xref: /linux/drivers/hwtracing/coresight/coresight-replicator.c (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
1 /* Copyright (c) 2011-2012, The Linux Foundation. All rights reserved.
2  *
3  * This program is free software; you can redistribute it and/or modify
4  * it under the terms of the GNU General Public License version 2 and
5  * only version 2 as published by the Free Software Foundation.
6  *
7  * This program is distributed in the hope that it will be useful,
8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  * GNU General Public License for more details.
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/device.h>
16 #include <linux/platform_device.h>
17 #include <linux/io.h>
18 #include <linux/err.h>
19 #include <linux/slab.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/clk.h>
22 #include <linux/of.h>
23 #include <linux/coresight.h>
24 
25 #include "coresight-priv.h"
26 
27 /**
28  * struct replicator_drvdata - specifics associated to a replicator component
29  * @dev:	the device entity associated with this component
30  * @atclk:	optional clock for the core parts of the replicator.
31  * @csdev:	component vitals needed by the framework
32  */
33 struct replicator_drvdata {
34 	struct device		*dev;
35 	struct clk		*atclk;
36 	struct coresight_device	*csdev;
37 };
38 
39 static int replicator_enable(struct coresight_device *csdev, int inport,
40 			     int outport)
41 {
42 	struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
43 
44 	pm_runtime_get_sync(drvdata->dev);
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 	pm_runtime_put(drvdata->dev);
55 	dev_info(drvdata->dev, "REPLICATOR disabled\n");
56 }
57 
58 static const struct coresight_ops_link replicator_link_ops = {
59 	.enable		= replicator_enable,
60 	.disable	= replicator_disable,
61 };
62 
63 static const struct coresight_ops replicator_cs_ops = {
64 	.link_ops	= &replicator_link_ops,
65 };
66 
67 static int replicator_probe(struct platform_device *pdev)
68 {
69 	int ret;
70 	struct device *dev = &pdev->dev;
71 	struct coresight_platform_data *pdata = NULL;
72 	struct replicator_drvdata *drvdata;
73 	struct coresight_desc *desc;
74 	struct device_node *np = pdev->dev.of_node;
75 
76 	if (np) {
77 		pdata = of_get_coresight_platform_data(dev, np);
78 		if (IS_ERR(pdata))
79 			return PTR_ERR(pdata);
80 		pdev->dev.platform_data = pdata;
81 	}
82 
83 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
84 	if (!drvdata)
85 		return -ENOMEM;
86 
87 	drvdata->dev = &pdev->dev;
88 	drvdata->atclk = devm_clk_get(&pdev->dev, "atclk"); /* optional */
89 	if (!IS_ERR(drvdata->atclk)) {
90 		ret = clk_prepare_enable(drvdata->atclk);
91 		if (ret)
92 			return ret;
93 	}
94 	pm_runtime_get_noresume(&pdev->dev);
95 	pm_runtime_set_active(&pdev->dev);
96 	pm_runtime_enable(&pdev->dev);
97 	platform_set_drvdata(pdev, drvdata);
98 
99 	desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
100 	if (!desc) {
101 		ret = -ENOMEM;
102 		goto out_disable_pm;
103 	}
104 
105 	desc->type = CORESIGHT_DEV_TYPE_LINK;
106 	desc->subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_SPLIT;
107 	desc->ops = &replicator_cs_ops;
108 	desc->pdata = pdev->dev.platform_data;
109 	desc->dev = &pdev->dev;
110 	drvdata->csdev = coresight_register(desc);
111 	if (IS_ERR(drvdata->csdev)) {
112 		ret = PTR_ERR(drvdata->csdev);
113 		goto out_disable_pm;
114 	}
115 
116 	pm_runtime_put(&pdev->dev);
117 
118 	dev_info(dev, "REPLICATOR initialized\n");
119 	return 0;
120 
121 out_disable_pm:
122 	if (!IS_ERR(drvdata->atclk))
123 		clk_disable_unprepare(drvdata->atclk);
124 	pm_runtime_put_noidle(&pdev->dev);
125 	pm_runtime_disable(&pdev->dev);
126 
127 	return ret;
128 }
129 
130 static int replicator_remove(struct platform_device *pdev)
131 {
132 	struct replicator_drvdata *drvdata = platform_get_drvdata(pdev);
133 
134 	coresight_unregister(drvdata->csdev);
135 	pm_runtime_get_sync(&pdev->dev);
136 	if (!IS_ERR(drvdata->atclk))
137 		clk_disable_unprepare(drvdata->atclk);
138 	pm_runtime_put_noidle(&pdev->dev);
139 	pm_runtime_disable(&pdev->dev);
140 
141 	return 0;
142 }
143 
144 #ifdef CONFIG_PM
145 static int replicator_runtime_suspend(struct device *dev)
146 {
147 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
148 
149 	if (drvdata && !IS_ERR(drvdata->atclk))
150 		clk_disable_unprepare(drvdata->atclk);
151 
152 	return 0;
153 }
154 
155 static int replicator_runtime_resume(struct device *dev)
156 {
157 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
158 
159 	if (drvdata && !IS_ERR(drvdata->atclk))
160 		clk_prepare_enable(drvdata->atclk);
161 
162 	return 0;
163 }
164 #endif
165 
166 static const struct dev_pm_ops replicator_dev_pm_ops = {
167 	SET_RUNTIME_PM_OPS(replicator_runtime_suspend,
168 			   replicator_runtime_resume, NULL)
169 };
170 
171 static const struct of_device_id replicator_match[] = {
172 	{.compatible = "arm,coresight-replicator"},
173 	{}
174 };
175 
176 static struct platform_driver replicator_driver = {
177 	.probe          = replicator_probe,
178 	.remove         = replicator_remove,
179 	.driver         = {
180 		.name   = "coresight-replicator",
181 		.of_match_table = replicator_match,
182 		.pm	= &replicator_dev_pm_ops,
183 	},
184 };
185 
186 builtin_platform_driver(replicator_driver);
187 
188 MODULE_LICENSE("GPL v2");
189 MODULE_DESCRIPTION("CoreSight Replicator driver");
190