platform/mellanox: mlxreg-lc: Fix locking issue
Vadim Pasternak authored
Fix locking issues:
- mlxreg_lc_state_update() takes a lock when set or clear
  "MLXREG_LC_POWERED".
- All the devices can be deleted before MLXREG_LC_POWERED flag is cleared.

To fix it:
- Add lock() / unlock() at the beginning / end of
  mlxreg_lc_event_handler() and remove locking from
  mlxreg_lc_power_on_off() and mlxreg_lc_enable_disable()
- Add locked version of mlxreg_lc_state_update() -
  mlxreg_lc_state_update_locked() for using outside
  mlxreg_lc_event_handler().

(2) Remove redundant NULL check for of if 'data->notifier'.

Fixes: 62f9529b

 ("platform/mellanox: mlxreg-lc: Add initial support for Nvidia line card devices")
Reported-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: default avatarVadim Pasternak <vadimp@nvidia.com>
Link: https://lore.kernel.org/r/20220823201937.46855-3-vadimp@nvidia.com

Reviewed-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
1e092b7f
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