On Mon, Feb 13, 2012 at 03:01:23PM -0500, Chris Ball wrote: > Hi Don, > > On Mon, Feb 13 2012, Don Zickus wrote: > > Hi Chris, > > > > My name is Don Zickus from Red Hat. I am working with a vendor that would > > like to ship hardware that requires the rts_pstor and rts5139 drivers (two > > different hardware platforms). Before we include them in our RHEL OS, we > > would like to figure what is needed to bump those drivers from 'staging' > > status to something the linux-mmc community would fully support. Is there > > a lot of work to be done or just some style cleanups? Or perhaps you > > haven't really looked at them yet. > > I have had a chance to look at rts_pstor: it's awful, I'm afraid. It > emulates a SCSI device out of the PCI card reader, and it embeds its > own copy of an SD stack inside the driver (in sd.c) behind the scenes > instead of using the kernel's drivers/mmc stack, which is not acceptable. > I don't think there's any future for the driver in mainline until these > complaints are changed; it probably shouldn't even be in staging. > > So, I think that for it to be merged, it must first be rewritten to be > a driver that's a few hundred lines long -- instead of 20,000! -- that > (a) uses Linux's SD stack and (b) exposes MMC devices, not SCSI ones. > That's a fairly complete rewrite, unfortunately, and would only cover > the MMC/SD interface on the hardware -- the same hardware supports > memorystick and xD too, which are different standards/subsystems. > > I had not looked at rts5139, but just took a quick look and it seems > like it's an unmerged duplicate fork of the rts_pstor driver -- another > 20k lines, mostly the same as the ones in rts_pstor, of SCSI emulation > and bundled SD stack, so all of my comments would apply to it too. > > Sorry I don't have better news! I think your best option for mainline > support would be to find a way to offer a long-term loan of systems with > this hardware inside to any volunteers from linux-mmc@ who want to work > on a replacement driver for it; I asked Dell for the same when I learned > they were shipping these devices in laptops, but they don't seem to be > able to loan out laptops for more than a couple of weeks. I did start > out on an rts_pstor rewrite, but wasn't able to get it working before > my temporary access to the hardware ran out. > > (I do wish there were better relationships between the kernel community > and people with new hardware that needs support added for it, such that > we could just file a request with Red Hat, Lenovo or Dell to get access > to shipping hardware with some new chip..) Thanks for the quick reply. I was wondering why the driver seemed so large and now it makes sense. Don't worry about the bad news, it might give us leverage. :-) Your point about hardware access makes sense, though I don't expect it to come out very favorably, I'll poke some people about how to get better at leveraging things for the community. Thanks for your time! Cheers, Don -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
