usb: typec: Implement UCSI driver for ChromeOS

This series implements a UCSI ChromeOS EC transport driver. 
The ChromeOS EC is expected to implement UCSI Platform Policy
Manager (PPM).

---
Changes in v8:
- Set .sync_control in cros_ucsi_ops struct to point
to ucsi_sync_control_common().
- Added explanation why complete() is used instead of resume()
in cros_ucsi_pm_ops struct.
- Updated s/miliseconds/milliseconds/.
- Link to v7: https://lore.kernel.org/linux-usb/20241115155234.1587589-... 

Changes in v7:
- Dropped the following commits for now as I want to focus
on upstreaming cros_ec_ucsi driver first. Then I will get
back to the topic of trace events and netlink:
  "usb: typec: cros_ec_ucsi: Add trace events"
  "usb: typec: cros_ec_ucsi: Add netlink"
- Squashed "usb: typec: cros_ec_ucsi: Use complete instead of resume"
into "usb: typec: ucsi: Implement ChromeOS UCSI driver".
- Added "usb: typec: cros_ec_ucsi: Recover from write timeouts" commmit.
- Added usage of common functins ucsi_sync_control_common()
and ucsi_notify_common().
- Commits:
  "platform/chrome: Update EC feature flags"
  "mfd: cros_ec: Load cros_ec_ucsi on supported ECs"
  "mfd: cros_ec: Don't load charger with UCSI"
landed in the tree https://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd.g...    
- Link to v6: https://lore.kernel.org/linux-usb/20240910101527.603452-1...

Changes in v6:
- Reverted to type names uint*_t in cros_ec_commands.h in order 
to be consistent with type names used in other parts of the file.
- Updated comments in cros_ec_commands.h related to UCSI.
- Added missing sign-offs.
- Fixed memory leak in cros_ucsi_async_control() by moving
ec_params_ucsi_ppm_set request buffer to stack.
- Replaced cros_ucsi_read with cros_ucsi_read_cci in cros_ucsi_work().
- Updated changes in v5, it was missing information related to
commits addition:
  platform/chrome: Update EC feature flags
  usb: typec: cros_ec_ucsi: Use complete instead of resume
  mfd: cros_ec: Load cros_ec_ucsi on supported ECs
  mfd: cros_ec: Don't load charger with UCSI
- Link to v5: https://lore.kernel.org/r/all/20240903163033.3170815-1-uk...

Changes in v5:
- Increased WRITE_TMO_MS to 5000.
- Replaced DRV_NAME with KBUILD_MODNAME.
- Added comments for WRITE_TMO_MS and MAX_EC_DATA_SIZE defines.
- Refactored cros_ucsi_async_control() to dynamically allocate memory
for a message to EC instead of allocating the message on stack.
- Replaced type names uint*_t with u*.
- Removed ret variable in cros_ucsi_work().
- Updated ucsi_operations interface to align with changes introduced in
  v6.11.
- Replaced test_bit() with test_and_clear_bit() in cros_ucsi_work().
- Updated EC feature flags in commit "platform/chrome: Update EC feature
  flags".
- Added new commit "usb: typec: cros_ec_ucsi: Use complete instead
of resume".
- Added trace events in commit "usb: typec: cros_ec_ucsi: Add trace
  events".
- Added netlink in commit "usb: typec: cros_ec_ucsi: Add netlink"
for debugging and testing puropses.
- Added new commit "mfd: cros_ec: Load cros_ec_ucsi on supported ECs".
- Added new commit "mfd: cros_ec: Don't load charger with UCSI".
- Link to v4: https://lore.kernel.org/all/CAB2FV=6We88NrvN8NZYt8NkMFH9N...

Changes in v4:
- Setup notifications before calling ucsi_register.
- Cancel work before destroying driver data.
- Link to v3: https://lore.kernel.org/r/20240403-public-ucsi-h-v3-0-f84...

Changes in v3:
- Moved driver from platform/chrome to usb/typec/ucsi.
- Used id_table instead of MODULE_ALIAS.
- Split EC header changes into seperate commit.
- Fixes from additional internal reviews and kernel bot warnings.
- Link to v2: https://lore.kernel.org/r/20240325-public-ucsi-h-v2-0-a6d...

Changes in v2:
- No code or commit message changes.
- Added drivers/platform/chrome maintainers for review.

Abhishek Pandit-Subedi (1):
  usb: typec: cros_ec_ucsi: Recover from write timeouts

Pavan Holla (2):
  platform/chrome: Update ChromeOS EC header for UCSI
  usb: typec: ucsi: Implement ChromeOS UCSI driver

 MAINTAINERS                                   |   7 +
 drivers/usb/typec/ucsi/Kconfig                |  13 +
 drivers/usb/typec/ucsi/Makefile               |   1 +
 drivers/usb/typec/ucsi/cros_ec_ucsi.c         | 338 ++++++++++++++++++
 .../linux/platform_data/cros_ec_commands.h    |  28 +-
 5 files changed, 386 insertions(+), 1 deletion(-)
 create mode 100644 drivers/usb/typec/ucsi/cros_ec_ucsi.c

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2.47.0.338.g60cca15819-goog