Thanks for review Greg, > -----Original Message----- > From: Greg KH [mailto:gre...@linuxfoundation.org] > Sent: Tuesday, January 23, 2018 12:41 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 4/4] drivers: firmware: xilinx: Add debugfs interface > > On Wed, Jan 17, 2018 at 12:20:34PM -0800, Jolly Shah wrote: > > +/* Setup debugfs fops */ > > +static const struct file_operations fops_zynqmp_pm_dbgfs = { > > + .owner = THIS_MODULE, > > + .write = zynqmp_pm_debugfs_api_write, > > + .read = zynqmp_pm_debugfs_api_version_read, > > +}; > > + > > +/** > > + * zynqmp_pm_api_debugfs_init - Initialize debugfs interface > > + * > > + * Return: Returns 0 on success > > + * Corresponding error code otherwise > > + */ > > +int zynqmp_pm_api_debugfs_init(void) > > +{ > > + int err; > > + > > + /* Initialize debugfs interface */ > > + zynqmp_pm_debugfs_dir = debugfs_create_dir(DRIVER_NAME, NULL); > > + if (!zynqmp_pm_debugfs_dir) { > > + pr_err("debugfs_create_dir failed\n"); > > + return -ENODEV; > > + } > > No, you should NEVER care if a debugfs call returned an error or not, no need > to > check it at all. Your code path should not change based on the return value > as > no code should depened on the functionality of debugfs. > > Any error returned by a debugfs call can be passed right back into it with no > problems, so again, no need to check this. >
Fixed in v3 patch series. Not saving dentries anymore but added check to show warning message instead of error. > > + > > + zynqmp_pm_debugfs_power = > > + debugfs_create_file("pm", 0220, > > + zynqmp_pm_debugfs_dir, NULL, > > + &fops_zynqmp_pm_dbgfs); > > + if (!zynqmp_pm_debugfs_power) { > > + pr_err("debugfs_create_file power failed\n"); > > + err = -ENODEV; > > + goto err_dbgfs; > > + } > > + > > + zynqmp_pm_debugfs_api_version = > > + debugfs_create_file("api_version", 0444, > > + zynqmp_pm_debugfs_dir, NULL, > > + &fops_zynqmp_pm_dbgfs); > > + if (!zynqmp_pm_debugfs_api_version) { > > + pr_err("debugfs_create_file api_version failed\n"); > > + err = -ENODEV; > > + goto err_dbgfs; > > + } > > Why do you save these dentries at all anyway? You never do anything with > them, just create the files and away you go, no need to worry about anything. > > Remember, debugfs was created to be very simple to use, don't make it more > complex than it has to be please. > > thanks, > > greg k-h Fixed in v3 patch series. Thanks, Jolly Shah