Reply-To: <michael.hennerich@analog.com>
Subject: Re: [PATCH] staging: iio: ad7192: Use the dedicated reset function
To: Stefan Popa <stefan.popa@analog.com>,
        Lars-Peter Clausen <lars@metafoo.de>,
        Jonathan Cameron <jic23@kernel.org>
CC: Hartmut Knaack <knaack.h@gmx.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        <linux-iio@vger.kernel.org>, <devel@driverdev.osuosl.org>,
        <linux-kernel@vger.kernel.org>
References: <1505397028-15461-1-git-send-email-stefan.popa@analog.com>
From: Michael Hennerich <michael.hennerich@analog.com>
Organization: Analog Devices Inc.
Message-ID: <1c2f62f5-3a64-29a0-7bbf-8545173530f9@analog.com>
Date: Thu, 14 Sep 2017 16:31:06 +0200
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On 14.09.2017 15:50, Stefan Popa wrote:
> SPI host drivers can use DMA to transfer data, so the buffer should be properly allocated.
> Keeping it on the stack could cause an undefined behavior.
> 
> The dedicated reset function solves this issue.
> 
> Signed-off-by: Stefan Popa <stefan.popa@analog.com>

Acked-by: Michael Hennerich <michael.hennerich@analog.com>

Well done!


> ---
>   drivers/staging/iio/adc/ad7192.c | 4 +---
>   1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/staging/iio/adc/ad7192.c b/drivers/staging/iio/adc/ad7192.c
> index d11c6de..6150d27 100644
> --- a/drivers/staging/iio/adc/ad7192.c
> +++ b/drivers/staging/iio/adc/ad7192.c
> @@ -223,11 +223,9 @@ static int ad7192_setup(struct ad7192_state *st,
>   	struct iio_dev *indio_dev = spi_get_drvdata(st->sd.spi);
>   	unsigned long long scale_uv;
>   	int i, ret, id;
> -	u8 ones[6];
>   
>   	/* reset the serial interface */
> -	memset(&ones, 0xFF, 6);
> -	ret = spi_write(st->sd.spi, &ones, 6);
> +	ret = ad_sd_reset(&st->sd, 48);
>   	if (ret < 0)
>   		goto out;
>   	usleep_range(500, 1000); /* Wait for at least 500us */
> 


-- 
Greetings,
Michael

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