/*
* Main SSAM/SSH controller structure and functionality.
*
*/
#include <linux/acpi.h>
return NULL;
}
+/**
+ * ssam_nf_refcount_dec_free() - Decrement reference-/activation-count of the
+ * given event and free its entry if the reference count reaches zero.
+ * @nf: The notifier system reference.
+ * @reg: The registry used to enable/disable the event.
+ * @id: The event ID.
+ *
+ * Decrements the reference-/activation-count of the specified event, freeing
+ * its entry if it reaches zero.
+ *
+ * Note: ``nf->lock`` must be held when calling this function.
+ */
+static void ssam_nf_refcount_dec_free(struct ssam_nf *nf,
+ struct ssam_event_registry reg,
+ struct ssam_event_id id)
+{
+ struct ssam_nf_refcount_entry *entry;
+
+ lockdep_assert_held(&nf->lock);
+
+ entry = ssam_nf_refcount_dec(nf, reg, id);
+ if (entry && entry->refcount == 0)
+ kfree(entry);
+}
+
/**
* ssam_nf_refcount_empty() - Test if the notification system has any
* enabled/active events.
{
int status;
- status = __ssam_ssh_event_request(ctrl, reg, reg.cid_enable, id, flags);
+ status = __ssam_ssh_event_request(ctrl, reg, reg.cid_disable, id, flags);
if (status < 0 && status != -EINVAL) {
ssam_err(ctrl,
/* -- Top-level event registry interface. ----------------------------------- */
+/**
+ * ssam_nf_refcount_enable() - Enable event for reference count entry if it has
+ * not already been enabled.
+ * @ctrl: The controller to enable the event on.
+ * @entry: The reference count entry for the event to be enabled.
+ * @flags: The flags used for enabling the event on the EC.
+ *
+ * Enable the event associated with the given reference count entry if the
+ * reference count equals one, i.e. the event has not previously been enabled.
+ * If the event has already been enabled (i.e. reference count not equal to
+ * one), check that the flags used for enabling match and warn about this if
+ * they do not.
+ *
+ * This does not modify the reference count itself, which is done with
+ * ssam_nf_refcount_inc() / ssam_nf_refcount_dec().
+ *
+ * Note: ``nf->lock`` must be held when calling this function.
+ *
+ * Return: Returns zero on success. If the event is enabled by this call,
+ * returns the status of the event-enable EC command.
+ */
+static int ssam_nf_refcount_enable(struct ssam_controller *ctrl,
+ struct ssam_nf_refcount_entry *entry, u8 flags)
+{
+ const struct ssam_event_registry reg = entry->key.reg;
+ const struct ssam_event_id id = entry->key.id;
+ struct ssam_nf *nf = &ctrl->cplt.event.notif;
+ int status;
+
+ lockdep_assert_held(&nf->lock);
+
+ ssam_dbg(ctrl, "enabling event (reg: %#04x, tc: %#04x, iid: %#04x, rc: %d)\n",
+ reg.target_category, id.target_category, id.instance, entry->refcount);
+
+ if (entry->refcount == 1) {
+ status = ssam_ssh_event_enable(ctrl, reg, id, flags);
+ if (status)
+ return status;
+
+ entry->flags = flags;
+
+ } else if (entry->flags != flags) {
+ ssam_warn(ctrl,
+ "inconsistent flags when enabling event: got %#04x, expected %#04x (reg: %#04x, tc: %#04x, iid: %#04x)\n",
+ flags, entry->flags, reg.target_category, id.target_category,
+ id.instance);
+ }
+
+ return 0;
+}
+
+/**
+ * ssam_nf_refcount_disable_free() - Disable event for reference count entry if it is
+ * no longer in use and free the corresponding entry.
+ * @ctrl: The controller to disable the event on.
+ * @entry: The reference count entry for the event to be disabled.
+ * @flags: The flags used for enabling the event on the EC.
+ *
+ * If the reference count equals zero, i.e. the event is no longer requested by
+ * any client, the event will be disabled and the corresponding reference count
+ * entry freed. The reference count entry must not be used any more after a
+ * call to this function.
+ *
+ * Also checks if the flags used for disabling the event match the flags used
+ * for enabling the event and warns if they do not (regardless of reference
+ * count).
+ *
+ * This does not modify the reference count itself, which is done with
+ * ssam_nf_refcount_inc() / ssam_nf_refcount_dec().
+ *
+ * Note: ``nf->lock`` must be held when calling this function.
+ *
+ * Return: Returns zero on success. If the event is disabled by this call,
+ * returns the status of the event-enable EC command.
+ */
+static int ssam_nf_refcount_disable_free(struct ssam_controller *ctrl,
+ struct ssam_nf_refcount_entry *entry, u8 flags)
+{
+ const struct ssam_event_registry reg = entry->key.reg;
+ const struct ssam_event_id id = entry->key.id;
+ struct ssam_nf *nf = &ctrl->cplt.event.notif;
+ int status = 0;
+
+ lockdep_assert_held(&nf->lock);
+
+ ssam_dbg(ctrl, "disabling event (reg: %#04x, tc: %#04x, iid: %#04x, rc: %d)\n",
+ reg.target_category, id.target_category, id.instance, entry->refcount);
+
+ if (entry->flags != flags) {
+ ssam_warn(ctrl,
+ "inconsistent flags when disabling event: got %#04x, expected %#04x (reg: %#04x, tc: %#04x, iid: %#04x)\n",
+ flags, entry->flags, reg.target_category, id.target_category,
+ id.instance);
+ }
+
+ if (entry->refcount == 0) {
+ status = ssam_ssh_event_disable(ctrl, reg, id, flags);
+ kfree(entry);
+ }
+
+ return status;
+}
+
/**
* ssam_notifier_register() - Register an event notifier.
* @ctrl: The controller to register the notifier on.
* @n: The event notifier to register.
*
- * Register an event notifier and increment the usage counter of the
- * associated SAM event. If the event was previously not enabled, it will be
- * enabled during this call.
+ * Register an event notifier. Increment the usage counter of the associated
+ * SAM event if the notifier is not marked as an observer. If the event is not
+ * marked as an observer and is currently not enabled, it will be enabled
+ * during this call. If the notifier is marked as an observer, no attempt will
+ * be made at enabling any event and no reference count will be modified.
+ *
+ * Notifiers marked as observers do not need to be associated with one specific
+ * event, i.e. as long as no event matching is performed, only the event target
+ * category needs to be set.
*
* Return: Returns zero on success, %-ENOSPC if there have already been
* %INT_MAX notifiers for the event ID/type associated with the notifier block
* for the specific associated event, returns the status of the event-enable
* EC-command.
*/
-int ssam_notifier_register(struct ssam_controller *ctrl,
- struct ssam_event_notifier *n)
+int ssam_notifier_register(struct ssam_controller *ctrl, struct ssam_event_notifier *n)
{
u16 rqid = ssh_tc_to_rqid(n->event.id.target_category);
- struct ssam_nf_refcount_entry *entry;
+ struct ssam_nf_refcount_entry *entry = NULL;
struct ssam_nf_head *nf_head;
struct ssam_nf *nf;
int status;
mutex_lock(&nf->lock);
- entry = ssam_nf_refcount_inc(nf, n->event.reg, n->event.id);
- if (IS_ERR(entry)) {
- mutex_unlock(&nf->lock);
- return PTR_ERR(entry);
+ if (!(n->flags & SSAM_EVENT_NOTIFIER_OBSERVER)) {
+ entry = ssam_nf_refcount_inc(nf, n->event.reg, n->event.id);
+ if (IS_ERR(entry)) {
+ mutex_unlock(&nf->lock);
+ return PTR_ERR(entry);
+ }
}
- ssam_dbg(ctrl, "enabling event (reg: %#04x, tc: %#04x, iid: %#04x, rc: %d)\n",
- n->event.reg.target_category, n->event.id.target_category,
- n->event.id.instance, entry->refcount);
-
status = ssam_nfblk_insert(nf_head, &n->base);
if (status) {
- entry = ssam_nf_refcount_dec(nf, n->event.reg, n->event.id);
- if (entry->refcount == 0)
- kfree(entry);
+ if (entry)
+ ssam_nf_refcount_dec_free(nf, n->event.reg, n->event.id);
mutex_unlock(&nf->lock);
return status;
}
- if (entry->refcount == 1) {
- status = ssam_ssh_event_enable(ctrl, n->event.reg, n->event.id,
- n->event.flags);
+ if (entry) {
+ status = ssam_nf_refcount_enable(ctrl, entry, n->event.flags);
if (status) {
ssam_nfblk_remove(&n->base);
- kfree(ssam_nf_refcount_dec(nf, n->event.reg, n->event.id));
+ ssam_nf_refcount_dec_free(nf, n->event.reg, n->event.id);
mutex_unlock(&nf->lock);
synchronize_srcu(&nf_head->srcu);
return status;
}
-
- entry->flags = n->event.flags;
-
- } else if (entry->flags != n->event.flags) {
- ssam_warn(ctrl,
- "inconsistent flags when enabling event: got %#04x, expected %#04x (reg: %#04x, tc: %#04x, iid: %#04x)\n",
- n->event.flags, entry->flags, n->event.reg.target_category,
- n->event.id.target_category, n->event.id.instance);
}
mutex_unlock(&nf->lock);
* @ctrl: The controller the notifier has been registered on.
* @n: The event notifier to unregister.
*
- * Unregister an event notifier and decrement the usage counter of the
- * associated SAM event. If the usage counter reaches zero, the event will be
- * disabled.
+ * Unregister an event notifier. Decrement the usage counter of the associated
+ * SAM event if the notifier is not marked as an observer. If the usage counter
+ * reaches zero, the event will be disabled.
*
* Return: Returns zero on success, %-ENOENT if the given notifier block has
* not been registered on the controller. If the given notifier block was the
* last one associated with its specific event, returns the status of the
* event-disable EC-command.
*/
-int ssam_notifier_unregister(struct ssam_controller *ctrl,
- struct ssam_event_notifier *n)
+int ssam_notifier_unregister(struct ssam_controller *ctrl, struct ssam_event_notifier *n)
{
u16 rqid = ssh_tc_to_rqid(n->event.id.target_category);
struct ssam_nf_refcount_entry *entry;
return -ENOENT;
}
- entry = ssam_nf_refcount_dec(nf, n->event.reg, n->event.id);
- if (WARN_ON(!entry)) {
- /*
- * If this does not return an entry, there's a logic error
- * somewhere: The notifier block is registered, but the event
- * refcount entry is not there. Remove the notifier block
- * anyways.
- */
- status = -ENOENT;
- goto remove;
- }
-
- ssam_dbg(ctrl, "disabling event (reg: %#04x, tc: %#04x, iid: %#04x, rc: %d)\n",
- n->event.reg.target_category, n->event.id.target_category,
- n->event.id.instance, entry->refcount);
-
- if (entry->flags != n->event.flags) {
- ssam_warn(ctrl,
- "inconsistent flags when disabling event: got %#04x, expected %#04x (reg: %#04x, tc: %#04x, iid: %#04x)\n",
- n->event.flags, entry->flags, n->event.reg.target_category,
- n->event.id.target_category, n->event.id.instance);
- }
+ /*
+ * If this is an observer notifier, do not attempt to disable the
+ * event, just remove it.
+ */
+ if (!(n->flags & SSAM_EVENT_NOTIFIER_OBSERVER)) {
+ entry = ssam_nf_refcount_dec(nf, n->event.reg, n->event.id);
+ if (WARN_ON(!entry)) {
+ /*
+ * If this does not return an entry, there's a logic
+ * error somewhere: The notifier block is registered,
+ * but the event refcount entry is not there. Remove
+ * the notifier block anyways.
+ */
+ status = -ENOENT;
+ goto remove;
+ }
- if (entry->refcount == 0) {
- status = ssam_ssh_event_disable(ctrl, n->event.reg, n->event.id,
- n->event.flags);
- kfree(entry);
+ status = ssam_nf_refcount_disable_free(ctrl, entry, n->event.flags);
}
remove:
}
EXPORT_SYMBOL_GPL(ssam_notifier_unregister);
+/**
+ * ssam_controller_event_enable() - Enable the specified event.
+ * @ctrl: The controller to enable the event for.
+ * @reg: The event registry to use for enabling the event.
+ * @id: The event ID specifying the event to be enabled.
+ * @flags: The SAM event flags used for enabling the event.
+ *
+ * Increment the event reference count of the specified event. If the event has
+ * not been enabled previously, it will be enabled by this call.
+ *
+ * Note: In general, ssam_notifier_register() with a non-observer notifier
+ * should be preferred for enabling/disabling events, as this will guarantee
+ * proper ordering and event forwarding in case of errors during event
+ * enabling/disabling.
+ *
+ * Return: Returns zero on success, %-ENOSPC if the reference count for the
+ * specified event has reached its maximum, %-ENOMEM if the corresponding event
+ * entry could not be allocated. If this is the first time that this event has
+ * been enabled (i.e. the reference count was incremented from zero to one by
+ * this call), returns the status of the event-enable EC-command.
+ */
+int ssam_controller_event_enable(struct ssam_controller *ctrl,
+ struct ssam_event_registry reg,
+ struct ssam_event_id id, u8 flags)
+{
+ u16 rqid = ssh_tc_to_rqid(id.target_category);
+ struct ssam_nf *nf = &ctrl->cplt.event.notif;
+ struct ssam_nf_refcount_entry *entry;
+ int status;
+
+ if (!ssh_rqid_is_event(rqid))
+ return -EINVAL;
+
+ mutex_lock(&nf->lock);
+
+ entry = ssam_nf_refcount_inc(nf, reg, id);
+ if (IS_ERR(entry)) {
+ mutex_unlock(&nf->lock);
+ return PTR_ERR(entry);
+ }
+
+ status = ssam_nf_refcount_enable(ctrl, entry, flags);
+ if (status) {
+ ssam_nf_refcount_dec_free(nf, reg, id);
+ mutex_unlock(&nf->lock);
+ return status;
+ }
+
+ mutex_unlock(&nf->lock);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ssam_controller_event_enable);
+
+/**
+ * ssam_controller_event_disable() - Disable the specified event.
+ * @ctrl: The controller to disable the event for.
+ * @reg: The event registry to use for disabling the event.
+ * @id: The event ID specifying the event to be disabled.
+ * @flags: The flags used when enabling the event.
+ *
+ * Decrement the reference count of the specified event. If the reference count
+ * reaches zero, the event will be disabled.
+ *
+ * Note: In general, ssam_notifier_register()/ssam_notifier_unregister() with a
+ * non-observer notifier should be preferred for enabling/disabling events, as
+ * this will guarantee proper ordering and event forwarding in case of errors
+ * during event enabling/disabling.
+ *
+ * Return: Returns zero on success, %-ENOENT if the given event has not been
+ * enabled on the controller. If the reference count of the event reaches zero
+ * during this call, returns the status of the event-disable EC-command.
+ */
+int ssam_controller_event_disable(struct ssam_controller *ctrl,
+ struct ssam_event_registry reg,
+ struct ssam_event_id id, u8 flags)
+{
+ u16 rqid = ssh_tc_to_rqid(id.target_category);
+ struct ssam_nf *nf = &ctrl->cplt.event.notif;
+ struct ssam_nf_refcount_entry *entry;
+ int status;
+
+ if (!ssh_rqid_is_event(rqid))
+ return -EINVAL;
+
+ mutex_lock(&nf->lock);
+
+ entry = ssam_nf_refcount_dec(nf, reg, id);
+ if (!entry) {
+ mutex_unlock(&nf->lock);
+ return -ENOENT;
+ }
+
+ status = ssam_nf_refcount_disable_free(ctrl, entry, flags);
+
+ mutex_unlock(&nf->lock);
+ return status;
+}
+EXPORT_SYMBOL_GPL(ssam_controller_event_disable);
+
/**
* ssam_notifier_disable_registered() - Disable events for all registered
* notifiers.
* interrupt, and let the SAM resume callback during the controller
* resume process clear it.
*/
- const int irqf = IRQF_SHARED | IRQF_ONESHOT |
- IRQF_TRIGGER_RISING | IRQF_NO_AUTOEN;
+ const int irqf = IRQF_ONESHOT | IRQF_TRIGGER_RISING | IRQF_NO_AUTOEN;
gpiod = gpiod_get(dev, "ssam_wakeup-int", GPIOD_ASIS);
if (IS_ERR(gpiod))
projects / J-linux.git / blobdiff