drivers/bus/omap-ocp2scp.c

   1 /*
   2  * omap-ocp2scp.c - transform ocp interface protocol to scp protocol
   3  *
   4  * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * Author: Kishon Vijay Abraham I <kishon@ti.com>
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/err.h>
  22 #include <linux/pm_runtime.h>
  23 #include <linux/of.h>
  24 #include <linux/of_platform.h>
  25 #include <linux/platform_data/omap_ocp2scp.h>
  26
  27 /**
  28  * _count_resources - count for the number of resources
  29  * @res: struct resource *
  30  *
  31  * Count and return the number of resources populated for the device that is
  32  * connected to ocp2scp.
  33  */
  34 static unsigned _count_resources(struct resource *res)
  35 {
  36         int cnt = 0;
  37
  38         while (res->start != res->end) {
  39                 cnt++;
  40                 res++;
  41         }
  42
  43         return cnt;
  44 }
  45
  46 static int ocp2scp_remove_devices(struct device *dev, void *c)
  47 {
  48         struct platform_device *pdev = to_platform_device(dev);
  49
  50         platform_device_unregister(pdev);
  51
  52         return 0;
  53 }
  54
  55 static int omap_ocp2scp_probe(struct platform_device *pdev)
  56 {
  57         int ret;
  58         unsigned res_cnt, i;
  59         struct device_node *np = pdev->dev.of_node;
  60         struct platform_device *pdev_child;
  61         struct omap_ocp2scp_platform_data *pdata = pdev->dev.platform_data;
  62         struct omap_ocp2scp_dev *dev;
  63
  64         if (np) {
  65                 ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
  66                 if (ret) {
  67                         dev_err(&pdev->dev,
  68                             "failed to add resources for ocp2scp child\n");
  69                         goto err0;
  70                 }
  71         } else if (pdata) {
  72                 for (i = 0, dev = *pdata->devices; i < pdata->dev_cnt; i++,
  73                     dev++) {
  74                         res_cnt = _count_resources(dev->res);
  75
  76                         pdev_child = platform_device_alloc(dev->drv_name,
  77                             PLATFORM_DEVID_AUTO);
  78                         if (!pdev_child) {
  79                                 dev_err(&pdev->dev,
  80                                   "failed to allocate mem for ocp2scp child\n");
  81                                 goto err0;
  82                         }
  83
  84                         ret = platform_device_add_resources(pdev_child,
  85                             dev->res, res_cnt);
  86                         if (ret) {
  87                                 dev_err(&pdev->dev,
  88                                  "failed to add resources for ocp2scp child\n");
  89                                 goto err1;
  90                         }
  91
  92                         pdev_child->dev.parent  = &pdev->dev;
  93
  94                         ret = platform_device_add(pdev_child);
  95                         if (ret) {
  96                                 dev_err(&pdev->dev,
  97                                    "failed to register ocp2scp child device\n");
  98                                 goto err1;
  99                         }
 100                 }
 101         } else {
 102                 dev_err(&pdev->dev, "OCP2SCP initialized without plat data\n");
 103                 return -EINVAL;
 104         }
 105
 106         pm_runtime_enable(&pdev->dev);
 107
 108         return 0;
 109
 110 err1:
 111         platform_device_put(pdev_child);
 112
 113 err0:
 114         device_for_each_child(&pdev->dev, NULL, ocp2scp_remove_devices);
 115
 116         return ret;
 117 }
 118
 119 static int omap_ocp2scp_remove(struct platform_device *pdev)
 120 {
 121         pm_runtime_disable(&pdev->dev);
 122         device_for_each_child(&pdev->dev, NULL, ocp2scp_remove_devices);
 123
 124         return 0;
 125 }
 126
 127 #ifdef CONFIG_OF
 128 static const struct of_device_id omap_ocp2scp_id_table[] = {
 129         { .compatible = "ti,omap-ocp2scp" },
 130         {}
 131 };
 132 MODULE_DEVICE_TABLE(of, omap_ocp2scp_id_table);
 133 #endif
 134
 135 static struct platform_driver omap_ocp2scp_driver = {
 136         .probe          = omap_ocp2scp_probe,
 137         .remove         = omap_ocp2scp_remove,
 138         .driver         = {
 139                 .name   = "omap-ocp2scp",
 140                 .owner  = THIS_MODULE,
 141                 .of_match_table = of_match_ptr(omap_ocp2scp_id_table),
 142         },
 143 };
 144
 145 module_platform_driver(omap_ocp2scp_driver);
 146
 147 MODULE_ALIAS("platform: omap-ocp2scp");
 148 MODULE_AUTHOR("Texas Instruments Inc.");
 149 MODULE_DESCRIPTION("OMAP OCP2SCP driver");
 150 MODULE_LICENSE("GPL v2");