[PATCH 0/2] Bluetooth: btmtksdio: fix MT7663 setup next to the Wi-Fi function

[PATCH 0/2] Bluetooth: btmtksdio: fix MT7663 setup next to the Wi-Fi function

[Ryan Brue]

On MT7663 and MT7668 combo chips the Bluetooth and Wi-Fi SDIO functions
share one ROM patch, and which driver downloads it depends on probe
order. When btmtksdio probes while mt7663s is downloading or starting
its firmware, setup fails, and in the first case the chip is left
unresponsive until reset. Patch 1 waits for the other function's
download to finish; patch 2 retries the function-enable request that
the chip refuses while Wi-Fi is starting.

The matching mt76 fix, for when Bluetooth downloads the patch first, is
posted separately to linux-wireless.

Tested on v7.3 on an Amazon Fire TV Stick (3rd generation, MT8695, with
an MT7663 SDIO module), with both drivers built in: six boots in a row
brought up both functions, with each driver downloading the patch first
at least once, and BLE scanning works next to Wi-Fi.
The patches apply unchanged to bluetooth-next, where they were
build-tested with W=1.

This series was developed with the help of an LLM coding assistant.

Signed-off-by: Ryan Brue <ryanbrue.dev@gmail.com>
---
Ryan Brue (2):
      Bluetooth: btmtksdio: wait while Wi-Fi downloads the shared patch
      Bluetooth: btmtksdio: retry enabling the function on MT7663/MT7668

 drivers/bluetooth/btmtksdio.c | 63 ++++++++++++++++++++++++++++++++++---------
 1 file changed, 51 insertions(+), 12 deletions(-)
---
base-commit: 27731ba091954eccddb2657053b590d2113e8d98
change-id: 20261021-rbrue-sheldon-upstreaming-btmtksdio-mt7663-99d049724644

Best regards,
-- 
Ryan Brue <ryanbrue.dev@gmail.com>

[PATCH 1/2] Bluetooth: btmtksdio: wait while Wi-Fi downloads the shared patch

[Ryan Brue]

On MT7663 and MT7668 the Bluetooth and Wi-Fi SDIO functions share one
ROM patch, guarded by a semaphore in the firmware. The WMT semaphore
query answers 0 while the other function holds the semaphore and is
downloading the patch, 1 when the patch is ready, and 2 when it needs
downloading (MediaTek's own driver: PATCH_IS_DOWNLOAD_BY_OTHER,
PATCH_READY, PATCH_NEED_DOWNLOAD). btmtksdio treated 0 like 1, so when
it probed while mt7663s was downloading, it went on to enable the
Bluetooth function on a half-loaded patch. On an MT7663 module
(Amazon Fire TV Stick) that left the chip unresponsive until reset:

  Bluetooth: hci0: Firmware already downloaded
  Bluetooth: hci0: Execution of wmt command timed out
  mt7663s mmc2:0001:1: Message 00000007 (seq 13) timeout
  mt7663s mmc2:0001:1: Failed to start patch

Map 0 to BTMTK_WMT_PATCH_PROGRESS, and poll every 100 ms, for up to
5 s, while the other function is downloading, as MediaTek's driver
does.

Fixes: 9aebfd4a2200 ("Bluetooth: mediatek: add support for MediaTek MT7663S and MT7668S SDIO devices")
Signed-off-by: Ryan Brue <ryanbrue.dev@gmail.com>
---
 drivers/bluetooth/btmtksdio.c | 35 +++++++++++++++++++++++++++++------
 1 file changed, 29 insertions(+), 6 deletions(-)

diff --git a/drivers/bluetooth/btmtksdio.c b/drivers/bluetooth/btmtksdio.c
index b9563df72983..bb311986271f 100644
--- a/drivers/bluetooth/btmtksdio.c
+++ b/drivers/bluetooth/btmtksdio.c
@@ -234,8 +234,16 @@ static int mtk_hci_wmt_sync(struct hci_dev *hdev,
 
 	switch (wmt_evt->whdr.op) {
 	case BTMTK_WMT_SEMAPHORE:
+		/*
+		 * 0: the other function (Wi-Fi on MT7663/MT7668) holds the
+		 *    semaphore and is downloading the shared patch
+		 * 1: the patch is ready
+		 * 2: the patch needs downloading
+		 */
 		if (wmt_evt->whdr.flag == 2)
 			status = BTMTK_WMT_PATCH_UNDONE;
+		else if (wmt_evt->whdr.flag == 0)
+			status = BTMTK_WMT_PATCH_PROGRESS;
 		else
 			status = BTMTK_WMT_PATCH_DONE;
 		break;
@@ -842,20 +850,35 @@ static int mt76xx_setup(struct hci_dev *hdev, const char *fwname)
 	struct btmtk_hci_wmt_params wmt_params;
 	struct btmtk_tci_sleep tci_sleep;
 	struct sk_buff *skb;
-	int err, status;
+	int err, status, i;
 	u8 param = 0x1;
 
-	/* Query whether the firmware is already download */
+	/*
+	 * Query whether the firmware is already downloaded. While the Wi-Fi
+	 * function downloads the shared patch, wait for it to finish.
+	 */
 	wmt_params.op = BTMTK_WMT_SEMAPHORE;
 	wmt_params.flag = 1;
 	wmt_params.dlen = 0;
 	wmt_params.data = NULL;
 	wmt_params.status = &status;
 
-	err = mtk_hci_wmt_sync(hdev, &wmt_params);
-	if (err < 0) {
-		bt_dev_err(hdev, "Failed to query firmware status (%d)", err);
-		return err;
+	for (i = 0; i < 50; i++) {
+		err = mtk_hci_wmt_sync(hdev, &wmt_params);
+		if (err < 0) {
+			bt_dev_err(hdev, "Failed to query firmware status (%d)",
+				   err);
+			return err;
+		}
+
+		if (status != BTMTK_WMT_PATCH_PROGRESS)
+			break;
+		msleep(100);
+	}
+
+	if (status == BTMTK_WMT_PATCH_PROGRESS) {
+		bt_dev_err(hdev, "Patch download by the other function did not finish");
+		return -EBUSY;
 	}
 
 	if (status == BTMTK_WMT_PATCH_DONE) {

-- 
2.55.0

[PATCH 2/2] Bluetooth: btmtksdio: retry enabling the function on MT7663/MT7668

[Ryan Brue]

Right after the Wi-Fi function of an MT7663 combo chip starts its
firmware, the WMT function-enable request is refused (the reply's flag
byte is 2). btmtksdio ignored the reply, so the following low power
setup command then timed out and setup failed:

  Bluetooth: hci0: command 0xfc7a tx timeout
  Bluetooth: hci0: Failed to apply low power setting (-110)

Check the result and retry every 500 ms, up to ten times, as MediaTek's
own driver retries its power-on command. With mt7663s probing first, the
function now starts on the second attempt and setup completes.

Fixes: 9aebfd4a2200 ("Bluetooth: mediatek: add support for MediaTek MT7663S and MT7668S SDIO devices")
Signed-off-by: Ryan Brue <ryanbrue.dev@gmail.com>
---
 drivers/bluetooth/btmtksdio.c | 28 ++++++++++++++++++++++------
 1 file changed, 22 insertions(+), 6 deletions(-)

diff --git a/drivers/bluetooth/btmtksdio.c b/drivers/bluetooth/btmtksdio.c
index bb311986271f..239393a15e46 100644
--- a/drivers/bluetooth/btmtksdio.c
+++ b/drivers/bluetooth/btmtksdio.c
@@ -909,17 +909,33 @@ static int mt76xx_setup(struct hci_dev *hdev, const char *fwname)
 		goto ignore_func_on;
 	}
 
-	/* Enable Bluetooth protocol */
+	/*
+	 * Enable Bluetooth protocol. While the Wi-Fi function of a combo
+	 * chip is still starting its firmware, the request is refused, so
+	 * retry it.
+	 */
 	wmt_params.op = BTMTK_WMT_FUNC_CTRL;
 	wmt_params.flag = 0;
 	wmt_params.dlen = sizeof(param);
 	wmt_params.data = &param;
-	wmt_params.status = NULL;
+	wmt_params.status = &status;
 
-	err = mtk_hci_wmt_sync(hdev, &wmt_params);
-	if (err < 0) {
-		bt_dev_err(hdev, "Failed to send wmt func ctrl (%d)", err);
-		return err;
+	for (i = 0; i < 10; i++) {
+		err = mtk_hci_wmt_sync(hdev, &wmt_params);
+		if (err < 0) {
+			bt_dev_err(hdev, "Failed to send wmt func ctrl (%d)",
+				   err);
+			return err;
+		}
+
+		if (status == BTMTK_WMT_ON_DONE)
+			break;
+		msleep(500);
+	}
+
+	if (status != BTMTK_WMT_ON_DONE) {
+		bt_dev_err(hdev, "Bluetooth function refused to start");
+		return -EIO;
 	}
 
 	set_bit(BTMTKSDIO_PATCH_ENABLED, &bdev->tx_state);

-- 
2.55.0

RE: Bluetooth: btmtksdio: fix MT7663 setup next to the Wi-Fi function

[bluez.test.bot]

[-- Attachment #1: Type: text/plain, Size: 1020 bytes --]

This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/series/1194005/

---Test result---

Test Summary:
CheckPatch                    PASS      1.41 seconds
VerifyFixes                   PASS      0.07 seconds
VerifySignedoff               PASS      0.10 seconds
GitLint                       PASS      0.41 seconds
SubjectPrefix                 PASS      0.12 seconds
BuildKernel                   PASS      28.70 seconds
CheckAllWarning               PASS      32.82 seconds
CheckSparse                   PASS      35.66 seconds
BuildKernel32                 PASS      28.78 seconds
CheckKernelLLVM               PASS      34.29 seconds
TestRunnerSetup               PASS      684.87 seconds
IncrementalBuild              PASS      29.06 seconds



https://github.com/bluez/bluetooth-next/pull/1003

---
Regards,
Linux Bluetooth