Re: [PATCH] libata test-unit-ready for ATAPI devices

[Jeff Garzik <jgarzik@pobox.com>]

Willem Riede wrote:
> On Wed, 16 Nov 2005 07:46:28 -0500, Jeff Garzik wrote:
> 
> 
>>Tejun Heo wrote:
>>
>>>On Tue, Nov 15, 2005 at 11:48:41PM -0500, Jeff Garzik wrote:
>>>
>>>
>>>>The following patch clears the "I was just reset" condition from an
>>>>ATAPI device, and waits for it to come online, before continuing with
>>>>the probe.
>>>>
>>>>Not checking this into any upstream-bound branch, as I'm not yet
>>>>convinced of its value.
>>>
>>>
>>>How about the following one?  It doesn't make libata wait for the
>>>device to become ready before trying to configure ATA stuff.  It just
>>>makes sr wait for the device to become ready before performing SCSI
>>>configuration.  Maybe both are needed?
>>
>>[thinking out loud]  My rationale for doing TUR in libata was to clear 
>>the UNIT ATTENTION that libata caused through software/hardware reset. 
>>Once the UNIT ATTENTION was cleared, my rationale for waiting for the 
>>NOT READY(BECOMING READY) condition was simply symmetry with other 
>>libata probe tasks, which similarly wait for device readiness.
>>
>>However, given that sr is already coded to clear "the initial startup 
>>UNIT_ATTENTION", I tend to think your patch is more appropriate, and my 
>>patch should not be applied at all.
> 
> 
> I don't know when this code would get executed - if it is only at boot I
> don't mind, but other than that, in the osst driver, I need to know if the


This is only at boot.

	Jeff