[RFC 3/3] olpc-battery: bind to device tree

[Grant Likely]

On Fri, Mar 04, 2011 at 05:12:40PM +0000, Daniel Drake wrote:
> This is cleaner, and allows suspend/resume (wakeup) handlers to be
> added in an upcoming patch.
> 
> Signed-off-by: Daniel Drake <dsd at laptop.org>

Hi Daniel,

A few minor comments below...

> ---
>  drivers/power/olpc_battery.c |   55 ++++++++++++++++++++++++++----------------
>  1 files changed, 34 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/power/olpc_battery.c b/drivers/power/olpc_battery.c
> index 0b0ff3a..dc1526e 100644
> --- a/drivers/power/olpc_battery.c
> +++ b/drivers/power/olpc_battery.c
> @@ -519,9 +519,8 @@ static struct device_attribute olpc_bat_error = {
>   *		Initialisation
>   *********************************************************************/
>  
> -static struct platform_device *bat_pdev;
> -
>  static struct power_supply olpc_bat = {
> +	.name = "olpc-battery",
>  	.get_property = olpc_bat_get_property,
>  	.use_for_apm = 1,
>  };
> @@ -534,14 +533,11 @@ void olpc_battery_trigger_uevent(unsigned long cause)
>  		kobject_uevent(&olpc_bat.dev->kobj, KOBJ_CHANGE);
>  }
>  
> -static int __init olpc_bat_init(void)
> +static int __devinit olpc_battery_probe(struct platform_device *pdev)
>  {
> -	int ret = 0;
> +	int ret;
>  	uint8_t status;
>  
> -	if (!olpc_platform_info.ecver)
> -		return -ENXIO;
> -
>  	/*
>  	 * We've seen a number of EC protocol changes; this driver requires
>  	 * the latest EC protocol, supported by 0x44 and above.
> @@ -558,15 +554,10 @@ static int __init olpc_bat_init(void)
>  
>  	/* Ignore the status. It doesn't actually matter */
>  
> -	bat_pdev = platform_device_register_simple("olpc-battery", 0, NULL, 0);
> -	if (IS_ERR(bat_pdev))
> -		return PTR_ERR(bat_pdev);
> -
> -	ret = power_supply_register(&bat_pdev->dev, &olpc_ac);
> +	ret = power_supply_register(&pdev->dev, &olpc_ac);
>  	if (ret)
> -		goto ac_failed;
> +		return ret;
>  
> -	olpc_bat.name = bat_pdev->name;
>  	if (olpc_board_at_least(olpc_board_pre(0xd0))) { /* XO-1.5 */
>  		olpc_bat.properties = olpc_xo15_bat_props;
>  		olpc_bat.num_properties = ARRAY_SIZE(olpc_xo15_bat_props);
> @@ -575,7 +566,7 @@ static int __init olpc_bat_init(void)
>  		olpc_bat.num_properties = ARRAY_SIZE(olpc_xo1_bat_props);
>  	}
>  
> -	ret = power_supply_register(&bat_pdev->dev, &olpc_bat);
> +	ret = power_supply_register(&pdev->dev, &olpc_bat);
>  	if (ret)
>  		goto battery_failed;
>  
> @@ -587,7 +578,7 @@ static int __init olpc_bat_init(void)
>  	if (ret)
>  		goto error_failed;
>  
> -	goto success;
> +	return 0;
>  
>  error_failed:
>  	device_remove_bin_file(olpc_bat.dev, &olpc_bat_eeprom);
> @@ -595,19 +586,41 @@ eeprom_failed:
>  	power_supply_unregister(&olpc_bat);
>  battery_failed:
>  	power_supply_unregister(&olpc_ac);
> -ac_failed:
> -	platform_device_unregister(bat_pdev);
> -success:
>  	return ret;
>  }
>  
> -static void __exit olpc_bat_exit(void)
> +static int __devexit olpc_battery_remove(struct platform_device *pdev)
>  {
>  	device_remove_file(olpc_bat.dev, &olpc_bat_error);
>  	device_remove_bin_file(olpc_bat.dev, &olpc_bat_eeprom);
>  	power_supply_unregister(&olpc_bat);
>  	power_supply_unregister(&olpc_ac);
> -	platform_device_unregister(bat_pdev);
> +	return 0;
> +}
> +
> +static const struct of_device_id olpc_battery_ids[] __devinitconst = {
> +	{ .compatible = "olpc,xo1-battery" },

I want to see all new compatible properties documented in
Documentation/devicetree/bindings.  It may not be the best place for
binding documentation since it is currently tied to Linux, but it is
better than anything else we currently have.

> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, olpc_battery_ids);
> +
> +static struct platform_driver olpc_battery_drv = {
> +	.driver = {
> +		.name = "olpc-battery",
> +		.owner = THIS_MODULE,
> +		.of_match_table = olpc_battery_ids,
> +	},
> +	.probe = olpc_battery_probe,
> +	.remove = __devexit_p(olpc_battery_remove),
> +};
> +
> +static int __init olpc_bat_init(void)
> +{
> +	return platform_driver_register(&olpc_battery_drv);
> +}
> +static void __exit olpc_bat_exit(void)
> +{
> +	platform_driver_unregister(&olpc_battery_drv);
>  }
>  
>  module_init(olpc_bat_init);

Personally, I prefer to see the module_init() and module_exit()
registrations immediately after the functions they register, like so:

static int __init olpc_bat_init(void)
{
	return platform_driver_register(&olpc_battery_drv);
}
module_init(olpc_bat_init);

static void __exit olpc_bat_exit(void)
{
	platform_driver_unregister(&olpc_battery_drv);
}
module_exit(olpc_bat_exit);