From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mark Brown <broonie@opensource.wolfsonmicro.com>
Date: Thu, 16 Aug 2012 14:14:19 +0000
Subject: Re: [PATCH v4 1/3] Runtime Interpreted Power Sequences
Message-Id: <20120816141418.GL15365@opensource.wolfsonmicro.com>
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 <1345097337-24170-2-git-send-email-acourbot@nvidia.com>
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To: Alexandre Courbot <acourbot@nvidia.com>
Cc: Stephen Warren <swarren@nvidia.com>, Thierry Reding <thierry.reding@avionic-design.de>, Simon Glass <sjg@chromium.org>, Grant Likely <grant.likely@secretlab.ca>, Rob Herring <rob.herring@calxeda.com>, Anton Vorontsov <cbou@mail.ru>, David Woodhouse <dwmw2@infradead.org>, Arnd Bergmann <arnd@arndb.de>, Leela Krishna Amudala <leelakrishna.a@gmail.com>, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fbdev@vger.kernel.org, devicetree-discuss@lists.ozlabs.org, linux-doc@vger.kernel.org

On Thu, Aug 16, 2012 at 03:08:55PM +0900, Alexandre Courbot wrote:

> +		power-off-sequence {
> +			step0 {
> +				gpio = "enable";
> +				disable;

I'd change the name to "reset" or something in the example - avoids any
confusion with the action.

> +#ifdef CONFIG_REGULATOR
> +	case POWER_SEQ_REGULATOR:
> +		if (pdata->regulator.enable)
> +			err = regulator_enable(step->resource->regulator);
> +		else
> +			err = regulator_disable(step->resource->regulator);
> +		break;

The regulator and GPIO APIs should stub themselves out adequately to not
need the ifdefs at least for regulator I'd use the stubs since...

> +	/*
> +	 * should never happen unless the sequence includes a step which
> +	 * type does not have support compiled in
> +	 */
> +	default:
> +		return -EINVAL;

...this probably isn't what's meant.  It might also be nice to have
support for bulk_enable() but that's definitely something that could be
added later.

> +		err = power_seq_step_run(&seq->steps[cpt]);
> +		if (err) {
> +			dev_err(dev, "error %d while running power sequence!\n",
> +				err);
> +			return err;

I'd also log at least the step number, it'll make diagnostics easier.