On 12/3/2024 8:33 AM, Zijun Hu wrote:

This patch series is to constify the following API:
struct device *device_find_child(struct device *dev, void *data,
		int (*match)(struct device *dev, void *data));
To :
struct device *device_find_child(struct device *dev, const void *data,
				 device_match_t match);
typedef int (*device_match_t)(struct device *dev, const void *data);

Why to constify the API?

- Protect caller's match data @*data which is for comparison and lookup
  and the API does not actually need to modify @*data.

- Make the API's parameters (@match)() and @data have the same type as
  all of other device finding APIs (bus|class|driver)_find_device().

- All kinds of existing device matching functions can be directly taken
  as the API's argument, they were exported by driver core.

How to constify the API?

- Now, no (@match)() argument of the API usages is modifying its match
  data @*data after previous cleanup, so it is easy and safe to make its
  parameter @data take const void * as type.

- Simplify involved codes further if it is possbile with benefits
  brought by constifying the API.

Signed-off-by: Zijun Hu <redacted>
---
Changes in v2:
- Series v1 have no code review comments and are posted a long time ago, so may ignore differences.
- Link to v1: https://lore.kernel.org/r/20240811-const_dfc_done-
v1-0-9d85e3f943cb@quicinc.com
- Motivation link: https://lore.kernel.org/lkml/917359cc-a421-41dd-93f4-d28937fe2325@icloud.com (local)

---
Zijun Hu (32):
      driver core: Constify API device_find_child()
      driver core: Introduce device_match_type() to match device with a device type
      drm/mediatek: Adapt for constified device_find_child()
      hwmon: Adapt for constified device_find_child()
      media: pci: mgb4: Adapt for constified device_find_child()
      thunderbolt: Adapt for constified device_find_child()
      gpio: sim: Remove gpio_sim_dev_match_fwnode()
      net: dsa: Adapt for constified device_find_child()
      pwm: Adapt for constified device_find_child()
      nvdimm: Adapt for constified device_find_child()
      libnvdimm: Simplify nd_namespace_store() implementation
      firewire: core: Adapt for constified device_find_child()
      serial: core: Adapt for constified device_find_child()
      usb: typec: class: Remove both cable_match() and partner_match()
      usb: typec: class: Adapt for constified device_find_child()
      slimbus: core: Simplify of_find_slim_device() implementation
      slimbus: core: Constify slim_eaddr_equal()
      slimbus: core: Adapt for constified device_find_child()
      scsi: iscsi: Constify API iscsi_find_flashnode_sess()
      scsi: qla4xxx: Adapt for constified iscsi_find_flashnode_sess()
      scsi: iscsi: Adapt for constified device_find_child()
      cxl/region: Adapt for constified device_find_child()
      cxl/pmem: Remove match_nvdimm_bridge()
      cxl/core/pci: Adapt for constified device_find_child()
      cxl/test: Adapt for constified device_find_child()
      sparc: vio: Adapt for constified device_find_child()
      bus: fsl-mc: Adapt for constified device_find_child()
      block: sunvdc: Adapt for constified device_find_child()
      firmware: arm_scmi: Adapt for constified device_find_child()
      efi: dev-path-parser: Adapt for constified device_find_child()
      rpmsg: core: Adapt for constified device_find_child()
      driver core: Simplify API device_find_child_by_name() implementation

sorry for that only part of this series [0/32, 11/32] were sent out due
to mail account capability limitation.

will solve the limitation and send out whole patch series as v3.

thanks (^^)