msm: camera: common: create a common root folder for debugfs

Create common root folder under debugfs root named camera at probe. Add
utility functions to create subdirectories under the common camera root.

CRs-Fixed: 3093049
Change-Id: Ia4cefb5d2263ecabf1b9d70deefa1ee624b04f07
Signed-off-by: Anand Ravi <quic_ananravi@quicinc.com>

drivers/cam_cpas/cam_cpas_hw.c

@@ -2916,8 +2916,11 @@ static int cam_cpas_util_create_debugfs(struct cam_cpas *cpas_core)
 	int rc = 0;
 	struct dentry *dbgfileptr = NULL;
 
-	dbgfileptr = debugfs_create_dir("camera_cpas", NULL);
-	if (!dbgfileptr) {
+	if (!cam_debugfs_available())
+		return 0;
+
+	rc = cam_debugfs_create_subdir("cpas", &dbgfileptr);
+	if (rc) {
 		CAM_ERR(CAM_CPAS,"DebugFS could not create directory!");
 		rc = -ENOENT;
 		goto end;
@@ -3138,7 +3141,6 @@ int cam_cpas_hw_remove(struct cam_hw_intf *cpas_hw_intf)
 	cam_cpas_util_unregister_bus_client(&cpas_core->ahb_bus_client);
 	cam_cpas_util_client_cleanup(cpas_hw);
 	cam_cpas_soc_deinit_resources(&cpas_hw->soc_info);
-	debugfs_remove_recursive(cpas_core->dentry);
 	cpas_core->dentry = NULL;
 	flush_workqueue(cpas_core->work_queue);
 	destroy_workqueue(cpas_core->work_queue);

drivers/cam_cre/cam_cre_hw_mgr/cam_cre_hw_mgr.c

@@ -2888,38 +2888,22 @@ DEFINE_DEBUGFS_ATTRIBUTE(cam_cre_debug_default_clk,
 
 static int cam_cre_create_debug_fs(void)
 {
-	struct dentry *dbgfileptr = NULL;
-	int rc = 0;
-	cre_hw_mgr->dentry = debugfs_create_dir("camera_cre",
-		NULL);
+	if (!cam_debugfs_available())
+		return 0;
 
+	cam_debugfs_create_subdir("cre", &cre_hw_mgr->dentry);
 	if (!cre_hw_mgr->dentry) {
 		CAM_ERR(CAM_CRE, "failed to create dentry");
 		return -ENOMEM;
 	}
 
-	if (!debugfs_create_bool("dump_req_data_enable",
-		0644,
-		cre_hw_mgr->dentry,
-		&cre_hw_mgr->dump_req_data_enable)) {
-		CAM_ERR(CAM_CRE,
-			"failed to create dump_enable_debug");
-		goto err;
-	}
+	debugfs_create_bool("dump_req_data_enable", 0644, cre_hw_mgr->dentry,
+		&cre_hw_mgr->dump_req_data_enable);
 
-	dbgfileptr = debugfs_create_file("cre_debug_clk", 0644,
-		cre_hw_mgr->dentry, NULL, &cam_cre_debug_default_clk);
+	debugfs_create_file("cre_debug_clk", 0644, cre_hw_mgr->dentry,
+		NULL, &cam_cre_debug_default_clk);
 
-	if (IS_ERR(dbgfileptr)) {
-		if (PTR_ERR(dbgfileptr) == -ENODEV)
-			CAM_WARN(CAM_CRE, "DebugFS not enabled in kernel!");
-		else
-			rc = PTR_ERR(dbgfileptr);
-	}
 	return 0;
-err:
-	debugfs_remove_recursive(cre_hw_mgr->dentry);
-	return -ENOMEM;
 }
 
 int cam_cre_hw_mgr_init(struct device_node *of_node, void *hw_mgr,

drivers/cam_icp/icp_hw/icp_hw_mgr/cam_icp_hw_mgr.c

@@ -1925,8 +1925,11 @@ static int cam_icp_hw_mgr_create_debugfs_entry(void)
 	int rc = 0;
 	struct dentry *dbgfileptr = NULL;
 
-	dbgfileptr = debugfs_create_dir("camera_icp", NULL);
-	if (!dbgfileptr) {
+	if (!cam_debugfs_available())
+		return 0;
+
+	rc = cam_debugfs_create_subdir("icp", &dbgfileptr);
+	if (rc) {
 		CAM_ERR(CAM_ICP,"DebugFS could not create directory!");
 		rc = -ENOENT;
 		goto end;
@@ -6613,7 +6616,6 @@ void cam_icp_hw_mgr_deinit(void)
 {
 	int i = 0;
 
-	debugfs_remove_recursive(icp_hw_mgr.dentry);
 	icp_hw_mgr.dentry = NULL;
 	cam_icp_mgr_destroy_wq();
 	cam_icp_mgr_free_devs();

drivers/cam_isp/cam_isp_context.c

@@ -7239,12 +7239,15 @@ static int cam_isp_context_debug_register(void)
 	int rc = 0;
 	struct dentry *dbgfileptr = NULL;
 
-	dbgfileptr = debugfs_create_dir("camera_isp_ctx", NULL);
-	if (!dbgfileptr) {
+	if (!cam_debugfs_available())
+		return 0;
+
+	rc = cam_debugfs_create_subdir("isp_ctx", &dbgfileptr);
+	if (rc) {
 		CAM_ERR(CAM_ISP, "DebugFS could not create directory!");
-		rc = -ENOENT;
-		goto end;
+		return rc;
 	}
+
 	/* Store parent inode for cleanup in caller */
 	isp_ctx_debug.dentry = dbgfileptr;
 
@@ -7255,14 +7258,7 @@ static int cam_isp_context_debug_register(void)
 	debugfs_create_bool("disable_internal_recovery", 0644,
 		isp_ctx_debug.dentry, &isp_ctx_debug.disable_internal_recovery);
 
-	if (IS_ERR(dbgfileptr)) {
-		if (PTR_ERR(dbgfileptr) == -ENODEV)
-			CAM_WARN(CAM_ISP, "DebugFS not enabled in kernel!");
-		else
-			rc = PTR_ERR(dbgfileptr);
-	}
-end:
-	return rc;
+	return 0;
 }
 
 int cam_isp_context_init(struct cam_isp_context *ctx,
@@ -7346,7 +7342,6 @@ int cam_isp_context_deinit(struct cam_isp_context *ctx)
 			__cam_isp_ctx_substate_val_to_type(
 			ctx->substate_activated));
 
-	debugfs_remove_recursive(isp_ctx_debug.dentry);
 	isp_ctx_debug.dentry = NULL;
 	memset(ctx, 0, sizeof(*ctx));
 

drivers/cam_isp/isp_hw_mgr/cam_ife_hw_mgr.c

@@ -13063,8 +13063,11 @@ static int cam_ife_hw_mgr_debug_register(void)
 	int rc = 0;
 	struct dentry *dbgfileptr = NULL;
 
-	dbgfileptr = debugfs_create_dir("camera_ife", NULL);
-	if (!dbgfileptr) {
+	if (!cam_debugfs_available())
+		return 0;
+
+	rc = cam_debugfs_create_subdir("ife", &dbgfileptr);
+	if (rc) {
 		CAM_ERR(CAM_ISP,"DebugFS could not create directory!");
 		rc = -ENOENT;
 		goto end;
@@ -13521,7 +13524,6 @@ void cam_ife_hw_mgr_deinit(void)
 	int i = 0;
 
 	cam_req_mgr_workq_destroy(&g_ife_hw_mgr.workq);
-	debugfs_remove_recursive(g_ife_hw_mgr.debug_cfg.dentry);
 	g_ife_hw_mgr.debug_cfg.dentry = NULL;
 
 	for (i = 0; i < CAM_IFE_CTX_MAX; i++) {

drivers/cam_isp/isp_hw_mgr/cam_tfe_hw_mgr.c

@@ -5732,14 +5732,16 @@ DEFINE_DEBUGFS_ATTRIBUTE(cam_tfe_camif_debug,
 	cam_tfe_get_camif_debug,
 	cam_tfe_set_camif_debug, "%16llu");
 
-#if IS_ENABLED(CONFIG_DEBUG_FS)
 static int cam_tfe_hw_mgr_debug_register(void)
 {
 	int rc = 0;
 	struct dentry *dbgfileptr = NULL;
 
-	dbgfileptr = debugfs_create_dir("camera_tfe", NULL);
-	if (!dbgfileptr) {
+	if (!cam_debugfs_available())
+		goto end;
+
+	rc = cam_debugfs_create_subdir("tfe", &dbgfileptr);
+	if (rc) {
 		CAM_ERR(CAM_ISP,"DebugFS could not create directory!");
 		rc = -ENOENT;
 		goto end;
@@ -5773,14 +5775,6 @@ end:
 	g_tfe_hw_mgr.debug_cfg.enable_recovery = 0;
 	return rc;
 }
-#else
-static inline int cam_tfe_hw_mgr_debug_register(void)
-{
-	g_tfe_hw_mgr.debug_cfg.enable_recovery = 0;
-	CAM_WARN(CAM_ISP, "DebugFS not enabled in kernel");
-	return 0;
-}
-#endif
 
 static void cam_req_mgr_process_tfe_worker(struct work_struct *w)
 {
@@ -5995,7 +5989,6 @@ void cam_tfe_hw_mgr_deinit(void)
 	int i = 0;
 
 	cam_req_mgr_workq_destroy(&g_tfe_hw_mgr.workq);
-	debugfs_remove_recursive(g_tfe_hw_mgr.debug_cfg.dentry);
 	g_tfe_hw_mgr.debug_cfg.dentry = NULL;
 
 	for (i = 0; i < CAM_TFE_CTX_MAX; i++) {

drivers/cam_jpeg/jpeg_hw/cam_jpeg_hw_mgr.c

@@ -2127,28 +2127,23 @@ static int cam_jpeg_mgr_create_debugfs_entry(void)
 	int rc = 0;
 	struct dentry *dbgfileptr = NULL;
 
-	dbgfileptr = debugfs_create_dir("camera_jpeg", NULL);
-	if (!dbgfileptr) {
+	if (!cam_debugfs_available())
+		return 0;
+
+	rc = cam_debugfs_create_subdir("jpeg", &dbgfileptr);
+	if (rc) {
 		CAM_ERR(CAM_JPEG, "DebugFS could not create directory!");
-		rc = -ENOENT;
-		goto err;
+		return rc;
 	}
 	/* Store parent inode for cleanup in caller */
 	g_jpeg_hw_mgr.dentry = dbgfileptr;
 
-	dbgfileptr = debugfs_create_file("camnoc_misr_test", 0644,
-		g_jpeg_hw_mgr.dentry, NULL, &camnoc_misr_test);
+	debugfs_create_file("camnoc_misr_test", 0644, g_jpeg_hw_mgr.dentry,
+		NULL, &camnoc_misr_test);
 
-	dbgfileptr = debugfs_create_file("bug_on_misr_mismatch", 0644,
-		g_jpeg_hw_mgr.dentry, NULL, &bug_on_misr_mismatch);
+	debugfs_create_file("bug_on_misr_mismatch", 0644, g_jpeg_hw_mgr.dentry,
+		NULL, &bug_on_misr_mismatch);
 
-	if (IS_ERR(dbgfileptr)) {
-		if (PTR_ERR(dbgfileptr) == -ENODEV)
-			CAM_WARN(CAM_JPEG, "DebugFS not enabled in kernel!");
-		else
-			rc = PTR_ERR(dbgfileptr);
-	}
-err:
 	return rc;
 }
 

drivers/cam_lrme/lrme_hw_mgr/cam_lrme_hw_mgr.c

@@ -1022,27 +1022,21 @@ static int cam_lrme_mgr_create_debugfs_entry(void)
 	int rc = 0;
 	struct dentry *dbgfileptr = NULL;
 
-	dbgfileptr = debugfs_create_dir("camera_lrme", NULL);
-	if (!dbgfileptr) {
+	if (!cam_debugfs_available())
+		return 0;
+
+	rc = cam_debugfs_create_subdir("lrme", &dbgfileptr);
+	if (rc) {
 		CAM_ERR(CAM_ISP,"DebugFS could not create directory!");
-		rc = -ENOENT;
-		goto err;
+		return -ENOENT;
 	}
 	/* Store parent inode for cleanup in caller */
 	g_lrme_hw_mgr.debugfs_entry.dentry = dbgfileptr;
 
-	dbgfileptr = debugfs_create_bool("dump_register", 0644,
-		g_lrme_hw_mgr.debugfs_entry.dentry,
+	debugfs_create_bool("dump_register", 0644, g_lrme_hw_mgr.debugfs_entry.dentry,
 		&g_lrme_hw_mgr.debugfs_entry.dump_register);
-	if (IS_ERR(dbgfileptr)) {
-		if (PTR_ERR(dbgfileptr) == -ENODEV)
-			CAM_WARN(CAM_LRME, "DebugFS not enabled in kernel!");
-		else
-			rc = PTR_ERR(dbgfileptr);
-	}
 
-err:
-	return rc;
+	return 0;
 }
 
 static void cam_req_mgr_process_workq_cam_lrme_device_submit_worker(
@@ -1149,7 +1143,6 @@ int cam_lrme_mgr_deregister_device(int device_index)
 int cam_lrme_hw_mgr_deinit(void)
 {
 	mutex_destroy(&g_lrme_hw_mgr.hw_mgr_mutex);
-	debugfs_remove_recursive(g_lrme_hw_mgr.debugfs_entry.dentry);
 	memset(&g_lrme_hw_mgr, 0x0, sizeof(g_lrme_hw_mgr));
 
 	return 0;

drivers/cam_ope/ope_hw_mgr/cam_ope_hw_mgr.c

@@ -3901,36 +3901,24 @@ cmd_work_failed:
 
 static int cam_ope_create_debug_fs(void)
 {
-	ope_hw_mgr->dentry = debugfs_create_dir("camera_ope",
-		NULL);
+	int rc;
 
-	if (!ope_hw_mgr->dentry) {
+	if (!cam_debugfs_available())
+		return 0;
+
+	rc = cam_debugfs_create_subdir("ope", &ope_hw_mgr->dentry);
+	if (rc) {
 		CAM_ERR(CAM_OPE, "failed to create dentry");
-		return -ENOMEM;
+		return rc;
 	}
 
-	if (!debugfs_create_bool("frame_dump_enable",
-		0644,
-		ope_hw_mgr->dentry,
-		&ope_hw_mgr->frame_dump_enable)) {
-		CAM_ERR(CAM_OPE,
-			"failed to create dump_enable_debug");
-		goto err;
-	}
+	debugfs_create_bool("frame_dump_enable", 0644, ope_hw_mgr->dentry,
+		&ope_hw_mgr->frame_dump_enable);
 
-	if (!debugfs_create_bool("dump_req_data_enable",
-		0644,
-		ope_hw_mgr->dentry,
-		&ope_hw_mgr->dump_req_data_enable)) {
-		CAM_ERR(CAM_OPE,
-			"failed to create dump_enable_debug");
-		goto err;
-	}
+	debugfs_create_bool("dump_req_data_enable", 0644, ope_hw_mgr->dentry,
+		&ope_hw_mgr->dump_req_data_enable);
 
 	return 0;
-err:
-	debugfs_remove_recursive(ope_hw_mgr->dentry);
-	return -ENOMEM;
 }
 
 

drivers/cam_req_mgr/cam_mem_mgr.c

@@ -30,6 +30,16 @@
 static struct cam_mem_table tbl;
 static atomic_t cam_mem_mgr_state = ATOMIC_INIT(CAM_MEM_MGR_UNINITIALIZED);
 
+/* cam_mem_mgr_debug - global struct to keep track of debug settings for mem mgr
+ *
+ * @dentry               : Directory entry to the mem mgr root folder
+ * @alloc_profile_enable : Whether to enable alloc profiling
+ */
+static struct {
+	struct dentry *dentry;
+	bool alloc_profile_enable;
+} g_cam_mem_mgr_debug;
+
 #if IS_REACHABLE(CONFIG_DMABUF_HEAPS)
 static void cam_mem_mgr_put_dma_heaps(void);
 static int cam_mem_mgr_get_dma_heaps(void);
@@ -65,7 +75,7 @@ static unsigned long cam_mem_mgr_mini_dump_cb(void *dst, unsigned long len)
 	md = (struct cam_mem_table_mini_dump *)dst;
 	memcpy(md->bufq, tbl.bufq, CAM_MEM_BUFQ_MAX * sizeof(struct cam_mem_buf_queue));
 	md->dbg_buf_idx = tbl.dbg_buf_idx;
-	md->alloc_profile_enable = tbl.alloc_profile_enable;
+	md->alloc_profile_enable = g_cam_mem_mgr_debug.alloc_profile_enable;
 	md->force_cache_allocs = tbl.force_cache_allocs;
 	md->need_shared_buffer_padding = tbl.need_shared_buffer_padding;
 	return sizeof(*md);
@@ -170,17 +180,20 @@ static int cam_mem_mgr_create_debug_fs(void)
 	int rc = 0;
 	struct dentry *dbgfileptr = NULL;
 
-	dbgfileptr = debugfs_create_dir("camera_memmgr", NULL);
-	if (!dbgfileptr) {
-		CAM_ERR(CAM_MEM,"DebugFS could not create directory!");
+	if (!cam_debugfs_available() || g_cam_mem_mgr_debug.dentry)
+		return 0;
+
+	rc = cam_debugfs_create_subdir("memmgr", &dbgfileptr);
+	if (rc) {
+		CAM_ERR(CAM_MEM, "DebugFS could not create directory!");
 		rc = -ENOENT;
 		goto end;
 	}
-	/* Store parent inode for cleanup in caller */
-	tbl.dentry = dbgfileptr;
 
-	debugfs_create_bool("alloc_profile_enable", 0644,
-		tbl.dentry, &tbl.alloc_profile_enable);
+	g_cam_mem_mgr_debug.dentry = dbgfileptr;
+
+	debugfs_create_bool("alloc_profile_enable", 0644, g_cam_mem_mgr_debug.dentry,
+		&g_cam_mem_mgr_debug.alloc_profile_enable);
 end:
 	return rc;
 }
@@ -556,7 +569,7 @@ static int cam_mem_util_get_dma_buf(size_t len,
 		return -EINVAL;
 	}
 
-	if (tbl.alloc_profile_enable)
+	if (g_cam_mem_mgr_debug.alloc_profile_enable)
 		CAM_GET_TIMESTAMP(ts1);
 
 	if ((cam_flags & CAM_MEM_FLAG_CACHE) ||
@@ -667,7 +680,7 @@ static int cam_mem_util_get_dma_buf(size_t len,
 
 	CAM_DBG(CAM_MEM, "Allocate success, len=%zu, *buf=%pK, i_ino=%lu", len, *buf, *i_ino);
 
-	if (tbl.alloc_profile_enable) {
+	if (g_cam_mem_mgr_debug.alloc_profile_enable) {
 		CAM_GET_TIMESTAMP(ts2);
 		CAM_GET_TIMESTAMP_DIFF_IN_MICRO(ts1, ts2, microsec);
 		trace_cam_log_event("IONAllocProfile", "size and time in micro",
@@ -696,7 +709,7 @@ static int cam_mem_util_get_dma_buf(size_t len,
 		return -EINVAL;
 	}
 
-	if (tbl.alloc_profile_enable)
+	if (g_cam_mem_mgr_debug.alloc_profile_enable)
 		CAM_GET_TIMESTAMP(ts1);
 
 	if ((cam_flags & CAM_MEM_FLAG_PROTECTED_MODE) &&
@@ -726,7 +739,7 @@ static int cam_mem_util_get_dma_buf(size_t len,
 
 	*i_ino = file_inode((*buf)->file)->i_ino;
 
-	if (tbl.alloc_profile_enable) {
+	if (g_cam_mem_mgr_debug.alloc_profile_enable) {
 		CAM_GET_TIMESTAMP(ts2);
 		CAM_GET_TIMESTAMP_DIFF_IN_MICRO(ts1, ts2, microsec);
 		trace_cam_log_event("IONAllocProfile", "size and time in micro",
@@ -1318,7 +1331,6 @@ void cam_mem_mgr_deinit(void)
 {
 	atomic_set(&cam_mem_mgr_state, CAM_MEM_MGR_UNINITIALIZED);
 	cam_mem_mgr_cleanup_table();
-	debugfs_remove_recursive(tbl.dentry);
 	mutex_lock(&tbl.m_lock);
 	bitmap_zero(tbl.bitmap, tbl.bits);
 	kfree(tbl.bitmap);

drivers/cam_req_mgr/cam_mem_mgr.h

@@ -84,8 +84,6 @@ struct cam_mem_buf_queue {
  * @bitmap: bitmap of the mem mgr utility
  * @bits: max bits of the utility
  * @bufq: array of buffers
- * @dentry: Debugfs entry
- * @alloc_profile_enable: Whether to enable alloc profiling
  * @dbg_buf_idx: debug buffer index to get usecases info
  * @force_cache_allocs: Force all internal buffer allocations with cache
  * @need_shared_buffer_padding: Whether padding is needed for shared buffer
@@ -101,8 +99,6 @@ struct cam_mem_table {
 	void *bitmap;
 	size_t bits;
 	struct cam_mem_buf_queue bufq[CAM_MEM_BUFQ_MAX];
-	struct dentry *dentry;
-	bool alloc_profile_enable;
 	size_t dbg_buf_idx;
 	bool force_cache_allocs;
 	bool need_shared_buffer_padding;

drivers/cam_req_mgr/cam_req_mgr_debug.c

@@ -117,8 +117,11 @@ int cam_req_mgr_debug_register(struct cam_req_mgr_core_device *core_dev)
 	int rc = 0;
 	struct dentry *dbgfileptr = NULL;
 
-	dbgfileptr = debugfs_create_dir("cam_req_mgr", NULL);
-	if (!dbgfileptr) {
+	if (!cam_debugfs_available())
+		return 0;
+
+	rc = cam_debugfs_create_subdir("req_mgr", &dbgfileptr);
+	if (rc) {
 		CAM_ERR(CAM_MEM,"DebugFS could not create directory!");
 		rc = -ENOENT;
 		goto end;
@@ -140,7 +143,6 @@ end:
 
 int cam_req_mgr_debug_unregister(void)
 {
-	debugfs_remove_recursive(debugfs_root);
 	debugfs_root = NULL;
 	return 0;
 }

drivers/cam_sensor_module/cam_cci/cam_cci_dev.c

@@ -405,44 +405,31 @@ DEFINE_DEBUGFS_ATTRIBUTE(cam_cci_debug,
 
 static int cam_cci_create_debugfs_entry(struct cci_device *cci_dev)
 {
-	int rc = 0;
+	int rc = 0, idx;
 	struct dentry *dbgfileptr = NULL;
+	static char * const filename[] = { "en_dump_cci0", "en_dump_cci1", "en_dump_cci2"};
+
+	if (!cam_debugfs_available())
+		return 0;
 
 	if (!debugfs_root) {
-		dbgfileptr = debugfs_create_dir("cam_cci", NULL);
-		if (!dbgfileptr) {
+		rc = cam_debugfs_create_subdir("cci", &dbgfileptr);
+		if (rc) {
 			CAM_ERR(CAM_CCI, "debugfs directory creation fail");
-			rc = -ENOENT;
-			goto end;
+			return rc;
 		}
 		debugfs_root = dbgfileptr;
 	}
 
-	if (cci_dev->soc_info.index == 0) {
-		dbgfileptr = debugfs_create_file("en_dump_cci0", 0644,
-			debugfs_root, cci_dev, &cam_cci_debug);
-		if (IS_ERR(dbgfileptr)) {
-			if (PTR_ERR(dbgfileptr) == -ENODEV)
-				CAM_WARN(CAM_CCI, "DebugFS not enabled");
-			else {
-				rc = PTR_ERR(dbgfileptr);
-				goto end;
-			}
-		}
-	} else {
-		dbgfileptr = debugfs_create_file("en_dump_cci1", 0644,
-			debugfs_root, cci_dev, &cam_cci_debug);
-		if (IS_ERR(dbgfileptr)) {
-			if (PTR_ERR(dbgfileptr) == -ENODEV)
-				CAM_WARN(CAM_CCI, "DebugFS not enabled");
-			else {
-				rc = PTR_ERR(dbgfileptr);
-				goto end;
-			}
-		}
+	idx = cci_dev->soc_info.index;
+	if (idx >= ARRAY_SIZE(filename)) {
+		CAM_ERR(CAM_CCI, "cci-dev %d invalid", idx);
+		return -ENODEV;
 	}
-end:
-	return rc;
+
+	debugfs_create_file(filename[idx], 0644, debugfs_root, cci_dev, &cam_cci_debug);
+
+	return 0;
 }
 
 static int cam_cci_component_bind(struct device *dev,
@@ -547,7 +534,6 @@ static void cam_cci_component_unbind(struct device *dev,
 		v4l2_get_subdevdata(subdev);
 
 	cam_cpas_unregister_client(cci_dev->cpas_handle);
-	debugfs_remove_recursive(debugfs_root);
 	debugfs_root = NULL;
 	cam_cci_soc_remove(pdev, cci_dev);
 	rc = cam_unregister_subdev(&(cci_dev->v4l2_dev_str));

drivers/cam_sensor_module/cam_csiphy/cam_csiphy_dev.c

@@ -55,13 +55,16 @@ static int cam_csiphy_debug_register(struct csiphy_device *csiphy_dev)
 		return -EINVAL;
 	}
 
+	if (!cam_debugfs_available())
+		return 0;
+
 	if (!root_dentry) {
-		root_dentry = debugfs_create_dir("camera_csiphy", NULL);
-		if (IS_ERR(root_dentry)) {
-			CAM_ERR(CAM_CSIPHY, "Debugfs could not create root directory. rc: %ld",
-				root_dentry);
+		if (cam_debugfs_create_subdir("csiphy", &dbgfileptr)) {
+			CAM_ERR(CAM_CSIPHY,
+				"Debugfs could not create directory!");
 			return -ENOENT;
 		}
+		root_dentry = dbgfileptr;
 	}
 
 	/* Create the CSIPHY directory for this csiphy */
@@ -88,7 +91,6 @@ static int cam_csiphy_debug_register(struct csiphy_device *csiphy_dev)
 
 static void cam_csiphy_debug_unregister(void)
 {
-	debugfs_remove_recursive(root_dentry);
 	root_dentry = NULL;
 }
 

drivers/cam_smmu/cam_smmu_api.c

@@ -4450,8 +4450,11 @@ static int cam_smmu_create_debug_fs(void)
 	int rc = 0;
 	struct dentry *dbgfileptr = NULL;
 
-	dbgfileptr = debugfs_create_dir("camera_smmu", NULL);
-	if (!dbgfileptr) {
+	if (!cam_debugfs_available())
+		return 0;
+
+	rc = cam_debugfs_create_subdir("smmu", &dbgfileptr);
+	if (rc) {
 		CAM_ERR(CAM_SMMU,"DebugFS could not create directory!");
 		rc = -ENOENT;
 		goto end;
@@ -4586,7 +4589,6 @@ static void cam_smmu_component_unbind(struct device *dev,
 	}
 
 	cam_smmu_release_cb(pdev);
-	debugfs_remove_recursive(iommu_cb_set.dentry);
 	iommu_cb_set.dentry = NULL;
 }
 

drivers/cam_sync/cam_sync.c

@@ -1068,8 +1068,11 @@ static int cam_sync_create_debugfs(void)
 	int rc = 0;
 	struct dentry *dbgfileptr = NULL;
 
-	dbgfileptr = debugfs_create_dir("camera_sync", NULL);
-	if (!dbgfileptr) {
+	if (!cam_debugfs_available())
+		return 0;
+
+	rc = cam_debugfs_create_subdir("sync", &dbgfileptr);
+	if (rc) {
 		CAM_ERR(CAM_SYNC,"DebugFS could not create directory!");
 		rc = -ENOENT;
 		goto end;
@@ -1263,7 +1266,6 @@ static void cam_sync_component_unbind(struct device *dev,
 #endif
 	video_unregister_device(sync_dev->vdev);
 	video_device_release(sync_dev->vdev);
-	debugfs_remove_recursive(sync_dev->dentry);
 	sync_dev->dentry = NULL;
 
 	for (i = 0; i < CAM_SYNC_MAX_OBJS; i++)

drivers/cam_utils/cam_debug_util.c

@@ -1,11 +1,12 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * Copyright (c) 2017-2021, The Linux Foundataion. All rights reserved.
+ * Copyright (c) 2017-2021, The Linux Foundation. All rights reserved.
  */
 
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/module.h>
+#include <linux/debugfs.h>
 #include "cam_trace.h"
 
 #include "cam_debug_util.h"
@@ -22,6 +23,85 @@ module_param(debug_priority, uint, 0644);
 
 struct camera_debug_settings cam_debug;
 
+struct dentry *cam_debugfs_root;
+
+void cam_debugfs_init(void)
+{
+	struct dentry *tmp;
+
+	if (!cam_debugfs_available()) {
+		cam_debugfs_root = NULL;
+		CAM_DBG(CAM_UTIL, "debugfs not available");
+		return;
+	}
+
+	if (cam_debugfs_root) {
+		CAM_WARN(CAM_UTIL, "already created debugfs root");
+		return;
+	}
+
+	tmp = debugfs_create_dir("camera", NULL);
+	if (IS_ERR_VALUE(tmp)) {
+		CAM_ERR(CAM_UTIL, "failed to create debugfs root folder (rc=%d)", PTR_ERR(tmp));
+		return;
+	}
+
+	cam_debugfs_root = tmp;
+	CAM_DBG(CAM_UTIL, "successfully created debugfs root");
+}
+
+void cam_debugfs_deinit(void)
+{
+	if (!cam_debugfs_available())
+		return;
+
+	debugfs_remove_recursive(cam_debugfs_root);
+	cam_debugfs_root = NULL;
+}
+
+int cam_debugfs_create_subdir(const char *name, struct dentry **subdir)
+{
+	struct dentry *tmp;
+
+	if (!cam_debugfs_root) {
+		CAM_WARN(CAM_UTIL, "debugfs root not created");
+		*subdir = NULL;
+		return -ENODEV;
+	}
+
+	if (!subdir) {
+		CAM_ERR(CAM_UTIL, "invalid subdir pointer %pK", subdir);
+		return -EINVAL;
+	}
+
+	tmp = debugfs_create_dir(name, cam_debugfs_root);
+	if (IS_ERR_VALUE(tmp)) {
+		CAM_ERR(CAM_UTIL, "failed to create debugfs subdir (name=%s, rc=%d)", name,
+			PTR_ERR(tmp));
+		return PTR_ERR(tmp);
+	}
+
+	*subdir = tmp;
+	return 0;
+}
+
+int cam_debugfs_lookup_subdir(const char *name, struct dentry **subdir)
+{
+	if (!cam_debugfs_root) {
+		CAM_WARN(CAM_UTIL, "debugfs root not created");
+		*subdir = NULL;
+		return -ENODEV;
+	}
+
+	if (!subdir) {
+		CAM_ERR(CAM_UTIL, "invalid subdir pointer %pK", subdir);
+		return -EINVAL;
+	}
+
+	*subdir = debugfs_lookup(name, cam_debugfs_root);
+	return (*subdir) ? 0 : -ENOENT;
+}
+
 const struct camera_debug_settings *cam_debug_get_settings()
 {
 	return &cam_debug;

drivers/cam_utils/cam_debug_util.h

@@ -360,4 +360,59 @@ const struct camera_debug_settings *cam_debug_get_settings(void);
 ssize_t cam_debug_sysfs_node_store(struct device *dev,
 		struct device_attribute *attr, const char *buf, size_t count);
 
+/**
+ * cam_debugfs_init()
+ *
+ * @brief: create camera debugfs root folder
+ */
+void cam_debugfs_init(void);
+
+/**
+ * cam_debugfs_deinit()
+ *
+ * @brief: remove camera debugfs root folder
+ */
+void cam_debugfs_deinit(void);
+
+/**
+ * cam_debugfs_create_subdir()
+ *
+ * @brief:  create a directory within the camera debugfs root folder
+ *
+ * @name:   name of the directory
+ * @subdir: pointer to the newly created directory entry
+ *
+ * @return: 0 on success, negative on failure
+ */
+int cam_debugfs_create_subdir(const char *name, struct dentry **subdir);
+
+/**
+ * cam_debugfs_lookup_subdir()
+ *
+ * @brief:  lookup a directory within the camera debugfs root folder
+ *
+ * @name:   name of the directory
+ * @subdir: pointer to the successfully found directory entry
+ *
+ * @return: 0 on success, negative on failure
+ */
+int cam_debugfs_lookup_subdir(const char *name, struct dentry **subdir);
+
+/**
+ * cam_debugfs_available()
+ *
+ * @brief:  Check if debugfs is enabled for camera. Use this function before creating any
+ *          debugfs entries.
+ *
+ * @return: true if enabled, false otherwise
+ */
+static inline bool cam_debugfs_available(void)
+{
+	#if defined(CONFIG_DEBUG_FS)
+		return true;
+	#else
+		return false;
+	#endif
+}
+
 #endif /* _CAM_DEBUG_UTIL_H_ */

drivers/cam_utils/cam_soc_util.c

@@ -22,6 +22,8 @@
 #define CAM_SS_START_PRESIL 0x08c00000
 #define CAM_SS_START        0x0ac00000
 
+#define CAM_CLK_DIRNAME "clk"
+
 static uint skip_mmrm_set_rate;
 module_param(skip_mmrm_set_rate, uint, 0644);
 
@@ -684,23 +686,32 @@ DEFINE_SIMPLE_ATTRIBUTE(cam_soc_util_clk_lvl_control,
  */
 static int cam_soc_util_create_clk_lvl_debugfs(struct cam_hw_soc_info *soc_info)
 {
-	char debugfs_dir_name[64];
 	int rc = 0;
-	struct dentry *dbgfileptr = NULL;
+	struct dentry *dbgfileptr = NULL, *clkdirptr = NULL;
+
+	if (!cam_debugfs_available())
+		return 0;
 
 	if (soc_info->dentry) {
-		CAM_DBG(CAM_UTIL, "Debugfs entry for %s already exist",
+		CAM_DBG(CAM_UTIL, "Debugfs entry for %s already exists",
 			soc_info->dev_name);
 		goto end;
 	}
 
-	memset(debugfs_dir_name, 0, sizeof(debugfs_dir_name));
-	strlcat(debugfs_dir_name, "clk_dir_", sizeof(debugfs_dir_name));
-	strlcat(debugfs_dir_name, soc_info->dev_name, sizeof(debugfs_dir_name));
+	rc = cam_debugfs_lookup_subdir(CAM_CLK_DIRNAME, &clkdirptr);
+	if (rc) {
+		rc = cam_debugfs_create_subdir(CAM_CLK_DIRNAME, &clkdirptr);
+		if (rc) {
+			CAM_ERR(CAM_UTIL, "DebugFS could not create clk directory!");
+			rc = -ENOENT;
+			goto end;
+		}
+	}
 
-	dbgfileptr = debugfs_create_dir(debugfs_dir_name, NULL);
-	if (!dbgfileptr) {
-		CAM_ERR(CAM_UTIL,"DebugFS could not create directory!");
+	dbgfileptr = debugfs_create_dir(soc_info->dev_name, clkdirptr);
+	if (IS_ERR_OR_NULL(dbgfileptr)) {
+		CAM_ERR(CAM_UTIL, "DebugFS could not create directory for dev:%s!",
+			soc_info->dev_name);
 		rc = -ENOENT;
 		goto end;
 	}
@@ -711,32 +722,11 @@ static int cam_soc_util_create_clk_lvl_debugfs(struct cam_hw_soc_info *soc_info)
 		soc_info->dentry, soc_info, &cam_soc_util_clk_lvl_options);
 	dbgfileptr = debugfs_create_file("clk_lvl_control", 0644,
 		soc_info->dentry, soc_info, &cam_soc_util_clk_lvl_control);
-	if (IS_ERR(dbgfileptr)) {
-		if (PTR_ERR(dbgfileptr) == -ENODEV)
-			CAM_WARN(CAM_UTIL, "DebugFS not enabled in kernel!");
-		else
-			rc = PTR_ERR(dbgfileptr);
-	}
+	rc = PTR_ERR_OR_ZERO(dbgfileptr);
 end:
 	return rc;
 }
 
-/**
- * cam_soc_util_remove_clk_lvl_debugfs()
- *
- * @brief:      Removes the debugfs files used to view/control
- *              device clk rates
- *
- * @soc_info:   Device soc information
- *
- */
-static void cam_soc_util_remove_clk_lvl_debugfs(
-	struct cam_hw_soc_info *soc_info)
-{
-	debugfs_remove_recursive(soc_info->dentry);
-	soc_info->dentry = NULL;
-}
-
 int cam_soc_util_get_level_from_string(const char *string,
 	enum cam_vote_level *level)
 {
@@ -2836,8 +2826,7 @@ int cam_soc_util_release_platform_resource(struct cam_hw_soc_info *soc_info)
 	/* release for gpio */
 	cam_soc_util_request_gpio_table(soc_info, false);
 
-	if (soc_info->clk_control_enable)
-		cam_soc_util_remove_clk_lvl_debugfs(soc_info);
+	soc_info->dentry = NULL;
 
 	return 0;
 }

drivers/camera_main.c

@@ -288,6 +288,8 @@ static int camera_init(void)
 	if (rc)
 		goto end_init;
 
+	cam_debugfs_init();
+
 	/* For Probing all available submodules */
 	for (i = 0; i < ARRAY_SIZE(submodule_table); i++) {
 		num_inits = submodule_table[i].num_component;
@@ -316,6 +318,7 @@ end_init:
 static void camera_exit(void)
 {
 	__camera_exit(ARRAY_SIZE(submodule_table), 0);
+	cam_debugfs_deinit();
 
 	CAM_INFO(CAM_UTIL, "Spectra camera driver exited!");
 }