On Fri, Apr 17, 2015 at 09:35:46PM -0400, Dan Williams wrote: > This is the position (device topology) independent method to find all > the NFIT-defined buses in the system. The expectation is that there > will only ever be one "nd" bus discovered via /sys/class/nd/ndctl0. > However, we allow for the possibility of multiple buses and they will > listed in discovery order as ndctl0...ndctlN. This character device > hosts the ioctl for passing control messages (as defined by the NFIT > spec). The "format" and "revision" attributes of this device identify > the format of the messages. In the event an NFIT is registered with an > unknown/unsupported control message format then the "format" attribute > will not be visible. > > Cc: Greg KH <gre...@linuxfoundation.org> > Cc: Neil Brown <ne...@suse.de> > Signed-off-by: Dan Williams <dan.j.willi...@intel.com> > --- > drivers/block/nd/Makefile | 1 > drivers/block/nd/bus.c | 84 > +++++++++++++++++++++++++++++++++++++++++ > drivers/block/nd/core.c | 71 ++++++++++++++++++++++++++++++++++- > drivers/block/nd/nd-private.h | 5 ++ > 4 files changed, 160 insertions(+), 1 deletion(-) > create mode 100644 drivers/block/nd/bus.c > > diff --git a/drivers/block/nd/Makefile b/drivers/block/nd/Makefile > index c6bec0c185c5..7772fb599809 100644 > --- a/drivers/block/nd/Makefile > +++ b/drivers/block/nd/Makefile > @@ -20,3 +20,4 @@ obj-$(CONFIG_NFIT_ACPI) += nd_acpi.o > nd_acpi-y := acpi.o > > nd-y := core.o > +nd-y += bus.o > diff --git a/drivers/block/nd/bus.c b/drivers/block/nd/bus.c > new file mode 100644 > index 000000000000..c27db50511f2 > --- /dev/null > +++ b/drivers/block/nd/bus.c > @@ -0,0 +1,84 @@ > +/* > + * Copyright(c) 2013-2015 Intel Corporation. All rights reserved. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of version 2 of the GNU General Public License as > + * published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, but > + * WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + * General Public License for more details. > + */ > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > +#include <linux/uaccess.h> > +#include <linux/fcntl.h> > +#include <linux/slab.h> > +#include <linux/fs.h> > +#include <linux/io.h> > +#include "nd-private.h" > +#include "nfit.h" > + > +static int nd_major; > +static struct class *nd_class; > + > +int nd_bus_create_ndctl(struct nd_bus *nd_bus) > +{ > + dev_t devt = MKDEV(nd_major, nd_bus->id); > + struct device *dev; > + > + dev = device_create(nd_class, &nd_bus->dev, devt, nd_bus, "ndctl%d", > + nd_bus->id); > + > + if (IS_ERR(dev)) { > + dev_dbg(&nd_bus->dev, "failed to register ndctl%d: %ld\n", > + nd_bus->id, PTR_ERR(dev)); > + return PTR_ERR(dev); > + } > + return 0; > +} > + > +void nd_bus_destroy_ndctl(struct nd_bus *nd_bus) > +{ > + device_destroy(nd_class, MKDEV(nd_major, nd_bus->id)); > +} > + > +static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) > +{ > + return -ENXIO; > +}
There is no ioctl call here, so why even have this character device? thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/