From 7602c0ec0bbfd3985d49f4f0cad281c1414008c9 Mon Sep 17 00:00:00 2001 From: Konrad Dybcio Date: Wed, 31 Dec 2025 21:51:26 +0530 Subject: [PATCH] firmware: psci: Set pm_set_resume/suspend_via_firmware() for SYSTEM_SUSPEND PSCI specification defines the SYSTEM_SUSPEND feature which enables the firmware to implement the suspend to RAM (S2RAM) functionality by transitioning the system to a deeper low power state. When the system enters such state, the power to the peripheral devices might be removed. So the respective device drivers must prepare for the possible removal of the power by performing actions such as shutting down or resetting the device in their system suspend callbacks. The Linux PM framework allows the platform drivers to convey this info to device drivers by calling the pm_set_suspend_via_firmware() and pm_set_resume_via_firmware() APIs. Hence, if the PSCI firmware supports SYSTEM_SUSPEND feature, call the above mentioned APIs in the psci_system_suspend_begin() and psci_system_suspend_enter() callbacks. Signed-off-by: Konrad Dybcio Reviewed-by: Sudeep Holla [mani: reworded the description to be more elaborative] Signed-off-by: Manivannan Sadhasivam Tested-by: Jon Hunter Acked-by: Jon Hunter Acked-by: Lorenzo Pieralisi Signed-off-by: Arnd Bergmann --- drivers/firmware/psci/psci.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c index 38ca190d4a22..e73bae6cb23a 100644 --- a/drivers/firmware/psci/psci.c +++ b/drivers/firmware/psci/psci.c @@ -539,12 +539,22 @@ static int psci_system_suspend(unsigned long unused) static int psci_system_suspend_enter(suspend_state_t state) { + pm_set_resume_via_firmware(); + return cpu_suspend(0, psci_system_suspend); } +static int psci_system_suspend_begin(suspend_state_t state) +{ + pm_set_suspend_via_firmware(); + + return 0; +} + static const struct platform_suspend_ops psci_suspend_ops = { .valid = suspend_valid_only_mem, .enter = psci_system_suspend_enter, + .begin = psci_system_suspend_begin, }; static void __init psci_init_system_reset2(void)