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Date:   Tue, 28 Apr 2020 15:41:29 +0300
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Linus Walleij <linus.walleij@linaro.org>
Cc:     Bartosz Golaszewski <bgolaszewski@baylibre.com>,
        linux-gpio <linux-gpio@vger.kernel.org>,
        Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= 
        <u.kleine-koenig@pengutronix.de>,
        Paul Thomas <pthomas8589@gmail.com>
Subject: Re: [PATCH v3 1/3] gpio: pca953x: Rewrite ->get_multiple() function
Message-ID: <20200428124129.GR185537@smile.fi.intel.com>
References: <20200420172752.33588-1-andriy.shevchenko@linux.intel.com>
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On Tue, Apr 28, 2020 at 02:13:21PM +0200, Linus Walleij wrote:
> On Tue, Apr 21, 2020 at 5:42 PM Bartosz Golaszewski
> <bgolaszewski@baylibre.com> wrote:
> > wt., 21 kwi 2020 o 15:03 Andy Shevchenko
> > <andriy.shevchenko@linux.intel.com> napisał(a):
> > > On Mon, Apr 20, 2020 at 08:27:50PM +0300, Andy Shevchenko wrote:

...

> I don't mind trying to put in code to optimize use cases
> when accessing single bytes here either. But I'd like there
> to be explicit comments in the code saying why these
> optimizations are there. Can we do those on top of
> this (hopefully) known working base?

As I pointed out to Paul, the optimization like he proposed is not bad thing
per se, the implementation is. On top of that I suggested to take a look to IRQ
status bits, which presumable will leverage from this optimization as well.

So, After applying this series it would be matter of change one line in the
->get_multiple() to replace read_regs() with optimized version or so along with
IRQ bits changes.

-- 
With Best Regards,
Andy Shevchenko