tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
dmaengine: add device tree binding documentation for the nbpfaxi driver
The nbpfaxi dmaengine driver doesn't define any new bindings, it only
uses standard dmaengine bindings and defines 3 flags for the 3rd parameter
of the "dmas" property.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
authored by
Guennadi Liakhovetski
and committed by
Vinod Koul
94c7b6fc
ed64610f
+81
+61
Documentation/devicetree/bindings/dma/nbpfaxi.txt
+61
Documentation/devicetree/bindings/dma/nbpfaxi.txt
···
1
+
* Renesas "Type-AXI" NBPFAXI* DMA controllers
2
+
3
+
* DMA controller
4
+
5
+
Required properties
6
+
7
+
- compatible: must be one of
8
+
"renesas,nbpfaxi64dmac1b4"
9
+
"renesas,nbpfaxi64dmac1b8"
10
+
"renesas,nbpfaxi64dmac1b16"
11
+
"renesas,nbpfaxi64dmac4b4"
12
+
"renesas,nbpfaxi64dmac4b8"
13
+
"renesas,nbpfaxi64dmac4b16"
14
+
"renesas,nbpfaxi64dmac8b4"
15
+
"renesas,nbpfaxi64dmac8b8"
16
+
"renesas,nbpfaxi64dmac8b16"
17
+
- #dma-cells: must be 2: the first integer is a terminal number, to which this
18
+
slave is connected, the second one is flags. Flags is a bitmask
19
+
with the following bits defined:
20
+
21
+
#define NBPF_SLAVE_RQ_HIGH 1
22
+
#define NBPF_SLAVE_RQ_LOW 2
23
+
#define NBPF_SLAVE_RQ_LEVEL 4
24
+
25
+
Optional properties:
26
+
27
+
You can use dma-channels and dma-requests as described in dma.txt, although they
28
+
won't be used, this information is derived from the compatibility string.
29
+
30
+
Example:
31
+
32
+
dma: dma-controller@48000000 {
33
+
compatible = "renesas,nbpfaxi64dmac8b4";
34
+
reg = <0x48000000 0x400>;
35
+
interrupts = <0 12 0x4
36
+
0 13 0x4
37
+
0 14 0x4
38
+
0 15 0x4
39
+
0 16 0x4
40
+
0 17 0x4
41
+
0 18 0x4
42
+
0 19 0x4>;
43
+
#dma-cells = <2>;
44
+
dma-channels = <8>;
45
+
dma-requests = <8>;
46
+
};
47
+
48
+
* DMA client
49
+
50
+
Required properties:
51
+
52
+
dmas and dma-names are required, as described in dma.txt.
53
+
54
+
Example:
55
+
56
+
#include <dt-bindings/dma/nbpfaxi.h>
57
+
58
+
...
59
+
dmas = <&dma 0 (NBPF_SLAVE_RQ_HIGH | NBPF_SLAVE_RQ_LEVEL)
60
+
&dma 1 (NBPF_SLAVE_RQ_HIGH | NBPF_SLAVE_RQ_LEVEL)>;
61
+
dma-names = "rx", "tx";
+20
include/dt-bindings/dma/nbpfaxi.h
+20
include/dt-bindings/dma/nbpfaxi.h
···
1
+
/*
2
+
* Copyright (C) 2013-2014 Renesas Electronics Europe Ltd.
3
+
* Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
4
+
*
5
+
* This program is free software; you can redistribute it and/or modify
6
+
* it under the terms of version 2 of the GNU General Public License as
7
+
* published by the Free Software Foundation.
8
+
*/
9
+
10
+
#ifndef DT_BINDINGS_NBPFAXI_H
11
+
#define DT_BINDINGS_NBPFAXI_H
12
+
13
+
/**
14
+
* Use "#dma-cells = <2>;" with the second integer defining slave DMA flags:
15
+
*/
16
+
#define NBPF_SLAVE_RQ_HIGH 1
17
+
#define NBPF_SLAVE_RQ_LOW 2
18
+
#define NBPF_SLAVE_RQ_LEVEL 4
19
+
20
+
#endif