linux-kernel - Re: [PATCH 2/2] i2c: jz4780: Use devm_clk_get

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1473866ced990d435f31e541e03d1676aa04b4ae.camel@crapouillou.net>
Date: Thu, 22 Aug 2024 11:35:36 +0200
From: Paul Cercueil <paul@...pouillou.net>
To: Rong Qianfeng <rongqianfeng@...o.com>, Wolfram Sang
	 <wsa+renesas@...g-engineering.com>, Andi Shyti <andi.shyti@...nel.org>, 
	linux-renesas-soc@...r.kernel.org, linux-i2c@...r.kernel.org, 
	linux-kernel@...r.kernel.org, linux-mips@...r.kernel.org
Cc: opensource.kernel@...o.com
Subject: Re: [PATCH 2/2] i2c: jz4780: Use devm_clk_get_enabled() helpers

Hi Rong,

Le jeudi 22 août 2024 à 10:52 +0800, Rong Qianfeng a écrit :
> The devm_clk_get_enabled() helpers:
>     - call devm_clk_get()
>     - call clk_prepare_enable() and register what is needed in order
> to
>      call clk_disable_unprepare() when needed, as a managed resource.
> 
> This simplifies the code and avoids the calls to
> clk_disable_unprepare().
> 
> While at it, remove the goto label "err:", and use its return value
> to 
> return the error code.
> 
> Signed-off-by: Rong Qianfeng <rongqianfeng@...o.com>

Acked-by: Paul Cercueil <paul@...pouillou.net>

With a small suggestion below.

> ---
>  drivers/i2c/busses/i2c-jz4780.c | 21 ++++++---------------
>  1 file changed, 6 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-jz4780.c
> b/drivers/i2c/busses/i2c-jz4780.c
> index 4aafdfab6305..f5362c5dfb50 100644
> --- a/drivers/i2c/busses/i2c-jz4780.c
> +++ b/drivers/i2c/busses/i2c-jz4780.c
> @@ -792,26 +792,22 @@ static int jz4780_i2c_probe(struct
> platform_device *pdev)
>  
>  	platform_set_drvdata(pdev, i2c);
>  
> -	i2c->clk = devm_clk_get(&pdev->dev, NULL);
> +	i2c->clk = devm_clk_get_enabled(&pdev->dev, NULL);
>  	if (IS_ERR(i2c->clk))
>  		return PTR_ERR(i2c->clk);
>  
> -	ret = clk_prepare_enable(i2c->clk);
> -	if (ret)
> -		return ret;
> -
>  	ret = of_property_read_u32(pdev->dev.of_node, "clock-
> frequency",
>  				   &clk_freq);
>  	if (ret) {
>  		dev_err(&pdev->dev, "clock-frequency not specified
> in DT\n");
> -		goto err;
> +		return ret;
>  	}

Since there is no more special handling needed here, you could just:
if (ret)
    return dev_err_probe(&pdev->dev, ret, "clock-frequency...\n");

And the same for the other error handling paths that you changed.

I wouldn't request a V2 just for that though.

Cheers,
-Paul

>  
>  	i2c->speed = clk_freq / 1000;
>  	if (i2c->speed == 0) {
>  		ret = -EINVAL;
>  		dev_err(&pdev->dev, "clock-frequency minimum is
> 1000\n");
> -		goto err;
> +		return ret;
>  	}
>  	jz4780_i2c_set_speed(i2c);
>  
> @@ -827,29 +823,24 @@ static int jz4780_i2c_probe(struct
> platform_device *pdev)
>  
>  	ret = platform_get_irq(pdev, 0);
>  	if (ret < 0)
> -		goto err;
> +		return ret;
>  	i2c->irq = ret;
>  	ret = devm_request_irq(&pdev->dev, i2c->irq, jz4780_i2c_irq,
> 0,
>  			       dev_name(&pdev->dev), i2c);
>  	if (ret)
> -		goto err;
> +		return ret;
>  
>  	ret = i2c_add_adapter(&i2c->adap);
>  	if (ret < 0)
> -		goto err;
> +		return ret;
>  
>  	return 0;
> -
> -err:
> -	clk_disable_unprepare(i2c->clk);
> -	return ret;
>  }
>  
>  static void jz4780_i2c_remove(struct platform_device *pdev)
>  {
>  	struct jz4780_i2c *i2c = platform_get_drvdata(pdev);
>  
> -	clk_disable_unprepare(i2c->clk);
>  	i2c_del_adapter(&i2c->adap);
>  }
>