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Message-ID: <c23cdde58b9f724f51787c6c38478df983be6efa.camel@microchip.com>
Subject: Re: [PATCH v3 5/6] spi: at91-usart: add driver for at91-usart as spi
From:   Radu Pirea <radu.pirea@microchip.com>
To:     Andy Shevchenko <andy.shevchenko@gmail.com>,
        devicetree <devicetree@vger.kernel.org>,
        "open list:SERIAL DRIVERS" <linux-serial@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-arm Mailing List <linux-arm-kernel@lists.infradead.org>,
        linux-spi <linux-spi@vger.kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        "Rob Herring" <robh+dt@kernel.org>,
        Lee Jones <lee.jones@linaro.org>,
        "Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
        Jiri Slaby <jslaby@suse.com>,
        Richard Genoud <richard.genoud@gmail.com>,
        <alexandre.belloni@bootlin.com>,
        Nicolas Ferre <nicolas.ferre@microchip.com>,
        Mark Brown <broonie@kernel.org>
Date:   Tue, 15 May 2018 12:22:24 +0300
In-Reply-To: <CAHp75VdRrL25Jgnbk64Qqc5RY3uJdcntJ3xwRdp3F+rRFeTHBA@mail.gmail.com>
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         <CAHp75Ve3Ugnjjm8EZkPQTZSvH1qad1e5SqjOn8zz5syHSQea_g@mail.gmail.com>
         <5a3930b867cf8c279953d08c5d5dd1d93113a43b.camel@microchip.com>
         <CAHp75VdRrL25Jgnbk64Qqc5RY3uJdcntJ3xwRdp3F+rRFeTHBA@mail.gmail.com>
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On Mon, 2018-05-14 at 20:38 +0300, Andy Shevchenko wrote:
> First of all, do not remove mailing lists from Cc and people if you
> are not sure they do not need your stuff.
> 
Sorry. My mistake. 
> On Mon, May 14, 2018 at 11:11 AM, Radu Pirea
> <radu.pirea@microchip.com> wrote:
> > On Sun, 2018-05-13 at 16:33 +0300, Andy Shevchenko wrote:
> > > On Fri, May 11, 2018 at 1:38 PM, Radu Pirea <radu.pirea@microchip
> > > .com
> > > > wrote:
> > > > +static void at91_usart_spi_cleanup(struct spi_device *spi)
> > > > +{
> > > > +       struct at91_usart_spi_device *ausd = spi-
> > > > >controller_state;
> > > > +
> > > > +       if (!ausd)
> > > > +               return;
> > > 
> > > Is it even possible?
> > 
> > Theoretically yes.
> 
> I would like to know real circumstances when it might happen.
That check was used in debug stage of driver. I will remove.
> 
> > > 
> > > Anyway the code below will work fine even if it's the case.
> > > 
> > > > +
> > > > +       spi->controller_state = NULL;
> > > > +       kfree(ausd);
> > > > +}
> > > The question is, why you didn't utilize what SPI core provides
> > > you?
> > 
> > I tried, but it did not work the way I expected.
> 
> So, what is not going as expected in "SPI core takes care of CSs"
> case?
> Did you use oscilloscope for that?
Yes, I used and CSs was not asserted. Anyway, I will will try again.
>