On 09.08.22 09:26, Marco Felsch wrote:
> Hi Ahmad,
>
> On 22-08-09, Ahmad Fatoum wrote:
>> board code fix up the device tree for OS consumption. Sometimes it's
>> useful for the fixup to append onto an existing property.
>> Add a helper that simplifies this.
>
> do you have a particular use-case for this?
I have two boards that aren't yet upstream with board support
code using this:
- One uses it to append onto the model string information about the
SoM revision
- One parses a format from an EEPROM and fixes up the device tree
accordingly. If it encounters the same tag twice, it appends
onto the previous property instead of overwriting.
I figured if I needed it twice, it can be useful to others as well.
The tests should ensure it doesn't bit rot until hardware is
finalized and board support is upstreamed.
Cheers,
Ahmad
>
> Regards,
> Marco
>
>> Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
>> ---
>> drivers/of/base.c | 36 ++++++++++++++++++++++++++++++++++++
>> include/of.h | 8 ++++++++
>> 2 files changed, 44 insertions(+)
>>
>> diff --git a/drivers/of/base.c b/drivers/of/base.c
>> index 101b2f74c74f..0893bdf3e04f 100644
>> --- a/drivers/of/base.c
>> +++ b/drivers/of/base.c
>> @@ -2321,6 +2321,42 @@ int of_set_property(struct device_node *np, const char *name, const void *val, i
>> return 0;
>> }
>>
>> +int of_append_property(struct device_node *np, const char *name, const void *val, int len)
>> +{
>> + struct property *pp;
>> + void *buf = NULL;
>> + int orig_len = 0;
>> +
>> + if (!np)
>> + return -ENOENT;
>> +
>> + pp = of_find_property(np, name, NULL);
>> + if (pp) {
>> + buf = pp->value;
>> + orig_len = pp->length;
>> + }
>> +
>> + buf = realloc(buf, orig_len + len);
>> + if (!buf)
>> + return -ENOMEM;
>> +
>> + memcpy(buf + orig_len, val, len);
>> +
>> + if (pp) {
>> + pp->value = buf;
>> + pp->length += len;
>> +
>> + if (pp->value_const) {
>> + memcpy(buf, pp->value_const, orig_len);
>> + pp->value_const = NULL;
>> + }
>> + } else {
>> + pp = __of_new_property(np, name, buf, len);
>> + }
>> +
>> + return 0;
>> +}
>> +
>> int of_property_sprintf(struct device_node *np,
>> const char *propname, const char *fmt, ...)
>> {
>> diff --git a/include/of.h b/include/of.h
>> index c65cef5a5a7c..97b4b3dd79bd 100644
>> --- a/include/of.h
>> +++ b/include/of.h
>> @@ -131,6 +131,8 @@ extern struct device_node *of_get_cpu_node(int cpu, unsigned int *thread);
>>
>> extern int of_set_property(struct device_node *node, const char *p,
>> const void *val, int len, int create);
>> +extern int of_append_property(struct device_node *np, const char *p,
>> + const void *val, int len);
>> extern struct property *of_new_property(struct device_node *node,
>> const char *name, const void *data, int len);
>> extern struct property *of_new_property_const(struct device_node *node,
>> @@ -515,6 +517,12 @@ static inline int of_set_property(struct device_node *node, const char *p,
>> return -ENOSYS;
>> }
>>
>> +static inline int of_append_property(struct device_node *np, const char *p,
>> + const void *val, int len)
>> +{
>> + return -ENOSYS;
>> +}
>> +
>> static inline struct property *of_new_property(struct device_node *node,
>> const char *name, const void *data, int len)
>> {
>> --
>> 2.30.2
>>
>>
>>
>
--
Pengutronix e.K. | |
Steuerwalder Str. 21 | http://www.pengutronix.de/ |
31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
