Re: [PATCH v4 01/34] component: Introduce struct aggregate_device

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Thu, Dec 02, 2021 at 02:26:59PM -0800, Stephen Boyd wrote:
> Replace 'struct master' with 'struct aggregate_device' and then rename
> 'master' to 'adev' everywhere in the code. While we're here, put a
> struct device inside the aggregate device so that we can register it
> with a bus_type in the next patch.
> 
> The diff is large but that's because this is mostly a rename, where
> sometimes 'master' is replaced with 'adev' and other times it is
> replaced with 'parent' to indicate that the struct device that was being
> used is actually the parent of the aggregate device and driver.
> 
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Cc: "Rafael J. Wysocki" <rafael@kernel.org>
> Cc: Rob Clark <robdclark@gmail.com>
> Cc: Russell King <rmk+kernel@arm.linux.org.uk>
> Cc: Saravana Kannan <saravanak@google.com>
> Signed-off-by: Stephen Boyd <swboyd@chromium.org>
> ---
>  drivers/base/component.c | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/base/component.c b/drivers/base/component.c
> index 2d25a6416587..d25048d04b70 100644
> --- a/drivers/base/component.c
> +++ b/drivers/base/component.c
> @@ -9,6 +9,7 @@
>   */
>  #include <linux/component.h>
>  #include <linux/device.h>
> +#include <linux/idr.h>
>  #include <linux/list.h>
>  #include <linux/mutex.h>
>  #include <linux/slab.h>
> @@ -63,7 +64,10 @@ struct master {
>  
>  	const struct component_master_ops *ops;
>  	struct device *parent;
> +	struct device dev;

Who initializes this new structure?

>  	struct component_match *match;
> +
> +	int id;
>  };
>  
>  struct component {
> @@ -79,6 +83,7 @@ struct component {
>  static DEFINE_MUTEX(component_mutex);
>  static LIST_HEAD(component_list);
>  static LIST_HEAD(masters);
> +static DEFINE_IDA(aggregate_ida);
>  
>  #ifdef CONFIG_DEBUG_FS
>  
> @@ -440,6 +445,7 @@ static void free_master(struct master *master)
>  		}
>  	}
>  
> +	ida_free(&aggregate_ida, master->id);
>  	kfree(master);
>  }
>  
> @@ -460,7 +466,7 @@ int component_master_add_with_match(struct device *parent,
>  	struct component_match *match)
>  {
>  	struct master *master;
> -	int ret;
> +	int ret, id;
>  
>  	/* Reallocate the match array for its true size */
>  	ret = component_match_realloc(match, match->num);
> @@ -471,9 +477,17 @@ int component_master_add_with_match(struct device *parent,
>  	if (!master)
>  		return -ENOMEM;
>  
> +	id = ida_alloc(&aggregate_ida, GFP_KERNEL);
> +	if (id < 0) {
> +		kfree(master);
> +		return id;
> +	}
> +
> +	master->id = id;
>  	master->parent = parent;
>  	master->ops = ops;
>  	master->match = match;
> +	dev_set_name(&master->dev, "aggregate%d", id);

You set the name yet the device is not "real"?

I don't understand this patch at all, sorry.

greg k-h