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

[Mathieu OTHACEHE <m.othacehe@gmail.com>]

On Sun, Feb 28, 2016 at 01:20:16PM +0100, Johan Hovold wrote:
> 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@gmail.com>
> > > 
> > > 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?

Hi Johan,

No, I don't see any problem to do that. I am testing ti_usb_3410_5052
with support for MOXA 11x0 and almost everything seems fine.
Sorry I didn't noticed it before, it would have saved us some time.

So, I could post a patch serie :

1. Removing mxu11x0 driver
2. Patching ti_usb_3410_5052
3. Cleaning up ti_usb_3410_5052 the same as we cleaned-up mxu11x0

Btw, no response of TI or MOXA about the double opening stuff.

Thank you,
Mathieu