Dump LWIS info in case of a userspace crash

1. Dump current kernel time
2. Dump Last 5 events.

Bug: 243704502
Test: manual
Change-Id: Ibc74114fa5bd619297b5ff99296d574288504320
Signed-off-by: linyuny <linyuny@google.com>

7 files changed, 60 insertions, 14 deletions

diff --git a/lwis_debug.c b/lwis_debug.c
index 7f35d71..90eaaeb 100644
--- a/lwis_debug.c
+++ b/lwis_debug.c
@@ -177,7 +177,7 @@ static int generate_device_info(struct lwis_device *lwis_dev, char *buffer, size
 }
 
 static int generate_event_states_info(struct lwis_device *lwis_dev, char *buffer,
-				      size_t buffer_size)
+				      size_t buffer_size, int lwis_event_dump_cnt)
 {
 	/* Temporary buffer to be concatenated to the main buffer. */
 	char tmp_buf[96] = {};
@@ -186,13 +186,27 @@ static int generate_event_states_info(struct lwis_device *lwis_dev, char *buffer
 	unsigned long flags;
 	struct lwis_device_event_state *state;
 	bool enabled_event_present = false;
+	int traverse_last_events_size;
 
 	if (lwis_dev == NULL) {
 		pr_err("Unknown LWIS device pointer\n");
 		return -EINVAL;
 	}
 
-	scnprintf(buffer, buffer_size, "=== LWIS EVENT STATES INFO: %s ===\n", lwis_dev->name);
+	if (lwis_event_dump_cnt >= 0 && lwis_event_dump_cnt <= EVENT_DEBUG_HISTORY_SIZE) {
+		scnprintf(tmp_buf, sizeof(tmp_buf), "=== LWIS DUMP LAST %d Received Events ===\n",
+				  lwis_event_dump_cnt);
+		strlcat(buffer, tmp_buf, buffer_size);
+		traverse_last_events_size = lwis_event_dump_cnt;
+	} else if (lwis_event_dump_cnt > EVENT_DEBUG_HISTORY_SIZE) {
+		pr_err("lwis_event_dump_cnt (%d) exceed EVENT_DEBUG_HISTORY_SIZE (%d) \n",
+			   lwis_event_dump_cnt, EVENT_DEBUG_HISTORY_SIZE);
+		return -EINVAL;
+	} else {
+		scnprintf(buffer, buffer_size, "=== LWIS EVENT STATES INFO: %s ===\n",
+				  lwis_dev->name);
+		traverse_last_events_size = EVENT_DEBUG_HISTORY_SIZE;
+	}
 
 	spin_lock_irqsave(&lwis_dev->lock, flags);
 	if (hash_empty(lwis_dev->event_states)) {
@@ -211,9 +225,18 @@ static int generate_event_states_info(struct lwis_device *lwis_dev, char *buffer
 	if (!enabled_event_present) {
 		strlcat(buffer, "No enabled events\n", buffer_size);
 	}
-	strlcat(buffer, "Last Events:\n", buffer_size);
+	if (lwis_event_dump_cnt < 0) {
+		strlcat(buffer, "Last Events:\n", buffer_size);
+	}
+
 	idx = lwis_dev->debug_info.cur_event_hist_idx;
-	for (i = 0; i < EVENT_DEBUG_HISTORY_SIZE; ++i) {
+	for (i = 0; i < traverse_last_events_size; ++i) {
+		if (lwis_event_dump_cnt >= 0) {
+			if (idx == 0) {
+				idx = EVENT_DEBUG_HISTORY_SIZE;
+			}
+			idx--;
+		}
 		state = &lwis_dev->debug_info.event_hist[idx].state;
 		/* Skip uninitialized entries */
 		if (state->event_id != 0) {
@@ -223,9 +246,11 @@ static int generate_event_states_info(struct lwis_device *lwis_dev, char *buffer
 				  lwis_dev->debug_info.event_hist[idx].timestamp);
 			strlcat(buffer, tmp_buf, buffer_size);
 		}
-		idx++;
-		if (idx >= EVENT_DEBUG_HISTORY_SIZE) {
-			idx = 0;
+		if (lwis_event_dump_cnt < 0) {
+			idx++;
+			if (idx >= EVENT_DEBUG_HISTORY_SIZE) {
+				idx = 0;
+			}
 		}
 	}
 
@@ -386,7 +411,7 @@ int lwis_debug_print_device_info(struct lwis_device *lwis_dev)
 	return 0;
 }
 
-int lwis_debug_print_event_states_info(struct lwis_device *lwis_dev)
+int lwis_debug_print_event_states_info(struct lwis_device *lwis_dev, int lwis_event_dump_cnt)
 {
 	int ret = 0;
 	/* Buffer to store information */
@@ -397,7 +422,7 @@ int lwis_debug_print_event_states_info(struct lwis_device *lwis_dev)
 		return -ENOMEM;
 	}
 
-	ret = generate_event_states_info(lwis_dev, buffer, buffer_size);
+	ret = generate_event_states_info(lwis_dev, buffer, buffer_size, lwis_event_dump_cnt);
 	if (ret) {
 		dev_err(lwis_dev->dev, "Failed to generate event states info");
 		goto exit;
@@ -485,7 +510,7 @@ static ssize_t event_states_read(struct file *fp, char __user *user_buf, size_t
 		return -ENOMEM;
 	}
 
-	ret = generate_event_states_info(lwis_dev, buffer, buffer_size);
+	ret = generate_event_states_info(lwis_dev, buffer, buffer_size, /*lwis_event_dump_cnt=*/-1);
 	if (ret) {
 		dev_err(lwis_dev->dev, "Failed to generate event states info");
 		goto exit;
diff --git a/lwis_debug.h b/lwis_debug.h
index f3defd7..4978606 100644
--- a/lwis_debug.h
+++ b/lwis_debug.h
@@ -16,7 +16,7 @@ void lwis_debug_save_register_io_to_history(struct lwis_device *lwis_dev,
 
 /* Functions to print debugging info */
 int lwis_debug_print_device_info(struct lwis_device *lwis_dev);
-int lwis_debug_print_event_states_info(struct lwis_device *lwis_dev);
+int lwis_debug_print_event_states_info(struct lwis_device *lwis_dev, int lwis_event_dump_cnt);
 int lwis_debug_print_transaction_info(struct lwis_device *lwis_dev);
 int lwis_debug_print_register_io_history(struct lwis_device *lwis_dev);
 int lwis_debug_print_buffer_info(struct lwis_device *lwis_dev);
diff --git a/lwis_device.c b/lwis_device.c
index 2387f75..b6ad02a 100644
--- a/lwis_device.c
+++ b/lwis_device.c
@@ -236,6 +236,7 @@ static int lwis_release(struct inode *node, struct file *fp)
 	mutex_lock(&lwis_dev->client_lock);
 	/* Release power if client closed without power down called */
 	if (is_client_enabled && lwis_dev->enabled > 0) {
+		lwis_device_crash_info_dump(lwis_dev);
 		lwis_dev->enabled--;
 		if (lwis_dev->enabled == 0) {
 			dev_info(lwis_dev->dev, "No more client, power down\n");
@@ -1160,6 +1161,19 @@ void lwis_device_info_dump(const char *name, void (*func)(struct lwis_device *))
 	mutex_unlock(&core.lock);
 }
 
+void lwis_device_crash_info_dump(struct lwis_device *lwis_dev)
+{
+	int dump_cnt = 5;
+	int64_t timestamp;
+
+	pr_info("LWIS Device (%s) Crash Info Dump:\n", lwis_dev->name);
+
+	/* Dump Current kernel timestamp &&  Last 5 Received Event*/
+	timestamp = ktime_to_ns(lwis_get_time());
+	dev_info(lwis_dev->dev, " AT %lld Dump Last %d Received Events:\n\n", timestamp, dump_cnt);
+	lwis_debug_print_event_states_info(lwis_dev, /*lwis_event_dump_cnt=*/dump_cnt);
+}
+
 /*
  *  lwis_base_probe: Create a device instance for each of the LWIS device.
  */
diff --git a/lwis_device.h b/lwis_device.h
index cac60d2..ea62088 100644
--- a/lwis_device.h
+++ b/lwis_device.h
@@ -413,4 +413,11 @@ void lwis_dev_power_seq_list_print(struct lwis_device_power_sequence_list *list)
  */
 void lwis_device_info_dump(const char *name, void (*func)(struct lwis_device *));
 
+/*
+ * lwis_device_crash_info_dump:
+ * Use the customized function handle to print information from each device registered in LWIS
+ * when usersapce crash.
+ */
+void lwis_device_crash_info_dump(struct lwis_device *lwis_dev);
+
 #endif /* LWIS_DEVICE_H_ */
diff --git a/platform/anchorage/lwis_platform_anchorage.c b/platform/anchorage/lwis_platform_anchorage.c
index 5f48c59..26355f9 100644
--- a/platform/anchorage/lwis_platform_anchorage.c
+++ b/platform/anchorage/lwis_platform_anchorage.c
@@ -80,7 +80,7 @@ static int lwis_iommu_fault_handler(struct iommu_fault *fault, void *param)
 	pr_err("\n");
 	lwis_debug_print_transaction_info(lwis_dev);
 	pr_err("\n");
-	lwis_debug_print_event_states_info(lwis_dev);
+	lwis_debug_print_event_states_info(lwis_dev, /*lwis_event_dump_cnt=*/-1);
 	pr_err("\n");
 	lwis_debug_print_buffer_info(lwis_dev);
 	pr_err("\n");
diff --git a/platform/busan/lwis_platform_busan.c b/platform/busan/lwis_platform_busan.c
index a6ac6a9..a34f892 100644
--- a/platform/busan/lwis_platform_busan.c
+++ b/platform/busan/lwis_platform_busan.c
@@ -77,7 +77,7 @@ static int lwis_iommu_fault_handler(struct iommu_fault *fault, void *param)
 	pr_err("\n");
 	lwis_debug_print_transaction_info(lwis_dev);
 	pr_err("\n");
-	lwis_debug_print_event_states_info(lwis_dev);
+	lwis_debug_print_event_states_info(lwis_dev, /*lwis_event_dump_cnt=*/-1);
 	pr_err("\n");
 	lwis_debug_print_buffer_info(lwis_dev);
 	pr_err("\n");
diff --git a/platform/casablanca/lwis_platform_casablanca.c b/platform/casablanca/lwis_platform_casablanca.c
index e2ce435..5fb952b 100644
--- a/platform/casablanca/lwis_platform_casablanca.c
+++ b/platform/casablanca/lwis_platform_casablanca.c
@@ -82,7 +82,7 @@ static int lwis_iommu_fault_handler(struct iommu_fault *fault, void *param)
 	pr_err("\n");
 	lwis_debug_print_transaction_info(lwis_dev);
 	pr_err("\n");
-	lwis_debug_print_event_states_info(lwis_dev);
+	lwis_debug_print_event_states_info(lwis_dev, /*lwis_event_dump_cnt=*/-1);
 	pr_err("\n");
 	lwis_debug_print_buffer_info(lwis_dev);
 	pr_err("\n");