Re: [PATCH 3/3 v2] of/device: Register children with a compatible value in of_platform_bus_probe()

[Lan Chunhe <b25806@freescale.com>]

On Thu, 30 Dec 2010 14:50:45 +0800, Grant Likely  
<grant.likely@secretlab.ca> wrote:

> On Fri, Dec 10, 2010 at 06:52:20PM +0800, Lan Chunhe wrote:
>> Currently, of_platform_bus_probe() completely skips nodes which do not
>> explicitly match the 'matches' table passed in.  Or, if the root node
>> matches, then it registers all the children unconditionally.  However,
>> there are situations, such as registering devices from the root node,
>> when it is desirable to register child nodes, but only if they actually
>> represent devices.  For example, the root node may contain both a local
>> bus and a PCI device, but it also contains the chosen, aliases and cpus
>> nodes which don't represent real devices.
>>
>> This patch changes of_platform_bus_probe() to register all nodes at the
>> top level if they either match the matches table (the current  
>> behaviour),
>> or if they have a 'compatible' value (indicating it represents a  
>> device).
>>
>> Signed-off-by: Lan Chunhe <b25806@freescale.com>
>
> I believe this is my patch I wrote and pushed out to my tree back in
> October.  Was this cherry-picked out of the test-devicetree branch?

    Yes, I will add the signed off with you.

      Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
>> Signed-off-by: Lan Chunhe <b25806@freescale.com>

    At present I think that it is cherry-picked, and I have tested it which
    is OK.
    Do you have better method?

    Thanks.
    -Lan

>> ---
>>  drivers/of/platform.c |   28 +++++++++++++++++++++++-----
>>  1 files changed, 23 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
>> index 5b4a07f..02755ab 100644
>> --- a/drivers/of/platform.c
>> +++ b/drivers/of/platform.c
>> @@ -714,6 +714,8 @@ int of_platform_bus_probe(struct device_node *root,
>>  	struct device_node *child;
>>  	struct platform_device *dev;
>>  	int rc = 0;
>> +	const void *compat;
>> +	const struct of_device_id *match;
>>
>>  	if (WARN_ON(!matches || matches == OF_NO_DEEP_PROBE))
>>  		return -EINVAL;
>> @@ -741,16 +743,32 @@ int of_platform_bus_probe(struct device_node  
>> *root,
>>  		rc = of_platform_bus_create(root, matches, &dev->dev);
>>  		goto bail;
>>  	}
>> +
>> +	/*
>> +	 * Register each child node if either:
>> +	 *  a) it has a 'compatible' value indicating they are a device, or
>> +	 *  b) it is specified by the 'matches' table (by name or device_type)
>> +	 * If a node is specified in the matches table, then all its children
>> +	 * also get registered.
>> +	 */
>>  	for_each_child_of_node(root, child) {
>> -		if (!of_match_node(matches, child))
>> +		compat = of_get_property(child, "compatible", NULL);
>> +		match = of_match_node(matches, child);
>> +		if (!compat && !match)
>>  			continue;
>>
>> -		pr_debug("  match: %s\n", child->full_name);
>> +		pr_debug("  register device: %s\n", child->full_name);
>>  		dev = of_platform_device_create(child, NULL, parent);
>> -		if (dev == NULL)
>> +		if (!dev) {
>>  			rc = -ENOMEM;
>> -		else
>> -			rc = of_platform_bus_create(child, matches, &dev->dev);
>> +			of_node_put(child);
>> +			break;
>> +		}
>> +		if (!match)
>> +			continue;
>> +
>> +		pr_debug("  register children of: %s\n", child->full_name);
>> +		rc = of_platform_bus_create(child, matches, &dev->dev);
>>  		if (rc) {
>>  			of_node_put(child);
>>  			break;
>> --
>> 1.5.4.5
>>
>>
>