Re: [PATCH v4] hwmon: add POWER-Z driver

[Guenter Roeck <linux@roeck-us.net>]

On 9/2/23 22:54, Douglas Gilbert wrote:
> On 2023-09-02 18:56, Guenter Roeck wrote:
>> On 9/2/23 15:29, Thomas Weißschuh wrote:
>>> Hi,
>>>
>>> On 2023-09-02 18:36:17+0200, Christophe JAILLET wrote:
>>>> Le 02/09/2023 à 09:47, Thomas Weißschuh a écrit :
>>>>> POWER-Z is a series of devices to monitor power characteristics of
>>>>> USB-C connections and display those on a on-device display.
>>>>> Some of the devices, notably KM002C and KM003C, contain an additional
>>>>> port which exposes the measurements via USB.
>>>>>
>>>>> This is a driver for this monitor port.
>>>>>
>>>>> It was developed and tested with the KM003C.
>>>>>
>>>>> Signed-off-by: Thomas Weißschuh <linux-9XfqOkM5JgxKQ7RDE2T8Pw@public.gmane.org>
>>>>> ---
>>>>
>>>> ...
>>>>
>>>>> +static int powerz_probe(struct usb_interface *intf,
>>>>> +            const struct usb_device_id *id)
>>>>> +{
>>>>> +    struct powerz_priv *priv;
>>>>> +    struct device *hwmon_dev;
>>>>> +    struct device *parent;
>>>>> +
>>>>> +    parent = &intf->dev;
>>>>> +
>>>>> +    priv = devm_kzalloc(parent, sizeof(*priv), GFP_KERNEL);
>>>>> +    if (!priv)
>>>>> +        return -ENOMEM;
>>>>> +
>>>>> +    priv->urb = usb_alloc_urb(0, GFP_KERNEL);
>>>>> +    if (!priv->urb)
>>>>> +        return -ENOMEM;
>>>>> +    mutex_init(&priv->mutex);
>>>>> +    priv->status = -ETIMEDOUT;
>>>>> +    init_completion(&priv->completion);
>>>>> +
>>>>> +    hwmon_dev =
>>>>> +        devm_hwmon_device_register_with_info(parent, DRIVER_NAME, priv,
>>>>> +                         &powerz_chip_info, NULL);
>>>>> +    usb_set_intfdata(intf, priv);
>>>>> +
>>>>> +    return PTR_ERR_OR_ZERO(hwmon_dev);
>>>>
>>>> Hi,
>>>>
>>>> If 'hwmon_dev' is an PTR_ERR, priv->urb leaks.
>>>
>>> Good catch, thanks!
>>>
>>>
>>> Guenter,
>>>
>>> it seems the new hwmon-next with this driver has not yet been pushed to
>>> git.kernel.org, so I can't generate the Fixes tag.
>>>
>>
>> Rule is that I must not push anything into linux-next until
>> after v6.6-rc1 has been released.
>>
>>> Can you modify the commit to also contain the changes below?
>>> Or let me know if you prefer something else.
>>>
>>
>> I'll update the patch and make the change.
> 
> Hi,
> While you are at it, you can make the driver detect the earlier model KM002C:
> 

Please send a separate patch to do that.

Thanks,
Guenter

> --- powerz.c_orig    2023-09-02 13:47:14.754705791 -0400
> +++ powerz.c    2023-09-02 23:22:54.783856587 -0400
> @@ -250,6 +250,7 @@
> 
>   static const struct usb_device_id powerz_id_table[] = {
>       { USB_DEVICE_INTERFACE_NUMBER(0x5FC9, 0x0063, 0x00) },    /* ChargerLAB POWER-Z KM003C */
> +    { USB_DEVICE_INTERFACE_NUMBER(0x5FC9, 0x0061, 0x00) },    /* ChargerLAB POWER-Z KM002C */
>       { }
>   };
> 
> Do you want a "Tested-by" on the patch as well?
> 
> Doug Gilbert
> 
>