Re: writable mmc profiles actually are writable

[Pat LaVarre <p.lavarre@ieee.org>]

> From: Jens Axboe ...

Thanks again for your immediate & careful review.

> so it works with ide-cd as well

I do have both usb & atapi sample drives to test, I haven't yet tried
atapi.

> Please add ...
> to cdrom.c instead ... GPCMD_GET_CONFIGURATION

Happily will do.  I'll continue to reply as I progress or not.

Before now, I did not know I could find any one place in the kernel
source to tweak CDC decisions.  To my confused newbie eye, ide-cd.c and
sr.c appeared coded independently to fetch mode page x2A Capabilities
and neglect op x46 Get Configuration in slightly different ways.  I
erroneously had planned to develop an ide-cd.c patch after the sr.c
patch.

> Also, make DVD-RAM drives set CDC_MMC_RW ...

Will do.

> ...

Already I have one reaction to share ...

I'm now vague on how we want /proc/sys/dev/cdrom/info to change?

I see:

In -test6 for dvd_ram we have:

Can write CD-R:         0
Can write CD-RW:        0
Can read DVD:           0
Can write DVD-R:        0
Can write DVD-RAM:      1

I ask:

What do we want the new CDC_MMC_RW line to look like?

Should our new line be a CDC_MMC_RW &~ CDC_DVD_RAM line?  That would
give us the same appearance as the last patch I posted i.e. commonly
different devices would provoke only the two exclusive combinations: 

Can write DVD-RAM:      1
Can write other MMC-RW: 0

Can write DVD-RAM:      0
Can write other MMC-RW: 1

Or should our new line look very different, and appear explicitly set
for any CDC_MMC_RW, perhaps:

Tolerates random write: 1

Or do we prefer some other alternative?

Pat LaVarre