Dell XPS 13 9370: Linux warns `i2c_hid_acpi i2c-ELAN24EE:00: i2c_hid_get_input: IRQ triggered but there's no data`

Dear Linux folks,


On the Dell XPS 13 9370/0F6P3V, BIOS 1.21.0 07/06/2022, Debian’s Linux 
6.9.12 warns:

     i2c_hid_acpi i2c-ELAN24EE:00: i2c_hid_get_input: IRQ triggered but 
there's no data

What can be done about this warning? Looking at commit 1475af255e18 
(HID: i2c-hid: Ignore input report if there's no data present on Elan 
touchpanels), printing the warning is intentional for all ELAN human 
input devices.

While using Elan touchpads, the message floods:
[  136.138487] i2c_hid i2c-DELL08D6:00: i2c_hid_get_input: incomplete report (14/65535)

Though the message flood is annoying, the device it self works without
any issue. I suspect that the device in question takes too much time to
pull the IRQ back to high after I2C host has done reading its data.

Since the host receives all useful data, let's ignore the input report
when there's no data.

`include/linux/kern_levels.h` defines:

     #define KERN_WARNING    KERN_SOH "4"    /* warning conditions */
     #define KERN_NOTICE     KERN_SOH "5"    /* normal but significant 
condition */

As the condition seems normal, and there is no hint, what the user can 
do about the warning, like to contact ELAN, I’d reduce the log level?


Kind regards,

Paul


[1]: 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1475af255e18f35dc46f8a7acc18354c73d45149