Re: Re: [PATCH v2] HID: i2c-hid: Fixes "(null)" device name error logs in i2c_hid_parse

Re: Re: [PATCH v2] HID: i2c-hid: Fixes "(null)" device name error logs in i2c_hid_parse

[Ai Chao]

Hello Doug

"Ai" is my surname, and "Chao" is my given name. My name is Ai Chao, which translates to "Super AI".

> > Before: hid (null): reading report descriptor failed
> > After:  i2c_hid i2c-TPD0001:00: reading report descriptor failed
> >
> > Signed-off-by: Ai Chao <aichao@kylinos.cn>
> > ---
> > change for v2
> > - Used Fixes tag.

> Could have fooled me. ;-)

syslog:
kernel: [    3.815131][ 1] [  T319] i2c_designware HYGO0010:00: timeout in disabling adapter
kernel: [   15.790171][ 1] [  T319] i2c_designware HYGO0010:00: timeout waiting for bus ready
kernel: [   15.998769][ 1] [  T319] i2c reading report descriptor failed retry:49
kernel: [   16.038176][ 1] [  T319] i2c_designware HYGO0010:00: timeout waiting for bus ready
kernel: [   16.246771][ 1] [  T319] i2c reading report descriptor failed retry:50
kernel: [   16.246775][ 1] [  T319] hid (null): reading report descriptor failed
kernel: [   16.246778][ 1] [  T319] i2c_hid i2c-TPD0001:00: can't add hid device: -5
kernel: [   16.246954][ 1] [  T319] i2c_hid: probe of i2c-TPD0001:00 failed with error -5


Thanks,
Ai Chao

Re: [PATCH v2] HID: i2c-hid: Fixes "(null)" device name error logs in i2c_hid_parse

[Mario Limonciello]

On 7/9/26 21:39, Ai Chao wrote:
> Hello Doug
> 
> "Ai" is my surname, and "Chao" is my given name. My name is Ai Chao, which translates to "Super AI".
> 
>>> Before: hid (null): reading report descriptor failed
>>> After:  i2c_hid i2c-TPD0001:00: reading report descriptor failed
>>>
>>> Signed-off-by: Ai Chao <aichao@kylinos.cn>
>>> ---
>>> change for v2
>>> - Used Fixes tag.
> 
>> Could have fooled me. ;-)
> 
> syslog:
> kernel: [    3.815131][ 1] [  T319] i2c_designware HYGO0010:00: timeout in disabling adapter
> kernel: [   15.790171][ 1] [  T319] i2c_designware HYGO0010:00: timeout waiting for bus ready
> kernel: [   15.998769][ 1] [  T319] i2c reading report descriptor failed retry:49
> kernel: [   16.038176][ 1] [  T319] i2c_designware HYGO0010:00: timeout waiting for bus ready
> kernel: [   16.246771][ 1] [  T319] i2c reading report descriptor failed retry:50
> kernel: [   16.246775][ 1] [  T319] hid (null): reading report descriptor failed
> kernel: [   16.246778][ 1] [  T319] i2c_hid i2c-TPD0001:00: can't add hid device: -5
> kernel: [   16.246954][ 1] [  T319] i2c_hid: probe of i2c-TPD0001:00 failed with error -5
> 
> 
> Thanks,
> Ai Chao
> 
> 

The point was that there is no "Fixes" tag added above your SoB, but you 
mentioned that there was one in your changelist.  Identify the commit 
that you're fixing (use git blame for example) and then add it to the 
commit text above your SoB in the correct format.

# git log -1 --format='Fixes: %h ("%s")' $commit

[PATCH v2] HID: i2c-hid: Fixes "(null)" device name error logs in i2c_hid_parse

[Ai Chao]

When i2c-hid fails to read the HID report descriptor during device
initialization, the error message prints as:

  hid (null): reading report descriptor failed

The HID device name is set in hid_add_device() after calling
hdev->ll_driver->parse(), so when i2c_hid_parse() fails and calls
hid_err(), the device name has not been set yet, resulting in "(null)"
output.

Use dev_err(&client->dev, ...) instead of hid_err(hid, ...) because
the I2C client device is fully initialized with a proper name, providing
meaningful error messages for debugging.

Before: hid (null): reading report descriptor failed
After:  i2c_hid i2c-TPD0001:00: reading report descriptor failed

Signed-off-by: Ai Chao <aichao@kylinos.cn>
---
change for v2
- Used Fixes tag.
---
 drivers/hid/i2c-hid/i2c-hid-core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
index 3adb16366e93..0e725a0f0abe 100644
--- a/drivers/hid/i2c-hid/i2c-hid-core.c
+++ b/drivers/hid/i2c-hid/i2c-hid-core.c
@@ -792,7 +792,7 @@ static int i2c_hid_parse(struct hid_device *hid)
 					    ihid->hdesc.wReportDescRegister,
 					    rdesc, rsize);
 		if (ret) {
-			hid_err(hid, "reading report descriptor failed\n");
+			dev_err(&client->dev, "reading report descriptor failed\n");
 			goto out;
 		}
 	}
-- 
2.34.1

Re: [PATCH v2] HID: i2c-hid: Fixes "(null)" device name error logs in i2c_hid_parse

[Doug Anderson]

Hi,

On Mon, Jul 6, 2026 at 6:54 PM Ai Chao <aichao@kylinos.cn> wrote:
>
> When i2c-hid fails to read the HID report descriptor during device
> initialization, the error message prints as:
>
>   hid (null): reading report descriptor failed
>
> The HID device name is set in hid_add_device() after calling
> hdev->ll_driver->parse(), so when i2c_hid_parse() fails and calls
> hid_err(), the device name has not been set yet, resulting in "(null)"
> output.
>
> Use dev_err(&client->dev, ...) instead of hid_err(hid, ...) because
> the I2C client device is fully initialized with a proper name, providing
> meaningful error messages for debugging.
>
> Before: hid (null): reading report descriptor failed
> After:  i2c_hid i2c-TPD0001:00: reading report descriptor failed
>
> Signed-off-by: Ai Chao <aichao@kylinos.cn>
> ---
> change for v2
> - Used Fixes tag.

Could have fooled me. ;-)

-Doug