Re: [PATCH v2 1/4] USB: mxu11x0: fix memory leak on usb_serial private data

From: Johan Hovold
Date: Sun Feb 28 2016 - 07:20:17 EST

On Sat, Jan 30, 2016 at 06:40:30PM +0100, Mathieu OTHACEHE wrote:
> On Mon, Jan 25, 2016 at 01:01:59PM +0100, Johan Hovold wrote:
> > On Mon, Jan 04, 2016 at 07:49:36PM +0100, Mathieu OTHACEHE wrote:
> > > On nominal execution, private data allocated on port_probe and attach
> > > are never freed. Add port_remove and release callbacks to free them
> > > respectively.
> > >
> > > Signed-off-by: Mathieu OTHACEHE <m.othacehe@xxxxxxxxx>
> >
> > I've applied this one for 4.5-rc2 now.
> >
> > I want to take a closer look at the last three patches and it seems they
> > should wait for 4.6 anyway. I did notice that the vendor driver also
> > sends double START/OPEN commands at open by the way. Perhaps ask Moxa
> > why that is before we remove them?
> >
> > Thanks,
> > Johan
> Hi Johan,
> I asked MOXA about this double opening. I also noticed that the
> mainline driver ti_usb_3410_5052 uses the same double opening pattern.
> And, MOXA UPORT 11x0 serie is based on TUSB3410 chip of TI.
> So, I also emailed TI, and the authors of ti_usb_3410_5052 driver.

Wow, this is embarrassing. I only now noticed that the mxu11x0 driver,
well at least prior to all your clean-ups, is almost identical to the
ti_usb_3410_5052 driver, and here I see you mention that it is indeed
based on the same chip.

I wish that this had been made clear from the outset. We don't want two
drivers for the same chip if we can avoid it. Instead we should try to
merge these changes back to the ti_usb_3410_5052 driver and clean that
up instead.

Do you see anything preventing us from using the ti_usb_3410_5052
driver for these Moxa devices?