usb: dwc2: move debugfs code to a separate file

Prepare to add more debug code. Moreover, don't save dentry * for
each file in struct dwc2_hsotg as clean up is done with
debugfs_remove_recursive(). s3c_hsotg_delete_debug() is removed
altogether for the same reason.
Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc2/Makefile

@@ -13,6 +13,10 @@ ifneq ($(filter y,$(CONFIG_USB_DWC2_PERIPHERAL) $(CONFIG_USB_DWC2_DUAL_ROLE)),)
 	dwc2-y       			+= gadget.o
 endif
 
+ifneq ($(CONFIG_DEBUG_FS),)
+	dwc2-y				+= debugfs.o
+endif
+
 # NOTE: The previous s3c-hsotg peripheral mode only driver has been moved to
 # this location and renamed gadget.c. When building for dynamically linked
 # modules, dwc2.ko will get built for host mode, peripheral mode, and dual-role

drivers/usb/dwc2/core.h

@@ -615,9 +615,6 @@ struct dwc2_hsotg {
 	enum dwc2_lx_state lx_state;
 
 	struct dentry *debug_root;
-	struct dentry *debug_file;
-	struct dentry *debug_testmode;
-	struct dentry *debug_fifo;
 
 	/* DWC OTG HW Release versions */
 #define DWC2_CORE_REV_2_71a	0x4f54271a
@@ -1005,6 +1002,7 @@ extern void s3c_hsotg_core_init_disconnected(struct dwc2_hsotg *dwc2,
 		bool reset);
 extern void s3c_hsotg_core_connect(struct dwc2_hsotg *hsotg);
 extern void s3c_hsotg_disconnect(struct dwc2_hsotg *dwc2);
+extern int s3c_hsotg_set_test_mode(struct dwc2_hsotg *hsotg, int testmode);
 #else
 static inline int s3c_hsotg_remove(struct dwc2_hsotg *dwc2)
 { return 0; }
@@ -1018,6 +1016,9 @@ static inline void s3c_hsotg_core_init_disconnected(struct dwc2_hsotg *dwc2,
 		bool reset) {}
 static inline void s3c_hsotg_core_connect(struct dwc2_hsotg *hsotg) {}
 static inline void s3c_hsotg_disconnect(struct dwc2_hsotg *dwc2) {}
+static inline int s3c_hsotg_set_test_mode(struct dwc2_hsotg *hsotg,
+							int testmode)
+{ return 0; }
 #endif
 
 #if IS_ENABLED(CONFIG_USB_DWC2_HOST) || IS_ENABLED(CONFIG_USB_DWC2_DUAL_ROLE)

drivers/usb/dwc2/debug.h

+/**
+ * debug.h - Designware USB2 DRD controller debug header
+ *
+ * Copyright (C) 2015 Intel Corporation
+ * Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2  of
+ * the License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include "core.h"
+
+#ifdef CONFIG_DEBUG_FS
+extern int dwc2_debugfs_init(struct dwc2_hsotg *);
+extern void dwc2_debugfs_exit(struct dwc2_hsotg *);
+#else
+static inline int dwc2_debugfs_init(struct dwc2_hsotg *hsotg)
+{  return 0;  }
+static inline void dwc2_debugfs_exit(struct dwc2_hsotg *hsotg)
+{  }
+#endif

drivers/usb/dwc2/platform.c

@@ -47,6 +47,7 @@
 
 #include "core.h"
 #include "hcd.h"
+#include "debug.h"
 
 static const char dwc2_driver_name[] = "dwc2";
 
@@ -121,6 +122,7 @@ static int dwc2_driver_remove(struct platform_device *dev)
 {
 	struct dwc2_hsotg *hsotg = platform_get_drvdata(dev);
 
+	dwc2_debugfs_exit(hsotg);
 	if (hsotg->hcd_enabled)
 		dwc2_hcd_remove(hsotg);
 	if (hsotg->gadget_enabled)
@@ -256,6 +258,8 @@ static int dwc2_driver_probe(struct platform_device *dev)
 
 	platform_set_drvdata(dev, hsotg);
 
+	dwc2_debugfs_init(hsotg);
+
 	return retval;
 }