Subject: Re: [PATCH] net: dsa: set parent of hwmon device

From: Guenter Roeck <[email-masked]>
Date: Tue, 20 Jan 2015 19:50:54 -0800

On 01/20/2015 04:13 PM, Vivien Didelot wrote:
> Set the dsa device as the parent of the hwmon device, in order to link
> the hwmon subsystem under the corresponding /sys/devices/platform/dsa.X/
> sysfs directory.
>
> Signed-off-by: Vivien Didelot <[email-masked]>
> ---
>   net/dsa/dsa.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
> index 3731714..363102a 100644
> --- a/net/dsa/dsa.c
> +++ b/net/dsa/dsa.c
> @@ -347,7 +347,7 @@ dsa_switch_setup(struct dsa_switch_tree *dst, int index,
>   		hname[j] = '\0';
>   		scnprintf(ds->hwmon_name, sizeof(ds->hwmon_name), "%s_dsa%d",
>   			  hname, index);
> -		ds->hwmon_dev = hwmon_device_register_with_groups(NULL,
> +		ds->hwmon_dev = hwmon_device_register_with_groups(parent,
>   					ds->hwmon_name, ds, dsa_hwmon_groups);
>   		if (IS_ERR(ds->hwmon_dev))
>   			ds->hwmon_dev = NULL;
>

Looking into my old e-mail, turns out we did not add the parent device because
it affected the output of the "sensors" command, and we wanted the device
to be handled as 'virtual device' (which implies no parent). That was an explicit
part of the patch set (v2 of 'net: dsa: Add support for reporting switch chip
temperatures'), compared to v1, which did set the parent device.

I would suggest to keep the code as is.

Thanks,
Guenter