[PATCH] mfd: Fix RTS5227 (and others) powermanagement

From: Hans de Goede
Date: Wed Dec 06 2017 - 06:21:45 EST


Commit 8275b77a1513 ("mfd: rts5249: Add support for RTS5250S power
saving") adds powersaving support for device-ids 5249 524a and 525a.

But as a side effect it breaks ASPM support for all the other device-ids,
causing e.g. the Haswell CPU on a Lenovo T440s to not go into a higher
c-state then PC3, while previously it would go to PC7, causing the
machine to idle at 7.4W instead of 6.6W!

The problem here is the new option.dev_aspm_mode field, which only gets
explicitly initialized in the new code for the device-ids 5249 524a and
525a. Leaving the dev_aspm_mode 0 for the other device-ids.

The default dev_aspm_mode 0 is mapped to DEV_ASPM_DISABLE, but the
old behavior of calling rtsx_pci_enable_aspm() when idle and
rtsx_pci_disable_aspm() when busy happens when dev_aspm_mode ==
DEV_ASPM_DYNAMIC.

This commit changes the enum so that 0 = DEV_ASPM_DYNAMIC matching the
old default behavior, fixing the pm regression with the other device-ids.

Cc: Rui Feng <rui_feng@xxxxxxxxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
include/linux/mfd/rtsx_pci.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/mfd/rtsx_pci.h b/include/linux/mfd/rtsx_pci.h
index a2a1318a3d0c..c3d3f04d8cc6 100644
--- a/include/linux/mfd/rtsx_pci.h
+++ b/include/linux/mfd/rtsx_pci.h
@@ -915,10 +915,10 @@ enum PDEV_STAT {PDEV_STAT_IDLE, PDEV_STAT_RUN};
#define LTR_L1SS_PWR_GATE_CHECK_CARD_EN BIT(6)

enum dev_aspm_mode {
- DEV_ASPM_DISABLE = 0,
DEV_ASPM_DYNAMIC,
DEV_ASPM_BACKDOOR,
DEV_ASPM_STATIC,
+ DEV_ASPM_DISABLE,
};

/*
--
2.14.3