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hid: only dump report traffic with debug level 2

PATCH In review Anssi Hannula 2 participants 6 messages Mar 21, 2008 – Mar 22, 2008 HID

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Anssi Hannula

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#0 lore raw

PATCH 1/1 hid: only dump report traffic with debug level 2

Currently using debug=1 with hid module prints out all sent and received reports to the kernel log, while in many cases we only want to see the report descriptors and hid-input mappings that are printed when a device is probed.

Add new level debug=2, and only dump the report traffic with that level.

Signed-off-by Anssi Hannula <[email protected]>

---

drivers/hid/hid-core.c +2 -2
Index: linux-2.6.24-verbosehid/drivers/hid/hid-core.c
===================================================================
@@ -43,8 +43,8 @@
 
 #ifdef CONFIG_HID_DEBUG
 int hid_debug = 0;
-module_param_named(debug, hid_debug, bool, 0600);
-MODULE_PARM_DESC(debug, "Turn HID debugging mode on and off");
+module_param_named(debug, hid_debug, int, 0600);
+MODULE_PARM_DESC(debug, "HID debugging (0=off, 1=probing info, 2=continuous data dumping)");
 EXPORT_SYMBOL_GPL(hid_debug);
 #endif
drivers/hid/hid-debug.c +1 -1
Index: linux-2.6.24-verbosehid/drivers/hid/hid-debug.c
===================================================================
@@ -498,7 +498,7 @@
 EXPORT_SYMBOL_GPL(hid_dump_device);
 
 void hid_dump_input(struct hid_usage *usage, __s32 value) {
-	if (!hid_debug)
+	if (hid_debug < 2)
 		return;
 
 	printk(KERN_DEBUG "hid-debug: input ");

-- Anssi Hannula

#1 lore raw
Quoted 4 lines · Anssi Hannula

Currently using debug=1 with hid module prints out all sent and received reports to the kernel log, while in many cases we only want to see the report descriptors and hid-input mappings that are printed when a device is probed.

Hi Anssi,

thanks for your patch, I agree that making this more configurable makes sense.

But I would propose staying backwards compatible, i.e. debug=1 does the whole dump, debug=2 excludes the individual reports but still dumps the report descriptor and mappings etc. What do you think?

Thanks,

Signature · 2 lines
Jiri Kosina
SUSE Labs
author
#2 lore raw
Quoted 7 lines · Jiri Kosina
Quoted 4 lines · Anssi Hannula

Currently using debug=1 with hid module prints out all sent and received reports to the kernel log, while in many cases we only want to see the report descriptors and hid-input mappings that are printed when a device is probed.

Quoted 8 lines

Hi Anssi,

thanks for your patch, I agree that making this more configurable makes sense.

But I would propose staying backwards compatible, i.e. debug=1 does the whole dump, debug=2 excludes the individual reports but still dumps the report descriptor and mappings etc. What do you think?

Well, I think having higher debug level should mean more debugging output and that this logic is more important than backwards compatibility of a debug option, it is not like it is going to break any software or so.

But I don't care too much about it, feel free to do it the other way as well :)

Signature · 1 line
Anssi Hannula
#3 lore raw
Quoted 4 lines · Anssi Hannula

Well, I think having higher debug level should mean more debugging output and that this logic is more important than backwards compatibility of a debug option, it is not like it is going to break any software or so.

I agee. On the other hand, I am currently quite often telling people who (for example) complain about non-functioning keys on some expotic keyboard "just modprobe the hid module with debug=1, press the non-functioning key, and send me dmesg output". This would now be different depending on the kernel version they use, which I don't like too much.

Thanks,

Signature · 2 lines
Jiri Kosina
SUSE Labs
author
#4 lore raw
Quoted 7 lines · Jiri Kosina
Quoted 4 lines · Anssi Hannula

Well, I think having higher debug level should mean more debugging output and that this logic is more important than backwards compatibility of a debug option, it is not like it is going to break any software or so.

Quoted 5 lines

I agee. On the other hand, I am currently quite often telling people who (for example) complain about non-functioning keys on some expotic keyboard "just modprobe the hid module with debug=1, press the non-functioning key, and send me dmesg output". This would now be different depending on the kernel version they use, which I don't like too much.

Wouldn't debug=2 work with older kernel versions as well?

Signature · 1 line
Anssi Hannula
#5 lore raw
Quoted 7 lines · Anssi Hannula
Quoted 6 lines

I agee. On the other hand, I am currently quite often telling people who (for example) complain about non-functioning keys on some expotic keyboard "just modprobe the hid module with debug=1, press the non-functioning key, and send me dmesg output". This would now be different depending on the kernel version they use, which I don't like too much.

Wouldn't debug=2 work with older kernel versions as well?

Of course it would, I need to have some rest, sorry for the noise :)

I will apply your patch to my tree, thanks.

Signature · 2 lines
Jiri Kosina
SUSE Labs