drivers/mcb/mcb-lpc.c

   1 /*
   2  * MEN Chameleon Bus.
   3  *
   4  * Copyright (C) 2014 MEN Mikroelektronik GmbH (www.men.de)
   5  * Author: Andreas Werner <[email protected]>
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the Free
   9  * Software Foundation; version 2 of the License.
  10  */
  11
  12 #include <linux/platform_device.h>
  13 #include <linux/module.h>
  14 #include <linux/dmi.h>
  15 #include <linux/mcb.h>
  16 #include <linux/io.h>
  17 #include "mcb-internal.h"
  18
  19 struct priv {
  20         struct mcb_bus *bus;
  21         struct resource *mem;
  22         void __iomem *base;
  23 };
  24
  25 static int mcb_lpc_probe(struct platform_device *pdev)
  26 {
  27         struct resource *res;
  28         struct priv *priv;
  29         int ret = 0;
  30
  31         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
  32         if (!priv)
  33                 return -ENOMEM;
  34
  35         priv->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  36         if (!priv->mem) {
  37                 dev_err(&pdev->dev, "No Memory resource\n");
  38                 return -ENODEV;
  39         }
  40
  41         res = devm_request_mem_region(&pdev->dev, priv->mem->start,
  42                                       resource_size(priv->mem),
  43                                       KBUILD_MODNAME);
  44         if (!res) {
  45                 dev_err(&pdev->dev, "Failed to request IO memory\n");
  46                 return -EBUSY;
  47         }
  48
  49         priv->base = devm_ioremap(&pdev->dev, priv->mem->start,
  50                                   resource_size(priv->mem));
  51         if (!priv->base) {
  52                 dev_err(&pdev->dev, "Cannot ioremap\n");
  53                 return -ENOMEM;
  54         }
  55
  56         platform_set_drvdata(pdev, priv);
  57
  58         priv->bus = mcb_alloc_bus(&pdev->dev);
  59         if (IS_ERR(priv->bus))
  60                 return PTR_ERR(priv->bus);
  61
  62         ret = chameleon_parse_cells(priv->bus, priv->mem->start, priv->base);
  63         if (ret < 0) {
  64                 mcb_release_bus(priv->bus);
  65                 return ret;
  66         }
  67
  68         dev_dbg(&pdev->dev, "Found %d cells\n", ret);
  69
  70         mcb_bus_add_devices(priv->bus);
  71
  72         return 0;
  73
  74 }
  75
  76 static int mcb_lpc_remove(struct platform_device *pdev)
  77 {
  78         struct priv *priv = platform_get_drvdata(pdev);
  79
  80         mcb_release_bus(priv->bus);
  81
  82         return 0;
  83 }
  84
  85 static struct platform_device *mcb_lpc_pdev;
  86
  87 static int mcb_lpc_create_platform_device(const struct dmi_system_id *id)
  88 {
  89         struct resource *res = id->driver_data;
  90         int ret;
  91
  92         mcb_lpc_pdev = platform_device_alloc("mcb-lpc", -1);
  93         if (!mcb_lpc_pdev)
  94                 return -ENOMEM;
  95
  96         ret = platform_device_add_resources(mcb_lpc_pdev, res, 1);
  97         if (ret)
  98                 goto out_put;
  99
 100         ret = platform_device_add(mcb_lpc_pdev);
 101         if (ret)
 102                 goto out_put;
 103
 104         return 0;
 105
 106 out_put:
 107         platform_device_put(mcb_lpc_pdev);
 108         return ret;
 109 }
 110
 111 static struct resource sc24_fpga_resource = {
 112         .start = 0xe000e000,
 113         .end = 0xe000e000 + CHAM_HEADER_SIZE,
 114         .flags = IORESOURCE_MEM,
 115 };
 116
 117 static struct platform_driver mcb_lpc_driver = {
 118         .driver         = {
 119                 .name = "mcb-lpc",
 120         },
 121         .probe          = mcb_lpc_probe,
 122         .remove         = mcb_lpc_remove,
 123 };
 124
 125 static const struct dmi_system_id mcb_lpc_dmi_table[] = {
 126         {
 127                 .ident = "SC24",
 128                 .matches = {
 129                         DMI_MATCH(DMI_SYS_VENDOR, "MEN"),
 130                         DMI_MATCH(DMI_PRODUCT_VERSION, "14SC24"),
 131                 },
 132                 .driver_data = (void *)&sc24_fpga_resource,
 133                 .callback = mcb_lpc_create_platform_device,
 134         },
 135         {}
 136 };
 137 MODULE_DEVICE_TABLE(dmi, mcb_lpc_dmi_table);
 138
 139 static int __init mcb_lpc_init(void)
 140 {
 141         if (!dmi_check_system(mcb_lpc_dmi_table))
 142                 return -ENODEV;
 143
 144         return platform_driver_register(&mcb_lpc_driver);
 145 }
 146
 147 static void __exit mcb_lpc_exit(void)
 148 {
 149         platform_device_unregister(mcb_lpc_pdev);
 150         platform_driver_unregister(&mcb_lpc_driver);
 151 }
 152
 153 module_init(mcb_lpc_init);
 154 module_exit(mcb_lpc_exit);
 155
 156 MODULE_AUTHOR("Andreas Werner <[email protected]>");
 157 MODULE_LICENSE("GPL");
 158 MODULE_DESCRIPTION("MCB over LPC support");