usb-debugfs.patch

---
 drivers/usb/chipidea/ci.h    |    2 -
 drivers/usb/chipidea/core.c  |    4 --
 drivers/usb/chipidea/debug.c |   56 ++++++++----------------------
 drivers/usb/core/usb.c       |   26 ++------------
 drivers/usb/dwc2/debugfs.c   |   78 ++++++++-----------------------------------
 drivers/usb/dwc3/debugfs.c   |   33 +++---------------
 drivers/usb/host/ehci-dbg.c  |   30 ++++------------
 drivers/usb/mon/mon_text.c   |   37 +++-----------------
 8 files changed, 60 insertions(+), 206 deletions(-)

--- a/drivers/usb/chipidea/ci.h
+++ b/drivers/usb/chipidea/ci.h
@@ -450,7 +450,7 @@ void hw_phymode_configure(struct ci_hdrc
 
 void ci_platform_configure(struct ci_hdrc *ci);
 
-int dbg_create_files(struct ci_hdrc *ci);
+void dbg_create_files(struct ci_hdrc *ci);
 
 void dbg_remove_files(struct ci_hdrc *ci);
 #endif	/* __DRIVERS_USB_CHIPIDEA_CI_H */
--- a/drivers/usb/chipidea/core.c
+++ b/drivers/usb/chipidea/core.c
@@ -1062,9 +1062,7 @@ static int ci_hdrc_probe(struct platform
 		ci_hdrc_otg_fsm_start(ci);
 
 	device_set_wakeup_capable(&pdev->dev, true);
-	ret = dbg_create_files(ci);
-	if (ret)
-		goto stop;
+	dbg_create_files(ci);
 
 	ret = sysfs_create_group(&dev->kobj, &ci_attr_group);
 	if (ret)
--- a/drivers/usb/chipidea/debug.c
+++ b/drivers/usb/chipidea/debug.c
@@ -340,54 +340,28 @@ DEFINE_SHOW_ATTRIBUTE(ci_registers);
  *
  * This function returns an error code
  */
-int dbg_create_files(struct ci_hdrc *ci)
+void dbg_create_files(struct ci_hdrc *ci)
 {
-	struct dentry *dent;
-
 	ci->debugfs = debugfs_create_dir(dev_name(ci->dev), NULL);
-	if (!ci->debugfs)
-		return -ENOMEM;
-
-	dent = debugfs_create_file("device", S_IRUGO, ci->debugfs, ci,
-				   &ci_device_fops);
-	if (!dent)
-		goto err;
-
-	dent = debugfs_create_file("port_test", S_IRUGO | S_IWUSR, ci->debugfs,
-				   ci, &ci_port_test_fops);
-	if (!dent)
-		goto err;
 
-	dent = debugfs_create_file("qheads", S_IRUGO, ci->debugfs, ci,
-				   &ci_qheads_fops);
-	if (!dent)
-		goto err;
-
-	dent = debugfs_create_file("requests", S_IRUGO, ci->debugfs, ci,
-				   &ci_requests_fops);
-	if (!dent)
-		goto err;
+	debugfs_create_file("device", S_IRUGO, ci->debugfs, ci,
+			    &ci_device_fops);
+	debugfs_create_file("port_test", S_IRUGO | S_IWUSR, ci->debugfs, ci,
+			    &ci_port_test_fops);
+	debugfs_create_file("qheads", S_IRUGO, ci->debugfs, ci,
+			    &ci_qheads_fops);
+	debugfs_create_file("requests", S_IRUGO, ci->debugfs, ci,
+			    &ci_requests_fops);
 
 	if (ci_otg_is_fsm_mode(ci)) {
-		dent = debugfs_create_file("otg", S_IRUGO, ci->debugfs, ci,
-					&ci_otg_fops);
-		if (!dent)
-			goto err;
+		debugfs_create_file("otg", S_IRUGO, ci->debugfs, ci,
+				    &ci_otg_fops);
 	}
 
-	dent = debugfs_create_file("role", S_IRUGO | S_IWUSR, ci->debugfs, ci,
-				   &ci_role_fops);
-	if (!dent)
-		goto err;
-
-	dent = debugfs_create_file("registers", S_IRUGO, ci->debugfs, ci,
-				&ci_registers_fops);
-
-	if (dent)
-		return 0;
-err:
-	debugfs_remove_recursive(ci->debugfs);
-	return -ENOMEM;
+	debugfs_create_file("role", S_IRUGO | S_IWUSR, ci->debugfs, ci,
+			    &ci_role_fops);
+	debugfs_create_file("registers", S_IRUGO, ci->debugfs, ci,
+			    &ci_registers_fops);
 }
 
 /**
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -1167,30 +1167,16 @@ static struct notifier_block usb_bus_nb
 struct dentry *usb_debug_root;
 EXPORT_SYMBOL_GPL(usb_debug_root);
 
-static struct dentry *usb_debug_devices;
-
-static int usb_debugfs_init(void)
+static void usb_debugfs_init(void)
 {
 	usb_debug_root = debugfs_create_dir("usb", NULL);
-	if (!usb_debug_root)
-		return -ENOENT;
-
-	usb_debug_devices = debugfs_create_file("devices", 0444,
-						usb_debug_root, NULL,
-						&usbfs_devices_fops);
-	if (!usb_debug_devices) {
-		debugfs_remove(usb_debug_root);
-		usb_debug_root = NULL;
-		return -ENOENT;
-	}
-
-	return 0;
+	debugfs_create_file("devices", 0444, usb_debug_root, NULL,
+			    &usbfs_devices_fops);
 }
 
 static void usb_debugfs_cleanup(void)
 {
-	debugfs_remove(usb_debug_devices);
-	debugfs_remove(usb_debug_root);
+	debugfs_remove_recursive(usb_debug_root);
 }
 
 /*
@@ -1205,9 +1191,7 @@ static int __init usb_init(void)
 	}
 	usb_init_pool_max();
 
-	retval = usb_debugfs_init();
-	if (retval)
-		goto out;
+	usb_debugfs_init();
 
 	usb_acpi_register();
 	retval = bus_register(&usb_bus_type);
--- a/drivers/usb/dwc2/debugfs.c
+++ b/drivers/usb/dwc2/debugfs.c
@@ -293,52 +293,30 @@ DEFINE_SHOW_ATTRIBUTE(ep);
 static void dwc2_hsotg_create_debug(struct dwc2_hsotg *hsotg)
 {
 	struct dentry *root;
-	struct dentry *file;
 	unsigned int epidx;
 
 	root = hsotg->debug_root;
 
 	/* create general state file */
-
-	file = debugfs_create_file("state", 0444, root, hsotg, &state_fops);
-	if (IS_ERR(file))
-		dev_err(hsotg->dev, "%s: failed to create state\n", __func__);
-
-	file = debugfs_create_file("testmode", 0644, root, hsotg,
-				   &testmode_fops);
-	if (IS_ERR(file))
-		dev_err(hsotg->dev, "%s: failed to create testmode\n",
-			__func__);
-
-	file = debugfs_create_file("fifo", 0444, root, hsotg, &fifo_fops);
-	if (IS_ERR(file))
-		dev_err(hsotg->dev, "%s: failed to create fifo\n", __func__);
+	debugfs_create_file("state", 0444, root, hsotg, &state_fops);
+	debugfs_create_file("testmode", 0644, root, hsotg, &testmode_fops);
+	debugfs_create_file("fifo", 0444, root, hsotg, &fifo_fops);
 
 	/* Create one file for each out endpoint */
 	for (epidx = 0; epidx < hsotg->num_of_eps; epidx++) {
 		struct dwc2_hsotg_ep *ep;
 
 		ep = hsotg->eps_out[epidx];
-		if (ep) {
-			file = debugfs_create_file(ep->name, 0444,
-						   root, ep, &ep_fops);
-			if (IS_ERR(file))
-				dev_err(hsotg->dev, "failed to create %s debug file\n",
-					ep->name);
-		}
+		if (ep)
+			debugfs_create_file(ep->name, 0444, root, ep, &ep_fops);
 	}
 	/* Create one file for each in endpoint. EP0 is handled with out eps */
 	for (epidx = 1; epidx < hsotg->num_of_eps; epidx++) {
 		struct dwc2_hsotg_ep *ep;
 
 		ep = hsotg->eps_in[epidx];
-		if (ep) {
-			file = debugfs_create_file(ep->name, 0444,
-						   root, ep, &ep_fops);
-			if (IS_ERR(file))
-				dev_err(hsotg->dev, "failed to create %s debug file\n",
-					ep->name);
-		}
+		if (ep)
+			debugfs_create_file(ep->name, 0444, root, ep, &ep_fops);
 	}
 }
 #else
@@ -790,32 +768,14 @@ DEFINE_SHOW_ATTRIBUTE(dr_mode);
 int dwc2_debugfs_init(struct dwc2_hsotg *hsotg)
 {
 	int			ret;
-	struct dentry		*file;
+	struct dentry		*root;
 
-	hsotg->debug_root = debugfs_create_dir(dev_name(hsotg->dev), NULL);
-	if (!hsotg->debug_root) {
-		ret = -ENOMEM;
-		goto err0;
-	}
+	root = debugfs_create_dir(dev_name(hsotg->dev), NULL);
+	hsotg->debug_root = root;
 
-	file = debugfs_create_file("params", 0444,
-				   hsotg->debug_root,
-				   hsotg, &params_fops);
-	if (IS_ERR(file))
-		dev_err(hsotg->dev, "%s: failed to create params\n", __func__);
-
-	file = debugfs_create_file("hw_params", 0444,
-				   hsotg->debug_root,
-				   hsotg, &hw_params_fops);
-	if (IS_ERR(file))
-		dev_err(hsotg->dev, "%s: failed to create hw_params\n",
-			__func__);
-
-	file = debugfs_create_file("dr_mode", 0444,
-				   hsotg->debug_root,
-				   hsotg, &dr_mode_fops);
-	if (IS_ERR(file))
-		dev_err(hsotg->dev, "%s: failed to create dr_mode\n", __func__);
+	debugfs_create_file("params", 0444, root, hsotg, &params_fops);
+	debugfs_create_file("hw_params", 0444, root, hsotg, &hw_params_fops);
+	debugfs_create_file("dr_mode", 0444, root, hsotg, &dr_mode_fops);
 
 	/* Add gadget debugfs nodes */
 	dwc2_hsotg_create_debug(hsotg);
@@ -824,24 +784,18 @@ int dwc2_debugfs_init(struct dwc2_hsotg
 								GFP_KERNEL);
 	if (!hsotg->regset) {
 		ret = -ENOMEM;
-		goto err1;
+		goto err;
 	}
 
 	hsotg->regset->regs = dwc2_regs;
 	hsotg->regset->nregs = ARRAY_SIZE(dwc2_regs);
 	hsotg->regset->base = hsotg->regs;
 
-	file = debugfs_create_regset32("regdump", 0444, hsotg->debug_root,
-				       hsotg->regset);
-	if (!file) {
-		ret = -ENOMEM;
-		goto err1;
-	}
+	debugfs_create_regset32("regdump", 0444, root, hsotg->regset);
 
 	return 0;
-err1:
+err:
 	debugfs_remove_recursive(hsotg->debug_root);
-err0:
 	return ret;
 }
 
--- a/drivers/usb/dwc3/debugfs.c
+++ b/drivers/usb/dwc3/debugfs.c
@@ -716,9 +716,6 @@ static void dwc3_debugfs_create_endpoint
 	struct dentry		*dir;
 
 	dir = debugfs_create_dir(dep->name, parent);
-	if (IS_ERR_OR_NULL(dir))
-		return;
-
 	dwc3_debugfs_create_endpoint_files(dep, dir);
 }
 
@@ -740,14 +737,8 @@ static void dwc3_debugfs_create_endpoint
 void dwc3_debugfs_init(struct dwc3 *dwc)
 {
 	struct dentry		*root;
-	struct dentry           *file;
 
 	root = debugfs_create_dir(dev_name(dwc->dev), NULL);
-	if (IS_ERR_OR_NULL(root)) {
-		if (!root)
-			dev_err(dwc->dev, "Can't create debugfs root\n");
-		return;
-	}
 	dwc->root = root;
 
 	dwc->regset = kzalloc(sizeof(*dwc->regset), GFP_KERNEL);
@@ -760,29 +751,19 @@ void dwc3_debugfs_init(struct dwc3 *dwc)
 	dwc->regset->nregs = ARRAY_SIZE(dwc3_regs);
 	dwc->regset->base = dwc->regs - DWC3_GLOBALS_REGS_START;
 
-	file = debugfs_create_regset32("regdump", S_IRUGO, root, dwc->regset);
-	if (!file)
-		dev_dbg(dwc->dev, "Can't create debugfs regdump\n");
+	debugfs_create_regset32("regdump", S_IRUGO, root, dwc->regset);
 
 	if (IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE)) {
-		file = debugfs_create_file("mode", S_IRUGO | S_IWUSR, root,
-				dwc, &dwc3_mode_fops);
-		if (!file)
-			dev_dbg(dwc->dev, "Can't create debugfs mode\n");
+		debugfs_create_file("mode", S_IRUGO | S_IWUSR, root, dwc,
+				    &dwc3_mode_fops);
 	}
 
 	if (IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE) ||
 			IS_ENABLED(CONFIG_USB_DWC3_GADGET)) {
-		file = debugfs_create_file("testmode", S_IRUGO | S_IWUSR, root,
-				dwc, &dwc3_testmode_fops);
-		if (!file)
-			dev_dbg(dwc->dev, "Can't create debugfs testmode\n");
-
-		file = debugfs_create_file("link_state", S_IRUGO | S_IWUSR,
-				root, dwc, &dwc3_link_state_fops);
-		if (!file)
-			dev_dbg(dwc->dev, "Can't create debugfs link_state\n");
-
+		debugfs_create_file("testmode", S_IRUGO | S_IWUSR, root, dwc,
+				    &dwc3_testmode_fops);
+		debugfs_create_file("link_state", S_IRUGO | S_IWUSR, root, dwc,
+				    &dwc3_link_state_fops);
 		dwc3_debugfs_create_endpoint_dirs(dwc, root);
 	}
 }
--- a/drivers/usb/host/ehci-dbg.c
+++ b/drivers/usb/host/ehci-dbg.c
@@ -1028,29 +1028,15 @@ static inline void create_debug_files(st
 	struct usb_bus *bus = &ehci_to_hcd(ehci)->self;
 
 	ehci->debug_dir = debugfs_create_dir(bus->bus_name, ehci_debug_root);
-	if (!ehci->debug_dir)
-		return;
 
-	if (!debugfs_create_file("async", S_IRUGO, ehci->debug_dir, bus,
-						&debug_async_fops))
-		goto file_error;
-
-	if (!debugfs_create_file("bandwidth", S_IRUGO, ehci->debug_dir, bus,
-						&debug_bandwidth_fops))
-		goto file_error;
-
-	if (!debugfs_create_file("periodic", S_IRUGO, ehci->debug_dir, bus,
-						&debug_periodic_fops))
-		goto file_error;
-
-	if (!debugfs_create_file("registers", S_IRUGO, ehci->debug_dir, bus,
-						    &debug_registers_fops))
-		goto file_error;
-
-	return;
-
-file_error:
-	debugfs_remove_recursive(ehci->debug_dir);
+	debugfs_create_file("async", S_IRUGO, ehci->debug_dir, bus,
+			    &debug_async_fops);
+	debugfs_create_file("bandwidth", S_IRUGO, ehci->debug_dir, bus,
+			    &debug_bandwidth_fops);
+	debugfs_create_file("periodic", S_IRUGO, ehci->debug_dir, bus,
+			    &debug_periodic_fops);
+	debugfs_create_file("registers", S_IRUGO, ehci->debug_dir, bus,
+			    &debug_registers_fops);
 }
 
 static inline void remove_debug_files(struct ehci_hcd *ehci)
--- a/drivers/usb/mon/mon_text.c
+++ b/drivers/usb/mon/mon_text.c
@@ -700,7 +700,6 @@ static const struct file_operations mon_
 
 int mon_text_add(struct mon_bus *mbus, const struct usb_bus *ubus)
 {
-	struct dentry *d;
 	enum { NAMESZ = 10 };
 	char name[NAMESZ];
 	int busnum = ubus? ubus->busnum: 0;
@@ -713,42 +712,32 @@ int mon_text_add(struct mon_bus *mbus, c
 		rc = snprintf(name, NAMESZ, "%dt", busnum);
 		if (rc <= 0 || rc >= NAMESZ)
 			goto err_print_t;
-		d = debugfs_create_file(name, 0600, mon_dir, mbus,
+		mbus->dent_t = debugfs_create_file(name, 0600, mon_dir, mbus,
 							     &mon_fops_text_t);
-		if (d == NULL)
-			goto err_create_t;
-		mbus->dent_t = d;
 	}
 
 	rc = snprintf(name, NAMESZ, "%du", busnum);
 	if (rc <= 0 || rc >= NAMESZ)
 		goto err_print_u;
-	d = debugfs_create_file(name, 0600, mon_dir, mbus, &mon_fops_text_u);
-	if (d == NULL)
-		goto err_create_u;
-	mbus->dent_u = d;
+	mbus->dent_u = debugfs_create_file(name, 0600, mon_dir, mbus,
+					   &mon_fops_text_u);
 
 	rc = snprintf(name, NAMESZ, "%ds", busnum);
 	if (rc <= 0 || rc >= NAMESZ)
 		goto err_print_s;
-	d = debugfs_create_file(name, 0600, mon_dir, mbus, &mon_fops_stat);
-	if (d == NULL)
-		goto err_create_s;
-	mbus->dent_s = d;
+	mbus->dent_s = debugfs_create_file(name, 0600, mon_dir, mbus,
+					   &mon_fops_stat);
 
 	return 1;
 
-err_create_s:
 err_print_s:
 	debugfs_remove(mbus->dent_u);
 	mbus->dent_u = NULL;
-err_create_u:
 err_print_u:
 	if (ubus != NULL) {
 		debugfs_remove(mbus->dent_t);
 		mbus->dent_t = NULL;
 	}
-err_create_t:
 err_print_t:
 	return 0;
 }
@@ -756,8 +745,7 @@ err_print_t:
 void mon_text_del(struct mon_bus *mbus)
 {
 	debugfs_remove(mbus->dent_u);
-	if (mbus->dent_t != NULL)
-		debugfs_remove(mbus->dent_t);
+	debugfs_remove(mbus->dent_t);
 	debugfs_remove(mbus->dent_s);
 }
 
@@ -775,18 +763,7 @@ static void mon_text_ctor(void *mem)
 
 int __init mon_text_init(void)
 {
-	struct dentry *mondir;
-
-	mondir = debugfs_create_dir("usbmon", usb_debug_root);
-	if (IS_ERR(mondir)) {
-		/* debugfs not available, but we can use usbmon without it */
-		return 0;
-	}
-	if (mondir == NULL) {
-		printk(KERN_NOTICE TAG ": unable to create usbmon directory\n");
-		return -ENOMEM;
-	}
-	mon_dir = mondir;
+	mon_dir = debugfs_create_dir("usbmon", usb_debug_root);
 	return 0;
 }