linux-kernel - Re: [PATCH v4 1/5] gpio-f7188x: Add GPIO support for Nuvoton NCT6116

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]

Message-ID: <20220824161757.4ca3bb97@md1za8fc.ad001.siemens.net>
Date:   Wed, 24 Aug 2022 16:17:57 +0200
From:   Henning Schild <henning.schild@...mens.com>
To:     Hans de Goede <hdegoede@...hat.com>
Cc:     simon.guinot@...uanux.org,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Linus Walleij <linus.walleij@...aro.org>,
        Bartosz Golaszewski <brgl@...ev.pl>,
        Pavel Machek <pavel@....cz>, Mark Gross <markgross@...nel.org>,
        Lee Jones <lee@...nel.org>, linux-gpio@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-leds@...r.kernel.org,
        platform-driver-x86@...r.kernel.org,
        Sheng-Yuan Huang <syhuang3@...oton.com>,
        Tasanakorn Phaipool <tasanakorn@...il.com>
Subject: Re: [PATCH v4 1/5] gpio-f7188x: Add GPIO support for Nuvoton
 NCT6116

Am Wed, 24 Aug 2022 15:54:28 +0200
schrieb Hans de Goede <hdegoede@...hat.com>:

> Hi Henning,
> 
> On 8/24/22 15:50, Henning Schild wrote:
> > Am Wed, 24 Aug 2022 15:10:55 +0200
> > schrieb simon.guinot@...uanux.org:
> >   
> >> On Tue, Aug 23, 2022 at 04:54:59PM +0200, Henning Schild wrote:  
> >>> Am Tue, 23 Aug 2022 17:47:38 +0300
> >>> schrieb Andy Shevchenko <andriy.shevchenko@...ux.intel.com>:    
> >>
> >> Hi Andy,
> >>
> >> Thanks for this new version. It is looking good to me.
> >>  
> >>>     
> >>>> On Tue, Aug 23, 2022 at 12:23:40PM +0200, Henning Schild wrote:
> >>>>   
> >>>>> Add GPIO support for Nuvoton NCT6116 chip. Nuvoton SuperIO
> >>>>> chips are very similar to the ones from Fintek. In other
> >>>>> subsystems they also share drivers and are called a family of
> >>>>> drivers.
> >>>>>
> >>>>> For the GPIO subsystem the only difference is that the direction
> >>>>> bit is reversed and that there is only one data bit per pin. On
> >>>>> the SuperIO level the logical device is another one.
> >>>>>
> >>>>> On a chip level we do not have a manufacturer ID to check and
> >>>>> also no revision.      
> >>>>
> >>>> ...
> >>>>     
> >>>>> - * GPIO driver for Fintek Super-I/O F71869, F71869A, F71882,
> >>>>> F71889 and F81866
> >>>>> + * GPIO driver for Fintek and Nuvoton Super-I/O chips      
> >>>>
> >>>> I'm not sure it's good idea to drop it from here. It means reader
> >>>> has to get this info in a hard way.
> >>>>
> >>>> ...    
> >>>
> >>> Let us see what others say. I wanted to keep this in line with
> >>> what Kconfig says and the oneliner in the Kconfig was getting
> >>> pretty longish. Hence i decided to shorten that. Other drivers
> >>> also seem to not list all the possible chips in many places, it
> >>> is all maint effort when a new chips is added and the list is in
> >>> like 5 places.    
> >>
> >> I agree with you that we can drop this line. It was already
> >> incomplete and the information is quite readable a few lines below
> >> in both the define list and the chip enumeration.
> >>  
> >>>     
> >>>>> +#define gpio_dir_invert(type)	((type) == nct6116d)
> >>>>> +#define gpio_data_single(type)	((type) == nct6116d)
> >>>>>  
> >>>>
> >>>> What's prevents us to add a proper prefix to these? I don't like
> >>>> the idea of them having "gpio" prefix.
> >>>>
> >>>> ...
> >>>>     
> >>>>> +		pr_info(DRVNAME ": Unsupported device
> >>>>> 0x%04x\n", devid);
> >>>>> +			pr_debug(DRVNAME ": Not a Fintek
> >>>>> device at 0x%08x\n", addr);
> >>>>> +	pr_info(DRVNAME ": Found %s at %#x\n",
> >>>>> +		pr_info(DRVNAME ":   revision %d\n",      
> >>>>
> >>>> Can we, please, utilize pr_fmt()?
> >>>>     
> >>>>> +			(int)superio_inb(addr,
> >>>>> SIO_FINTEK_DEVREV));      
> >>>>
> >>>> Explicit casting in printf() means wrong specifier in 99% of
> >>>> cases.   
> >>>
> >>> For all the other comments i will wait for a second opinion. I
> >>> specifically did not change existing code for more than the
> >>> functional changes needed. And a bit of checkpatch.pl fixing.
> >>> Beautification could be done on the way but would only cause
> >>> inconsistency. That driver is what it is, if someone wants to
> >>> overhaul the style ... that should be another patch. One likely
> >>> not coming from me.    
> >>
> >> About the int cast, I think you can drop it while you are updating
> >> this line. It is unneeded.  
> > 
> > Ok two voices for doing that one fix along the way. I will send a v5
> > and hope nobody insists on me fixing the other findings in code i
> > never wrote.  
> 
> You did not write it, but you are using it to do hw-enablement for
> your company's products. So being asked to also some touch-ups
> left and right while you are at it really is not unexpected IMHO.

Sure thing. Dropping a few characters from a line i touch anyhow is
easy enough. But i.e a refactoring to pr_fmt would feel like asking too
much in my book. That feels like work of the author or maintainer.

In fact i am just doing the homework of what i think should have long
been done by Nuvoton.

I hope that v5 will be acceptable.

Henning 

> Regards,
> 
> Hans
>