linux-kernel - Re: [PATCH v3 18/19] hwmon: (mr75203) add debugfs to read and write temperature coefficients

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 31 Aug 2022 15:14:35 +0300
From:   Andy Shevchenko <andriy.shevchenko@...el.com>
To:     Eliav Farber <farbere@...zon.com>
Cc:     jdelvare@...e.com, linux@...ck-us.net, robh+dt@...nel.org,
        p.zabel@...gutronix.de, rtanwar@...linear.com,
        linux-hwmon@...r.kernel.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, talel@...zon.com, hhhawa@...zon.com,
        jonnyc@...zon.com, hanochu@...zon.com, ronenk@...zon.com,
        itamark@...zon.com, shellykz@...zon.com, shorer@...zon.com,
        amitlavi@...zon.com, almogbs@...zon.com, dkl@...zon.com,
        rahul.tanwar@...ux.intel.com
Subject: Re: [PATCH v3 18/19] hwmon: (mr75203) add debugfs to read and write
 temperature coefficients

On Tue, Aug 30, 2022 at 07:22:11PM +0000, Eliav Farber wrote:
> This change adds debugfs to read and write temperature sensor coefficients
> - g, h, j and cal5.
> 
> The coefficients can vary between product and product, so it can be very
> useful to be able to modify them on the fly during the calibration
> process.
> 
> e.g.:
> 
> cat /sys/kernel/debug/940f23d0000.pvt/ts_coeff_cal5
> 4096
> 
> echo 83000 > sys/kernel/debug/940f23d0000.pvt/ts_coeff_g

...

> +	pvt->dbgfs_dir = debugfs_create_dir(dev_name(dev), NULL);

> +	if (!pvt->dbgfs_dir) {
> +		dev_err(dev, "Failed to create dbgfs_dir\n");
> +		return -EINVAL;
> +	}

No, just don't check the return value of debugfs API calls.

> +	debugfs_create_file("ts_coeff_h", 0644, pvt->dbgfs_dir, pvt,
> +			    &pvt_ts_coeff_h_fops);
> +	debugfs_create_file("ts_coeff_g", 0644, pvt->dbgfs_dir, pvt,
> +			    &pvt_ts_coeff_g_fops);
> +	debugfs_create_file("ts_coeff_j", 0644, pvt->dbgfs_dir, pvt,
> +			    &pvt_ts_coeff_j_fops);
> +	debugfs_create_file("ts_coeff_cal5", 0644, pvt->dbgfs_dir,  pvt,
> +			    &pvt_ts_coeff_cal5_fops);

debugfs has helpers for POD types, use them and shrink your code by ~80%.

...

> +	ret = devm_add_action_or_reset(dev, devm_pvt_ts_dbgfs_remove, pvt);
> +	if (ret) {
> +		dev_err(dev, "failed to add action to remove pvt dbgfs (%d)\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	return 0;

return devm_add_...

-- 
With Best Regards,
Andy Shevchenko