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Subject: Re: [PATCH] clk: Fix a missing check on regmap_bulk_read
To:     Aditya Pakki <pakki001@umn.edu>
Cc:     kjlu@umn.edu, Michael Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>, linux-clk@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20181224190032.23167-1-pakki001@umn.edu>
From:   Marek Vasut <marek.vasut@gmail.com>
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Message-ID: <dc74d564-8db7-a270-5bc3-44993a966f82@gmail.com>
Date:   Wed, 9 Jan 2019 22:22:06 +0100
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On 12/24/18 8:00 PM, Aditya Pakki wrote:
> Currently, vc5_pll_recalc_rate() may produce incorrect output when
> regmap_bulk_read() fails. The fix checks the return value of the
> latter function and returns 0 in case of failure.
> 
> Signed-off-by: Aditya Pakki <pakki001@umn.edu>
> ---
>  drivers/clk/clk-versaclock5.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/clk/clk-versaclock5.c b/drivers/clk/clk-versaclock5.c
> index decffb3826ec..cd76a893c594 100644
> --- a/drivers/clk/clk-versaclock5.c
> +++ b/drivers/clk/clk-versaclock5.c
> @@ -413,7 +413,8 @@ static unsigned long vc5_pll_recalc_rate(struct clk_hw *hw,
>  	u32 div_int, div_frc;
>  	u8 fb[5];
>  
> -	regmap_bulk_read(vc5->regmap, VC5_FEEDBACK_INT_DIV, fb, 5);
> +	if (regmap_bulk_read(vc5->regmap, VC5_FEEDBACK_INT_DIV, fb, 5))
> +		return 0;

Shouldn't this return ret on failure ?

>  	div_int = (fb[0] << 4) | (fb[1] >> 4);
>  	div_frc = (fb[2] << 16) | (fb[3] << 8) | fb[4];
> 


-- 
Best regards,
Marek Vasut