> -----Original Message----- > From: Greg KH [mailto:gregkh@xxxxxxxxxxxxxxxxxxx] > Sent: Sunday 9 June 2019 12:23 > To: Dragan Cvetic <draganc@xxxxxxxxxx> > Cc: arnd@xxxxxxxx; Michal Simek <michals@xxxxxxxxxx>; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; robh+dt@xxxxxxxxxx; > mark.rutland@xxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Derek Kiernan <dkiernan@xxxxxxxxxx> > Subject: Re: [PATCH V5 02/11] misc: xilinx-sdfec: add core driver > > On Sun, Jun 09, 2019 at 01:04:07AM +0100, Dragan Cvetic wrote: > > Implement a platform driver that matches with xlnx, > > sd-fec-1.1 device tree node and registers as a character > > device, including: > > - SD-FEC driver binds to sdfec DT node. > > - creates and initialise an initial driver dev structure. > > - add the driver in Linux build and Kconfig. > > > > Tested-by: Dragan Cvetic <dragan.cvetic@xxxxxxxxxx> > > Signed-off-by: Derek Kiernan <derek.kiernan@xxxxxxxxxx> > > Signed-off-by: Dragan Cvetic <dragan.cvetic@xxxxxxxxxx> > > --- > > drivers/misc/Kconfig | 12 +++++ > > drivers/misc/Makefile | 1 + > > drivers/misc/xilinx_sdfec.c | 118 ++++++++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 131 insertions(+) > > create mode 100644 drivers/misc/xilinx_sdfec.c > > > > diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig > > index 6b0417b..319a6bf 100644 > > --- a/drivers/misc/Kconfig > > +++ b/drivers/misc/Kconfig > > @@ -471,6 +471,18 @@ config PCI_ENDPOINT_TEST > > Enable this configuration option to enable the host side test driver > > for PCI Endpoint. > > > > +config XILINX_SDFEC > > + tristate "Xilinx SDFEC 16" > > + help > > + This option enables support for the Xilinx SDFEC (Soft Decision > > + Forward Error Correction) driver. This enables a char driver > > + for the SDFEC. > > + > > + You may select this driver if your design instantiates the > > + SDFEC(16nm) hardened block. To compile this as a module choose M. > > + > > + If unsure, say N. > > + > > config MISC_RTSX > > tristate > > default MISC_RTSX_PCI || MISC_RTSX_USB > > diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile > > index b9affcd..0cb3546 100644 > > --- a/drivers/misc/Makefile > > +++ b/drivers/misc/Makefile > > @@ -59,3 +59,4 @@ obj-$(CONFIG_OCXL) += ocxl/ > > obj-y += cardreader/ > > obj-$(CONFIG_PVPANIC) += pvpanic.o > > obj-$(CONFIG_HABANA_AI) += habanalabs/ > > +obj-$(CONFIG_XILINX_SDFEC) += xilinx_sdfec.o > > diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c > > new file mode 100644 > > index 0000000..75cc980 > > --- /dev/null > > +++ b/drivers/misc/xilinx_sdfec.c > > @@ -0,0 +1,118 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Xilinx SDFEC > > + * > > + * Copyright (C) 2019 Xilinx, Inc. > > + * > > + * Description: > > + * This driver is developed for SDFEC16 (Soft Decision FEC 16nm) > > + * IP. It exposes a char device which supports file operations > > + * like open(), close() and ioctl(). > > + */ > > + > > +#include <linux/miscdevice.h> > > +#include <linux/io.h> > > +#include <linux/interrupt.h> > > +#include <linux/kernel.h> > > +#include <linux/module.h> > > +#include <linux/of_platform.h> > > +#include <linux/poll.h> > > +#include <linux/slab.h> > > +#include <linux/clk.h> > > + > > +static int xsdfec_ndevs; > > You should use an idr for this, not just a number you bump up and down. > This will not work properly at all. > > Think about this situation: > probe device 0 > xsdfec_ndevs = 1 > probe device 1 > xsdfec_ndevs = 2 > remove device 0 > xsdfec_ndevs = 0 > probe another device > misc device fails due to duplicate name. > My bad. I can use idr, but couldn't be better optimized code if use simple mutex to protect the variable. > thanks, > > greg k-h
