drivers/dax/hmem/hmem.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/platform_device.h>
   3 #include <linux/memregion.h>
   4 #include <linux/module.h>
   5 #include <linux/pfn_t.h>
   6 #include "../bus.h"
   7
   8 static bool region_idle;
   9 module_param_named(region_idle, region_idle, bool, 0644);
  10
  11 static int dax_hmem_probe(struct platform_device *pdev)
  12 {
  13         struct device *dev = &pdev->dev;
  14         struct dax_region *dax_region;
  15         struct memregion_info *mri;
  16         struct dev_dax_data data;
  17         struct dev_dax *dev_dax;
  18         struct resource *res;
  19         struct range range;
  20
  21         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  22         if (!res)
  23                 return -ENOMEM;
  24
  25         mri = dev->platform_data;
  26         range.start = res->start;
  27         range.end = res->end;
  28         dax_region = alloc_dax_region(dev, pdev->id, &range, mri->target_node,
  29                         PMD_SIZE, 0);
  30         if (!dax_region)
  31                 return -ENOMEM;
  32
  33         data = (struct dev_dax_data) {
  34                 .dax_region = dax_region,
  35                 .id = -1,
  36                 .size = region_idle ? 0 : resource_size(res),
  37         };
  38         dev_dax = devm_create_dev_dax(&data);
  39         if (IS_ERR(dev_dax))
  40                 return PTR_ERR(dev_dax);
  41
  42         /* child dev_dax instances now own the lifetime of the dax_region */
  43         dax_region_put(dax_region);
  44         return 0;
  45 }
  46
  47 static int dax_hmem_remove(struct platform_device *pdev)
  48 {
  49         /* devm handles teardown */
  50         return 0;
  51 }
  52
  53 static struct platform_driver dax_hmem_driver = {
  54         .probe = dax_hmem_probe,
  55         .remove = dax_hmem_remove,
  56         .driver = {
  57                 .name = "hmem",
  58         },
  59 };
  60
  61 module_platform_driver(dax_hmem_driver);
  62
  63 MODULE_ALIAS("platform:hmem*");
  64 MODULE_LICENSE("GPL v2");
  65 MODULE_AUTHOR("Intel Corporation");