linux-kernel - Re: [PATCH v3 4/5] crypto: caam - simplfy clock initialization

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Date:   Mon, 17 Jun 2019 19:48:05 +0000
From:   Leonard Crestez <leonard.crestez@....com>
To:     Andrey Smirnov <andrew.smirnov@...il.com>,
        "linux-crypto@...r.kernel.org" <linux-crypto@...r.kernel.org>,
        Horia Geanta <horia.geanta@....com>
CC:     Chris Spencer <christopher.spencer@....co.uk>,
        Cory Tusar <cory.tusar@....aero>,
        Chris Healy <cphealy@...il.com>,
        Lucas Stach <l.stach@...gutronix.de>,
        Aymen Sghaier <aymen.sghaier@....com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v3 4/5] crypto: caam - simplfy clock initialization

On 6/17/2019 7:04 PM, Andrey Smirnov wrote:
> Simplify clock initialization code by converting it to use clk-bulk,
> devres and soc_device_match() match table. No functional change
> intended.

Subject is misspelled.

> +struct clk_bulk_caam {
> +	const struct clk_bulk_data *clks;
> +	int num_clks;
> +};

clks could be an array[0] at the end to avoid an additional allocation.

> +static void disable_clocks(void *private)
> +{
> +	struct clk_bulk_caam *context = private;
> +
> +	clk_bulk_disable_unprepare(context->num_clks,
> +				   (struct clk_bulk_data *)context->clks);
> +}

Not sure using devm for this is worthwhile. Maybe someday CAAM clks will 
be enabled dynamically?

It would be make sense to reference "clk" instead of "clocks".

> +static int init_clocks(struct device *dev,
> +		       const struct clk_bulk_caam *data)
> +{
> +	struct clk_bulk_data *clks;
> +	struct clk_bulk_caam *context;
> +	int num_clks;
> +	int ret;
> +
> +	num_clks = data->num_clks;
> +	clks = devm_kmemdup(dev, data->clks,
> +			    data->num_clks * sizeof(data->clks[0]),
> +			    GFP_KERNEL);
> +	if (!clks)
> +		return -ENOMEM;
> +
> +	ret = devm_clk_bulk_get(dev, num_clks, clks);
> +	if (ret) {
> +		dev_err(dev,
> +			"Failed to request all necessary clocks\n");
> +		return ret;
> +	}
> +
> +	ret = clk_bulk_prepare_enable(num_clks, clks);
> +	if (ret) {
> +		dev_err(dev,
> +			"Failed to prepare/enable all necessary clocks\n");
> +		return ret;
> +	}
> +
> +	context = devm_kzalloc(dev, sizeof(*context), GFP_KERNEL);
> +	if (!context)
> +		return -ENOMEM;

Aren't clks left enabled if this fails? Can move this allocation higher.

> +	context->num_clks = num_clks;
> +	context->clks = clks;
> +
> +	ret = devm_add_action_or_reset(dev, disable_clocks, context);
> +	if (ret)
> +		return ret;
> +
> +	return 0;
> +}

>   static int caam_probe(struct platform_device *pdev)
>   {
>   	int ret, ring, gen_sk, ent_delay = RTSDCTL_ENT_DLY_MIN;
>   	u64 caam_id;
> -	static const struct soc_device_attribute imx_soc[] = {
> -		{.family = "Freescale i.MX"},
> -		{},
> -	};
> +	const struct soc_device_attribute *soc_attr;

This "soc_attr" is difficult to understand, maybe rename to something 
like "imx_soc_match"?