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

[AceLan Kao]

From: Hans de Goede <hdegoede at redhat.com>

BugLink: https://bugs.launchpad.net/bugs/1743516

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.

Fixes: 8275b77a1513 ("mfd: rts5249: Add support for RTS5250S power saving")
Signed-off-by: Hans de Goede <hdegoede at redhat.com>
Acked-by: Rui Feng <rui_feng at realsil.com.cn>
Signed-off-by: Lee Jones <lee.jones at linaro.org>
(backported from commit b860b419d970f286294fbfb2b21a4028fd8ee442)
Signed-off-by: AceLan Kao <acelan.kao at canonical.com>
---
 include/linux/rtsx_pci.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/rtsx_pci.h b/include/linux/rtsx_pci.h
index a44670e..478acf6 100644
--- a/include/linux/rtsx_pci.h
+++ b/include/linux/rtsx_pci.h
@@ -1121,10 +1121,10 @@ 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,
 };
 
 /*
-- 
2.7.4