From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Keeping <john@metanate.com>
Subject: Re: [PATCH 1/4] iio: adc: rockchip_saradc: reset saradc controller
 before programming it
Date: Tue, 26 Jul 2016 10:00:07 +0100
Message-ID: <20160726100007.5166e7f9.john@metanate.com>
References: <1469513510-1516-1-git-send-email-wxt@rock-chips.com>
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To: Caesar Wang <wxt@rock-chips.com>
Cc: jic23@kernel.org, devicetree@vger.kernel.org, heiko@sntech.de, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, dianders@chromium.org, linux-rockchip@lists.infradead.org, robh+dt@kernel.org, linux@roeck-us.net
List-Id: devicetree@vger.kernel.org

On Tue, 26 Jul 2016 14:11:47 +0800, Caesar Wang wrote:

> SARADC controller needs to be reset before programming it, otherwise
> it will not function properly.
> 
> Signed-off-by: Caesar Wang <wxt@rock-chips.com>
> Cc: Jonathan Cameron <jic23@kernel.org>
> Cc: Heiko Stuebner <heiko@sntech.de>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: linux-iio@vger.kernel.org
> Cc: linux-rockchip@lists.infradead.org
> ---
> 
> diff --git a/drivers/iio/adc/rockchip_saradc.c b/drivers/iio/adc/rockchip_saradc.c
> index f9ad6c2..2f0e110 100644
> --- a/drivers/iio/adc/rockchip_saradc.c
> +++ b/drivers/iio/adc/rockchip_saradc.c
> @@ -218,6 +231,13 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
>  	if (IS_ERR(info->regs))
>  		return PTR_ERR(info->regs);
>  
> +	info->reset = devm_reset_control_get(&pdev->dev, "saradc-apb");
> +	if (IS_ERR(info->reset)) {
> +		ret = PTR_ERR(info->reset);
> +		dev_err(&pdev->dev, "failed to get saradc reset: %d\n", ret);
> +		return ret;
> +	}

Does this need to handle ENOENT so as to avoid failing with old device
tree blobs?