Re: Re[4]: [PATCH v3] mfd: syscon: Add non-DT support

From: Dong Aisheng
Date: Tue Feb 19 2013 - 04:58:50 EST


On 19 February 2013 16:56, Alexander Shiyan <shc_work@xxxxxxx> wrote:
> ...
>> >> >> struct regmap *syscon_regmap_lookup_by_compatible(const char *s)
>> >> >> {
>> >> >> struct device_node *syscon_np;
>> >> >> struct regmap *regmap;
>> >> >> + struct syscon *syscon;
>> >> >> + struct device *dev;
>> >> >>
>> >> >> syscon_np = of_find_compatible_node(NULL, NULL, s);
>> >> >> - if (!syscon_np)
>> >> >> + if (syscon_np) {
>> >> >> + regmap = syscon_node_to_regmap(syscon_np);
>> >> >> + of_node_put(syscon_np);
>> >> >> +
>> >> >> + return regmap;
>> >> >> + }
>> >> >> +
>> >> >> + /* Fallback to search by id_entry.name string */
>> >> >> + dev = driver_find_device(&syscon_driver.driver, NULL, (void *)s,
>> >> >> + syscon_match_id);
>> >> >> + if (!dev)
>> >> >> return ERR_PTR(-ENODEV);
>> >> >>
>> >> >> - regmap = syscon_node_to_regmap(syscon_np);
>> >> >> - of_node_put(syscon_np);
>> >> >> + syscon = dev_get_drvdata(dev);
>> >> >>
>> >> >> - return regmap;
>> >> >> + return syscon->regmap;
>> >> >> }
>> >> >> EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_compatible);
>> >> >
>> >> > Since you are not actually comparing the "compatible" property here,
>> >> > I would suggest adding another function here,
>> >>
>> >> Yes, i also think like that.
>> >
>> > In this case we should provide two paths for drivers which can work as with DT
>> > and without DT.
>>
>> Yes.
>
> I still think the universal procedure is better for the driver.
>

Why?
I did not see your reply on my other comments on the problems of using universal
procedure?
Please let me know if you think they're not issues.

>> > In my case we can use platform_device_id.name field with
>> > "compatible" string. My way in this case is transparency for driver which is
>> > using "syscon".
>> >
>>
>> Yes, but it also brings misleading and mass.
>> And i wonder even the API can cover the two type of matches, the
>> caller still can't use
>> the only one name for two cases since the name is different.
>> So it looks to me not make too much sense to provide only one API.
>
> The previous version of the patch keep conformity to the name of
> procedure ("compatible" field in platform_data)...
>
> So, now I'm totally confused what we do with the search function.
>

You can do as you currently do but with a different API for non-dt.

Regards
Dong Aisheng
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/