LXR linux/drivers/hwtracing/coresight/coresight-replicator.c

   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 = { 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
 113out_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
 123static 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
 133static 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
 144static const struct dev_pm_ops replicator_dev_pm_ops = {
 145        SET_RUNTIME_PM_OPS(replicator_runtime_suspend,
 146                           replicator_runtime_resume, NULL)
 147};
 148
 149static const struct of_device_id replicator_match[] = {
 150        {.compatible = "arm,coresight-replicator"},
 151        {}
 152};
 153
 154static 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};
 163builtin_platform_driver(replicator_driver);
 164