target/linux/layerscape/patches-5.4/813-pm-0004-PM-wakeup-Add-routine-to-help-fetch-wakeup-source-ob.patch

   1 From a9647655a2240148b7b6d29227dc76e9d6f12766 Mon Sep 17 00:00:00 2001
   2 From: Ran Wang <ran.wang_1@nxp.com>
   3 Date: Thu, 24 Oct 2019 16:36:14 +0800
   4 Subject: [PATCH] PM: wakeup: Add routine to help fetch wakeup source object.
   5
   6 Some user might want to go through all registered wakeup sources
   7 and doing things accordingly. For example, SoC PM driver might need to
   8 do HW programming to prevent powering down specific IP which wakeup
   9 source depending on. So add this API to help walk through all registered
  10 wakeup source objects on that list and return them one by one.
  11
  12 Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
  13 Tested-by: Leonard Crestez <leonard.crestez@nxp.com>
  14 Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
  15 Acked-by: Anson Huang <Anson.Huang@nxp.com>
  16 ---
  17  drivers/base/power/wakeup.c | 54 +++++++++++++++++++++++++++++++++++++++++++++
  18  include/linux/pm_wakeup.h   |  9 ++++++++
  19  2 files changed, 63 insertions(+)
  20
  21 --- a/drivers/base/power/wakeup.c
  22 +++ b/drivers/base/power/wakeup.c
  23 @@ -250,6 +250,60 @@ void wakeup_source_unregister(struct wak
  24  EXPORT_SYMBOL_GPL(wakeup_source_unregister);
  25
  26  /**
  27 + * wakeup_sources_read_lock - Lock wakeup source list for read.
  28 + *
  29 + * Returns an index of srcu lock for struct wakeup_srcu.
  30 + * This index must be passed to the matching wakeup_sources_read_unlock().
  31 + */
  32 +int wakeup_sources_read_lock(void)
  33 +{
  34 +       return srcu_read_lock(&wakeup_srcu);
  35 +}
  36 +EXPORT_SYMBOL_GPL(wakeup_sources_read_lock);
  37 +
  38 +/**
  39 + * wakeup_sources_read_unlock - Unlock wakeup source list.
  40 + * @idx: return value from corresponding wakeup_sources_read_lock()
  41 + */
  42 +void wakeup_sources_read_unlock(int idx)
  43 +{
  44 +       srcu_read_unlock(&wakeup_srcu, idx);
  45 +}
  46 +EXPORT_SYMBOL_GPL(wakeup_sources_read_unlock);
  47 +
  48 +/**
  49 + * wakeup_sources_walk_start - Begin a walk on wakeup source list
  50 + *
  51 + * Returns first object of the list of wakeup sources.
  52 + *
  53 + * Note that to be safe, wakeup sources list needs to be locked by calling
  54 + * wakeup_source_read_lock() for this.
  55 + */
  56 +struct wakeup_source *wakeup_sources_walk_start(void)
  57 +{
  58 +       struct list_head *ws_head = &wakeup_sources;
  59 +
  60 +       return list_entry_rcu(ws_head->next, struct wakeup_source, entry);
  61 +}
  62 +EXPORT_SYMBOL_GPL(wakeup_sources_walk_start);
  63 +
  64 +/**
  65 + * wakeup_sources_walk_next - Get next wakeup source from the list
  66 + * @ws: Previous wakeup source object
  67 + *
  68 + * Note that to be safe, wakeup sources list needs to be locked by calling
  69 + * wakeup_source_read_lock() for this.
  70 + */
  71 +struct wakeup_source *wakeup_sources_walk_next(struct wakeup_source *ws)
  72 +{
  73 +       struct list_head *ws_head = &wakeup_sources;
  74 +
  75 +       return list_next_or_null_rcu(ws_head, &ws->entry,
  76 +                               struct wakeup_source, entry);
  77 +}
  78 +EXPORT_SYMBOL_GPL(wakeup_sources_walk_next);
  79 +
  80 +/**
  81   * device_wakeup_attach - Attach a wakeup source object to a device object.
  82   * @dev: Device to handle.
  83   * @ws: Wakeup source object to attach to @dev.
  84 --- a/include/linux/pm_wakeup.h
  85 +++ b/include/linux/pm_wakeup.h
  86 @@ -63,6 +63,11 @@ struct wakeup_source {
  87         bool                    autosleep_enabled:1;
  88  };
  89
  90 +#define for_each_wakeup_source(ws) \
  91 +       for ((ws) = wakeup_sources_walk_start();        \
  92 +            (ws);                                      \
  93 +            (ws) = wakeup_sources_walk_next((ws)))
  94 +
  95  #ifdef CONFIG_PM_SLEEP
  96
  97  /*
  98 @@ -92,6 +97,10 @@ extern void wakeup_source_remove(struct
  99  extern struct wakeup_source *wakeup_source_register(struct device *dev,
 100                                                     const char *name);
 101  extern void wakeup_source_unregister(struct wakeup_source *ws);
 102 +extern int wakeup_sources_read_lock(void);
 103 +extern void wakeup_sources_read_unlock(int idx);
 104 +extern struct wakeup_source *wakeup_sources_walk_start(void);
 105 +extern struct wakeup_source *wakeup_sources_walk_next(struct wakeup_source *ws);
 106  extern int device_wakeup_enable(struct device *dev);
 107  extern int device_wakeup_disable(struct device *dev);
 108  extern void device_set_wakeup_capable(struct device *dev, bool capable);