drivers/hwtracing/coresight/coresight-replicator.c

   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/init.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         pm_runtime_get_sync(drvdata->dev);
  46         dev_info(drvdata->dev, "REPLICATOR enabled\n");
  47         return 0;
  48 }
  49
  50 static void replicator_disable(struct coresight_device *csdev, int inport,
  51                                int outport)
  52 {
  53         struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
  54
  55         pm_runtime_put(drvdata->dev);
  56         dev_info(drvdata->dev, "REPLICATOR disabled\n");
  57 }
  58
  59 static const struct coresight_ops_link replicator_link_ops = {
  60         .enable         = replicator_enable,
  61         .disable        = replicator_disable,
  62 };
  63
  64 static const struct coresight_ops replicator_cs_ops = {
  65         .link_ops       = &replicator_link_ops,
  66 };
  67
  68 static int replicator_probe(struct platform_device *pdev)
  69 {
  70         int ret;
  71         struct device *dev = &pdev->dev;
  72         struct coresight_platform_data *pdata = NULL;
  73         struct replicator_drvdata *drvdata;
  74         struct coresight_desc *desc;
  75         struct device_node *np = pdev->dev.of_node;
  76
  77         if (np) {
  78                 pdata = of_get_coresight_platform_data(dev, np);
  79                 if (IS_ERR(pdata))
  80                         return PTR_ERR(pdata);
  81                 pdev->dev.platform_data = pdata;
  82         }
  83
  84         drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
  85         if (!drvdata)
  86                 return -ENOMEM;
  87
  88         drvdata->dev = &pdev->dev;
  89         drvdata->atclk = devm_clk_get(&pdev->dev, "atclk"); /* optional */
  90         if (!IS_ERR(drvdata->atclk)) {
  91                 ret = clk_prepare_enable(drvdata->atclk);
  92                 if (ret)
  93                         return ret;
  94         }
  95         pm_runtime_get_noresume(&pdev->dev);
  96         pm_runtime_set_active(&pdev->dev);
  97         pm_runtime_enable(&pdev->dev);
  98         platform_set_drvdata(pdev, drvdata);
  99
 100         desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
 101         if (!desc) {
 102                 ret = -ENOMEM;
 103                 goto out_disable_pm;
 104         }
 105
 106         desc->type = CORESIGHT_DEV_TYPE_LINK;
 107         desc->subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_SPLIT;
 108         desc->ops = &replicator_cs_ops;
 109         desc->pdata = pdev->dev.platform_data;
 110         desc->dev = &pdev->dev;
 111         drvdata->csdev = coresight_register(desc);
 112         if (IS_ERR(drvdata->csdev)) {
 113                 ret = PTR_ERR(drvdata->csdev);
 114                 goto out_disable_pm;
 115         }
 116
 117         pm_runtime_put(&pdev->dev);
 118
 119         dev_info(dev, "REPLICATOR initialized\n");
 120         return 0;
 121
 122 out_disable_pm:
 123         if (!IS_ERR(drvdata->atclk))
 124                 clk_disable_unprepare(drvdata->atclk);
 125         pm_runtime_put_noidle(&pdev->dev);
 126         pm_runtime_disable(&pdev->dev);
 127
 128         return ret;
 129 }
 130
 131 static int replicator_remove(struct platform_device *pdev)
 132 {
 133         struct replicator_drvdata *drvdata = platform_get_drvdata(pdev);
 134
 135         coresight_unregister(drvdata->csdev);
 136         pm_runtime_get_sync(&pdev->dev);
 137         if (!IS_ERR(drvdata->atclk))
 138                 clk_disable_unprepare(drvdata->atclk);
 139         pm_runtime_put_noidle(&pdev->dev);
 140         pm_runtime_disable(&pdev->dev);
 141
 142         return 0;
 143 }
 144
 145 #ifdef CONFIG_PM
 146 static int replicator_runtime_suspend(struct device *dev)
 147 {
 148         struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
 149
 150         if (drvdata && !IS_ERR(drvdata->atclk))
 151                 clk_disable_unprepare(drvdata->atclk);
 152
 153         return 0;
 154 }
 155
 156 static int replicator_runtime_resume(struct device *dev)
 157 {
 158         struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
 159
 160         if (drvdata && !IS_ERR(drvdata->atclk))
 161                 clk_prepare_enable(drvdata->atclk);
 162
 163         return 0;
 164 }
 165 #endif
 166
 167 static const struct dev_pm_ops replicator_dev_pm_ops = {
 168         SET_RUNTIME_PM_OPS(replicator_runtime_suspend,
 169                            replicator_runtime_resume, NULL)
 170 };
 171
 172 static const struct of_device_id replicator_match[] = {
 173         {.compatible = "arm,coresight-replicator"},
 174         {}
 175 };
 176
 177 static struct platform_driver replicator_driver = {
 178         .probe          = replicator_probe,
 179         .remove         = replicator_remove,
 180         .driver         = {
 181                 .name   = "coresight-replicator",
 182                 .of_match_table = replicator_match,
 183                 .pm     = &replicator_dev_pm_ops,
 184         },
 185 };
 186
 187 static int __init replicator_init(void)
 188 {
 189         return platform_driver_register(&replicator_driver);
 190 }
 191 module_init(replicator_init);
 192
 193 static void __exit replicator_exit(void)
 194 {
 195         platform_driver_unregister(&replicator_driver);
 196 }
 197 module_exit(replicator_exit);
 198
 199 MODULE_LICENSE("GPL v2");
 200 MODULE_DESCRIPTION("CoreSight Replicator driver");