linux-kernel - Re: [PATCH 2/2] regulator: Add Freescale's MC34708 regulators

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: <20120420114201.GA3259@opensource.wolfsonmicro.com>
Date:	Fri, 20 Apr 2012 12:42:01 +0100
From:	Mark Brown <broonie@...nsource.wolfsonmicro.com>
To:	"Ying-Chun Liu (PaulLiu)" <paul.liu@...aro.org>
Cc:	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
	linaro-dev@...ts.linaro.org, patches@...aro.org,
	Robin Gong <B38343@...escale.com>, Liam Girdwood <lrg@...com>,
	Samuel Ortiz <sameo@...ux.intel.com>,
	Shawn Guo <shawn.guo@...aro.org>
Subject: Re: [PATCH 2/2] regulator: Add Freescale's MC34708 regulators

On Fri, Apr 20, 2012 at 12:38:41AM +0800, Ying-Chun Liu (PaulLiu) wrote:

> +static const int mc34708_sw1A[] = {
> +	650000, 662500, 675000, 687500, 700000, 712500,

Replace these by direct calculations, using tables is both less
efficient and less clear.

> +	mc34708_lock(priv->mc34708);
> +	ret = mc34708_reg_rmw(priv->mc34708, mc34708_regulators[id].reg,
> +			      mc34708_regulators[id].enable_bit,
> +			      mc34708_regulators[id].enable_bit);
> +	mc34708_unlock(priv->mc34708);

Having to open code this locking in every single driver is a bit
painful; just have the default register I/O operations do the locking
and introduce additional unlocked versions if needed.

All this stuff could be factored out if you were using regmap.

> +EXPORT_SYMBOL_GPL(mc34708_regulator_list_voltage);

No, this stuff should only be accessed via the ops.  Why are you doing
this?

> +int
> +mc34708_get_best_voltage_index(struct regulator_dev *rdev,
> +			       int min_uV, int max_uV)
> +{

You're reimplementing core functionality here, or it'd be even better to
use calculations.

> +static int mc34708_regulator_get_voltage(struct regulator_dev *rdev)
> +{

Why is this not get_voltage_sel?

> +static struct regulator_ops mc34708_regulator_ops = {
> +	.enable = mc34708_regulator_enable,
> +	.disable = mc34708_regulator_disable,
> +	.is_enabled = mc34708_regulator_is_enabled,
> +	.list_voltage = mc34708_regulator_list_voltage,
> +	.set_voltage = mc34708_regulator_set_voltage,
> +	.get_voltage = mc34708_regulator_get_voltage,
> +};
> +EXPORT_SYMBOL_GPL(mc34708_regulator_ops);

No.  What are you doing this for?

> +int
> +mc34708_fixed_regulator_set_voltage(struct regulator_dev *rdev, int min_uV,
> +				    int max_uV, unsigned *selector)

This function makes no sense...

> +int mc34708_sw_regulator_is_enabled(struct regulator_dev *rdev)
> +{
> +	return 1;
> +}

Why are you doing this - this function is redundant.

> +	ret = mc34708_reg_rmw(mc34708, MC34708_SW12OP,
> +			      MC34708_SW12OP_SW1AMODE_M |
> +			      MC34708_SW12OP_SW2MODE_M,
> +			      MC34708_SW12OP_SW1AMODE_VALUE |
> +			      MC34708_SW12OP_SW2MODE_VALUE);
> +	if (ret)
> +		goto err_free;
> +
> +	ret = mc34708_reg_rmw(mc34708, MC34708_SW345OP,
> +			      MC34708_SW345OP_SW3MODE_M |
> +			      MC34708_SW345OP_SW4AMODE_M |
> +			      MC34708_SW345OP_SW4BMODE_M |
> +			      MC34708_SW345OP_SW5MODE_M,
> +			      MC34708_SW345OP_SW3MODE_VALUE |
> +			      MC34708_SW345OP_SW4AMODE_VALUE |
> +			      MC34708_SW345OP_SW4BMODE_VALUE |
> +			      MC34708_SW345OP_SW5MODE_VALUE);
> +	if (ret)
> +		goto err_free;

If this needs to be done unconditionally shouldn't it be being donei in
the MFD core driver?

Download attachment "signature.asc" of type "application/pgp-signature" (837 bytes)