Re: [PATCH 1/7] driver-core : add class iteration api

[Jarek Poplawski <jarkao2@gmail.com>]

On Sat, Jan 12, 2008 at 05:47:54PM +0800, Dave Young wrote:
> Add the following class iteration functions for driver use:
> class_for_each_device
> class_find_device
> class_for_each_child
> class_find_child
> 
> Signed-off-by: Dave Young <hidave.darkstar@gmail.com> 
> 
> ---
>  drivers/base/class.c   |  159 +++++++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/device.h |    8 ++
>  2 files changed, 167 insertions(+)
> 
> diff -upr linux/drivers/base/class.c linux.new/drivers/base/class.c
> --- linux/drivers/base/class.c	2008-01-12 14:42:24.000000000 +0800
> +++ linux.new/drivers/base/class.c	2008-01-12 14:42:24.000000000 +0800
> @@ -798,6 +798,165 @@ void class_device_put(struct class_devic
>  		kobject_put(&class_dev->kobj);
>  }
>  
> +/**
> + *	class_for_each_device - device iterator
> + *	@class:	the class we're iterating
> + *	@data: data for the callback
> + *	@fn: function to be called for each device
> + *
> + *	Iterate over @class's list of devices, and call @fn for each,
> + *	passing it @data.
> + *
> + *	We check the return of @fn each time. If it returns anything
> + *	other than 0, we break out and return that value.
> + */
> +int class_for_each_device(struct class *class, void *data,
> +			   int (*fn)(struct device *, void *))
> +{
> +	struct device *dev;
> +	int error = 0;
> +
> +	if (!class)
> +		return -EINVAL;
> +	down(&class->sem);
> +	list_for_each_entry(dev, &class->devices, node) {

Probably some tiny oversight, but I see this comment to struct class
doesn't mention devices list, so maybe this needs to be updated BTW?:

(from include/linux/device.h)
"        struct semaphore        sem;    /* locks both the children and interfaces lists */"

Regards,
Jarek P.