diff mbox series

[v2] USB: move usb debugfs directory creation to the usb common core

Message ID 20190605092816.GA23758@kroah.com (mailing list archive)
State New, archived
Headers show
Series [v2] USB: move usb debugfs directory creation to the usb common core | expand

Commit Message

Greg Kroah-Hartman June 5, 2019, 9:28 a.m. UTC
The USB gadget subsystem wants to use the USB debugfs root directory, so
move it to the common "core" USB code so that it is properly initialized
and removed as needed.

In order to properly do this, we need to load the common code before the
usb core code, when everything is linked into the kernel, so reorder the
link order of the code.

Also as the usb common code has the possibility of the led trigger logic
to be merged into it, handle the build option properly by only having
one module init/exit function and have the common code initialize the
led trigger if needed.

Reported-by: From: Chunfeng Yun <chunfeng.yun@mediatek.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

Chunfeng, can you test this version to verify it works for you when
building the code into the kernel?

v2: handle led common code link error reported by kbuild
    handle subsys_initcall issue pointed out by Chunfeng

 drivers/usb/Makefile        |  3 +--
 drivers/usb/common/common.c | 21 +++++++++++++++++++++
 drivers/usb/common/common.h | 14 ++++++++++++++
 drivers/usb/common/led.c    |  9 +++------
 drivers/usb/core/usb.c      | 10 ++++------
 5 files changed, 43 insertions(+), 14 deletions(-)
 create mode 100644 drivers/usb/common/common.h

Comments

Chunfeng Yun (云春峰) June 5, 2019, 11:01 a.m. UTC | #1
Hi Greg,
On Wed, 2019-06-05 at 11:28 +0200, Greg Kroah-Hartman wrote:
> The USB gadget subsystem wants to use the USB debugfs root directory, so
> move it to the common "core" USB code so that it is properly initialized
> and removed as needed.
> 
> In order to properly do this, we need to load the common code before the
> usb core code, when everything is linked into the kernel, so reorder the
> link order of the code.
> 
> Also as the usb common code has the possibility of the led trigger logic
> to be merged into it, handle the build option properly by only having
> one module init/exit function and have the common code initialize the
> led trigger if needed.
> 
> Reported-by: From: Chunfeng Yun <chunfeng.yun@mediatek.com>
> Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
> 
> Chunfeng, can you test this version to verify it works for you when
> building the code into the kernel?
> 
> v2: handle led common code link error reported by kbuild
>     handle subsys_initcall issue pointed out by Chunfeng
> 
>  drivers/usb/Makefile        |  3 +--
>  drivers/usb/common/common.c | 21 +++++++++++++++++++++
>  drivers/usb/common/common.h | 14 ++++++++++++++
>  drivers/usb/common/led.c    |  9 +++------
>  drivers/usb/core/usb.c      | 10 ++++------
>  5 files changed, 43 insertions(+), 14 deletions(-)
>  create mode 100644 drivers/usb/common/common.h
> 
> diff --git a/drivers/usb/Makefile b/drivers/usb/Makefile
> index 7d1b8c82b208..ecc2de1ffaae 100644
> --- a/drivers/usb/Makefile
> +++ b/drivers/usb/Makefile
> @@ -5,6 +5,7 @@
>  
>  # Object files in subdirectories
>  
> +obj-$(CONFIG_USB_COMMON)	+= common/
>  obj-$(CONFIG_USB)		+= core/
>  obj-$(CONFIG_USB_SUPPORT)	+= phy/
>  
> @@ -60,8 +61,6 @@ obj-$(CONFIG_USB_CHIPIDEA)	+= chipidea/
>  obj-$(CONFIG_USB_RENESAS_USBHS)	+= renesas_usbhs/
>  obj-$(CONFIG_USB_GADGET)	+= gadget/
>  
> -obj-$(CONFIG_USB_COMMON)	+= common/
> -
>  obj-$(CONFIG_USBIP_CORE)	+= usbip/
>  
>  obj-$(CONFIG_TYPEC)		+= typec/
> diff --git a/drivers/usb/common/common.c b/drivers/usb/common/common.c
> index 18f5dcf58b0d..84a4423aaddf 100644
> --- a/drivers/usb/common/common.c
> +++ b/drivers/usb/common/common.c
> @@ -15,6 +15,8 @@
>  #include <linux/usb/of.h>
>  #include <linux/usb/otg.h>
>  #include <linux/of_platform.h>
> +#include <linux/debugfs.h>
> +#include "common.h"
>  
>  static const char *const ep_type_names[] = {
>  	[USB_ENDPOINT_XFER_CONTROL] = "ctrl",
> @@ -291,4 +293,23 @@ struct device *usb_of_get_companion_dev(struct device *dev)
>  EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);
>  #endif
>  
> +struct dentry *usb_debug_root;
> +EXPORT_SYMBOL_GPL(usb_debug_root);
> +
> +static int usb_common_init(void)
> +{
> +	usb_debug_root = debugfs_create_dir("usb", NULL);
> +	ledtrig_usb_init();
> +	return 0;
> +}
> +
> +static void usb_common_exit(void)
> +{
> +	ledtrig_usb_exit();
> +	debugfs_remove_recursive(usb_debug_root);
> +}
> +
When enable CONFIG_LED_TRIGGER, there is a warning

 MODPOST vmlinux.o
WARNING: vmlinux.o(.text+0x68e300): Section mismatch in reference from
the function usb_common_init() to the
function .init.text:ledtrig_usb_init()
The function usb_common_init() references
the function __init ledtrig_usb_init().
This is often because usb_common_init lacks a __init
annotation or the annotation of ledtrig_usb_init is wrong.

WARNING: vmlinux.o(.text+0x68e318): Section mismatch in reference from
the function usb_common_exit() to the
function .exit.text:ledtrig_usb_exit()
The function usb_common_exit() references a function in an exit section.
Often the function ledtrig_usb_exit() has valid usage outside the exit
section
and the fix is to remove the __exit annotation of ledtrig_usb_exit.

seems need add __init and __exit for usb_common_init/exit

> +subsys_initcall(usb_common_init);
> +module_exit(usb_common_exit);
> +
>  MODULE_LICENSE("GPL");
> diff --git a/drivers/usb/common/common.h b/drivers/usb/common/common.h
> new file mode 100644
> index 000000000000..424a91316a4b
> --- /dev/null
> +++ b/drivers/usb/common/common.h
> @@ -0,0 +1,14 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +
> +#ifndef __LINUX_USB_COMMON_H
> +#define __LINUX_USB_COMMON_H
> +
> +#if defined(CONFIG_USB_LED_TRIG)
> +void ledtrig_usb_init(void);
> +void ledtrig_usb_exit(void);
> +#else
> +static inline void ledtrig_usb_init(void) { }
> +static inline void ledtrig_usb_exit(void) { }
> +#endif
> +
> +#endif	/* __LINUX_USB_COMMON_H */
> diff --git a/drivers/usb/common/led.c b/drivers/usb/common/led.c
> index 7bd81166b77d..0865dd44a80a 100644
> --- a/drivers/usb/common/led.c
> +++ b/drivers/usb/common/led.c
> @@ -10,6 +10,7 @@
>  #include <linux/init.h>
>  #include <linux/leds.h>
>  #include <linux/usb.h>
> +#include "common.h"
>  
>  #define BLINK_DELAY 30
>  
> @@ -36,18 +37,14 @@ void usb_led_activity(enum usb_led_event ev)
>  EXPORT_SYMBOL_GPL(usb_led_activity);
>  
> 
> -static int __init ledtrig_usb_init(void)
> +void __init ledtrig_usb_init(void)
>  {
>  	led_trigger_register_simple("usb-gadget", &ledtrig_usb_gadget);
>  	led_trigger_register_simple("usb-host", &ledtrig_usb_host);
> -	return 0;
>  }
>  
> -static void __exit ledtrig_usb_exit(void)
> +void __exit ledtrig_usb_exit(void)
>  {
>  	led_trigger_unregister_simple(ledtrig_usb_gadget);
>  	led_trigger_unregister_simple(ledtrig_usb_host);
>  }
> -
> -module_init(ledtrig_usb_init);
> -module_exit(ledtrig_usb_exit);
> diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
> index 7fcb9f782931..5a0df527a8ca 100644
> --- a/drivers/usb/core/usb.c
> +++ b/drivers/usb/core/usb.c
> @@ -1185,19 +1185,17 @@ static struct notifier_block usb_bus_nb = {
>  	.notifier_call = usb_bus_notify,
>  };
>  
> -struct dentry *usb_debug_root;
> -EXPORT_SYMBOL_GPL(usb_debug_root);
> +static struct dentry *usb_devices_root;
>  
>  static void usb_debugfs_init(void)
>  {
> -	usb_debug_root = debugfs_create_dir("usb", NULL);
> -	debugfs_create_file("devices", 0444, usb_debug_root, NULL,
> -			    &usbfs_devices_fops);
> +	usb_devices_root = debugfs_create_file("devices", 0444, usb_debug_root,
> +					       NULL, &usbfs_devices_fops);
>  }
>  
>  static void usb_debugfs_cleanup(void)
>  {
> -	debugfs_remove_recursive(usb_debug_root);
> +	debugfs_remove(usb_devices_root);
>  }
>  
>  /*
Greg Kroah-Hartman June 5, 2019, 12:40 p.m. UTC | #2
On Wed, Jun 05, 2019 at 07:01:55PM +0800, Chunfeng Yun wrote:
> Hi Greg,
> On Wed, 2019-06-05 at 11:28 +0200, Greg Kroah-Hartman wrote:
> > The USB gadget subsystem wants to use the USB debugfs root directory, so
> > move it to the common "core" USB code so that it is properly initialized
> > and removed as needed.
> > 
> > In order to properly do this, we need to load the common code before the
> > usb core code, when everything is linked into the kernel, so reorder the
> > link order of the code.
> > 
> > Also as the usb common code has the possibility of the led trigger logic
> > to be merged into it, handle the build option properly by only having
> > one module init/exit function and have the common code initialize the
> > led trigger if needed.
> > 
> > Reported-by: From: Chunfeng Yun <chunfeng.yun@mediatek.com>
> > Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > ---
> > 
> > Chunfeng, can you test this version to verify it works for you when
> > building the code into the kernel?
> > 
> > v2: handle led common code link error reported by kbuild
> >     handle subsys_initcall issue pointed out by Chunfeng
> > 
> >  drivers/usb/Makefile        |  3 +--
> >  drivers/usb/common/common.c | 21 +++++++++++++++++++++
> >  drivers/usb/common/common.h | 14 ++++++++++++++
> >  drivers/usb/common/led.c    |  9 +++------
> >  drivers/usb/core/usb.c      | 10 ++++------
> >  5 files changed, 43 insertions(+), 14 deletions(-)
> >  create mode 100644 drivers/usb/common/common.h
> > 
> > diff --git a/drivers/usb/Makefile b/drivers/usb/Makefile
> > index 7d1b8c82b208..ecc2de1ffaae 100644
> > --- a/drivers/usb/Makefile
> > +++ b/drivers/usb/Makefile
> > @@ -5,6 +5,7 @@
> >  
> >  # Object files in subdirectories
> >  
> > +obj-$(CONFIG_USB_COMMON)	+= common/
> >  obj-$(CONFIG_USB)		+= core/
> >  obj-$(CONFIG_USB_SUPPORT)	+= phy/
> >  
> > @@ -60,8 +61,6 @@ obj-$(CONFIG_USB_CHIPIDEA)	+= chipidea/
> >  obj-$(CONFIG_USB_RENESAS_USBHS)	+= renesas_usbhs/
> >  obj-$(CONFIG_USB_GADGET)	+= gadget/
> >  
> > -obj-$(CONFIG_USB_COMMON)	+= common/
> > -
> >  obj-$(CONFIG_USBIP_CORE)	+= usbip/
> >  
> >  obj-$(CONFIG_TYPEC)		+= typec/
> > diff --git a/drivers/usb/common/common.c b/drivers/usb/common/common.c
> > index 18f5dcf58b0d..84a4423aaddf 100644
> > --- a/drivers/usb/common/common.c
> > +++ b/drivers/usb/common/common.c
> > @@ -15,6 +15,8 @@
> >  #include <linux/usb/of.h>
> >  #include <linux/usb/otg.h>
> >  #include <linux/of_platform.h>
> > +#include <linux/debugfs.h>
> > +#include "common.h"
> >  
> >  static const char *const ep_type_names[] = {
> >  	[USB_ENDPOINT_XFER_CONTROL] = "ctrl",
> > @@ -291,4 +293,23 @@ struct device *usb_of_get_companion_dev(struct device *dev)
> >  EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);
> >  #endif
> >  
> > +struct dentry *usb_debug_root;
> > +EXPORT_SYMBOL_GPL(usb_debug_root);
> > +
> > +static int usb_common_init(void)
> > +{
> > +	usb_debug_root = debugfs_create_dir("usb", NULL);
> > +	ledtrig_usb_init();
> > +	return 0;
> > +}
> > +
> > +static void usb_common_exit(void)
> > +{
> > +	ledtrig_usb_exit();
> > +	debugfs_remove_recursive(usb_debug_root);
> > +}
> > +
> When enable CONFIG_LED_TRIGGER, there is a warning
> 
>  MODPOST vmlinux.o
> WARNING: vmlinux.o(.text+0x68e300): Section mismatch in reference from
> the function usb_common_init() to the
> function .init.text:ledtrig_usb_init()
> The function usb_common_init() references
> the function __init ledtrig_usb_init().
> This is often because usb_common_init lacks a __init
> annotation or the annotation of ledtrig_usb_init is wrong.
> 
> WARNING: vmlinux.o(.text+0x68e318): Section mismatch in reference from
> the function usb_common_exit() to the
> function .exit.text:ledtrig_usb_exit()
> The function usb_common_exit() references a function in an exit section.
> Often the function ledtrig_usb_exit() has valid usage outside the exit
> section
> and the fix is to remove the __exit annotation of ledtrig_usb_exit.
> 
> seems need add __init and __exit for usb_common_init/exit

Yes, you are right, I'll go add those markings to those functions, good
catch.

greg k-h
diff mbox series

Patch

diff --git a/drivers/usb/Makefile b/drivers/usb/Makefile
index 7d1b8c82b208..ecc2de1ffaae 100644
--- a/drivers/usb/Makefile
+++ b/drivers/usb/Makefile
@@ -5,6 +5,7 @@ 
 
 # Object files in subdirectories
 
+obj-$(CONFIG_USB_COMMON)	+= common/
 obj-$(CONFIG_USB)		+= core/
 obj-$(CONFIG_USB_SUPPORT)	+= phy/
 
@@ -60,8 +61,6 @@  obj-$(CONFIG_USB_CHIPIDEA)	+= chipidea/
 obj-$(CONFIG_USB_RENESAS_USBHS)	+= renesas_usbhs/
 obj-$(CONFIG_USB_GADGET)	+= gadget/
 
-obj-$(CONFIG_USB_COMMON)	+= common/
-
 obj-$(CONFIG_USBIP_CORE)	+= usbip/
 
 obj-$(CONFIG_TYPEC)		+= typec/
diff --git a/drivers/usb/common/common.c b/drivers/usb/common/common.c
index 18f5dcf58b0d..84a4423aaddf 100644
--- a/drivers/usb/common/common.c
+++ b/drivers/usb/common/common.c
@@ -15,6 +15,8 @@ 
 #include <linux/usb/of.h>
 #include <linux/usb/otg.h>
 #include <linux/of_platform.h>
+#include <linux/debugfs.h>
+#include "common.h"
 
 static const char *const ep_type_names[] = {
 	[USB_ENDPOINT_XFER_CONTROL] = "ctrl",
@@ -291,4 +293,23 @@  struct device *usb_of_get_companion_dev(struct device *dev)
 EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);
 #endif
 
+struct dentry *usb_debug_root;
+EXPORT_SYMBOL_GPL(usb_debug_root);
+
+static int usb_common_init(void)
+{
+	usb_debug_root = debugfs_create_dir("usb", NULL);
+	ledtrig_usb_init();
+	return 0;
+}
+
+static void usb_common_exit(void)
+{
+	ledtrig_usb_exit();
+	debugfs_remove_recursive(usb_debug_root);
+}
+
+subsys_initcall(usb_common_init);
+module_exit(usb_common_exit);
+
 MODULE_LICENSE("GPL");
diff --git a/drivers/usb/common/common.h b/drivers/usb/common/common.h
new file mode 100644
index 000000000000..424a91316a4b
--- /dev/null
+++ b/drivers/usb/common/common.h
@@ -0,0 +1,14 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __LINUX_USB_COMMON_H
+#define __LINUX_USB_COMMON_H
+
+#if defined(CONFIG_USB_LED_TRIG)
+void ledtrig_usb_init(void);
+void ledtrig_usb_exit(void);
+#else
+static inline void ledtrig_usb_init(void) { }
+static inline void ledtrig_usb_exit(void) { }
+#endif
+
+#endif	/* __LINUX_USB_COMMON_H */
diff --git a/drivers/usb/common/led.c b/drivers/usb/common/led.c
index 7bd81166b77d..0865dd44a80a 100644
--- a/drivers/usb/common/led.c
+++ b/drivers/usb/common/led.c
@@ -10,6 +10,7 @@ 
 #include <linux/init.h>
 #include <linux/leds.h>
 #include <linux/usb.h>
+#include "common.h"
 
 #define BLINK_DELAY 30
 
@@ -36,18 +37,14 @@  void usb_led_activity(enum usb_led_event ev)
 EXPORT_SYMBOL_GPL(usb_led_activity);
 
 
-static int __init ledtrig_usb_init(void)
+void __init ledtrig_usb_init(void)
 {
 	led_trigger_register_simple("usb-gadget", &ledtrig_usb_gadget);
 	led_trigger_register_simple("usb-host", &ledtrig_usb_host);
-	return 0;
 }
 
-static void __exit ledtrig_usb_exit(void)
+void __exit ledtrig_usb_exit(void)
 {
 	led_trigger_unregister_simple(ledtrig_usb_gadget);
 	led_trigger_unregister_simple(ledtrig_usb_host);
 }
-
-module_init(ledtrig_usb_init);
-module_exit(ledtrig_usb_exit);
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index 7fcb9f782931..5a0df527a8ca 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -1185,19 +1185,17 @@  static struct notifier_block usb_bus_nb = {
 	.notifier_call = usb_bus_notify,
 };
 
-struct dentry *usb_debug_root;
-EXPORT_SYMBOL_GPL(usb_debug_root);
+static struct dentry *usb_devices_root;
 
 static void usb_debugfs_init(void)
 {
-	usb_debug_root = debugfs_create_dir("usb", NULL);
-	debugfs_create_file("devices", 0444, usb_debug_root, NULL,
-			    &usbfs_devices_fops);
+	usb_devices_root = debugfs_create_file("devices", 0444, usb_debug_root,
+					       NULL, &usbfs_devices_fops);
 }
 
 static void usb_debugfs_cleanup(void)
 {
-	debugfs_remove_recursive(usb_debug_root);
+	debugfs_remove(usb_devices_root);
 }
 
 /*