drivers/hwtracing/coresight/coresight-replicator.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2011-2012, The Linux Foundation. All rights reserved.
   4  *
   5  * Description: CoreSight Replicator driver
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/device.h>
  10 #include <linux/platform_device.h>
  11 #include <linux/io.h>
  12 #include <linux/err.h>
  13 #include <linux/slab.h>
  14 #include <linux/pm_runtime.h>
  15 #include <linux/clk.h>
  16 #include <linux/of.h>
  17 #include <linux/coresight.h>
  18
  19 #include "coresight-priv.h"
  20
  21 /**
  22  * struct replicator_drvdata - specifics associated to a replicator component
  23  * @dev:        the device entity associated with this component
  24  * @atclk:      optional clock for the core parts of the replicator.
  25  * @csdev:      component vitals needed by the framework
  26  */
  27 struct replicator_drvdata {
  28         struct device           *dev;
  29         struct clk              *atclk;
  30         struct coresight_device *csdev;
  31 };
  32
  33 static int replicator_enable(struct coresight_device *csdev, int inport,
  34                              int outport)
  35 {
  36         struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
  37
  38         dev_info(drvdata->dev, "REPLICATOR enabled\n");
  39         return 0;
  40 }
  41
  42 static void replicator_disable(struct coresight_device *csdev, int inport,
  43                                int outport)
  44 {
  45         struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
  46
  47         dev_info(drvdata->dev, "REPLICATOR disabled\n");
  48 }
  49
  50 static const struct coresight_ops_link replicator_link_ops = {
  51         .enable         = replicator_enable,
  52         .disable        = replicator_disable,
  53 };
  54
  55 static const struct coresight_ops replicator_cs_ops = {
  56         .link_ops       = &replicator_link_ops,
  57 };
  58
  59 static int replicator_probe(struct platform_device *pdev)
  60 {
  61         int ret;
  62         struct device *dev = &pdev->dev;
  63         struct coresight_platform_data *pdata = NULL;
  64         struct replicator_drvdata *drvdata;
  65         struct coresight_desc desc = { 0 };
  66         struct device_node *np = pdev->dev.of_node;
  67
  68         if (np) {
  69                 pdata = of_get_coresight_platform_data(dev, np);
  70                 if (IS_ERR(pdata))
  71                         return PTR_ERR(pdata);
  72                 pdev->dev.platform_data = pdata;
  73         }
  74
  75         drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
  76         if (!drvdata)
  77                 return -ENOMEM;
  78
  79         drvdata->dev = &pdev->dev;
  80         drvdata->atclk = devm_clk_get(&pdev->dev, "atclk"); /* optional */
  81         if (!IS_ERR(drvdata->atclk)) {
  82                 ret = clk_prepare_enable(drvdata->atclk);
  83                 if (ret)
  84                         return ret;
  85         }
  86         pm_runtime_get_noresume(&pdev->dev);
  87         pm_runtime_set_active(&pdev->dev);
  88         pm_runtime_enable(&pdev->dev);
  89         platform_set_drvdata(pdev, drvdata);
  90
  91         desc.type = CORESIGHT_DEV_TYPE_LINK;
  92         desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_SPLIT;
  93         desc.ops = &replicator_cs_ops;
  94         desc.pdata = pdev->dev.platform_data;
  95         desc.dev = &pdev->dev;
  96         drvdata->csdev = coresight_register(&desc);
  97         if (IS_ERR(drvdata->csdev)) {
  98                 ret = PTR_ERR(drvdata->csdev);
  99                 goto out_disable_pm;
 100         }
 101
 102         pm_runtime_put(&pdev->dev);
 103
 104         return 0;
 105
 106 out_disable_pm:
 107         if (!IS_ERR(drvdata->atclk))
 108                 clk_disable_unprepare(drvdata->atclk);
 109         pm_runtime_put_noidle(&pdev->dev);
 110         pm_runtime_disable(&pdev->dev);
 111
 112         return ret;
 113 }
 114
 115 #ifdef CONFIG_PM
 116 static int replicator_runtime_suspend(struct device *dev)
 117 {
 118         struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
 119
 120         if (drvdata && !IS_ERR(drvdata->atclk))
 121                 clk_disable_unprepare(drvdata->atclk);
 122
 123         return 0;
 124 }
 125
 126 static int replicator_runtime_resume(struct device *dev)
 127 {
 128         struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
 129
 130         if (drvdata && !IS_ERR(drvdata->atclk))
 131                 clk_prepare_enable(drvdata->atclk);
 132
 133         return 0;
 134 }
 135 #endif
 136
 137 static const struct dev_pm_ops replicator_dev_pm_ops = {
 138         SET_RUNTIME_PM_OPS(replicator_runtime_suspend,
 139                            replicator_runtime_resume, NULL)
 140 };
 141
 142 static const struct of_device_id replicator_match[] = {
 143         {.compatible = "arm,coresight-replicator"},
 144         {}
 145 };
 146
 147 static struct platform_driver replicator_driver = {
 148         .probe          = replicator_probe,
 149         .driver         = {
 150                 .name   = "coresight-replicator",
 151                 .of_match_table = replicator_match,
 152                 .pm     = &replicator_dev_pm_ops,
 153                 .suppress_bind_attrs = true,
 154         },
 155 };
 156 builtin_platform_driver(replicator_driver);