Re: [PATCH v11 5/9] libata: check zero power ready status for ZPODD

[Aaron Lu <aaron.lu@intel.com>]

On 01/08/2013 02:36 AM, Tejun Heo wrote:
> Hello, Aaron.
> 
> On Sun, Jan 06, 2013 at 10:48:25AM +0800, Aaron Lu wrote:
>> +/* Check zero power ready status */
>> +void zpodd_on_suspend(struct ata_device *dev)
>> +{
>> +	struct zpodd *zpodd = dev->zpodd;
>> +	unsigned long expires;
>> +
>> +	if (!zpready(dev)) {
>> +		zpodd->zp_ready = false;
>> +		zpodd->last_ready = 0;
>> +		return;
>> +	}
>> +
>> +	if (!zpodd->last_ready) {
>> +		zpodd->last_ready = jiffies;
>> +		return;
>> +	}
>> +
>> +	expires = zpodd->last_ready +
>> +		  msecs_to_jiffies(zpodd_poweroff_delay * 1000);
>> +	if (time_before(jiffies, expires))
>> +		return;
>> +
>> +	zpodd->zp_ready = true;
>> +}
> 
> Using 0 jiffies as special value is generally considered a bad form.
> It should be mostly ok here but it's not like avoiding that is
> difficult, so let's please not use 0 jiffies as special value.  If you
> have to, add another variable zp_sample_cnt or whatever.

No problem, thanks!

-Aaron