drivers/edac/edac_stub.c

   1 /*
   2  * common EDAC components that must be in kernel
   3  *
   4  * Author: Dave Jiang <djiang@mvista.com>
   5  *
   6  * 2007 (c) MontaVista Software, Inc.
   7  * 2010 (c) Advanced Micro Devices Inc.
   8  *          Borislav Petkov <borislav.petkov@amd.com>
   9  *
  10  * This file is licensed under the terms of the GNU General Public
  11  * License version 2. This program is licensed "as is" without any
  12  * warranty of any kind, whether express or implied.
  13  *
  14  */
  15 #include <linux/module.h>
  16 #include <linux/edac.h>
  17 #include <linux/atomic.h>
  18 #include <asm/edac.h>
  19
  20 int edac_op_state = EDAC_OPSTATE_INVAL;
  21 EXPORT_SYMBOL_GPL(edac_op_state);
  22
  23 atomic_t edac_handlers = ATOMIC_INIT(0);
  24 EXPORT_SYMBOL_GPL(edac_handlers);
  25
  26 int edac_err_assert = 0;
  27 EXPORT_SYMBOL_GPL(edac_err_assert);
  28
  29 static atomic_t edac_subsys_valid = ATOMIC_INIT(0);
  30
  31 /*
  32  * called to determine if there is an EDAC driver interested in
  33  * knowing an event (such as NMI) occurred
  34  */
  35 int edac_handler_set(void)
  36 {
  37         if (edac_op_state == EDAC_OPSTATE_POLL)
  38                 return 0;
  39
  40         return atomic_read(&edac_handlers);
  41 }
  42 EXPORT_SYMBOL_GPL(edac_handler_set);
  43
  44 /*
  45  * handler for NMI type of interrupts to assert error
  46  */
  47 void edac_atomic_assert_error(void)
  48 {
  49         edac_err_assert++;
  50 }
  51 EXPORT_SYMBOL_GPL(edac_atomic_assert_error);
  52
  53 /*
  54  * sysfs object: /sys/devices/system/edac
  55  *      need to export to other files
  56  */
  57 struct bus_type edac_subsys = {
  58         .name = "edac",
  59         .dev_name = "edac",
  60 };
  61 EXPORT_SYMBOL_GPL(edac_subsys);
  62
  63 /* return pointer to the 'edac' node in sysfs */
  64 struct bus_type *edac_get_sysfs_subsys(void)
  65 {
  66         int err = 0;
  67
  68         if (atomic_read(&edac_subsys_valid))
  69                 goto out;
  70
  71         /* create the /sys/devices/system/edac directory */
  72         err = subsys_system_register(&edac_subsys, NULL);
  73         if (err) {
  74                 printk(KERN_ERR "Error registering toplevel EDAC sysfs dir\n");
  75                 return NULL;
  76         }
  77
  78 out:
  79         atomic_inc(&edac_subsys_valid);
  80         return &edac_subsys;
  81 }
  82 EXPORT_SYMBOL_GPL(edac_get_sysfs_subsys);
  83
  84 void edac_put_sysfs_subsys(void)
  85 {
  86         /* last user unregisters it */
  87         if (atomic_dec_and_test(&edac_subsys_valid))
  88                 bus_unregister(&edac_subsys);
  89 }
  90 EXPORT_SYMBOL_GPL(edac_put_sysfs_subsys);