Thread: [Libusb-devel] libusb on Android, crash in usbi_log()

A cross-platform library that gives apps easy access to USB devices

Brought to you by: cdickens, dsd_, hjelmn, jerdfelt, and 5 others

libusb-devel

[Libusb-devel] libusb on Android, crash in usbi_log()

From: Colin M. <clm...@ma...> - 2011-04-11 21:54:13

Details written here:

http://stackoverflow.com/questions/5599238/libusb-crash-on-android-arm-device-emulator

Basically, just trying to be able to access a device plugged into an Android device to send/receive data, but am stuck at libusb (1.0.8 and 1.0.3) crashing when trying to log (it appears).

Happy to provide any and all other info that would help.  Thanks.

Colin

Re: [Libusb-devel] libusb on Android, crash in usbi_log()

From: Xiaofan C. <xia...@gm...> - 2011-04-11 23:39:08

On Tue, Apr 12, 2011 at 5:53 AM, Colin Madere <clm...@ma...> wrote:
> Details written here:
>
> http://stackoverflow.com/questions/5599238/libusb-crash-on-android-arm-device-emulator
>
> Basically, just trying to be able to access a device plugged into an
> Android device to send/receive data, but am stuck at libusb (1.0.8 and 1.0.3)
> crashing when trying to log (it appears).

Hmm, does Android ship with libusb-1.0 or not? And is this an
official Android OS or this is a 3rd party hack?

> Happy to provide any and all other info that would help.  Thanks.

How do you build libusb-1.0? What if you disable debug logging?
Could you please post the crash log? Could you try
latest libusb-stuge.git?

-- 
Xiaofan

Re: [Libusb-devel] libusb on Android, crash in usbi_log()

From: Xiaofan C. <xia...@gm...> - 2011-04-12 01:53:34

Attachments: crash_log.zip

Please keep the list in CC. Thanks.

On Tue, Apr 12, 2011 at 8:22 AM, Colin Madere <clm...@ma...> wrote:
> On Apr 11, 2011, at 7:38 PM, Xiaofan Chen wrote:
>
>> On Tue, Apr 12, 2011 at 5:53 AM, Colin Madere <clm...@ma...> wrote:
>>> Details written here:
>>>
>>> http://stackoverflow.com/questions/5599238/libusb-crash-on-android-arm-device-emulator
>>>
>>> Basically, just trying to be able to access a device plugged into an
>>> Android device to send/receive data, but am stuck at libusb (1.0.8 and 1.0.3)
>>> crashing when trying to log (it appears).
>>
>> Hmm, does Android ship with libusb-1.0 or not? And is this an
>> official Android OS or this is a 3rd party hack?
>>
>>> Happy to provide any and all other info that would help.  Thanks.
>>
>> How do you build libusb-1.0? What if you disable debug logging?
>> Could you please post the crash log? Could you try
>> latest libusb-stuge.git?
> Standard Android 2.2, no hacks.  I could not find anything regarding
> Android 2.2 shipping with libusb so I figured it was not.  Attempting to
> load libusb without providing a .so gives "Unsatisfied link error", so if it
> is shipped with, it is named something different (would be great if it was!).
>
> I built libusb with the Android.mk provided in the link to the "monaka"
> builds linked in the post provided.  Using the Android NDK to build it.
>
> As noted in the SO post, I used tools provided with the NDK to track
> down where in the library the crash was occuring based on this
> (and other instances of this) log.  The "darkcorner" stuff is me, the
> shared lib is packaged in an APK with a 3-line android application that
> just calls into libusb to do what the "lsusb" sample program does
> (code copied directly, zero changes).
>
> I will try latest as soon as I can.
>
> Crash log:

The full crash log is too big for the list. So it is attached as a zip file.

> 04-11 20:17:03.634: INFO/DEBUG(8870): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
> 04-11 20:17:03.634: INFO/DEBUG(8870): Build fingerprint: 'google/passion_vf/passion/mahimahi:2.2.1/FRG83D/291266:user/release-keys'
> 04-11 20:17:03.634: INFO/DEBUG(8870): pid: 10251, tid: 10251  >>> com.darkcorner.android.sutec <<<
> 04-11 20:17:03.634: INFO/DEBUG(8870): signal 11 (SIGSEGV), fault addr 00000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): r0 00000000  r1 00000003  r2 8080823c  r3 80807114
> 04-11 20:17:03.634: INFO/DEBUG(8870): r4 ffffef5c  r5 80808138  r6 00000000  r7 0022d338
> 04-11 20:17:03.634: INFO/DEBUG(8870): r8 be9274f8  r9 4186bcdc  10 4186bcc4  fp 00000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): ip 8080815c  sp be9263e0  lr 808065f9  pc 80801d8c  cpsr 60000030
> 04-11 20:17:03.634: INFO/DEBUG(8870): d0  643a64696f72646e  d1  6472656767756265
> 04-11 20:17:03.634: INFO/DEBUG(8870): d2  5363657475532f73  d3  7463417375746174
> 04-11 20:17:03.634: INFO/DEBUG(8870): d4  0200000801010098  d5  0000000001010036
> 04-11 20:17:03.634: INFO/DEBUG(8870): d6  1c00000801010099  d7  41600000ffff9200
> 04-11 20:17:03.634: INFO/DEBUG(8870): d8  0000000000000000  d9  0000000000000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): d10 0000000000000000  d11 0000000000000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): d12 0000000000000000  d13 0000000000000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): d14 0000000000000000  d15 0000000000000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): d16 000000070000002b  d17 bff0000000000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): d18 3ff0000000000000  d19 0000000000000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): d20 0000000000000000  d21 0000000000000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): d22 3ff0000000000000  d23 0000000000000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): d24 3ff0000000000000  d25 0000000000000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): d26 0000000000000000  d27 0000000000000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): d28 0000000000000000  d29 0000000000000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): d30 0000000000000000  d31 0000000000000000
> 04-11 20:17:03.634: INFO/DEBUG(8870): scr 20000012
> 04-11 20:17:03.664: INFO/DEBUG(8870): #00  pc 00001d8c  /data/data/com.darkcorner.android.sutec/lib/libusb.so
> 04-11 20:17:03.664: INFO/DEBUG(8870): #01  pc 000065f4  /data/data/com.darkcorner.android.sutec/lib/libusb.so
> 04-11 20:17:03.664: INFO/DEBUG(8870): #02  pc 00002176  /data/data/com.darkcorner.android.sutec/lib/libusb.so
> 04-11 20:17:03.664: INFO/DEBUG(8870): #03  pc 0000686a  /data/data/com.darkcorner.android.sutec/lib/libusb.so
> 04-11 20:17:03.664: INFO/DEBUG(8870): #04  pc 0000688a  /data/data/com.darkcorner.android.sutec/lib/libusb.so
> 04-11 20:17:03.664: INFO/DEBUG(8870): #05  pc 00010e34  /system/lib/libdvm.so
> 04-11 20:17:03.664: INFO/DEBUG(8870): #06  pc 0003f2c4  /system/lib/libdvm.so
> 04-11 20:17:03.664: INFO/DEBUG(8870): #07  pc 000449ea  /system/lib/libdvm.so
> 04-11 20:17:03.664: INFO/DEBUG(8870): #08  pc 00015d98  /system/lib/libdvm.so
> 04-11 20:17:03.664: INFO/DEBUG(8870): #09  pc 0001c794  /system/lib/libdvm.so
> 04-11 20:17:03.674: INFO/DEBUG(8870): #10  pc 0001b634  /system/lib/libdvm.so
> 04-11 20:17:03.674: INFO/DEBUG(8870): #11  pc 0005678e  /system/lib/libdvm.so
> 04-11 20:17:03.684: INFO/DEBUG(8870): #12  pc 0005ee58  /system/lib/libdvm.so
> 04-11 20:17:03.684: INFO/DEBUG(8870): #13  pc 00015d98  /system/lib/libdvm.so
> 04-11 20:17:03.684: INFO/DEBUG(8870): #14  pc 0001c794  /system/lib/libdvm.so
> 04-11 20:17:03.684: INFO/DEBUG(8870): #15  pc 0001b634  /system/lib/libdvm.so
> 04-11 20:17:03.684: INFO/DEBUG(8870): #16  pc 000565cc  /system/lib/libdvm.so
> 04-11 20:17:03.684: INFO/DEBUG(8870): #17  pc 00041c96  /system/lib/libdvm.so
> 04-11 20:17:03.684: INFO/DEBUG(8870): #18  pc 0002d894  /system/lib/libandroid_runtime.so
> 04-11 20:17:03.684: INFO/DEBUG(8870): #19  pc 0002e990  /system/lib/libandroid_runtime.so
> 04-11 20:17:03.684: INFO/DEBUG(8870): #20  pc 00008ca8  /system/bin/app_process
...
...


-- 
Xiaofan

Re: [Libusb-devel] libusb on Android, crash in usbi_log()

From: Colin M. <clm...@ma...> - 2011-04-14 17:43:56

If anyone finds an answer to this, please email me directly since I am now moving to a different potential solution and will be dropping off the list since I won't be using libusb on the current project (but still am interested in a solution).

Thanks.
clm_lists-at-mac.com

On Apr 11, 2011, at 9:16 PM, Xiaofan Chen wrote:

> On Tue, Apr 12, 2011 at 8:22 AM, Colin Madere <clm...@ma...> wrote:
>> On Apr 11, 2011, at 7:38 PM, Xiaofan Chen wrote:
>> 
>>> On Tue, Apr 12, 2011 at 5:53 AM, Colin Madere <clm...@ma...> wrote:
>>>> Details written here:
>>>> 
>>>> http://stackoverflow.com/questions/5599238/libusb-crash-on-android-arm-device-emulator
>>>> 
>>>> Basically, just trying to be able to access a device plugged into an
>>>> Android device to send/receive data, but am stuck at libusb (1.0.8 and 1.0.3)
>>>> crashing when trying to log (it appears).
>>> 
>>> Hmm, does Android ship with libusb-1.0 or not? And is this an
>>> official Android OS or this is a 3rd party hack?
>>> 
>>>> Happy to provide any and all other info that would help.  Thanks.
>>> 
>>> How do you build libusb-1.0? What if you disable debug logging?
>>> Could you please post the crash log? Could you try
>>> latest libusb-stuge.git?
>>> 
>> 
>> Standard Android 2.2, no hacks.  I could not find anything regarding
>> Android 2.2 shipping with libusb so I figured it was not.  Attempting
>> to load libusb without providing a .so gives "Unsatisfied link error",
>> so if it is shipped with, it is named something different (would be
>> great if it was!).
>> 
>> I built libusb with the Android.mk provided in the link to the
>> "monaka" builds linked in the post provided.  Using the Android
>> NDK to build it.
>> 
>> As noted in the SO post, I used tools provided with the NDK to track
>> down where in the library the crash was occuring based on this
>> (and other instances of this) log.  The "darkcorner" stuff is me,
>> the shared lib is packaged in an APK with a 3-line android
>> application that just calls into libusb to do what the "lsusb"
>> sample program does (code copied directly, zero changes).
>> 
>> I will try latest as soon as I can.
>> 
>> Crash log:
>> 
>> 04-11 20:17:03.634: INFO/DEBUG(8870): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
>> 04-11 20:17:03.634: INFO/DEBUG(8870): Build fingerprint: 'google/passion_vf/passion/mahimahi:2.2.1/FRG83D/291266:user/release-keys'
>> 04-11 20:17:03.634: INFO/DEBUG(8870): pid: 10251, tid: 10251  >>> com.darkcorner.android.sutec <<<
>> 04-11 20:17:03.634: INFO/DEBUG(8870): signal 11 (SIGSEGV), fault addr 00000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): r0 00000000  r1 00000003  r2 8080823c  r3 80807114
>> 04-11 20:17:03.634: INFO/DEBUG(8870): r4 ffffef5c  r5 80808138  r6 00000000  r7 0022d338
>> 04-11 20:17:03.634: INFO/DEBUG(8870): r8 be9274f8  r9 4186bcdc  10 4186bcc4  fp 00000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): ip 8080815c  sp be9263e0  lr 808065f9  pc 80801d8c  cpsr 60000030
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d0  643a64696f72646e  d1  6472656767756265
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d2  5363657475532f73  d3  7463417375746174
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d4  0200000801010098  d5  0000000001010036
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d6  1c00000801010099  d7  41600000ffff9200
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d8  0000000000000000  d9  0000000000000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d10 0000000000000000  d11 0000000000000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d12 0000000000000000  d13 0000000000000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d14 0000000000000000  d15 0000000000000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d16 000000070000002b  d17 bff0000000000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d18 3ff0000000000000  d19 0000000000000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d20 0000000000000000  d21 0000000000000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d22 3ff0000000000000  d23 0000000000000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d24 3ff0000000000000  d25 0000000000000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d26 0000000000000000  d27 0000000000000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d28 0000000000000000  d29 0000000000000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): d30 0000000000000000  d31 0000000000000000
>> 04-11 20:17:03.634: INFO/DEBUG(8870): scr 20000012
>> 04-11 20:17:03.664: INFO/DEBUG(8870): #00  pc 00001d8c  /data/data/com.darkcorner.android.sutec/lib/libusb.so
>> 04-11 20:17:03.664: INFO/DEBUG(8870): #01  pc 000065f4  /data/data/com.darkcorner.android.sutec/lib/libusb.so
>> 04-11 20:17:03.664: INFO/DEBUG(8870): #02  pc 00002176  /data/data/com.darkcorner.android.sutec/lib/libusb.so
>> 04-11 20:17:03.664: INFO/DEBUG(8870): #03  pc 0000686a  /data/data/com.darkcorner.android.sutec/lib/libusb.so
>> 04-11 20:17:03.664: INFO/DEBUG(8870): #04  pc 0000688a  /data/data/com.darkcorner.android.sutec/lib/libusb.so
>> 04-11 20:17:03.664: INFO/DEBUG(8870): #05  pc 00010e34  /system/lib/libdvm.so
>> 04-11 20:17:03.664: INFO/DEBUG(8870): #06  pc 0003f2c4  /system/lib/libdvm.so
>> 04-11 20:17:03.664: INFO/DEBUG(8870): #07  pc 000449ea  /system/lib/libdvm.so
>> 04-11 20:17:03.664: INFO/DEBUG(8870): #08  pc 00015d98  /system/lib/libdvm.so
>> 04-11 20:17:03.664: INFO/DEBUG(8870): #09  pc 0001c794  /system/lib/libdvm.so
>> 04-11 20:17:03.674: INFO/DEBUG(8870): #10  pc 0001b634  /system/lib/libdvm.so
>> 04-11 20:17:03.674: INFO/DEBUG(8870): #11  pc 0005678e  /system/lib/libdvm.so
>> 04-11 20:17:03.684: INFO/DEBUG(8870): #12  pc 0005ee58  /system/lib/libdvm.so
>> 04-11 20:17:03.684: INFO/DEBUG(8870): #13  pc 00015d98  /system/lib/libdvm.so
>> 04-11 20:17:03.684: INFO/DEBUG(8870): #14  pc 0001c794  /system/lib/libdvm.so
>> 04-11 20:17:03.684: INFO/DEBUG(8870): #15  pc 0001b634  /system/lib/libdvm.so
>> 04-11 20:17:03.684: INFO/DEBUG(8870): #16  pc 000565cc  /system/lib/libdvm.so
>> 04-11 20:17:03.684: INFO/DEBUG(8870): #17  pc 00041c96  /system/lib/libdvm.so
>> 04-11 20:17:03.684: INFO/DEBUG(8870): #18  pc 0002d894  /system/lib/libandroid_runtime.so
>> 04-11 20:17:03.684: INFO/DEBUG(8870): #19  pc 0002e990  /system/lib/libandroid_runtime.so
>> 04-11 20:17:03.684: INFO/DEBUG(8870): #20  pc 00008ca8  /system/bin/app_process
>> 04-11 20:17:03.684: INFO/DEBUG(8870): #21  pc 0000d3c0  /system/lib/libc.so
>> 04-11 20:17:03.684: INFO/DEBUG(8870): code around pc:
>> 04-11 20:17:03.684: INFO/DEBUG(8870): 80801d6c 6818589b 46c0e7f6 000063da 000000e4
>> 04-11 20:17:03.684: INFO/DEBUG(8870): 80801d7c b530b408 b0824d25 447d1c13 d0412800
>> 04-11 20:17:03.684: INFO/DEBUG(8870): 80801d8c 2a006802 2902d025 2901d00d 2900d032
>> 04-11 20:17:03.684: INFO/DEBUG(8870): 80801d9c 2902d024 2903d009 4c1dd026 592c4a1d
>> 04-11 20:17:03.684: INFO/DEBUG(8870): 80801dac 34a8447a 2a01e006 4c19dd13 592c4a1a
>>

Re: [Libusb-devel] libusb on Android, crash in usbi_log()

From: Hoi-Ho C. <hoi...@gm...> - 2011-04-14 17:50:44

On Thu, Apr 14, 2011 at 10:43 AM, Colin Madere <clm...@ma...> wrote:

> If anyone finds an answer to this, please email me directly since I am now
> moving to a different potential solution and will be dropping off the list
> since I won't be using libusb on the current project (but still am
> interested in a solution).
>
>
Have you tried writing a native program (not using the NDK), push it to your
device via adb, and run it without issue? That might point out where the
problem lies - I've written native apps on Android using libusb without
trouble (but logging is disabled).

As far as I know, Android's bionic might give you slightly differently
behavior on some of the C library functions than uclibc/glibc.

Thanks
Hoi-Ho

Re: [Libusb-devel] libusb on Android, crash in usbi_log()

From: Xiaofan C. <xia...@gm...> - 2011-04-14 23:45:18

On Fri, Apr 15, 2011 at 1:50 AM, Hoi-Ho Chan <hoi...@gm...> wrote:
> On Thu, Apr 14, 2011 at 10:43 AM, Colin Madere <clm...@ma...> wrote:
>>
>> If anyone finds an answer to this, please email me directly since I am now
>> moving to a different potential solution and will be dropping off the list
>> since I won't be using libusb on the current project (but still am
>> interested in a solution).
>>
>
> Have you tried writing a native program (not using the NDK), push it to your
> device via adb, and run it without issue? That might point out where the
> problem lies - I've written native apps on Android using libusb without
> trouble (but logging is disabled).

I heard about this -- logging is disabled for Android libusb. Just
wondering why it is this? Does Android ship with libusb-0.1
and/or libusb-1.0? If not, why do you need to disable logging?

Somebody sent me a private email asking about this and
I asked him to post in the mailing list. Apparently he
has not done that.

> As far as I know, Android's bionic might give you slightly differently
> behavior on some of the C library functions than uclibc/glibc.


-- 
Xiaofan

Re: [Libusb-devel] libusb on Android, crash in usbi_log()

From: Xiaofan C. <xia...@gm...> - 2011-04-14 23:50:07

On Fri, Apr 15, 2011 at 7:45 AM, Xiaofan Chen <xia...@gm...> wrote:
> On Fri, Apr 15, 2011 at 1:50 AM, Hoi-Ho Chan <hoi...@gm...> wrote:
>> On Thu, Apr 14, 2011 at 10:43 AM, Colin Madere <clm...@ma...> wrote:
>>>
>>> If anyone finds an answer to this, please email me directly since I am now
>>> moving to a different potential solution and will be dropping off the list
>>> since I won't be using libusb on the current project (but still am
>>> interested in a solution).
>>>
>>
>> Have you tried writing a native program (not using the NDK), push it to your
>> device via adb, and run it without issue? That might point out where the
>> problem lies - I've written native apps on Android using libusb without
>> trouble (but logging is disabled).
>
> I heard about this -- logging is disabled for Android libusb. Just
> wondering why it is this? Does Android ship with libusb-0.1
> and/or libusb-1.0? If not, why do you need to disable logging?

I mean "if you build libusb-0.1 and libusb-1.0 by yourself,
you can always enable logging, so why do you need to
disable logging?"

> Somebody sent me a private email asking about this and
> I asked him to post in the mailing list. Apparently he
> has not done that.
>
>> As far as I know, Android's bionic might give you slightly differently
>> behavior on some of the C library functions than uclibc/glibc.


-- 
Xiaofan

Re: [Libusb-devel] libusb on Android, crash in usbi_log()

From: Hoi-Ho C. <hoi...@gm...> - 2011-04-15 02:33:12

On Thu, Apr 14, 2011 at 4:45 PM, Xiaofan Chen <xia...@gm...> wrote:

> On Fri, Apr 15, 2011 at 1:50 AM, Hoi-Ho Chan <hoi...@gm...> wrote:
> > On Thu, Apr 14, 2011 at 10:43 AM, Colin Madere <clm...@ma...>
> wrote:
> >>
> >> If anyone finds an answer to this, please email me directly since I am
> now
> >> moving to a different potential solution and will be dropping off the
> list
> >> since I won't be using libusb on the current project (but still am
> >> interested in a solution).
> >>
> >
> > Have you tried writing a native program (not using the NDK), push it to
> your
> > device via adb, and run it without issue? That might point out where the
> > problem lies - I've written native apps on Android using libusb without
> > trouble (but logging is disabled).
>
> I heard about this -- logging is disabled for Android libusb. Just
> wondering why it is this? Does Android ship with libusb-0.1
> and/or libusb-1.0? If not, why do you need to disable logging?
>
>
I'm not so sure if logging is the root cause, because most Android builds
I've played with don't have CONFIG_USB_DEVICEFS enabled in kernel, so most
likely usbfs isn't even mounted.

Thanks
Hoi-Ho

Re: [Libusb-devel] libusb on Android, crash in usbi_log()

From: Xiaofan C. <xia...@gm...> - 2011-04-15 03:29:35

On Fri, Apr 15, 2011 at 10:33 AM, Hoi-Ho Chan <hoi...@gm...> wrote:
> On Thu, Apr 14, 2011 at 4:45 PM, Xiaofan Chen <xia...@gm...> wrote:
>> I heard about this -- logging is disabled for Android libusb. Just
>> wondering why it is this? Does Android ship with libusb-0.1
>> and/or libusb-1.0? If not, why do you need to disable logging?
>>
>
> I'm not so sure if logging is the root cause, because most Android builds
> I've played with don't have CONFIG_USB_DEVICEFS enabled in kernel, so most
> likely usbfs isn't even mounted.

I see. In that case, libusb (0.1 and 1.0) will not work at all.

-- 
Xiaofan

Re: [Libusb-devel] libusb on Android, crash in usbi_log()

From: Alan S. <st...@ro...> - 2011-04-15 14:44:36

On Fri, 15 Apr 2011, Xiaofan Chen wrote:

> On Fri, Apr 15, 2011 at 10:33 AM, Hoi-Ho Chan <hoi...@gm...> wrote:
> > On Thu, Apr 14, 2011 at 4:45 PM, Xiaofan Chen <xia...@gm...> wrote:
> >> I heard about this -- logging is disabled for Android libusb. Just
> >> wondering why it is this? Does Android ship with libusb-0.1
> >> and/or libusb-1.0? If not, why do you need to disable logging?
> >>
> >
> > I'm not so sure if logging is the root cause, because most Android builds
> > I've played with don't have CONFIG_USB_DEVICEFS enabled in kernel, so most
> > likely usbfs isn't even mounted.
> 
> I see. In that case, libusb (0.1 and 1.0) will not work at all.

Libusb-1.0 will work even without CONFIG_USB_DEVICEFS, because it can 
use the device files under /dev/bus/usb/ in addition to /proc/bus/usb/.

Alan Stern

Re: [Libusb-devel] libusb on Android, crash in usbi_log()

From: Xiaofan C. <xia...@gm...> - 2011-04-15 15:32:26

On Fri, Apr 15, 2011 at 10:44 PM, Alan Stern <st...@ro...> wrote:
> On Fri, 15 Apr 2011, Xiaofan Chen wrote:
>> On Fri, Apr 15, 2011 at 10:33 AM, Hoi-Ho Chan <hoi...@gm...> wrote:
>> > I'm not so sure if logging is the root cause, because most Android builds
>> > I've played with don't have CONFIG_USB_DEVICEFS enabled in kernel, so most
>> > likely usbfs isn't even mounted.
>>
>> I see. In that case, libusb (0.1 and 1.0) will not work at all.
>
> Libusb-1.0 will work even without CONFIG_USB_DEVICEFS, because it can
> use the device files under /dev/bus/usb/ in addition to /proc/bus/usb/.

Thanks. I see this option is now deprecated. Maybe I mixed it
up with usbfs support.

-- 
Xiaofan