aoc: notify aocd when aoc_request_on times out

Test: on device
Bug: 309950738
Change-Id: I60c14d8d89847c0681ff285b1f4d26d37858be18
Signed-off-by: Alex Iacobucci <alexiacobucci@google.com>

4 files changed, 34 insertions, 0 deletions

diff --git a/Documentation/ABI/sysfs-devices-platform-aoc b/Documentation/ABI/sysfs-devices-platform-aoc
new file mode 100644
index 0000000..81a5b6c
--- /dev/null
+++ b/Documentation/ABI/sysfs-devices-platform-aoc
@@ -0,0 +1,9 @@
+What:		/sys/devices/platform/[0-9]+.aoc/notify_timeout_aoc_status
+Date:		Nov 2023
+KernelVersion:	2.6.22
+Contact:	alexiacobucci@google.com
+Description:
+		Read-only node used by AOC's kernel driver to notify userspace
+		if a request for AOC fabric to reach a certain state has timed out.
+
+Users:		AOC kernel driver, aocd process in userspace.
diff --git a/aoc.c b/aoc.c
index 868856b..654306b 100644
--- a/aoc.c
+++ b/aoc.c
@@ -1014,6 +1014,14 @@ static ssize_t sensor_power_enable_store(struct device *dev,
 
 static DEVICE_ATTR_WO(sensor_power_enable);
 
+static ssize_t notify_timeout_aoc_status_show(struct device *dev, struct device_attribute *attr,
+			     char *buf)
+{
+	return 0;
+}
+
+static DEVICE_ATTR_RO(notify_timeout_aoc_status);
+
 static struct attribute *aoc_attrs[] = {
 	&dev_attr_firmware.attr,
 	&dev_attr_revision.attr,
@@ -1027,6 +1035,7 @@ static struct attribute *aoc_attrs[] = {
 	&dev_attr_sensor_power_enable.attr,
 	&dev_attr_force_reload.attr,
 	&dev_attr_dmic_power_enable.attr,
+	&dev_attr_notify_timeout_aoc_status.attr,
 	NULL
 };
 
@@ -1569,6 +1578,7 @@ static void aoc_take_offline(struct aoc_prvdata *prvdata)
 			dev_err(prvdata->dev, "timed out waiting for aoc_ack\n");
 			if (prvdata->protected_by_gsa)
 				dev_err(prvdata->dev, "skipping GSA commands");
+			notify_timeout_aoc_status();
 			return;
 		}
 	}
@@ -1635,6 +1645,16 @@ exit:
 	atomic_dec(&prvdata->aoc_process_active);
 }
 
+void notify_timeout_aoc_status(void)
+{
+	if (aoc_platform_device == NULL) {
+		pr_err("AOC platform device is undefined, can't notify aocd\n");
+		return;
+	}
+	sysfs_notify(&aoc_platform_device->dev.kobj, NULL,
+		"notify_timeout_aoc_status");
+}
+
 void aoc_set_map_handler(struct aoc_service_dev *dev, aoc_map_handler handler,
 			 void *ctx)
 {
diff --git a/aoc.h b/aoc.h
index 44b4539..2dc2e8a 100644
--- a/aoc.h
+++ b/aoc.h
@@ -287,6 +287,8 @@ u32 dt_property(struct device_node *node, const char *key);
 
 void configure_crash_interrupts(struct aoc_prvdata *prvdata, bool enable);
 
+void notify_timeout_aoc_status(void);
+
 #define AOC_SERVICE_NAME_LENGTH 32
 
 /* Rings should have the ring flag set, slots = 1, size = ring size
diff --git a/aoc_v1.c b/aoc_v1.c
index 1147c43..e67937f 100644
--- a/aoc_v1.c
+++ b/aoc_v1.c
@@ -142,6 +142,7 @@ int aoc_watchdog_restart(struct aoc_prvdata *prvdata,
 		aoc_req_rc = wait_for_aoc_status(prvdata, true);
 		if (aoc_req_rc) {
 			dev_err(prvdata->dev, "timed out waiting for aoc_ack\n");
+			notify_timeout_aoc_status();
 			continue;
 		}
 		dev_info(prvdata->dev, "resetting aoc\n");
@@ -174,6 +175,8 @@ int aoc_watchdog_restart(struct aoc_prvdata *prvdata,
 
 	if (aoc_req_rc && *(aoc_module_params->aoc_panic_on_req_timeout)) {
 		dev_err(prvdata->dev, "timed out too many times waiting for aoc_ack, triggering kernel panic\n");
+		/* Sleep to ensure aocd can process notification of timeout before panic */
+		msleep(1000);
 		panic("AoC kernel panic: timed out waiting for aoc_ack");
 	}