Commit 7602c0ec authored by Konrad Dybcio's avatar Konrad Dybcio Committed by Arnd Bergmann
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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: default avatarKonrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: default avatarSudeep Holla <sudeep.holla@arm.com>
[mani: reworded the description to be more elaborative]
Signed-off-by: default avatarManivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
Tested-by: default avatarJon Hunter <jonathanh@nvidia.com>
Acked-by: default avatarJon Hunter <jonathanh@nvidia.com>
Acked-by: default avatarLorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
parent d1f29ea1

drivers/firmware/psci/psci.c

+10 −0
Original line number Diff line number Diff line
@@ -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)