[PATCH v4] PCI: pciehp: Fix the slot in BLINKINGON_STATE when Presence Detect Changed event occurred

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Rongguang Wei <weirongguang@xxxxxxxxxx>

pciehp's behavior is incorrect if the Attention Button is pressed
on an unoccupied slot.

When a Presence Detect Changed event has occurred, the slot status
in either BLINKINGOFF_STATE or OFF_STATE, turn it off unconditionally.
But if the slot status is in BLINKINGON_STATE and the slot is currently
empty, the slot status was staying in BLINKINGON_STATE.

The message print like this:
    pcieport 0000:00:01.5: pciehp: Slot(0-5): Attention button pressed
    pcieport 0000:00:01.5: pciehp: Slot(0-5) Powering on due to button press
    pcieport 0000:00:01.5: pciehp: Slot(0-5): Attention button pressed
    pcieport 0000:00:01.5: pciehp: Slot(0-5): Button cancel
    pcieport 0000:00:01.5: pciehp: Slot(0-5): Action canceled due to button press

It cause the next Attention Button Pressed event become Button cancel
and missing the Presence Detect Changed event with this button press
though this button presses event is occurred after 5s.

According to the Commit d331710ea78f ("PCI: pciehp: Become resilient
to missed events"), if the slot is currently occupied, turn it on and
if the slot is empty, it need to set in OFF_STATE rather than stay in
current status when pciehp_handle_presence_or_link_change() bails out.

V2: Update to simple code and avoid gratuitous message.
V3: Add Suggested-by.
V4: Add state change conditional and message.

Fixes: d331710ea78f ("PCI: pciehp: Become resilient to missed events")
Link: https://lore.kernel.org/linux-pci/20230403054619.19163-1-clementwei90@xxxxxxx/
Link: https://lore.kernel.org/linux-pci/20230421025641.655991-1-clementwei90@xxxxxxx/
Suggested-by: Lukas Wunner <lukas@xxxxxxxxx>
Signed-off-by: Rongguang Wei <weirongguang@xxxxxxxxxx>
---
 drivers/pci/hotplug/pciehp_ctrl.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c
index 529c34808440..32baba1b7f13 100644
--- a/drivers/pci/hotplug/pciehp_ctrl.c
+++ b/drivers/pci/hotplug/pciehp_ctrl.c
@@ -256,6 +256,14 @@ void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events)
 	present = pciehp_card_present(ctrl);
 	link_active = pciehp_check_link_active(ctrl);
 	if (present <= 0 && link_active <= 0) {
+		if (ctrl->state == BLINKINGON_STATE) {
+			ctrl->state = OFF_STATE;
+			cancel_delayed_work(&ctrl->button_work);
+			pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF,
+					      INDICATOR_NOOP);
+			ctrl_info(ctrl, "Slot(%s): Card not present\n",
+				  slot_name(ctrl));
+		}
 		mutex_unlock(&ctrl->state_lock);
 		return;
 	}
-- 
2.25.1


No virus found
		Checked by Hillstone Network AntiVirus




[Index of Archives]     [DMA Engine]     [Linux Coverity]     [Linux USB]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Greybus]

  Powered by Linux