linux-kernel - Re: [PATCH net-next 2/2] nfc: s3fwrn5: use devm_clk_get_optional

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 for Android: free password hash cracker in your pocket

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

Date:   Thu, 29 Sep 2022 07:58:24 -0700
From:   Dmitry Torokhov <dmitry.torokhov@...il.com>
To:     Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>,
        Krzysztof Opasiak <k.opasiak@...sung.com>
Cc:     netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH net-next 2/2] nfc: s3fwrn5: use
 devm_clk_get_optional_enabled() helper

On Wed, Sep 28, 2022 at 10:04:26PM -0700, Dmitry Torokhov wrote:
> Because we enable the clock immediately after acquiring it in probe,
> we can combine the 2 operations and use devm_clk_get_optional_enabled()
> helper.
> 
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@...il.com>
> ---
>  drivers/nfc/s3fwrn5/i2c.c | 14 ++++----------
>  1 file changed, 4 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/nfc/s3fwrn5/i2c.c b/drivers/nfc/s3fwrn5/i2c.c
> index fb36860df81c..2aaee2a8ff1c 100644
> --- a/drivers/nfc/s3fwrn5/i2c.c
> +++ b/drivers/nfc/s3fwrn5/i2c.c
> @@ -209,22 +209,16 @@ static int s3fwrn5_i2c_probe(struct i2c_client *client,
>  	if (ret < 0)
>  		return ret;
>  
> -	phy->clk = devm_clk_get_optional(&client->dev, NULL);
> -	if (IS_ERR(phy->clk))
> -		return dev_err_probe(&client->dev, PTR_ERR(phy->clk),
> -				     "failed to get clock\n");
> -
>  	/*
>  	 * S3FWRN5 depends on a clock input ("XI" pin) to function properly.
>  	 * Depending on the hardware configuration this could be an always-on
>  	 * oscillator or some external clock that must be explicitly enabled.
>  	 * Make sure the clock is running before starting S3FWRN5.
>  	 */
> -	ret = clk_prepare_enable(phy->clk);
> -	if (ret < 0) {
> -		dev_err(&client->dev, "failed to enable clock: %d\n", ret);
> -		return ret;
> -	}
> +	phy->clk = devm_clk_get_optional_enabled(&client->dev, NULL);
> +	if (IS_ERR(phy->clk))
> +		return dev_err_probe(&client->dev, PTR_ERR(phy->clk),
> +				     "failed to get clock\n");

I forgot to remove clk_disable_unprepare() in remove method, I will
resubmit.

Thanks.

-- 
Dmitry