[PATCH v5 2/3] serial: fsl_lpuart: add DMA support
From: mark.rutland@arm.com (Mark Rutland)
Date: 2014-02-14 10:24:15
Also in:
linux-serial
On Fri, Feb 14, 2014 at 07:27:18AM +0000, Yuan Yao wrote:
quoted hunk ↗ jump to hunk
Add dma support for lpuart. This function depend on DMA driver. You can turn on it by write both the dmas and dma-name properties in dts node. Signed-off-by: Yuan Yao <redacted> --- .../devicetree/bindings/serial/fsl-lpuart.txt | 19 +- drivers/tty/serial/fsl_lpuart.c | 430 ++++++++++++++++++++- 2 files changed, 433 insertions(+), 16 deletions(-)diff --git a/Documentation/devicetree/bindings/serial/fsl-lpuart.txt b/Documentation/devicetree/bindings/serial/fsl-lpuart.txt index 6fd1dd1..6e1cbbf 100644 --- a/Documentation/devicetree/bindings/serial/fsl-lpuart.txt +++ b/Documentation/devicetree/bindings/serial/fsl-lpuart.txt@@ -5,10 +5,24 @@ Required properties: - reg : Address and length of the register set for the device - interrupts : Should contain uart interrupt +Optional properties: +- dmas: List of two DMA specifiers, using a three-cell specifier for each channel. + a phandle plus two integer cells. The three cells in order are: + 1.A phandle pointing to the DMA controller. + 2.specifies the channel group(DMAMUX) in which this request can be multiplexed, + 3.specifies the request source.
The precise format of a dma-specifier is up to the DMA binding. Why does the client binding care?
+- dma-names: Contains one identifier string for each DMA specifier in the dmas property. + "tx" for the transmit channel, "rx" for the receive channel. + +Note: Optional properties for DMA support. Write them both or both not. +
All you need is something like: dmas: A list of two dma specifiers, one for each entry in dma-names dma-names: should contain "tx" and "rx". Thanks, Mark.