[PATCH] firmware: arm_ffa: Tear down driver during shutdown

The platform core invokes a driver's shutdown callback, rather than its
remove callback, while preparing devices for a normal kexec. Without a
shutdown callback, the FF-A driver leaves notifications, partition devices,
and the RX/TX mapping active before the replacement kernel is booted.

Use ffa_remove() for shutdown so the existing cleanup runs before a normal
kexec and other orderly system shutdowns.

Reported-by: Nat Gurumoorthy <redacted>
Closes: https://lore.kernel.org/all/20260729162731.1383875-1-natg@google.com/
Reported-by: Carol L Soto <redacted>
Closes: https://lore.kernel.org/all/20260818224404.3694580-1-csoto@nvidia.com
Reported-by: Maxi Saparov <redacted>
Closes: https://lore.kernel.org/all/20260826222337.73480-1-maxi.saparov@gmail.com
Signed-off-by: Sudeep Holla <sudeep.holla@kernel.org>
---
  drivers/firmware/arm_ffa/driver.c | 1 +
  1 file changed, 1 insertion(+)

diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c
index 0121bd0a7e01..7f42ffe79f22 100644
--- a/drivers/firmware/arm_ffa/driver.c
+++ b/drivers/firmware/arm_ffa/driver.c

@@ -2271,6 +2271,7 @@ static void ffa_remove(struct platform_device *pdev)
  static struct platform_driver ffa_driver = {
  	.probe = ffa_probe,
  	.remove = ffa_remove,
+	.shutdown = ffa_remove,
  	.driver = {
  		.name = FFA_PLATFORM_NAME,
  	},