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Subject: Re: [PATCH v2] net: dsa: b53: Using sleep-able operations in
 b53_switch_reset_gpio
To:     Jia-Ju Bai <baijiaju1990@gmail.com>, andrew@lunn.ch,
        vivien.didelot@savoirfairelinux.com, preid@electromag.com.au
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org
References: <1523497702-7200-1-git-send-email-baijiaju1990@gmail.com>
From:   Florian Fainelli <f.fainelli@gmail.com>
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Date:   Thu, 12 Apr 2018 09:32:59 -0700
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On 04/11/2018 06:48 PM, Jia-Ju Bai wrote:
> b53_switch_reset_gpio() is never called in atomic context.
> 
> The call chain ending up at b53_switch_reset_gpio() is:
> [1] b53_switch_reset_gpio() <- b53_switch_reset() <-
>     b53_reset_switch() <- b53_setup()
> 
> b53_switch_reset_gpio() is set as ".setup" in struct dsa_switch_ops.
> This function is not called in atomic context.
> 
> Despite never getting called from atomic context, b53_switch_reset_gpio()
> calls non-sleep operations mdelay() and gpio_set_value().
> They are not necessary and can be replaced with msleep() 
> and gpio_set_value_cansleep().
> 
> This is found by a static analysis tool named DCNS written by myself.
> And I also manually check it.
> 
> Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>

Acked-by: Florian Fainelli <f.fainelli@gmail.com>

-- 
Florian