Date: Mon, 4 Dec 2017 20:55:24 +0100
From: Ognjen Galic <smclt30p@gmail.com>
To: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Jonathan Corbet <corbet@lwn.net>, Len Brown <lenb@kernel.org>,
        Darren Hart <dvhart@infradead.org>,
        Andy Shevchenko <andy@infradead.org>,
        Henrique de Moraes Holschuh <ibm-acpi@hmh.eng.br>,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-acpi@vger.kernel.org, platform-driver-x86@vger.kernel.org,
        ibm-acpi-devel@lists.sourceforge.net
Subject: Re: [PATCH v2] thinkpad_acpi: Support the battery wear control
Message-ID: <20171204195524.GA25730@thinkpad>
References: <20171203225640.GA11655@thinkpad>
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On Mon, Dec 04, 2017 at 03:53:32PM +0100, Rafael J. Wysocki wrote:

> Not really.
> 
> This is generic code, so no thinkpad_acpi-specific stuff in this file, please,
> even under #ifdefs.
> 

I have some ideas, and I want your confirmation if that would be
acceptable.

Can I do this:

Expose a new API from battery.c for platform specific hooks:

struct battery_hook {
	int (*add_battery)(struct acpi_battery* battery);
	int (*remove_battery)(struct acpi_battery *battery);
};

battery_hook_register(struct battery_hook *hook)
battery_hook_unregister(struct battery_hook *hook)

When that hook is invoked from some other module, battery.c 
calls the add_battery method for each battery that is added and
remove_battery for each battery that is removed.

battery.c would keep a list of the battery_hook structs and invoke 
the add_battery and remove_battery methods as batteries get added 
and removed. 

With this API, we can add more hooks for battery features in 
the future, not just the ThinkPad hooks.

I hope you like the proposal :)