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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
Merge tag 'tegra-for-4.8-bus' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux into next/drivers
bus: NVIDIA Tegra ACONNECT support
Adds support for the Tegra ACONNECT bus that's used to access the APE
(audio processing engine) on Tegra X1.
* tag 'tegra-for-4.8-bus' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux:
bus: Add support for Tegra ACONNECT
dt-bindings: bus: Add documentation for Tegra210 ACONNECT
Signed-off-by: Olof Johansson <olof@lixom.net>
+171
+45
Documentation/devicetree/bindings/bus/nvidia,tegra210-aconnect.txt
+45
Documentation/devicetree/bindings/bus/nvidia,tegra210-aconnect.txt
···
1
+
NVIDIA Tegra ACONNECT Bus
2
+
3
+
The Tegra ACONNECT bus is an AXI switch which is used to connnect various
4
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components inside the Audio Processing Engine (APE). All CPU accesses to
5
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the APE subsystem go through the ACONNECT via an APB to AXI wrapper.
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7
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Required properties:
8
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- compatible: Must be "nvidia,tegra210-aconnect".
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- clocks: Must contain the entries for the APE clock (TEGRA210_CLK_APE),
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and APE interface clock (TEGRA210_CLK_APB2APE).
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- clock-names: Must contain the names "ape" and "apb2ape" for the corresponding
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'clocks' entries.
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- power-domains: Must contain a phandle that points to the audio powergate
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(namely 'aud') for Tegra210.
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- #address-cells: The number of cells used to represent physical base addresses
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in the aconnect address space. Should be 1.
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- #size-cells: The number of cells used to represent the size of an address
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range in the aconnect address space. Should be 1.
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- ranges: Mapping of the aconnect address space to the CPU address space.
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All devices accessed via the ACONNNECT are described by child-nodes.
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Example:
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aconnect@702c0000 {
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compatible = "nvidia,tegra210-aconnect";
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clocks = <&tegra_car TEGRA210_CLK_APE>,
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<&tegra_car TEGRA210_CLK_APB2APE>;
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clock-names = "ape", "apb2ape";
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power-domains = <&pd_audio>;
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+
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#address-cells = <1>;
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#size-cells = <1>;
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ranges = <0x702c0000 0x0 0x702c0000 0x00040000>;
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+
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status = "disabled";
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+
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child1 {
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...
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};
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child2 {
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...
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};
45
+
};
+13
drivers/bus/Kconfig
+13
drivers/bus/Kconfig
···
132
132
with various RSB based devices, such as AXP223, AXP8XX PMICs,
133
133
and AC100/AC200 ICs.
134
134
135
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# TODO: This uses pm_clk_*() symbols that aren't exported in v4.7 and hence
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# the driver will fail to build as a module. However there are patches to
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# address that queued for v4.8, so this can be turned into a tristate symbol
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# after v4.8-rc1.
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config TEGRA_ACONNECT
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bool "Tegra ACONNECT Bus Driver"
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depends on ARCH_TEGRA_210_SOC
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depends on OF && PM
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select PM_CLK
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help
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Driver for the Tegra ACONNECT bus which is used to interface with
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the devices inside the Audio Processing Engine (APE) for Tegra210.
147
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135
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config UNIPHIER_SYSTEM_BUS
136
149
tristate "UniPhier System Bus driver"
137
150
depends on ARCH_UNIPHIER && OF
+1
drivers/bus/Makefile
+1
drivers/bus/Makefile
···
17
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obj-$(CONFIG_OMAP_OCP2SCP) += omap-ocp2scp.o
18
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obj-$(CONFIG_SUNXI_RSB) += sunxi-rsb.o
19
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obj-$(CONFIG_SIMPLE_PM_BUS) += simple-pm-bus.o
20
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obj-$(CONFIG_TEGRA_ACONNECT) += tegra-aconnect.o
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obj-$(CONFIG_UNIPHIER_SYSTEM_BUS) += uniphier-system-bus.o
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obj-$(CONFIG_VEXPRESS_CONFIG) += vexpress-config.o
+112
drivers/bus/tegra-aconnect.c
+112
drivers/bus/tegra-aconnect.c
···
1
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/*
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* Tegra ACONNECT Bus Driver
3
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*
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* Copyright (C) 2016, NVIDIA CORPORATION. All rights reserved.
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
8
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* for more details.
9
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*/
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#include <linux/clk.h>
12
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#include <linux/module.h>
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#include <linux/of_platform.h>
14
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#include <linux/platform_device.h>
15
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#include <linux/pm_clock.h>
16
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#include <linux/pm_runtime.h>
17
+
18
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static int tegra_aconnect_add_clock(struct device *dev, char *name)
19
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{
20
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struct clk *clk;
21
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int ret;
22
+
23
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clk = clk_get(dev, name);
24
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if (IS_ERR(clk)) {
25
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dev_err(dev, "%s clock not found\n", name);
26
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return PTR_ERR(clk);
27
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}
28
+
29
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ret = pm_clk_add_clk(dev, clk);
30
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if (ret)
31
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clk_put(clk);
32
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33
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return ret;
34
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}
35
+
36
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static int tegra_aconnect_probe(struct platform_device *pdev)
37
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{
38
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int ret;
39
+
40
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if (!pdev->dev.of_node)
41
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return -EINVAL;
42
+
43
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ret = pm_clk_create(&pdev->dev);
44
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if (ret)
45
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return ret;
46
+
47
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ret = tegra_aconnect_add_clock(&pdev->dev, "ape");
48
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if (ret)
49
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goto clk_destroy;
50
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51
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ret = tegra_aconnect_add_clock(&pdev->dev, "apb2ape");
52
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if (ret)
53
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goto clk_destroy;
54
+
55
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pm_runtime_enable(&pdev->dev);
56
+
57
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of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
58
+
59
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dev_info(&pdev->dev, "Tegra ACONNECT bus registered\n");
60
+
61
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return 0;
62
+
63
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clk_destroy:
64
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pm_clk_destroy(&pdev->dev);
65
+
66
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return ret;
67
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}
68
+
69
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static int tegra_aconnect_remove(struct platform_device *pdev)
70
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{
71
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pm_runtime_disable(&pdev->dev);
72
+
73
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pm_clk_destroy(&pdev->dev);
74
+
75
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return 0;
76
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}
77
+
78
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static int tegra_aconnect_runtime_resume(struct device *dev)
79
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{
80
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return pm_clk_resume(dev);
81
+
}
82
+
83
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static int tegra_aconnect_runtime_suspend(struct device *dev)
84
+
{
85
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return pm_clk_suspend(dev);
86
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}
87
+
88
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static const struct dev_pm_ops tegra_aconnect_pm_ops = {
89
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SET_RUNTIME_PM_OPS(tegra_aconnect_runtime_suspend,
90
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tegra_aconnect_runtime_resume, NULL)
91
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};
92
+
93
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static const struct of_device_id tegra_aconnect_of_match[] = {
94
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{ .compatible = "nvidia,tegra210-aconnect", },
95
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{ }
96
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};
97
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MODULE_DEVICE_TABLE(of, tegra_aconnect_of_match);
98
+
99
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static struct platform_driver tegra_aconnect_driver = {
100
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.probe = tegra_aconnect_probe,
101
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.remove = tegra_aconnect_remove,
102
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.driver = {
103
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.name = "tegra-aconnect",
104
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.of_match_table = tegra_aconnect_of_match,
105
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.pm = &tegra_aconnect_pm_ops,
106
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},
107
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};
108
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module_platform_driver(tegra_aconnect_driver);
109
+
110
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MODULE_DESCRIPTION("NVIDIA Tegra ACONNECT Bus Driver");
111
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MODULE_AUTHOR("Jon Hunter <jonathanh@nvidia.com>");
112
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MODULE_LICENSE("GPL v2");