| Message ID | 20191021034927.19300-1-ran.wang_1@nxp.com (mailing list archive) |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
| Series | [v7,1/3] PM: wakeup: Add routine to help fetch wakeup source object. | expand |
On Mon, Oct 21, 2019 at 5:49 AM Ran Wang <ran.wang_1@nxp.com> wrote: > > Some user might want to go through all registered wakeup sources > and doing things accordingly. For example, SoC PM driver might need to > do HW programming to prevent powering down specific IP which wakeup > source depending on. So add this API to help walk through all registered > wakeup source objects on that list and return them one by one. > > Signed-off-by: Ran Wang <ran.wang_1@nxp.com> > Tested-by: Leonard Crestez <leonard.crestez@nxp.com> > --- > Change in v7: > - Remove define of member *dev in wake_irq to fix conflict with commit > c8377adfa781 ("PM / wakeup: Show wakeup sources stats in sysfs"), user > will use ws->dev->parent instead. > - Remove '#include <linux/of_device.h>' because it is not used. > > Change in v6: > - Add wakeup_source_get_star() and wakeup_source_get_stop() to aligned > with wakeup_sources_stats_seq_start/nex/stop. > > Change in v5: > - Update commit message, add decription of walk through all wakeup > source objects. > - Add SCU protection in function wakeup_source_get_next(). > - Rename wakeup_source member 'attached_dev' to 'dev' and move it up > (before wakeirq). > > Change in v4: > - None. > > Change in v3: > - Adjust indentation of *attached_dev;. > > Change in v2: > - None. > > drivers/base/power/wakeup.c | 37 +++++++++++++++++++++++++++++++++++++ > include/linux/pm_wakeup.h | 3 +++ > 2 files changed, 40 insertions(+) > > diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c > index 5817b51..dee1b09 100644 > --- a/drivers/base/power/wakeup.c > +++ b/drivers/base/power/wakeup.c > @@ -248,6 +248,43 @@ void wakeup_source_unregister(struct wakeup_source *ws) > EXPORT_SYMBOL_GPL(wakeup_source_unregister); > > /** > + * wakeup_source_get_star - Begin a walk on wakeup source list The "get" in the name suggests acquiring a reference of some kind which doesn't happen here. What about renaming it to wakeup_sources_walk_start()? > + * @srcuidx: Lock index allocated for this caller. > + */ > +struct wakeup_source *wakeup_source_get_start(int *srcuidx) I don't quite like the calling convention here with passing an int pointer to get the SRCU index back. What about splitting this into, say, wakeup_sources_read_lock() (that will return the SRCU index) and wakeup_sources_walk_start() (that will return the first list entry)? Then, you could do something like idx = wakeup_sources_read_lock(); ws = wakeup_sources_walk_start(); while (ws) { stuff ws = wakeup_sources_walk_next(); } wakeup_sources_read_unlock(idx); Or even define for_each_wakeup_source(ws) as for (ws = wakeup_sources_walk_start(); ws; ws = wakeup_sources_walk_next()) and use that under a _read_lock()/_read_unlock() pair?
diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c index 5817b51..dee1b09 100644 --- a/drivers/base/power/wakeup.c +++ b/drivers/base/power/wakeup.c @@ -248,6 +248,43 @@ void wakeup_source_unregister(struct wakeup_source *ws) EXPORT_SYMBOL_GPL(wakeup_source_unregister); /** + * wakeup_source_get_star - Begin a walk on wakeup source list + * @srcuidx: Lock index allocated for this caller. + */ +struct wakeup_source *wakeup_source_get_start(int *srcuidx) +{ + struct list_head *ws_head = &wakeup_sources; + + *srcuidx = srcu_read_lock(&wakeup_srcu); + + return list_entry_rcu(ws_head->next, struct wakeup_source, entry); +} +EXPORT_SYMBOL_GPL(wakeup_source_get_start); + +/** + * wakeup_source_get_next - Get next wakeup source from the list + * @ws: Previous wakeup source object + */ +struct wakeup_source *wakeup_source_get_next(struct wakeup_source *ws) +{ + struct list_head *ws_head = &wakeup_sources; + + return list_next_or_null_rcu(ws_head, &ws->entry, + struct wakeup_source, entry); +} +EXPORT_SYMBOL_GPL(wakeup_source_get_next); + +/** + * wakeup_source_get_stop - Stop a walk on wakeup source list + * @idx: Dedicated lock index of this caller. + */ +void wakeup_source_get_stop(int idx) +{ + srcu_read_unlock(&wakeup_srcu, idx); +} +EXPORT_SYMBOL_GPL(wakeup_source_get_stop); + +/** * device_wakeup_attach - Attach a wakeup source object to a device object. * @dev: Device to handle. * @ws: Wakeup source object to attach to @dev. diff --git a/include/linux/pm_wakeup.h b/include/linux/pm_wakeup.h index 661efa0..172e76c 100644 --- a/include/linux/pm_wakeup.h +++ b/include/linux/pm_wakeup.h @@ -92,6 +92,9 @@ extern void wakeup_source_remove(struct wakeup_source *ws); extern struct wakeup_source *wakeup_source_register(struct device *dev, const char *name); extern void wakeup_source_unregister(struct wakeup_source *ws); +extern struct wakeup_source *wakeup_source_get_start(int *srcuidx); +extern struct wakeup_source *wakeup_source_get_next(struct wakeup_source *ws); +extern void wakeup_source_get_stop(int idx); extern int device_wakeup_enable(struct device *dev); extern int device_wakeup_disable(struct device *dev); extern void device_set_wakeup_capable(struct device *dev, bool capable);