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 */
 34struct replicator_drvdata {
 35	struct device		*dev;
 36	struct clk		*atclk;
 37	struct coresight_device	*csdev;
 38};
 39
 40static 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
 49static 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
 57static const struct coresight_ops_link replicator_link_ops = {
 58	.enable		= replicator_enable,
 59	.disable	= replicator_disable,
 60};
 61
 62static const struct coresight_ops replicator_cs_ops = {
 63	.link_ops	= &replicator_link_ops,
 64};
 65
 66static 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;
 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 = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
 99	if (!desc) {
100		ret = -ENOMEM;
101		goto out_disable_pm;
102	}
103
104	desc->type = CORESIGHT_DEV_TYPE_LINK;
105	desc->subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_SPLIT;
106	desc->ops = &replicator_cs_ops;
107	desc->pdata = pdev->dev.platform_data;
108	desc->dev = &pdev->dev;
109	drvdata->csdev = coresight_register(desc);
110	if (IS_ERR(drvdata->csdev)) {
111		ret = PTR_ERR(drvdata->csdev);
112		goto out_disable_pm;
113	}
114
115	pm_runtime_put(&pdev->dev);
116
117	dev_info(dev, "REPLICATOR initialized\n");
118	return 0;
119
120out_disable_pm:
121	if (!IS_ERR(drvdata->atclk))
122		clk_disable_unprepare(drvdata->atclk);
123	pm_runtime_put_noidle(&pdev->dev);
124	pm_runtime_disable(&pdev->dev);
125
126	return ret;
127}
128
129#ifdef CONFIG_PM
130static int replicator_runtime_suspend(struct device *dev)
131{
132	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
133
134	if (drvdata && !IS_ERR(drvdata->atclk))
135		clk_disable_unprepare(drvdata->atclk);
136
137	return 0;
138}
139
140static int replicator_runtime_resume(struct device *dev)
141{
142	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
143
144	if (drvdata && !IS_ERR(drvdata->atclk))
145		clk_prepare_enable(drvdata->atclk);
146
147	return 0;
148}
149#endif
150
151static const struct dev_pm_ops replicator_dev_pm_ops = {
152	SET_RUNTIME_PM_OPS(replicator_runtime_suspend,
153			   replicator_runtime_resume, NULL)
154};
155
156static const struct of_device_id replicator_match[] = {
157	{.compatible = "arm,coresight-replicator"},
158	{}
159};
160
161static struct platform_driver replicator_driver = {
162	.probe          = replicator_probe,
163	.driver         = {
164		.name   = "coresight-replicator",
165		.of_match_table = replicator_match,
166		.pm	= &replicator_dev_pm_ops,
167		.suppress_bind_attrs = true,
168	},
169};
170builtin_platform_driver(replicator_driver);