[PATCH v1] Bluetooth: btintel_pcie: fix PM flow for S0ix, S3 and S4

[PATCH v1] Bluetooth: btintel_pcie: fix PM flow for S0ix, S3 and S4

[Ravindra]

Use pm_suspend_target_state to differentiate S0ix from S3/S4. Set the
controller to D3_HOT for S0ix (PM_SUSPEND_TO_IDLE) and D3_COLD for S3/S4
to prevent post-resume instability.

Remove .freeze, .thaw, and .poweroff callbacks to avoid redundant D3
handshakes that time out and abort hibernation. Add .restore to force
FLR-based firmware recovery after S4 and S3 (PM_SUSPEND_MEM), as power
is lost. S0ix resumes via a normal D0 transition.

Fixes: e57362f4911b ("Bluetooth: btintel_pcie: Add support for _suspend() / _resume()")
Assisted-by: GitHub-Copilot:GPT5
Signed-off-by: Ravindra <ravindra@intel.com>
---
 drivers/bluetooth/btintel_pcie.c | 63 ++++++++++++++++----------------
 drivers/bluetooth/btintel_pcie.h |  2 -
 2 files changed, 32 insertions(+), 33 deletions(-)

diff --git a/drivers/bluetooth/btintel_pcie.c b/drivers/bluetooth/btintel_pcie.c
index 005c77a4f5eb..ba5d16a3b3a5 100644
--- a/drivers/bluetooth/btintel_pcie.c
+++ b/drivers/bluetooth/btintel_pcie.c
@@ -16,6 +16,7 @@
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/acpi.h>
+#include <linux/suspend.h>
 
 #include <linux/unaligned.h>
 #include <linux/devcoredump.h>
@@ -3134,11 +3135,14 @@ static void btintel_pcie_coredump(struct device *dev)
 
 static int btintel_pcie_set_dxstate(struct btintel_pcie_data *data, u32 dxstate)
 {
-	int retry = 0, status;
+	int retry = 0;
+	long status;
 	u32 dx_intr_timeout_ms = 200;
 
+	/* Set outside the loop to avoid discarding late interrupts on retry. */
+	data->gp0_received = false;
+
 	do {
-		data->gp0_received = false;
 
 		btintel_pcie_wr_sleep_cntrl(data, dxstate);
 
@@ -3184,18 +3188,20 @@ static int btintel_pcie_suspend_late(struct device *dev, pm_message_t mesg)
 
 	data = pci_get_drvdata(pdev);
 
-	dxstate = (mesg.event == PM_EVENT_SUSPEND ?
+	/* Set D3_HOT for S0ix (s2idle) and D3_COLD for S3 (suspend-to-RAM). */
+	dxstate = (pm_suspend_target_state == PM_SUSPEND_TO_IDLE ?
 		   BTINTEL_PCIE_STATE_D3_HOT : BTINTEL_PCIE_STATE_D3_COLD);
 
-	data->pm_sx_event = mesg.event;
-
 	start = ktime_get();
 
 	/* Refer: 6.4.11.7 -> Platform power management */
 	err = btintel_pcie_set_dxstate(data, dxstate);
 
-	if (err)
+	if (err) {
+		bt_dev_err(data->hdev, "Failed to set dxstate:%u (%d)",
+			   dxstate, err);
 		return err;
+	}
 
 	bt_dev_dbg(data->hdev,
 		   "device entered into d3 state from d0 in %lld us",
@@ -3208,17 +3214,7 @@ static int btintel_pcie_suspend(struct device *dev)
 	return btintel_pcie_suspend_late(dev, PMSG_SUSPEND);
 }
 
-static int btintel_pcie_hibernate(struct device *dev)
-{
-	return btintel_pcie_suspend_late(dev, PMSG_HIBERNATE);
-}
-
-static int btintel_pcie_freeze(struct device *dev)
-{
-	return btintel_pcie_suspend_late(dev, PMSG_FREEZE);
-}
-
-static int btintel_pcie_resume(struct device *dev)
+static int btintel_pcie_resume_event(struct device *dev, pm_message_t mesg)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
 	struct btintel_pcie_data *data;
@@ -3226,19 +3222,15 @@ static int btintel_pcie_resume(struct device *dev)
 	int err;
 
 	data = pci_get_drvdata(pdev);
-	data->gp0_received = false;
 
 	start = ktime_get();
 
-	/* When the system enters S4 (hibernate) mode, bluetooth device loses
-	 * power, which results in the erasure of its loaded firmware.
-	 * Consequently, function level reset (flr) is required on system
-	 * resume to bring the controller back into an operational state by
-	 * initiating a new firmware download.
+	/* S3 and S4 may cut power, erasing the firmware. Force FLR to recover
+	 * instead of a normal D0 transition.
 	 */
-
-	if (data->pm_sx_event == PM_EVENT_FREEZE ||
-	    data->pm_sx_event == PM_EVENT_HIBERNATE) {
+	if (mesg.event == PM_EVENT_RESTORE ||
+	    (mesg.event == PM_EVENT_RESUME &&
+	     pm_suspend_target_state == PM_SUSPEND_MEM)) {
 		set_bit(BTINTEL_PCIE_CORE_HALTED, &data->flags);
 		btintel_pcie_request_reset(data, BTINTEL_PCIE_IOSF_PRR_FLR);
 		return 0;
@@ -3247,7 +3239,9 @@ static int btintel_pcie_resume(struct device *dev)
 	/* Refer: 6.4.11.7 -> Platform power management */
 	err = btintel_pcie_set_dxstate(data, BTINTEL_PCIE_STATE_D0);
 
-	if (err == 0) {
+	if (err) {
+		bt_dev_err(data->hdev, "Failed to set D0 state (%d)", err);
+	} else {
 		bt_dev_dbg(data->hdev,
 			   "device entered into d0 state from d3 in %lld us",
 			   ktime_to_us(ktime_get() - start));
@@ -3272,13 +3266,20 @@ static int btintel_pcie_resume(struct device *dev)
 	return err;
 }
 
+static int btintel_pcie_resume(struct device *dev)
+{
+	return btintel_pcie_resume_event(dev, PMSG_RESUME);
+}
+
+static int btintel_pcie_restore(struct device *dev)
+{
+	return btintel_pcie_resume_event(dev, PMSG_RESTORE);
+}
+
 static const struct dev_pm_ops btintel_pcie_pm_ops = {
 	.suspend = btintel_pcie_suspend,
 	.resume = btintel_pcie_resume,
-	.freeze = btintel_pcie_freeze,
-	.thaw = btintel_pcie_resume,
-	.poweroff = btintel_pcie_hibernate,
-	.restore = btintel_pcie_resume,
+	.restore = btintel_pcie_restore,
 };
 
 static struct pci_driver btintel_pcie_driver = {
diff --git a/drivers/bluetooth/btintel_pcie.h b/drivers/bluetooth/btintel_pcie.h
index 749369b24031..980eb62fdf8b 100644
--- a/drivers/bluetooth/btintel_pcie.h
+++ b/drivers/bluetooth/btintel_pcie.h
@@ -479,7 +479,6 @@ struct btintel_pcie_dump_header {
  * @txq: TX Queue struct
  * @rxq: RX Queue struct
  * @alive_intr_ctxt: Alive interrupt context
- * @pm_sx_event: PM event on which system got suspended
  */
 struct btintel_pcie_data {
 	struct pci_dev	*pdev;
@@ -536,7 +535,6 @@ struct btintel_pcie_data {
 	enum btintel_pcie_reset_type	reset_type;
 	struct btintel_pcie_dbgc	dbgc;
 	struct btintel_pcie_dump_header dmp_hdr;
-	u8	pm_sx_event;
 	u32	debug_evt_addr;
 	u32	debug_evt_size;
 };
-- 
2.43.0

RE: [v1] Bluetooth: btintel_pcie: fix PM flow for S0ix, S3 and S4

[bluez.test.bot]

[-- Attachment #1: Type: text/plain, Size: 566 bytes --]

This is an automated email and please do not reply to this email.

Dear Submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
While preparing the CI tests, the patches you submitted couldn't be applied to the current HEAD of the repository.

----- Output -----

error: patch failed: drivers/bluetooth/btintel_pcie.h:536
error: drivers/bluetooth/btintel_pcie.h: patch does not apply
hint: Use 'git am --show-current-patch' to see the failed patch

Please resolve the issue and submit the patches again.


---
Regards,
Linux Bluetooth