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Subject: Re: [RFC 1/1] s390/pci: expose a PCI device's UID as its index
To:     =?UTF-8?Q?Krzysztof_Wilczy=c5=84ski?= <kw@linux.com>
Cc:     Bjorn Helgaas <helgaas@kernel.org>,
        Narendra K <narendra_k@dell.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Viktor Mihajlovski <mihajlov@linux.ibm.com>,
        Stefan Raspl <raspl@linux.ibm.com>,
        Peter Oberparleiter <oberpar@linux.ibm.com>,
        linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-s390@vger.kernel.org
References: <20210303095250.1360007-1-schnelle@linux.ibm.com>
 <20210303095250.1360007-2-schnelle@linux.ibm.com>
 <YEU7iFjxNxQK3ldc@rocinante>
From:   Niklas Schnelle <schnelle@linux.ibm.com>
Message-ID: <c714ca55-7189-e196-7b8d-f02da555b399@linux.ibm.com>
Date:   Mon, 8 Mar 2021 08:02:07 +0100
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On 3/7/21 9:46 PM, Krzysztof Wilczyński wrote:
> Hi Niklas,
> 
> [...]
>> +static ssize_t index_show(struct device *dev,
>> +			  struct device_attribute *attr, char *buf)
>> +{
>> +	struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
>> +	u32 index = ~0;
>> +
>> +	if (zpci_unique_uid)
>> +		index = zdev->uid;
>> +
>> +	return sprintf(buf, "%u\n", index);
> [...]
> 
> Would it be possible to use the new sysfs_emit() rather than sprintf()
> even though the zpci_attr macro and still use mio_enabled_show() still
> would use sprintf().  What do you think?
> 
> See https://www.kernel.org/doc/html/latest/filesystems/sysfs.html for
> the changes in the internal API.
> 
> Krzysztof
> 

Of course that makes sense and thanks for pointing me to this API!
@Viktor, may I carry your R-b over?

I'll also update the other attributes in a clean up patch.

Thanks,
Niklas