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Subject: Re: [PATCH v4 1/2] gpio: add GPO driver for PCA9570
To:     Andy Shevchenko <andy.shevchenko@gmail.com>
Cc:     Linus Walleij <linus.walleij@linaro.org>,
        Bartosz Golaszewski <bgolaszewski@baylibre.com>,
        Michael Walle <michael@walle.cc>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>
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From:   Sungbo Eo <mans0n@gorani.run>
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Date:   Fri, 3 Jul 2020 09:12:58 +0900
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On 2020-07-02 21:36, Andy Shevchenko wrote:
>> +       gpio->chip.ngpio = i2c_match_id(pca9570_id_table, client)->driver_data;
> 
> Oh, avoid direct access to the table like this. And you may simply use
> device_get_match_data().

I'm not sure if it really does the same thing, but I'll try following 
your suggestion.

> ...
> 
>> +       /* Read the current output level */
>> +       (void) pca9570_read(gpio, &gpio->out);
> 
> (void) casting is not needed. And I'm not sure hiding an error is a
> good idea. But the latter is up to you.
> 

If it returns an error then it might be because the chip could not be 
detected on the bus at that time. But I think aborting probe for that is 
too much.
(void) casting was to indicate that I want to ignore the error, but I'll 
remove it as you said.

Thanks.