RE: [PATCH] clkdev: Update clkdev id usage to allow for longer names

From: Ruhl, Michael J
Date: Fri Feb 23 2024 - 11:10:26 EST


>-----Original Message-----
>From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
>Sent: Friday, February 23, 2024 10:48 AM
>To: Ruhl, Michael J <michael.j.ruhl@xxxxxxxxx>
>Cc: linux@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-
>kernel@xxxxxxxxxxxxxxx
>Subject: Re: [PATCH] clkdev: Update clkdev id usage to allow for longer names
>
>On Fri, Feb 23, 2024 at 09:18:14AM -0500, Michael J. Ruhl wrote:
>> clkdev ID information is limited to arrays of 20 and 16 bytes
>> (MAX_DEV_ID/MAX_CON_ID). It is possible that the IDs could be
>> longer that. If so, the lookup will fail because the "real ID"
>> will not match the copied value.
>
>Perhaps you need to add a real example.

How about:

Generating a device name for the I2C Designware module using the PCI
ID can result in a name of:

i2c_designware.39424

clkdev_create will store:

i2c_designware.3942

The stored name is one off and will not match correctly during probe.

>> Increase the size of the IDs to allow for longer names.
>
>...
>
>> -#define MAX_DEV_ID 20
>> -#define MAX_CON_ID 16
>> +#define MAX_DEV_ID 32
>> +#define MAX_CON_ID 32
>
>Do we need to alter both?

It wasn't clear to why there was a difference in sizes. At the moment the CON_ID isn't
causing me an issue. Shall I drop that part of the change?

Thanks!

Mike

>--
>With Best Regards,
>Andy Shevchenko
>