When registering protocol events, use the optional .is_notify_supported
callback provided by the protocol to check if that specific notification
type is available for that particular resource on the running system,
marking it as unsupported otherwise.
Then, when a notification enable request is received, return an error if
it was previously marked as unsuppported, so avoiding to send a needless
notification enable command and check the returned value for failure.
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
drivers/firmware/arm_scmi/notify.c | 17 ++++++++++++++++-
drivers/firmware/arm_scmi/notify.h | 4 ++++
2 files changed, 20 insertions(+), 1 deletion(-)
@@ -99,6 +99,7 @@
#define PROTO_ID_MASK GENMASK(31, 24)
#define EVT_ID_MASK GENMASK(23, 16)
#define SRC_ID_MASK GENMASK(15, 0)
+#define NOTIF_UNSUPP -1
/*
* Builds an unsigned 32bit key from the given input tuple to be used
@@ -788,6 +789,7 @@ int scmi_register_protocol_events(const struct scmi_handle *handle, u8 proto_id,
pd->ph = ph;
for (i = 0; i < ee->num_events; i++, evt++) {
+ int id;
struct scmi_registered_event *r_evt;
r_evt = devm_kzalloc(ni->handle->dev, sizeof(*r_evt),
@@ -809,6 +811,11 @@ int scmi_register_protocol_events(const struct scmi_handle *handle, u8 proto_id,
if (!r_evt->report)
return -ENOMEM;
+ for (id = 0; id < r_evt->num_sources; id++)
+ if (ee->ops->is_notify_supported &&
+ !ee->ops->is_notify_supported(ph, r_evt->evt->id, id))
+ refcount_set(&r_evt->sources[id], NOTIF_UNSUPP);
+
pd->registered_events[i] = r_evt;
/* Ensure events are updated */
smp_wmb();
@@ -1166,7 +1173,13 @@ static inline int __scmi_enable_evt(struct scmi_registered_event *r_evt,
int ret = 0;
sid = &r_evt->sources[src_id];
- if (refcount_read(sid) == 0) {
+ if (refcount_read(sid) == NOTIF_UNSUPP) {
+ dev_dbg(r_evt->proto->ph->dev,
+ "Notification NOT supported - proto_id:%d evt_id:%d src_id:%d",
+ r_evt->proto->id, r_evt->evt->id,
+ src_id);
+ ret = -EOPNOTSUPP;
+ } else if (refcount_read(sid) == 0) {
ret = REVT_NOTIFY_ENABLE(r_evt, r_evt->evt->id,
src_id);
if (!ret)
@@ -1179,6 +1192,8 @@ static inline int __scmi_enable_evt(struct scmi_registered_event *r_evt,
} else {
for (; num_sources; src_id++, num_sources--) {
sid = &r_evt->sources[src_id];
+ if (refcount_read(sid) == NOTIF_UNSUPP)
+ continue;
if (refcount_dec_and_test(sid))
REVT_NOTIFY_DISABLE(r_evt,
r_evt->evt->id, src_id);
@@ -35,6 +35,8 @@ struct scmi_protocol_handle;
/**
* struct scmi_event_ops - Protocol helpers called by the notification core.
+ * @is_notify_supported: Return 0 if the specified notification for the
+ * specified resource (src_id) is supported.
* @get_num_sources: Returns the number of possible events' sources for this
* protocol
* @set_notify_enabled: Enable/disable the required evt_id/src_id notifications
@@ -50,6 +52,8 @@ struct scmi_protocol_handle;
* process context.
*/
struct scmi_event_ops {
+ bool (*is_notify_supported)(const struct scmi_protocol_handle *ph,
+ u8 evt_id, u32 src_id);
int (*get_num_sources)(const struct scmi_protocol_handle *ph);
int (*set_notify_enabled)(const struct scmi_protocol_handle *ph,
u8 evt_id, u32 src_id, bool enabled);