Thanks for review Greg,
> -----Original Message-----
> From: Greg KH [mailto:[email protected]]
> Sent: Tuesday, January 23, 2018 12:41 AM
> To: Jolly Shah <[email protected]>
> Cc: [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; linux-
> [email protected]; [email protected]; Rajan Vaja
> <[email protected]>; Jolly Shah <[email protected]>
> 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
