From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerry Hoemann Subject: Re: [RFC PATCH v2 08/10] rtc: bd70528: Initial support for ROHM bd70528 RTC Date: Tue, 29 Jan 2019 17:24:04 -0700 Message-ID: <20190130002404.GA19729@anatevka> References: <20190125110536.GA29321@localhost.localdomain> <35bbc5b9-5f8c-ec80-3eaa-bb2c0e2812c9@roeck-us.net> <20190128202656.GA17466@anatevka> <20190129070103.GA2551@localhost.localdomain> Reply-To: Jerry.Hoemann@hpe.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20190129070103.GA2551@localhost.localdomain> Sender: linux-kernel-owner@vger.kernel.org To: Matti Vaittinen Cc: Guenter Roeck , mazziesaccount@gmail.com, heikki.haikola@fi.rohmeurope.com, mikko.mutanen@fi.rohmeurope.com, lee.jones@linaro.org, robh+dt@kernel.org, mark.rutland@arm.com, broonie@kernel.org, gregkh@linuxfoundation.org, rafael@kernel.org, mturquette@baylibre.com, sboyd@kernel.org, linus.walleij@linaro.org, bgolaszewski@baylibre.com, sre@kernel.org, lgirdwood@gmail.com, a.zummo@towertech.it, alexandre.belloni@bootlin.com, wim@linux-watchdog.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, linux-gpio@vger.kernel.org, linux-pm@vger.kernel.org, linux-rtc@vger.kernel.org, linux-watchdog@vger.kernel.org List-Id: devicetree@vger.kernel.org On Tue, Jan 29, 2019 at 09:01:03AM +0200, Matti Vaittinen wrote: > On Mon, Jan 28, 2019 at 01:26:56PM -0700, Jerry Hoemann wrote: > > On Sat, Jan 26, 2019 at 08:30:24AM -0800, Guenter Roeck wrote: > > > On 1/25/19 3:05 AM, Matti Vaittinen wrote: > > > > +static int bd70528_set_wake(struct bd70528 *bd70528, > > > > + int enable, int *old_state) > > > > +{ > > > > + int ret; > > > > + unsigned int ctrl_reg; > > > > + > > > > + ret = regmap_read(bd70528->chip.regmap, BD70528_REG_WAKE_EN, &ctrl_reg); > > > > + if (ret) > > > > + return ret; > > > > + > > > > + if (old_state) { > > > > + if (ctrl_reg & BD70528_MASK_WAKE_EN) > > > > + *old_state |= BD70528_WAKE_STATE_BIT; > > > > + else > > > > + *old_state &= ~BD70528_WAKE_STATE_BIT; > > > > + > > > > + if ((!enable) == (!(*old_state & BD70528_WAKE_STATE_BIT))) > > > > + return 0; > > > > > > I think > > > if (enable == !!(*old_state & BD70528_WAKE_STATE_BIT)) > > > would be much better readable. Even if not, there are way too many () > > > in the above conditional. > > > > > > > The substitution is not equivalent to original. I think you mean: > > > > if (!!enable == !!(*old_state & BD70528_WAKE_STATE_BIT)) > > Thanks Jerry! Good catch! I originally wanted that all non-zero values > of 'enable' would be 'true'. So maybe I just use the original approach > but get rid of extra parenthesis which were pointed out by Guenter. > > if (!enable == !(*old_state & BD70528_WAKE_STATE_BIT)) > should do it just fine, right? > The use of "!!" to turn an int into one of two Boolean values (0 | 1) is used extensively in Linux and as such might make the intent of the code a bit clearer which I take as checking to see the states match. But, I will defer to you and Guenter on the question. -- ----------------------------------------------------------------------------- Jerry Hoemann Software Engineer Hewlett Packard Enterprise -----------------------------------------------------------------------------