Re: [PATCH] of: property: special #nvmem-cell-cells handling

[Michael Walle <michael@walle.cc>]

Am 2022-11-18 22:52, schrieb Rob Herring:
> On Fri, Nov 18, 2022 at 3:40 PM Michael Walle <michael@walle.cc> wrote:
>> 
>> Since recently, there is a new #nvmem-cell-cells. To be backwards
>> compatible this is optional. Therefore, we need special handling and
>> cannot use DEFINE_SIMPLE_PROP() anymore.
>> 
>> Signed-off-by: Michael Walle <michael@walle.cc>
>> ---
>> This patch will be part of the following series:
>> https://lore.kernel.org/linux-arm-kernel/20221118185118.1190044-1-michael@walle.cc/
>> 
>>  drivers/of/property.c | 17 ++++++++++++++++-
>>  1 file changed, 16 insertions(+), 1 deletion(-)
>> 
>> diff --git a/drivers/of/property.c b/drivers/of/property.c
>> index 967f79b59016..93c0ea662336 100644
>> --- a/drivers/of/property.c
>> +++ b/drivers/of/property.c
>> @@ -1305,7 +1305,6 @@ DEFINE_SIMPLE_PROP(dmas, "dmas", "#dma-cells")
>>  DEFINE_SIMPLE_PROP(power_domains, "power-domains", 
>> "#power-domain-cells")
>>  DEFINE_SIMPLE_PROP(hwlocks, "hwlocks", "#hwlock-cells")
>>  DEFINE_SIMPLE_PROP(extcon, "extcon", NULL)
>> -DEFINE_SIMPLE_PROP(nvmem_cells, "nvmem-cells", NULL)
>>  DEFINE_SIMPLE_PROP(phys, "phys", "#phy-cells")
>>  DEFINE_SIMPLE_PROP(wakeup_parent, "wakeup-parent", NULL)
>>  DEFINE_SIMPLE_PROP(pinctrl0, "pinctrl-0", NULL)
>> @@ -1381,6 +1380,22 @@ static struct device_node 
>> *parse_interrupts(struct device_node *np,
>>         return of_irq_parse_one(np, index, &sup_args) ? NULL : 
>> sup_args.np;
>>  }
>> 
>> +static struct device_node *parse_nvmem_cells(struct device_node *np,
>> +                                            const char *prop_name, 
>> int index)
>> +{
>> +       struct of_phandle_args sup_args;
>> +
>> +       if (strcmp(prop_name, "nvmem-cells"))
>> +               return NULL;
>> +
>> +       if (of_parse_phandle_with_optional_args(np, prop_name,
>> +                                               "#nvmem-cell-cells", 
>> index,
>> +                                               &sup_args))
>> +               return NULL;
>> +
>> +       return sup_args.np;
>> +}
> 
> There's a couple of other cases like that (MSI IIRC), so can we
> generalize this to work in more than 1 case?

You mean addding a new DEFINE_SIMPLE_PROP_OPTIONAL_ARGS()?

-michael