On 1/25/22 11:53 AM, Sean Anderson wrote:
> Hi Heikki,
>
> On 1/25/22 4:18 AM, Heikki Krogerus wrote:
>> On Mon, Jan 24, 2022 at 12:33:44PM -0500, Sean Anderson wrote:
>>> of_node_put should always be called on device nodes gotten from
>>> of_get_*. Additionally, it should only be called after there are no
>>> remaining users. To address the first issue, call of_node_put if later
>>> steps in ulpi_register fail. To address the latter, call of_node_put
>>> only after calling device_unregister.
>>
>> This looks like a fix, but you don't have the fix tag.
>
> You're right this should have
>
> Fixes: ef6a7bcfb01c ("usb: ulpi: Support device discovery via DT")
>
>>> Signed-off-by: Sean Anderson <sean.anderson@xxxxxxxx>
>>> ---
>>>
>>> Changes in v2:
>>> - New
>>>
>>> drivers/usb/common/ulpi.c | 10 +++++++---
>>> 1 file changed, 7 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/usb/common/ulpi.c b/drivers/usb/common/ulpi.c
>>> index 87deb514eb78..c6ba72544f2b 100644
>>> --- a/drivers/usb/common/ulpi.c
>>> +++ b/drivers/usb/common/ulpi.c
>>> @@ -301,11 +301,11 @@ static int ulpi_register(struct device *dev, struct ulpi *ulpi)
>>>
>>> ret = ulpi_read_id(ulpi);
>>> if (ret)
>>> - return ret;
>>> + goto err;
>>>
>>> ret = device_register(&ulpi->dev);
>>> if (ret)
>>> - return ret;
>>> + goto err;
>>
>> I think there is another bug in the code here. Missing put_device().
>
> So what is the correct way to create a device? Shouldn't device_register
> be paired with device_unregister? And from what I can tell,
> device_unregister does not put the of_node.
>
>> If you first fix that, you should then be able to call
>> fwnode_handle_put() (instead of of_node_put())
>
> Well, we currently only have a ulpi_of_register, so I don't think we
> will have a fwnode here. But I can use that if you wish.
Hm, looks like I missed the ACPI_COMPANION_SET
So this should probably be fwnode_handle_put.
But ACPI_COMPANION_SET doesn't seem to get the fwnode?
> --Sean
>
>> from
>> ulpi_dev_release(), and that should cover all cases.
>>
>>> root = debugfs_create_dir(dev_name(dev), ULPI_ROOT);
>>> debugfs_create_file("regs", 0444, root, ulpi, &ulpi_regs_ops);
>>> @@ -314,6 +314,10 @@ static int ulpi_register(struct device *dev, struct ulpi *ulpi)
>>> ulpi->id.vendor, ulpi->id.product);
>>>
>>> return 0;
>>> +
>>> +err:
>>> + of_node_put(ulpi->dev.of_node);
>>> + return ret;
>>
>> So no need for that.
>>
>>> }
>>>
>>> /**
>>> @@ -357,8 +361,8 @@ void ulpi_unregister_interface(struct ulpi *ulpi)
>>> {
>>> debugfs_remove_recursive(debugfs_lookup(dev_name(&ulpi->dev),
>>> ULPI_ROOT));
>>> - of_node_put(ulpi->dev.of_node);
>>> device_unregister(&ulpi->dev);
>>> + of_node_put(ulpi->dev.of_node);
>>> }
>>
>> And here you can just remove that of_node_put() call.
>>
>> thanks,
>>
>
