Re: [greybus-dev] [PATCH 1/8] driver core: Add helper for accessing Power Management callbacs

From: "Krzysztof Wilczyński" <kw@linux.com>
To: Alex Elder <elder@linaro.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Ulf Hansson <ulf.hansson@linaro.org>,
	linux-pci@vger.kernel.org,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	Pavel Machek <pavel@ucw.cz>,
	linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org,
	Kevin Hilman <khilman@kernel.org>,
	Julian Wiedmann <jwi@linux.ibm.com>,
	linux-acpi@vger.kernel.org, Jakub Kicinski <kuba@kernel.org>,
	Dan Carpenter <dan.carpenter@oracle.com>,
	Len Brown <lenb@kernel.org>,
	linux-pm@vger.kernel.org,
	"James E.J. Bottomley" <jejb@linux.ibm.com>,
	Ursula Braun <ubraun@linux.ibm.com>,
	Johan Hovold <johan@kernel.org>,
	greybus-dev@lists.linaro.org,
	John Stultz <john.stultz@linaro.org>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Felipe Balbi <balbi@kernel.org>, Alex Elder <elder@kernel.org>,
	"Martin K. Petersen" <martin.petersen@oracle.com>,
	netdev@vger.kernel.org, linux-usb@vger.kernel.org,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Karsten Graul <kgraul@linux.ibm.com>,
	"David S. Miller" <davem@davemloft.net>
Subject: Re: [greybus-dev] [PATCH 1/8] driver core: Add helper for accessing Power Management callbacs
Date: Tue, 26 May 2020 17:01:14 +0200	[thread overview]
Message-ID: <20200526150114.GB75990@rocinante> (raw)
In-Reply-To: <41c42552-0f4f-df6a-d587-5c62333aa6a8@linaro.org>

Hello Alex and Greg,

[...]
> This could just be:
> 
> 	if (drv)
> 		return drv->pm;
> 
> 	return NULL;
> 
> Or if you want to evoke passion in Greg:
> 
> 	return drv ? drv->pm : NULL;
> 
> 					-Alex
> 
> > I hate ? : lines with a passion, as they break normal pattern mattching
> > in my brain.  Please just spell this all out:
> > 	if (drv && drv->pm)
> > 		return drv->pm;
> > 	return NULL;
> > 
> > Much easier to read, and the compiler will do the exact same thing.
> > 
> > Only place ? : are ok to use in my opinion, are as function arguments.

I will steer away from the ternary operator next time.  Also, good to
learn about Greg's preference.

Thank you both!

Krzysztof