Linux usb gadget HID driver problem

Sebteams69 · 10-27-2010, 07:31 AM

Hi everybody

I use the linux 2.6.35.4 kernel on an embedded board. The problem is that I want to use the usb gadget HID to connect my board on the PC as a HID device. I compile the kernel with all needed options. The g_hid driver is compile as module. When I do a modprobe g_hid an error is return with no such device.
Can someone help me?
Can someone tell me how the /dev/hidgx is created and which is the major and minor number. I have search in the device.txt file and on Internet but I don't find anything. This driver has been developped in the 2.6.35 kernel version and I don't know if someone use it?

Best regards,
Sebastien

Sebteams69 · 10-27-2010, 11:28 AM

The problem is that I didn't understand the documentation about gadget HID. To solve the problem, you just need to add the two structures in your platform support like the example and add a call to platform_register_device with the device structure as parameter. And then the driver is able to be loaded and is working fine.

Regards,
Sebastien

aManFromOuterSpace · 09-13-2011, 06:37 AM

Quote:

Originally Posted by Sebteams69

The problem is that I didn't understand the documentation about gadget HID. To solve the problem, you just need to add the two structures in your platform support like the example and add a call to platform_register_device with the device structure as parameter. And then the driver is able to be loaded and is working fine.

Regards,
Sebastien

Hate to revive a dead post, but you couldn't point me to the source files that needed modified as well as what the platform_register_device call looks like.

Thanks

aMan

myke.predko · 03-20-2012, 01:09 PM

Like the Man from Outer Space, I don't want to revive a dead post, but if Sebteams69 or anybody else could post some information about implementing a HID device from the Embedded Linux System, I would appreciate it.

Thanx!

myke

ma1 · 05-12-2012, 10:23 AM

Problem Solved.

step1: go to the link below.
http://www.mjmwired.net/kernel/Docum...gadget_hid.txt

step2: copy the following two structures from the above link and paste into hid.c
hidg_func_descriptor
platform_device

step3: compile the hid module

step4: load the module

That's it.

gattusunil · 06-12-2012, 12:13 PM

I tried your suggestion and still ended up with the same issue. Can you give some more details on how to fix this issue?

ma1 · 06-12-2012, 01:00 PM

Quote:

Originally Posted by gattusunil

I tried your suggestion and still ended up with the same issue. Can you give some more details on how to fix this issue?

Hi

In your hidg_init function in the module, call the following

Code:

int status;
status = platform_device_register(&my_hid);
if (status < 0)
{
	platform_driver_unregister(&my_hid);
	return status;
}

where my_hid is a pointer to platform_device struct.

Also call the following function in your hidg_cleanup function

platform_device_unregister(&my_hid);

Hope this will help.

gattusunil · 06-12-2012, 02:24 PM

Thanks for your quicker response. Now, I get the following error. Any ideas?

root@freescale ~$ modprobe g_hid.ko
------------[ cut here ]------------
WARNING: at drivers/base/driver.c:262 driver_unregister+0x30/0x78()
Unexpected driver unregister!
Modules linked in: g_hid(+)
Backtrace:
[<c00344a8>] (dump_backtrace+0x0/0x114) from [<c03ce738>] (dump_stack+0x18/0x1c)
r7:00000009 r6:00000106 r5:c024c5c8 r4:c75a7ee0
[<c03ce720>] (dump_stack+0x0/0x1c) from [<c004c69c>] (warn_slowpath_common+0x54/0x6c)
[<c004c648>] (warn_slowpath_common+0x0/0x6c) from [<c004c758>] (warn_slowpath_fmt+0x38/0x40)
r9:c75a6000 r8:c0030ba8 r7:000072ec r6:00000000 r5:00000000
r4:bf002d08
[<c004c720>] (warn_slowpath_fmt+0x0/0x40) from [<c024c5c8>] (driver_unregister+0x30/0x78)
r3:00000000 r2:c04a8c88
[<c024c598>] (driver_unregister+0x0/0x78) from [<c024d71c>] (platform_driver_unregister+0x14/0x18)
r7:000072ec r6:00000000 r5:00000000 r4:ffffffed
[<c024d708>] (platform_driver_unregister+0x0/0x18) from [<bf00668c>] (hidg_init+0x48/0x64 [g_hid])
[<bf006644>] (hidg_init+0x0/0x64 [g_hid]) from [<c00303bc>] (do_one_initcall+0x64/0x1cc)
r5:00000000 r4:bf006644
[<c0030358>] (do_one_initcall+0x0/0x1cc) from [<c007c14c>] (sys_init_module+0x9c/0x1b8)
r9:c75a6000 r8:c0030ba8 r7:000072ec r6:0009b0b8 r5:00000000
r4:bf002ef0
[<c007c0b0>] (sys_init_module+0x0/0x1b8) from [<c0030a00>] (ret_fast_syscall+0x0/0x2c)
r7:00000080 r6:0009b008 r5:00000000 r4:000072ec
---[ end trace 0cb0ee3e56914919 ]---
modprobe: failed to load module g_hid.ko (/lib/modules/2.6.35.3-571-gcca29a0/kernel/drivers/usb/gadget/g_hid.ko): No such device
root@freescale ~$