Re: [PATCH] soc: qcom: cmd-db: fix minor version decoding in debugfs output

[Sneh Mankad <sneh.mankad@oss.qualcomm.com>]

On 30-Mar-26 12:41 AM, Alok Tiwari wrote:
> cmd-db encodes the version as major in the high byte and minor in the low
> byte. cmd_db_debugfs_dump() prints the full 16 bit value as the minor
> version, resulting in incorrect output.
>
> Extract minor from the low byte using (version & 0xff).
>
> Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
There should be a "fixes:" tag added since this is a fix.
> ---
>   drivers/soc/qcom/cmd-db.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/soc/qcom/cmd-db.c b/drivers/soc/qcom/cmd-db.c
> index 84a75d8c4b70..eed7013c7676 100644
> --- a/drivers/soc/qcom/cmd-db.c
> +++ b/drivers/soc/qcom/cmd-db.c
> @@ -301,7 +301,7 @@ static int cmd_db_debugfs_dump(struct seq_file *seq, void *p)
>   
>   		version = le16_to_cpu(rsc->version);
>   		major = version >> 8;
> -		minor = version;
> +		minor = version & 0xff;

Minor is already a u8 type, so assigning a u16 type version to u8 type 
will automatically truncate the higher 8 bits.

Its the same reason why version is right shifted by 8 before being 
assigned to major variable.

I do not think there would be any difference in output with or without 
the change, do you have any example?

Thanks,
Sneh Mankad

>   
>   		seq_printf(seq, "Slave %s (v%u.%u)\n", name, major, minor);
>   		seq_puts(seq, "-------------------------\n");