[PATCH] wifi: ath11k: Add a warning for wcn6855 spurious wakeup events

[Mario Limonciello]

When WCN6855 firmware versions less than 0x110B196E are used with
an AMD APU and the user puts the system into s2idle spurious wakeup
events can occur. These are difficult to attribute to the WLAN F/W
so add a warning to the kernel driver to give users a hint where
to look.

This was tested on WCN6855 and a Lenovo Z13 with the following
firmware versions:
WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.9
WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.23

Link: http://lists.infradead.org/pipermail/ath11k/2023-February/004024.html
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2377
Link: https://bugs.launchpad.net/ubuntu/+source/linux-firmware/+bug/2006458
Link: https://lore.kernel.org/linux-gpio/20221012221028.4817-1-mario.limonciello@xxxxxxx/
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
 drivers/net/wireless/ath/ath11k/pci.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/net/wireless/ath/ath11k/pci.c b/drivers/net/wireless/ath/ath11k/pci.c
index 99cf3357c66e..87536327e214 100644
--- a/drivers/net/wireless/ath/ath11k/pci.c
+++ b/drivers/net/wireless/ath/ath11k/pci.c
@@ -8,6 +8,7 @@
 #include <linux/msi.h>
 #include <linux/pci.h>
 #include <linux/of.h>
+#include <linux/suspend.h>
 
 #include "pci.h"
 #include "core.h"
@@ -27,6 +28,8 @@
 #define QCN9074_DEVICE_ID		0x1104
 #define WCN6855_DEVICE_ID		0x1103
 
+#define WCN6855_S2IDLE_VER		0x110b196e
+
 static const struct pci_device_id ath11k_pci_id_table[] = {
 	{ PCI_VDEVICE(QCOM, QCA6390_DEVICE_ID) },
 	{ PCI_VDEVICE(QCOM, WCN6855_DEVICE_ID) },
@@ -965,6 +968,27 @@ static void ath11k_pci_shutdown(struct pci_dev *pdev)
 	ath11k_pci_power_down(ab);
 }
 
+static void ath11k_check_s2idle_bug(struct ath11k_base *ab)
+{
+	struct pci_dev *rdev;
+
+	if (pm_suspend_target_state != PM_SUSPEND_TO_IDLE)
+		return;
+
+	if (ab->id.device != WCN6855_DEVICE_ID)
+		return;
+
+	if (ab->qmi.target.fw_version >= WCN6855_S2IDLE_VER)
+		return;
+
+	rdev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0, 0));
+	if (rdev->vendor == PCI_VENDOR_ID_AMD)
+		ath11k_warn(ab, "fw_version 0x%x may cause spurious wakeups. Upgrade to 0x%x or later.",
+			    ab->qmi.target.fw_version, WCN6855_S2IDLE_VER);
+
+	pci_dev_put(rdev);
+}
+
 static __maybe_unused int ath11k_pci_pm_suspend(struct device *dev)
 {
 	struct ath11k_base *ab = dev_get_drvdata(dev);
@@ -975,6 +999,8 @@ static __maybe_unused int ath11k_pci_pm_suspend(struct device *dev)
 		return 0;
 	}
 
+	ath11k_check_s2idle_bug(ab);
+
 	ret = ath11k_core_suspend(ab);
 	if (ret)
 		ath11k_warn(ab, "failed to suspend core: %d\n", ret);
-- 
2.34.1