On 05/15/2015 07:05 AM, Sascha Hauer wrote:
> On Wed, May 13, 2015 at 12:12:30PM +0200, Marc Kleine-Budde wrote:
>> This patch improves the backend property, it can be either a phandle or a
>> of_path. During probe() of the state driver the backend property is
>> dereferenced and the resulting of_path is saved in the state context. In a
>> later patch it will be used to generate a phandle reference to the backend
>> during DT fixup.
>>
>> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
>> ---
>>  common/state.c       |  9 ++++---
>>  drivers/misc/state.c | 70 ++++++++++++++++++++++++++++++++++++++++++----------
>>  include/state.h      |  7 +++---
>>  3 files changed, 67 insertions(+), 19 deletions(-)
>>
>> diff --git a/common/state.c b/common/state.c
>> index 744a6f8250c4..d6060bb7dff4 100644
>> --- a/common/state.c
>> +++ b/common/state.c
>> @@ -54,6 +54,7 @@ struct state_backend {
>>  	int (*load)(struct state_backend *backend, struct state *state);
>>  	int (*save)(struct state_backend *backend, struct state *state);
>>  	const char *name;
>> +	const char *of_path;
>>  	const char *path;
>>  };
>>  
>> @@ -903,7 +904,7 @@ out:
>>   * @state	The state instance to work on
>>   * @path	The path where the state will be stored to
>>   */
>> -int state_backend_dtb_file(struct state *state, const char *path)
>> +int state_backend_dtb_file(struct state *state, const char *of_path, const char *path)
>>  {
>>  	struct state_backend_dtb *backend_dtb;
>>  	struct state_backend *backend;
>> @@ -918,6 +919,7 @@ int state_backend_dtb_file(struct state *state, const char *path)
>>  
>>  	backend->load = state_backend_dtb_load;
>>  	backend->save = state_backend_dtb_save;
>> +	backend->of_path = xstrdup(of_path);
>>  	backend->path = xstrdup(path);
>>  	backend->name = "dtb";
>>  
>> @@ -1133,8 +1135,8 @@ out_free:
>>   * device @size may be 0. The two copies are spread to different
>>   * eraseblocks if approriate for this device.
>>   */
>> -int state_backend_raw_file(struct state *state, const char *path, off_t offset,
>> -		size_t size)
>> +int state_backend_raw_file(struct state *state, const char *of_path,
>> +		const char *path, off_t offset, size_t size)
>>  {
>>  	struct state_backend_raw *backend_raw;
>>  	struct state_backend *backend;
>> @@ -1159,6 +1161,7 @@ int state_backend_raw_file(struct state *state, const char *path, off_t offset,
>>  
>>  	backend->load = state_backend_raw_load;
>>  	backend->save = state_backend_raw_save;
>> +	backend->of_path = xstrdup(of_path);
>>  	backend->path = xstrdup(path);
>>  	backend->name = "raw";
>>  
>> diff --git a/drivers/misc/state.c b/drivers/misc/state.c
>> index 3b07bb93d725..9e8a40255348 100644
>> --- a/drivers/misc/state.c
>> +++ b/drivers/misc/state.c
>> @@ -24,10 +24,12 @@
>>  static int state_probe(struct device_d *dev)
>>  {
>>  	struct device_node *np = dev->device_node;
>> +	struct device_node *partition_node;
>>  	struct state *state;
>>  	const char *alias;
>>  	const char *backend_type = NULL;
>>  	int ret;
>> +	const char *of_path;
>>  	char *path;
>>  
>>  	if (!np)
>> @@ -41,28 +43,70 @@ static int state_probe(struct device_d *dev)
>>  	if (IS_ERR(state))
>>  		return PTR_ERR(state);
>>  
>> -	ret = of_find_path(np, "backend", &path, 0);
>> -	if (ret)
>> -		return ret;
>> +	of_path = of_get_property(np, "backend", NULL);
>> +	if (!of_path) {
>> +		ret = -ENODEV;
>> +		goto out_release;
>> +	}
>> +
>> +	/* guess if of_path is a path, not a phandle */
>> +	if (of_path[0] == '/') {
> 
> Since this also matches to the 47th phandle in the device tree I made
> this:
> 
> 	if (of_path[0] == '/' && len > 1)

Makes sense.

> And applied up to 6/7

Thanks,
Marc

-- 
Pengutronix e.K.                  | Marc Kleine-Budde           |
Industrial Linux Solutions        | Phone: +49-231-2826-924     |
Vertretung West/Dortmund          | Fax:   +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686  | http://www.pengutronix.de   |