Re: [PATCH v2 0/6] use device_for_each_child_node() to access device child nodes

[Lee Jones]

On Sun, 21 Jul 2024, Javier Carrasco wrote:

> This series aims to clarify the use cases of:
> 
> - device_for_each_child_node[_scoped]()
> - fwnode_for_each_available_child_node[_scoped]()
> 
> to access firmware nodes.
> 
> There have been multiple discussions [1][2] about what the first macro
> implies in the sense of availability, and a number of users have opted
> for the second macro in cases where the first one should have been
> preferred.
> 
> The second macro is intended to be used over child nodes of a firmware
> node, not direct child nodes of the device node. Instead, those users
> retrieve the fwnode member from the device struct just to have access to
> a macro that explicitly indicates node availability.
> 
> That workaround is not necessary because `device_for_each_child_node()`
> implies availability for the existing backends (ACPI, DT, swnode).
> 
> This series does not cover other points discussed in [2] like addressing
> uses of `fwnode_for_each_child_node()` where `device_*` should have been
> used, using the `_avaialble_` variant of the fwnode loop whenever
> possible, or adding new `_scoped` macros. Such points will be covered by
> subsequent series to keep focus on the "availability" issue.
> 
> The conversion has been validated with an LTC2992 hwmon sensor, which is
> one of the affected drivers. The rest of the drivers could only be
> compiled and checked with static-analysis tools.
> 
> Link: https://lore.kernel.org/all/20211205190101.26de4a57@jic23-huawei/ [1]
> Link: https://lore.kernel.org/all/20240523-fwnode_for_each_available_child_node_scoped-v2-0-701f3a03f2fb@xxxxxxxxx/ [2]
> 
> Signed-off-by: Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx>
> ---
> Changes in v2:
> - [1/6] property.h: drop "if found" from the description of
>   device_for_each_child_node()
> - [3/6] bd2607mvv.c: fix child node usage.
> - Link to v1: https://lore.kernel.org/r/20240706-device_for_each_child_node-available-v1-0-8a3f7615e41c@xxxxxxxxx
> 
> ---
> Javier Carrasco (6):
>       device property: document device_for_each_child_node macro
>       hwmon: (ltc2992) use device_for_each_child_node_scoped() to access child nodes
>       leds: bd2606mvv: fix device child node usage in bd2606mvv_probe()
>       leds: is31fl319x: use device_for_each_child_node_scoped() to access child nodes
>       leds: pca995x: use device_for_each_child_node() to access device child nodes
>       net: mvpp2: use device_for_each_child_node() to access device child nodes
> 
>  drivers/hwmon/ltc2992.c                         | 19 ++++----------
>  drivers/leds/leds-bd2606mvv.c                   | 23 ++++++++---------
>  drivers/leds/leds-is31fl319x.c                  | 34 ++++++++-----------------
>  drivers/leds/leds-pca995x.c                     | 15 ++++-------
>  drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 13 +++-------
>  include/linux/property.h                        | 10 ++++++++
>  6 files changed, 45 insertions(+), 69 deletions(-)
> ---
> base-commit: 41c196e567fb1ea97f68a2ffb7faab451cd90854
> change-id: 20240701-device_for_each_child_node-available-1c1eca4b6495

fatal: bad object 41c196e567fb1ea97f68a2ffb7faab451cd90854

And the LED patches do not apply to LED.

Please rebase onto -next.

-- 
Lee Jones [李琼斯]