *chan, void *param)
+{
+	struct device *dev = param;
+
+	if (dev != chan->device->dev->parent)
+		return false;
+
+	return true;
+}
+
 static int dw8250_probe_acpi(struct uart_8250_port *up,
 			     struct dw8250_data *data)
 {
@@ -389,8 +399,15 @@ static int dw8250_probe_acpi(struct uart_8250_port *up,
 	p->serial_out = dw8250_serial_out32;
 	p->regshift = 2;
 
-	up->dma = &data->dma;
+	/* Platforms with iDMA */
+	if (platform_get_resource_byname(to_platform_device(up->port.dev),
+					 IORESOURCE_MEM, "lpss_priv")) {
+		data->dma.rx_param = up->port.dev->parent;
+		data->dma.tx_param = up->port.dev->parent;
+		data->dma.fn = dw8250_idma_filter;
+	}
 
+	up->dma = &data->dma;
 	up->dma->rxconf.src_maxburst = p->fifosize / 4;
 	up->dma->txconf.dst_maxburst = p->fifosize / 4;