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regulator_register() API

From:  Rodolfo Giometti <>
To:  Liam Girdwood <>, Mark Brown <>
Subject:  regulator_register() API
Date:  Tue, 9 Jun 2009 15:59:47 +0200
Message-ID:  <>
Archive-link:  Article


I'm trying to add the regulator support to my driver for max8821
(white led charge pump with mono class D audio amp and dual LDO).

Current regulator_register() implementation forces the caller to
allocate a proper device for each regulators and also the line:

   struct regulator_init_data *init_data = dev->platform_data;

forces the user to define the pointer platform_data as a "struct
regulator_init_data" only.

Since max8821 has both leds and LDOs I compared the functions
regulator_register() and led_classdev_register() and IMHO the latter
is more versatile/easy-to-use than the former. :)

In a multifunctional device connected with an I2C bus (as the max8821
is) it's quite complex defining a regulator device since I must
provide a new device for each regulators and redefing platform_data
for each registration.

However if the regulator_register() worked in a similar way to
led_classdev_register(), I simply can do something like this:

        for (i = 0; i < regulators_num; i++) {
	       /* init regulators structs */

               ret = regulator_register(&client->dev, &reg[i].dev);
               if (ret < 0)
		       dev_warn(&client->dev, "unable to register\n");

and writing the support for my multifunctional device will be
easier. :)

What about if I add a new function regulator_classdev_register() which
in turn calls regulator_register() doing in a similar way than
led_classdev_register() does?

This will keep backward compatibility with old drivers and may offer a
more versatile way to define a regulator expecially for
multifunctional devices.




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