Thanks for review Greg,
> -----Original Message-----
> From: Greg KH [mailto:gre...@linuxfoundation.org]
> Sent: Tuesday, January 23, 2018 12:38 AM
> To: Jolly Shah <jol...@xilinx.com>
> Cc: ard.biesheu...@linaro.org; mi...@kernel.org; m...@codeblueprint.co.uk;
> sudeep.ho...@arm.com; hkallwe...@gmail.com; keesc...@chromium.org;
> dmitry.torok...@gmail.com; michal.si...@xilinx.com; robh...@kernel.org;
> mark.rutl...@arm.com; linux-arm-ker...@lists.infradead.org; linux-
> ker...@vger.kernel.org; devicet...@vger.kernel.org; Rajan Vaja
> <raj...@xilinx.com>; Jolly Shah <jol...@xilinx.com>
> Subject: Re: [PATCH v2 3/4] drivers: firmware: xilinx: Add sysfs interface
>
> On Wed, Jan 17, 2018 at 12:20:33PM -0800, Jolly Shah wrote:
> > Add Firmware-ggs sysfs interface which provides read/write interface
> > to global storage registers.
> >
> > Signed-off-by: Jolly Shah <jol...@xilinx.com>
> > Signed-off-by: Rajan Vaja <raj...@xilinx.com>
> > ---
> > .../ABI/stable/sysfs-driver-zynqmp-firmware | 33 +++
> > drivers/firmware/xilinx/zynqmp/Makefile | 2 +-
> > drivers/firmware/xilinx/zynqmp/firmware-ggs.c | 298
> +++++++++++++++++++++
> > drivers/firmware/xilinx/zynqmp/firmware.c | 26 ++
> > include/linux/firmware/xilinx/zynqmp/firmware.h | 2 +
> > 5 files changed, 360 insertions(+), 1 deletion(-) create mode 100644
> > Documentation/ABI/stable/sysfs-driver-zynqmp-firmware
> > create mode 100644 drivers/firmware/xilinx/zynqmp/firmware-ggs.c
> >
> > +
> > +#include <linux/firmware/xilinx/zynqmp/firmware.h>
>
> That's crazy deep nesting, why?
It needs to be in include/linux to be used by other drivers and as it is Xilinx
specific, we have it in subdirectory.
>
> > +
> > +static ssize_t read_register(char *buf, u32 ioctl_id, u32 reg) {
> > + int ret;
> > + u32 ret_payload[PAYLOAD_ARG_CNT];
> > + const struct zynqmp_eemi_ops *eemi_ops = get_eemi_ops();
> > +
> > + if (!eemi_ops || !eemi_ops->ioctl)
> > + return 0;
>
> Not an error?
Fixed in v3 patch series.
>
> > +
> > + ret = eemi_ops->ioctl(0, ioctl_id, reg, 0, ret_payload);
> > + if (ret)
> > + return ret;
> > +
> > + return snprintf(buf, PAGE_SIZE, "0x%x\n", ret_payload[1]);
>
> Minor nit, you never need to use snprintf() for a sysfs file, as you "know"
> the size
> and you can't overflow it with just a single value.
>
> Yeah, some tool-checkers hate to see a "raw" sprintf() call, but really,
> ignore
> them here :)
Changed to sprint in v3 patch series.
> > +
> > + /* Read the write value */
> > + tok = strsep(&inbuf, " ");
> > + if (!tok) {
> > + ret = -EFAULT;
> > + goto err;
> > + }
> > +
> > + ret = kstrtol(tok, 16, &value);
> > + if (ret) {
> > + ret = -EFAULT;
> > + goto err;
> > + }
>
> What exactly is the format for the data to be written here? You do not
> document it in the ABI/ file above, and it looks to be non-trivial to
> understand
> from the code :(
>
Updated documentation in v3 patch series.
> > +
> > +#define CREATE_PGGS_DEVICE(dev, N) \
> > +do { \
> > + if (device_create_file(dev, &dev_attr_pggs##N)) \
> > + dev_err(dev, "unable to create pggs%d attribute\n",
> > +N); \
>
> Ick, no, just use an attribute group please. Handles all of this mess for you
> automatically, and will unwind properly if you have an error (which this macro
> does not do.)
>
> thanks,
>
> greg k-h
Fixed in v3 patch series.
Thanks,
Jolly Shah
