[RFC v2 5/5] drm/dsi: Get DSI host by DT device node

[Archit Taneja]

On 11/02/2015 04:20 PM, Andrzej Hajda wrote:
> On 10/06/2015 11:24 AM, Archit Taneja wrote:
>> mipi_dsi_devices are inherently aware of their host because they
>> share a parent-child hierarchy in the device tree.
>>
>> Non-dsi drivers that create a dummy dsi device don't have this data.
>> In order to get this information, they require to a phandle to the dsi
>> host in the device tree.
>>
>> Maintain a list of all the hosts DSI that are currently registered.
>>
>> This list will be used to find the mipi_dsi_host corresponding to the
>> device_node passed in of_find_mipi_dsi_host_by_node.
>>
>> Signed-off-by: Archit Taneja <architt at codeaurora.org>
>
> Looks OK, beside lack of documentation, after fixing it you can add
> Reviewed-by: Andrzej Hajda <a.hajda at samsung.com>

I will add missing documentation before posting v3.

Thanks again for the review.

Archit

>
> Regards
> Andrzej
>
>> ---
>>   drivers/gpu/drm/drm_mipi_dsi.c | 30 ++++++++++++++++++++++++++++++
>>   include/drm/drm_mipi_dsi.h     |  2 ++
>>   2 files changed, 32 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
>> index cbb7373..c51d73e 100644
>> --- a/drivers/gpu/drm/drm_mipi_dsi.c
>> +++ b/drivers/gpu/drm/drm_mipi_dsi.c
>> @@ -216,6 +216,28 @@ of_mipi_dsi_device_add(struct mipi_dsi_host *host, struct device_node *node)
>>   	return mipi_dsi_device_new(host, &info);
>>   }
>>
>> +static DEFINE_MUTEX(host_lock);
>> +static LIST_HEAD(host_list);
>> +
>> +struct mipi_dsi_host *of_find_mipi_dsi_host_by_node(struct device_node *node)
>> +{
>> +	struct mipi_dsi_host *host;
>> +
>> +	mutex_lock(&host_lock);
>> +
>> +	list_for_each_entry(host, &host_list, list) {
>> +		if (host->dev->of_node == node) {
>> +			mutex_unlock(&host_lock);
>> +			return host;
>> +		}
>> +	}
>> +
>> +	mutex_unlock(&host_lock);
>> +
>> +	return NULL;
>> +}
>> +EXPORT_SYMBOL(of_find_mipi_dsi_host_by_node);
>> +
>>   int mipi_dsi_host_register(struct mipi_dsi_host *host)
>>   {
>>   	struct device_node *node;
>> @@ -227,6 +249,10 @@ int mipi_dsi_host_register(struct mipi_dsi_host *host)
>>   		of_mipi_dsi_device_add(host, node);
>>   	}
>>
>> +	mutex_lock(&host_lock);
>> +	list_add_tail(&host->list, &host_list);
>> +	mutex_unlock(&host_lock);
>> +
>>   	return 0;
>>   }
>>   EXPORT_SYMBOL(mipi_dsi_host_register);
>> @@ -243,6 +269,10 @@ static int mipi_dsi_remove_device_fn(struct device *dev, void *priv)
>>   void mipi_dsi_host_unregister(struct mipi_dsi_host *host)
>>   {
>>   	device_for_each_child(host->dev, NULL, mipi_dsi_remove_device_fn);
>> +
>> +	mutex_lock(&host_lock);
>> +	list_del_init(&host->list);
>> +	mutex_unlock(&host_lock);
>>   }
>>   EXPORT_SYMBOL(mipi_dsi_host_unregister);
>>
>> diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h
>> index 68f49f4..15d3068 100644
>> --- a/include/drm/drm_mipi_dsi.h
>> +++ b/include/drm/drm_mipi_dsi.h
>> @@ -100,10 +100,12 @@ struct mipi_dsi_host_ops {
>>   struct mipi_dsi_host {
>>   	struct device *dev;
>>   	const struct mipi_dsi_host_ops *ops;
>> +	struct list_head list;
>>   };
>>
>>   int mipi_dsi_host_register(struct mipi_dsi_host *host);
>>   void mipi_dsi_host_unregister(struct mipi_dsi_host *host);
>> +struct mipi_dsi_host *of_find_mipi_dsi_host_by_node(struct device_node *node);
>>
>>   /* DSI mode flags */
>>
>

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