Date:   Mon, 27 Feb 2023 21:54:46 +0100
From:   Marc Kleine-Budde <mkl@pengutronix.de>
To:     Oliver Hartkopp <socketcan@hartkopp.net>
Cc:     Arnd Bergmann <arnd@arndb.de>, Arnd Bergmann <arnd@kernel.org>,
        Dominik Brodowski <linux@dominikbrodowski.net>,
        linux-kernel@vger.kernel.org, Bjorn Helgaas <bhelgaas@google.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Hartley Sweeten <hsweeten@visionengravers.com>,
        Ian Abbott <abbotti@mev.co.uk>,
        Jakub Kicinski <kuba@kernel.org>,
        Kevin Cernekee <cernekee@gmail.com>,
        Lukas Wunner <lukas@wunner.de>,
        Manuel Lauss <manuel.lauss@gmail.com>,
        Olof Johansson <olof@lixom.net>,
        Robert Jarzmik <robert.jarzmik@free.fr>,
        YOKOTA Hiroshi <yokota@netlab.is.tsukuba.ac.jp>,
        bcm-kernel-feedback-list@broadcom.com,
        linux-arm-kernel@lists.infradead.org, linux-can@vger.kernel.org,
        linux-mips@vger.kernel.org, linux-pci@vger.kernel.org,
        linux-wireless@vger.kernel.org, Netdev <netdev@vger.kernel.org>
Subject: Re: [RFC 0/6] pcmcia: separate 16-bit support from cardbus
Message-ID: <20230227205446.udsl5tbnzzo4dhi4@pengutronix.de>
References: <20230227133457.431729-1-arnd@kernel.org>
 <1daa9f1f-6a68-273f-0866-72a4496cd0db@hartkopp.net>
 <c5ea695e-8693-4033-9941-c582f1c6f6be@app.fastmail.com>
 <c5f1e652-b7e7-ff79-11e3-8c5c91011b83@hartkopp.net>
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On 27.02.2023 21:32:40, Oliver Hartkopp wrote:
> On 27.02.23 20:53, Arnd Bergmann wrote:
> > On Mon, Feb 27, 2023, at 20:07, Oliver Hartkopp wrote:
>=20
> > > I assume these CAN bus PCMCIA interfaces won't work after your patch
> > > set, right?
> >=20
> > Correct, the patch series in its current form breaks this since
> > your laptop is cardbus compatible. The options I can see are:
> >=20
> > - abandon my series and keep everything unchanged, possibly removing
> >    some of the pcmcia drivers that Dominik identified as candidates
> >=20
> > - decide on a future timeline for when you are comfortable with
> >    discontinuing this setup and require any CAN users with cardbus
> >    laptops to move to USB or cardbus CAN adapters, apply the series
> >    then
> >=20
> > - duplicate the yenta_socket driver to have two variants of that,
> >    require the user to choose between the cardbus and the pcmcia
> >    variant depending on what card is going to be used.
> >=20
> > Can you give more background on who is using the EMS PCMCIA card?
> > I.e. are there reasons to use this device on modern kernels with
> > machines that could also support the USB, expresscard or cardbus
> > variants, or are you likely the only one doing this for the
> > purpose of maintaining the driver?
>=20
> Haha, good point.
>=20
> In fact the EMS PCMCIA, the PEAK PCMCIA (PCAN PC Card) and the supported
> Softing PCMCIA cards are nearly 20 year old designs and they are all
> discontinued for some time now. Today you can easily get a high performan=
ce
> Classical CAN USB adapter with an excellent OSS firmware for ~13 EUR.
>=20
> The only other laptop CAN "Cards" I'm aware of are PCIe "ExpressCard" 34/=
54
> from PEAK System which use the PCI subsystem.
>=20
> Maybe you are right and we should simply drop the support for those old
> PCMCIA drivers which will still be supported for the LTS 6.1 lifetime the=
n.
>=20
> @Marc Kleine-Budde: What do you think about removing these three drivers?

I don't have any of these cards, nor any $CUSTOMER who's using it.

Marc

--=20
Pengutronix e.K.                 | Marc Kleine-Budde           |
Embedded Linux                   | https://www.pengutronix.de  |
Vertretung West/Dortmund         | Phone: +49-231-2826-924     |
Amtsgericht Hildesheim, HRA 2686 | Fax:   +49-5121-206917-5555 |

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