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Sender: Guenter Roeck <groeck7@gmail.com>
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Date:   Mon, 5 Sep 2022 08:13:39 -0700
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Subject: Re: [PATCH v1 10/11] watchdog: bd9576_wdt: switch to using
 devm_fwnode_gpiod_get()
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To:     Andy Shevchenko <andy.shevchenko@gmail.com>,
        Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc:     Thierry Reding <thierry.reding@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Matti Vaittinen <mazziesaccount@gmail.com>,
        Lorenzo Pieralisi <lpieralisi@kernel.org>,
        Claudiu Beznea <claudiu.beznea@microchip.com>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Wim Van Sebroeck <wim@linux-watchdog.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        Felipe Balbi <balbi@kernel.org>,
        Alexandre Belloni <alexandre.belloni@bootlin.com>,
        =?UTF-8?Q?Krzysztof_Wilczy=c5=84ski?= <kw@linux.com>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Marc Zyngier <maz@kernel.org>,
        Richard Weinberger <richard@nod.at>,
        David Airlie <airlied@linux.ie>,
        Nicolas Ferre <nicolas.ferre@microchip.com>,
        Alyssa Rosenzweig <alyssa@rosenzweig.io>,
        Bartosz Golaszewski <brgl@bgdev.pl>,
        Jonathan Hunter <jonathanh@nvidia.com>,
        Rob Herring <robh@kernel.org>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        =?UTF-8?Q?Pali_Roh=c3=a1r?= <pali@kernel.org>,
        LINUXWATCHDOG <linux-watchdog@vger.kernel.org>,
        USB <linux-usb@vger.kernel.org>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
        linux-pci <linux-pci@vger.kernel.org>,
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References: <20220903-gpiod_get_from_of_node-remove-v1-0-b29adfb27a6c@gmail.com>
 <20220903-gpiod_get_from_of_node-remove-v1-10-b29adfb27a6c@gmail.com>
 <CAHp75Vd35EOy=mP25=9fmYfqQnbafgotHw1fxk-TdGk6Oc8g8Q@mail.gmail.com>
From:   Guenter Roeck <linux@roeck-us.net>
In-Reply-To: <CAHp75Vd35EOy=mP25=9fmYfqQnbafgotHw1fxk-TdGk6Oc8g8Q@mail.gmail.com>
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On 9/5/22 04:09, Andy Shevchenko wrote:
> On Mon, Sep 5, 2022 at 9:33 AM Dmitry Torokhov
> <dmitry.torokhov@gmail.com> wrote:
>>
>> I would like to stop exporting OF-specific devm_gpiod_get_from_of_node()
>> so that gpiolib can be cleaned a bit, so let's switch to the generic
>> fwnode property API.
>>
>> While at it switch the rest of the calls to read properties in
> 
> it, switch
> 
>> bd9576_wdt_probe() to the generic device property API as well.
> 
> ...
> 
>>          struct device *dev = &pdev->dev;
> 
> struct device *parent = dev->parent;
> 
> can make your code slightly neater.
> 
> ...
> 
>> +       count = device_property_count_u32(dev->parent, "rohm,hw-timeout-ms");
>> +       if (count < 0 && count != -EINVAL)
>> +               return count;
>> +
>> +       if (count > 0) {
> 
>> +               if (count > ARRAY_SIZE(hw_margin))
>> +                       return -EINVAL;
> 
> Why double check? You may move it out of the (count > 0).
> 

Two checks will always be needed, so I don't entirely see
how that would be better.

> ...
> 
>> -       if (ret == 1)
>> -               hw_margin_max = hw_margin[0];
> 
>> +               ret = device_property_read_u32_array(dev->parent,
>> +                                                    "rohm,hw-timeout-ms",
>> +                                                    hw_margin, count);
>> +               if (ret < 0)
>> +                       return ret;
> 
> So, only this needs the count > 0 check since below already has it implicitly.
> 
Sorry, I don't understand this comment.

Guenter

>> -       if (ret == 2) {
>> -               hw_margin_max = hw_margin[1];
>> -               hw_margin_min = hw_margin[0];
>> +               if (count == 1)
>> +                       hw_margin_max = hw_margin[0];
>> +
>> +               if (count == 2) {
>> +                       hw_margin_max = hw_margin[1];
>> +                       hw_margin_min = hw_margin[0];
>> +               }
>>          }
>