From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-path: Subject: Re: [1/2] pmbus: added tps544c20 driver with trimming support To: Guenter Roeck Cc: linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org References: <20171020103916.3309-2-romain.porte@nokia.com> <20171021162048.GA13173@roeck-us.net> From: Romain Porte Message-ID: <47c2dd13-c357-56fa-6886-08ce6e2b9d92@nokia.com> Date: Mon, 23 Oct 2017 15:34:24 +0200 MIME-Version: 1.0 In-Reply-To: <20171021162048.GA13173@roeck-us.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US List-ID: On 21/10/2017 18:20, Guenter Roeck wrote: > This should be part of device programming in manufacturing, just like, > say, current calibration. It should not be user programmable, even less so > runtime programmable. On top of that, we definitely don't want to make > STORE_USER_ALL available to user space. Both can too easily result in > a bricked device (bad enough that the register values are writable using > i2cset). After some work, I have tested accessing these registers using i2cget and i2cset and I can reproduce all the features I have implemented in this driver. I think am going to re-implement my calibration procedure using i2cget and i2cset in userspace. I thought it could be a good idea to make this accessible by sysfs entries. Since one must read the datasheet for calibrating the component, I guess it is not a big deal to have users to find register addresses/sizes and write to them using userspace commands instead of (over?)simplifying it by providing dedicated sysfs entries. Romain.