xref: /linux/drivers/hwtracing/coresight/coresight-replicator.c (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1 /* Copyright (c) 2011-2012, The Linux Foundation. All rights reserved.
2  *
3  * Description: CoreSight Replicator driver
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 and
7  * only version 2 as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/device.h>
17 #include <linux/platform_device.h>
18 #include <linux/io.h>
19 #include <linux/err.h>
20 #include <linux/slab.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/clk.h>
23 #include <linux/of.h>
24 #include <linux/coresight.h>
25 
26 #include "coresight-priv.h"
27 
28 /**
29  * struct replicator_drvdata - specifics associated to a replicator component
30  * @dev:	the device entity associated with this component
31  * @atclk:	optional clock for the core parts of the replicator.
32  * @csdev:	component vitals needed by the framework
33  */
34 struct replicator_drvdata {
35 	struct device		*dev;
36 	struct clk		*atclk;
37 	struct coresight_device	*csdev;
38 };
39 
40 static int replicator_enable(struct coresight_device *csdev, int inport,
41 			     int outport)
42 {
43 	struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
44 
45 	dev_info(drvdata->dev, "REPLICATOR enabled\n");
46 	return 0;
47 }
48 
49 static void replicator_disable(struct coresight_device *csdev, int inport,
50 			       int outport)
51 {
52 	struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
53 
54 	dev_info(drvdata->dev, "REPLICATOR disabled\n");
55 }
56 
57 static const struct coresight_ops_link replicator_link_ops = {
58 	.enable		= replicator_enable,
59 	.disable	= replicator_disable,
60 };
61 
62 static const struct coresight_ops replicator_cs_ops = {
63 	.link_ops	= &replicator_link_ops,
64 };
65 
66 static int replicator_probe(struct platform_device *pdev)
67 {
68 	int ret;
69 	struct device *dev = &pdev->dev;
70 	struct coresight_platform_data *pdata = NULL;
71 	struct replicator_drvdata *drvdata;
72 	struct coresight_desc desc = { 0 };
73 	struct device_node *np = pdev->dev.of_node;
74 
75 	if (np) {
76 		pdata = of_get_coresight_platform_data(dev, np);
77 		if (IS_ERR(pdata))
78 			return PTR_ERR(pdata);
79 		pdev->dev.platform_data = pdata;
80 	}
81 
82 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
83 	if (!drvdata)
84 		return -ENOMEM;
85 
86 	drvdata->dev = &pdev->dev;
87 	drvdata->atclk = devm_clk_get(&pdev->dev, "atclk"); /* optional */
88 	if (!IS_ERR(drvdata->atclk)) {
89 		ret = clk_prepare_enable(drvdata->atclk);
90 		if (ret)
91 			return ret;
92 	}
93 	pm_runtime_get_noresume(&pdev->dev);
94 	pm_runtime_set_active(&pdev->dev);
95 	pm_runtime_enable(&pdev->dev);
96 	platform_set_drvdata(pdev, drvdata);
97 
98 	desc.type = CORESIGHT_DEV_TYPE_LINK;
99 	desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_SPLIT;
100 	desc.ops = &replicator_cs_ops;
101 	desc.pdata = pdev->dev.platform_data;
102 	desc.dev = &pdev->dev;
103 	drvdata->csdev = coresight_register(&desc);
104 	if (IS_ERR(drvdata->csdev)) {
105 		ret = PTR_ERR(drvdata->csdev);
106 		goto out_disable_pm;
107 	}
108 
109 	pm_runtime_put(&pdev->dev);
110 
111 	return 0;
112 
113 out_disable_pm:
114 	if (!IS_ERR(drvdata->atclk))
115 		clk_disable_unprepare(drvdata->atclk);
116 	pm_runtime_put_noidle(&pdev->dev);
117 	pm_runtime_disable(&pdev->dev);
118 
119 	return ret;
120 }
121 
122 #ifdef CONFIG_PM
123 static int replicator_runtime_suspend(struct device *dev)
124 {
125 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
126 
127 	if (drvdata && !IS_ERR(drvdata->atclk))
128 		clk_disable_unprepare(drvdata->atclk);
129 
130 	return 0;
131 }
132 
133 static int replicator_runtime_resume(struct device *dev)
134 {
135 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
136 
137 	if (drvdata && !IS_ERR(drvdata->atclk))
138 		clk_prepare_enable(drvdata->atclk);
139 
140 	return 0;
141 }
142 #endif
143 
144 static const struct dev_pm_ops replicator_dev_pm_ops = {
145 	SET_RUNTIME_PM_OPS(replicator_runtime_suspend,
146 			   replicator_runtime_resume, NULL)
147 };
148 
149 static const struct of_device_id replicator_match[] = {
150 	{.compatible = "arm,coresight-replicator"},
151 	{}
152 };
153 
154 static struct platform_driver replicator_driver = {
155 	.probe          = replicator_probe,
156 	.driver         = {
157 		.name   = "coresight-replicator",
158 		.of_match_table = replicator_match,
159 		.pm	= &replicator_dev_pm_ops,
160 		.suppress_bind_attrs = true,
161 	},
162 };
163 builtin_platform_driver(replicator_driver);
164