Messages in this thread |  | | From | Arnd Bergmann <> | Subject | Re: [PATCH] char/pcmcia: add scr24x_cs chip card interface driver | Date | Mon, 10 Oct 2016 21:24:10 +0200 |
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On Monday, October 10, 2016 7:33:45 PM CEST Greg Kroah-Hartman wrote: > > + > > +#define SCR24X_DEVS 8 > > +static DECLARE_BITMAP(scr24x_minors, SCR24X_DEVS); > > + > > +static struct class *scr24x_class; > > +dev_t scr24x_devt; > > global variable? And why do you need a char device for this type of > hardware? Isn't there already an existing interface for this device > class?
It looks like this is modeled after the other two chip card drivers in drivers/char/pcmcia/, which are also char devices. Looking at https://pcsclite.alioth.debian.org/ccid.html, it seems that other drivers for this protocol are typically in user space when they are for USB devices, so apparently no existing subsystem abstraction in the kernel.
This reminds me that there is just one other driver in drivers/char/pcmcia (synclink_cs), and that should be moved to drivers/tty/ with the other synclink variants. If we do this, we could rename drivers/char/pcmcia to something that implies "smartcard".
Arnd
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