[U-Boot] [PATCH 2/3] core: Add functions to set properties in live-tree

[Mario Six]

Hi Simon,

On Thu, Apr 12, 2018 at 6:42 PM, Simon Glass <sjg at chromium.org> wrote:
> Hi Mario,
>
> On 10 April 2018 at 05:23, Mario Six <mario.six at gdsys.cc> wrote:
>> Hi Simon,
>>
>> On Fri, Mar 30, 2018 at 12:43 AM, Simon Glass <sjg at chromium.org> wrote:
>>> Hi Mario,
>>>
>>> On 28 March 2018 at 20:37, Mario Six <mario.six at gdsys.cc> wrote:
>>>> Implement a set of functions to manipulate properties in a live device
>>>> tree:
>>>>
>>>> * ofnode_set_property() to set generic properties of a node
>>>> * ofnode_write_string() to set string properties of a node
>>>> * ofnode_enable() to enable a node
>>>> * ofnode_disable() to disable a node
>>>>
>>>
>>> Please add a test for these functions.
>>>
>>>> Signed-off-by: Mario Six <mario.six at gdsys.cc>
>>>> ---
>>>>  drivers/core/ofnode.c | 58 +++++++++++++++++++++++++++++++++++++++++++++++++++
>>>>  include/dm/ofnode.h   | 49 +++++++++++++++++++++++++++++++++++++++++++
>>>>  2 files changed, 107 insertions(+)
>>>>
>>>> diff --git a/drivers/core/ofnode.c b/drivers/core/ofnode.c
>>>> index ca002063b3..90d05aa559 100644
>>>> --- a/drivers/core/ofnode.c
>>>> +++ b/drivers/core/ofnode.c
>>>> @@ -699,3 +699,61 @@ u64 ofnode_translate_address(ofnode node, const fdt32_t *in_addr)
>>>>         else
>>>>                 return fdt_translate_address(gd->fdt_blob, ofnode_to_offset(node), in_addr);
>>>>  }
>>>> +
>>>> +#ifdef CONFIG_OF_LIVE
>>>
>>> Is this needed?
>>>
>>
>> See below, these functions don't make sense if there is no livetree.
>
> Right, but they should still compile?
>
>>
>>>> +int ofnode_set_property(ofnode node, const char *propname, int len,
>>>> +                       const void *value)
>>>> +{
>>>> +       const struct device_node *np = ofnode_to_np(node);
>>>> +       struct property *pp;
>>>> +       struct property *new;
>>>> +
>>>> +       if (!np)
>>>> +               return -EINVAL;
>>>> +
>>>> +       for (pp = np->properties; pp; pp = pp->next) {
>>>> +               if (strcmp(pp->name, propname) == 0) {
>>>> +                       /* Property exists -> change value */
>>>> +                       pp->value = (void *)value;
>>>> +                       pp->length = len;
>>>> +                       return 0;
>>>> +               }
>>>> +       }
>>>> +
>>>> +       /* Property does not exist -> append new property */
>>>> +       new = malloc(sizeof(struct property));
>>>> +
>>>> +       new->name = strdup(propname);
>>>> +       new->value = malloc(len);
>>>> +       memcpy(new->value, value, len);
>>>> +       new->length = len;
>>>> +       new->next = NULL;
>>>> +
>>>> +       pp->next = new;
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +int ofnode_write_string(ofnode node, const char *propname, const char *value)
>>>> +{
>>>> +       assert(ofnode_valid(node));
>>>
>>> What does this function do if livetree is not enabled?
>>>
>>
>> The idea was to not make them available if livetree is not enabled (hence the
>> #ifdef CONFIG_OF_LIVE).
>>
>> Making them nops in case livetree is not available would work as well if
>> that's preferable.
>
> Yes. Then they could return -ENOSYS, for example. Then we at least
> have a consistent API for both live/flat tree, instead of them
> splitting away from each other.
>

OK, I'll use that approach in v2.

>>
>>>> +       debug("%s: %s = %s", __func__, propname, value);
>>>> +
>>>> +       return ofnode_set_property(node, propname, strlen(value) + 1, value);
>>>> +}
>>>> +
>>>> +int ofnode_enable(ofnode node)
>>>> +{
>>>> +       assert(ofnode_valid(node));
>>>> +
>>>> +       return ofnode_write_string(node, "status", "okay");
>>>> +}
>>>> +
>>>> +int ofnode_disable(ofnode node)
>>>> +{
>>>> +       assert(ofnode_valid(node));
>>>> +
>>>> +       return ofnode_write_string(node, "status", "disable");
>>>> +}
>>>> +
>>>> +#endif
>>>> diff --git a/include/dm/ofnode.h b/include/dm/ofnode.h
>>>> index aec205eb80..e82ebf19c5 100644
>>>> --- a/include/dm/ofnode.h
>>>> +++ b/include/dm/ofnode.h
>>>> @@ -689,4 +689,53 @@ int ofnode_read_resource_byname(ofnode node, const char *name,
>>>>   * @return the translated address; OF_BAD_ADDR on error
>>>>   */
>>>>  u64 ofnode_translate_address(ofnode node, const fdt32_t *in_addr);
>>>> +
>>>> +#ifdef CONFIG_OF_LIVE
>>>> +
>>>> +/**
>>>> + * ofnode_set_property() - Set a property of a ofnode
>>>> + *
>>>> + * @node:      The node for whose property should be set
>>>> + * @propname:  The name of the property to set
>>>> + * @len:       The length of the new value of the property
>>>> + * @value:     The new value of the property
>>>> + * @return 0 if successful, -ve on error
>>>> + */
>>>> +int ofnode_set_property(ofnode node, const char *propname, int len,
>>>> +                       const void *value);
>>>
>>> We should think about consistency here. Maybe
>>>
>>> ofnode_write_prop()?
>
> Yes
>
>>>
>>>> +
>>>> +/**
>>>> + * ofnode_write_string() - Set a string property of a ofnode
>>>> + *
>>>> + * @node:      The node for whose string property should be set
>>>> + * @propname:  The name of the string property to set
>>>> + * @value:     The new value of the string property
>>>> + * @return 0 if successful, -ve on error
>>>> + */
>>>> +int ofnode_write_string(ofnode node, const char *propname, const char *value);
>>>> +
>>>> +/**
>>>> + * ofnode_enable() - Enable a device tree node given by its ofnode
>>>> + *
>>>> + * This function effectively sets the node's "status" property to "okay", hence
>>>> + * making it available for driver model initialization.
>>>> + *
>>>> + * @node:      The node to enable
>>>> + * @return 0 if successful, -ve on error
>>>> + */
>>>> +int ofnode_enable(ofnode node);
>>>> +
>>>> +/**
>>>> + * ofnode_disable() - Disable a device tree node given by its ofnode
>>>> + *
>>>> + * This function effectively sets the node's "status" property to "disable",
>>>> + * hence stopping it from being picked up by driver model initialization.
>>>> + *
>>>> + * @node:      The node to disable
>>>> + * @return 0 if successful, -ve on error
>>>> + */
>>>> +int ofnode_disable(ofnode node);
>>>
>>> Would it be OK to have one function like ofnode_set_enabled(ofnode
>>> node, bool enable) ?
>>>
>>> Regards,
>>> Simon
>>
>> Everything else will be addressed in v2. Thanks for reviewing!
>>
>> Best regards,
>>
>> Mario
>
> Regards,
> Simon

Best regards,
Mario