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* [PATCH v6 0/1] Bluetooth: mediatek: add gpio pin to reset bt
@ 2025-07-08  6:01 Zhangchao Zhang
  2025-07-08  6:01 ` [PATCH v6 1/1] " Zhangchao Zhang
  2025-07-08  6:01 ` [PATCH v6] dt-bindings: net: mediatek,mt7925-bluetooth.yaml Zhangchao Zhang
  0 siblings, 2 replies; 10+ messages in thread
From: Zhangchao Zhang @ 2025-07-08  6:01 UTC (permalink / raw)
  To: Marcel Holtmann, Matthias Brugger, Luiz Von Dentz,
	AngeloGioacchino Del Regno, Rob Herring, Krzysztof Kozlowski,
	Conor Dooley
  Cc: Sean Wang, Jiande Lu, Deren Wu, Chris Lu, Hao Qin, Wallace Yu,
	linux-bluetooth, linux-kernel, linux-arm-kernel, linux-mediatek,
	devicetree, Zhangchao Zhang

Reset Bluetooth using hardware pin via dts

Compared with the previously submitted version, the following
information are some specific revision histories

V5-->V6 modifications:
-Add specific revisions in the changes from v4 to v5.
-Add hardware pin title and descriptions to dt-binding submission
   information.
-Modify the title descriptions in the dt-binding file.
-Add 7925 what is it.
-Wrap the descriptions of MT7925 chip uses the USB bus appropriately.
-Change the compatible string to mediatek,mt7925-bluetooth in
   the dt-binding file and driver code.
-Drop gpio-controlelr properties in the dt-binding file.
-Modify the descriptions of the reset-gpios
   properties in the dt-binding file.
-Change the node information of reset-gpios in bluetooth
   from high level valid to low level valid.

V4-->V5 modifications:
-Correct the spelling error of word provides mentioned in V1.
-Drop the xhci0 node and status property in the dt-binding file.
-Modify the bt_reset tag node to bluetooth in the dt-binding file.
-Add #gpio-cell descriptions to properties, nodes and requests.
-Make a separate patch for the changes to dt-binding.

V3-->V4 modifications:
-Modify submission information why use hardware pin to reset Bluetooth.
-Write historical commit information into the cover letter.
-Modify dt binding format information and
   the explanation text in the dt-binding file.

V2-->V3 modifications:
-Changed the capitalization of co-developer names,
   using the correct capitalization of abbreviations and full
   name, and corrected obvious spelling errors.
-Add a revision history.
-Remove the "BT Driver" in the prefix.
-Add the bt-binding document, include inforamtion related to reset
   pin and compatibility matching.
-Add a comment before the schedule_delayed_work function call,
   although schedule_delayed_work is asynchronous, there is no risk.
   Even if it is not completed within 200ms, it will only postpone
   the subsequent probe and will not have any impact.
-Add a comment before the btmtk_reset_by_gpio function call,
   if the compatibility filed or pin cannot be found in the dts
   files, it can still reset bluetooth using software reset.

V2 modifications:
-Modify gpio to GPIO, SW to software,
   and fix other obvious spelling errors.

-- 
2.46.0


^ permalink raw reply	[flat|nested] 10+ messages in thread
* [PATCH v7 1/1] Bluetooth: mediatek: add gpio pin to reset bt
@ 2025-09-05  8:40 Zhangchao Zhang
  2025-09-05  8:59 ` bluez.test.bot
  0 siblings, 1 reply; 10+ messages in thread
From: Zhangchao Zhang @ 2025-09-05  8:40 UTC (permalink / raw)
  To: Marcel Holtmann, Matthias Brugger, Krzysztof Kozlowski,
	Luiz Von Dentz, AngeloGioacchino Del Regno
  Cc: Sean Wang, Jiande Lu, Deren Wu, Chris Lu, Hao Qin,
	linux-bluetooth, linux-kernel, linux-arm-kernel, linux-mediatek,
	Zhangchao Zhang

Makes the platform Bluetooth to be reset by hardware pin,
it provides two methods to do it for mediatek controller,
and it has been tested locally many times and can reset normally.

When an exception occurs, resetting Bluetooth by hardware pin
is more stable than resetting Bluetooth by software.
If the corresponding pin is not found in dts,
bluetooth can also be reset successfully.

Co-developed: Hao Qin <hao.qin@mediatek.com>
Co-developed: Chris Lu <chris.lu@mediatek.com>
Co-developed: Jiande Lu <jiande.lu@mediatek.com>
Signed-off-by: Zhangchao Zhang <ot_zhangchao.zhang@mediatek.com>
---
 drivers/bluetooth/btmtk.c | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/drivers/bluetooth/btmtk.c b/drivers/bluetooth/btmtk.c
index 4390fd571dbd..29d6a93f255d 100644
--- a/drivers/bluetooth/btmtk.c
+++ b/drivers/bluetooth/btmtk.c
@@ -6,6 +6,8 @@
 #include <linux/firmware.h>
 #include <linux/usb.h>
 #include <linux/iopoll.h>
+#include <linux/gpio/consumer.h>
+#include <linux/of.h>
 #include <linux/unaligned.h>
 
 #include <net/bluetooth/bluetooth.h>
@@ -359,11 +361,41 @@ int btmtk_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
 }
 EXPORT_SYMBOL_GPL(btmtk_set_bdaddr);
 
+static int btmtk_hw_gpio_reset(struct hci_dev *hdev, struct btmtk_data *reset_work)
+{
+	struct gpio_desc *reset_gpio;
+
+	/* Find device node*/
+	hdev->dev.of_node = of_find_compatible_node(NULL, NULL, "mediatek,mt7925-bluetooth");
+	reset_gpio = gpiod_get_optional(hdev->dev.of_node, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(reset_gpio))
+		return PTR_ERR(reset_gpio);
+
+	if (!reset_gpio)
+		return -ENODEV;
+
+	if (test_and_set_bit(BTMTK_HW_RESET_ACTIVE, &reset_work->flags)) {
+		bt_dev_err(hdev, "last reset failed? Not resetting again");
+		gpiod_put(reset_gpio);
+		return -EBUSY;
+	}
+	gpiod_set_value_cansleep(reset_gpio, 0);
+	msleep(100);
+	gpiod_set_value_cansleep(reset_gpio, 1);
+	gpiod_put(reset_gpio);
+	return 0;
+}
+
 void btmtk_reset_sync(struct hci_dev *hdev)
 {
 	struct btmtk_data *reset_work = hci_get_priv(hdev);
 	int err;
 
+	/* Try hardware GPIO reset*/
+	err = btmtk_hw_gpio_reset(hdev, reset_work);
+	if (!err)
+		return;
+	/* Otherwise, do software reset */
 	hci_dev_lock(hdev);
 
 	err = hci_cmd_sync_queue(hdev, reset_work->reset_sync, NULL, NULL);
-- 
2.45.2


^ permalink raw reply related	[flat|nested] 10+ messages in thread
* [PATCH v5 1/2] Bluetooth: mediatek: add gpio pin to reset bt
@ 2025-06-27  5:59 Zhangchao Zhang
  2025-06-27  6:42 ` bluez.test.bot
  0 siblings, 1 reply; 10+ messages in thread
From: Zhangchao Zhang @ 2025-06-27  5:59 UTC (permalink / raw)
  To: Marcel Holtmann, Matthias Brugger, Luiz Von Dentz,
	AngeloGioacchino Del Regno, Rob Herring, Krzysztof Kozlowski,
	Conor Dooley
  Cc: Sean Wang, Jiande Lu, Deren Wu, Chris Lu, Hao Qin,
	linux-bluetooth, linux-kernel, linux-arm-kernel, linux-mediatek,
	devicetree, Zhangchao Zhang

Makes the platform Bluetooth to be reset by hardware pin,
it provides two methods to do it for mediatek controller,
and it has been tested locally many times and can reset normally.

When an exception occurs, resetting Bluetooth by hardware pin
is more stable than resetting Bluetooth by software.
If the corresponding pin is not found in dts,
bluetooth can also be reset successfully.

Co-developed: Hao Qin <hao.qin@mediatek.com>
Co-developed: Chris Lu <chris.lu@mediatek.com>
Co-developed: Jiande Lu <jiande.lu@mediatek.com>
Signed-off-by: Zhangchao Zhang <ot_zhangchao.zhang@mediatek.com>
---
 drivers/bluetooth/btmtk.c | 69 +++++++++++++++++++++++++++++++++++++++
 drivers/bluetooth/btmtk.h |  5 +++
 2 files changed, 74 insertions(+)

diff --git a/drivers/bluetooth/btmtk.c b/drivers/bluetooth/btmtk.c
index 4390fd571dbd..4f677f86af1e 100644
--- a/drivers/bluetooth/btmtk.c
+++ b/drivers/bluetooth/btmtk.c
@@ -6,6 +6,8 @@
 #include <linux/firmware.h>
 #include <linux/usb.h>
 #include <linux/iopoll.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
 #include <linux/unaligned.h>
 
 #include <net/bluetooth/bluetooth.h>
@@ -109,6 +111,65 @@ static void btmtk_coredump_notify(struct hci_dev *hdev, int state)
 	}
 }
 
+static void btmtk_reset_by_gpio_work(struct work_struct *work)
+{
+	struct btmtk_reset_gpio *reset_gpio_data =
+			container_of(work, struct btmtk_reset_gpio, reset_work.work);
+
+	gpio_direction_output(reset_gpio_data->gpio_number, 1);
+	kfree(reset_gpio_data);
+}
+
+static int btmtk_reset_by_gpio(struct hci_dev *hdev)
+{
+	struct btmtk_data *data = hci_get_priv(hdev);
+	struct btmtk_reset_gpio *reset_gpio_data;
+	struct device_node *node;
+	int reset_gpio_number;
+
+	node = of_find_compatible_node(NULL, NULL, "mediatek,usb-bluetooth");
+	if (node) {
+		reset_gpio_number = of_get_named_gpio(node, "reset-gpios", 0);
+		if (!gpio_is_valid(reset_gpio_number)) {
+			bt_dev_warn(hdev, "invalid reset GPIO, use software reset");
+			return -EINVAL;
+		}
+	} else {
+		bt_dev_warn(hdev, "no reset GPIO, use software reset");
+		return -ENODEV;
+	}
+
+	/* Toggle the hard reset line. The Mediatek device is going to
+	 * yank itself off the USB and then replug. The cleanup is handled
+	 * correctly on the way out (standard USB disconnect), and the new
+	 * device is detected cleanly and bound to the driver again like
+	 * it should be.
+	 */
+
+	if (test_and_set_bit(BTMTK_HW_RESET_ACTIVE, &data->flags)) {
+		bt_dev_err(hdev, "last reset failed? Not resetting again");
+		return 0;
+	}
+
+	reset_gpio_data = kzalloc(sizeof(*reset_gpio_data), GFP_KERNEL);
+	if (!reset_gpio_data)
+		return -ENOMEM;
+
+	INIT_DELAYED_WORK(&reset_gpio_data->reset_work, btmtk_reset_by_gpio_work);
+	reset_gpio_data->gpio_number = reset_gpio_number;
+
+	gpio_direction_output(reset_gpio_number, 0);
+
+	/* It requires 200ms for mtk bt chip to do reset,
+	 * although Schedule_delayed_work is asynchronous,
+	 * it is risk-free. If it is not completed in 200ms,
+	 * it will only postpone the next probe, which will
+	 * only make the probe run later. There is no other risk.
+	 */
+	schedule_delayed_work(&reset_gpio_data->reset_work, msecs_to_jiffies(200));
+	return 0;
+}
+
 void btmtk_fw_get_filename(char *buf, size_t size, u32 dev_id, u32 fw_ver,
 			   u32 fw_flavor)
 {
@@ -364,6 +425,14 @@ void btmtk_reset_sync(struct hci_dev *hdev)
 	struct btmtk_data *reset_work = hci_get_priv(hdev);
 	int err;
 
+	/* Toggle reset gpio if the platform provides one,
+	 * if the compatibility field or pin cannot be found
+	 * in the dts files, it can still reset bluetooth using
+	 * software reset.
+	 */
+	err = btmtk_reset_by_gpio(hdev);
+	if (!err)
+		return;
 	hci_dev_lock(hdev);
 
 	err = hci_cmd_sync_queue(hdev, reset_work->reset_sync, NULL, NULL);
diff --git a/drivers/bluetooth/btmtk.h b/drivers/bluetooth/btmtk.h
index 5df7c3296624..8a265ce367d1 100644
--- a/drivers/bluetooth/btmtk.h
+++ b/drivers/bluetooth/btmtk.h
@@ -179,6 +179,11 @@ struct btmtk_data {
 	spinlock_t isorxlock;
 };
 
+struct btmtk_reset_gpio {
+	struct delayed_work reset_work;
+	int gpio_number;
+};
+
 typedef int (*wmt_cmd_sync_func_t)(struct hci_dev *,
 				   struct btmtk_hci_wmt_params *);
 
-- 
2.46.0


^ permalink raw reply related	[flat|nested] 10+ messages in thread
* [PATCH v4 1/1] Bluetooth: mediatek: add gpio pin to reset bt
@ 2025-06-23 10:23 Zhangchao Zhang
  2025-06-23 11:06 ` bluez.test.bot
  0 siblings, 1 reply; 10+ messages in thread
From: Zhangchao Zhang @ 2025-06-23 10:23 UTC (permalink / raw)
  To: Marcel Holtmann, Matthias Brugger, Luiz Von Dentz,
	AngeloGioacchino Del Regno
  Cc: Sean Wang, Deren Wu, Chris Lu, Hao Qin, linux-bluetooth,
	linux-kernel, linux-arm-kernel, linux-mediatek, Zhangchao Zhang

Makes the platform Bluetooth to be reset by hardware pin,
it provides two methods to do it for mediatek controller,
and it has been tested locally many times and can reset normally.

When an exception occurs, resetting Bluetooth by hardware pin
is more stable than resetting Bluetooth by software.
If the corresponding pin is not found in dts,
bluetooth can also be reset successfully.

Co-developed: Hao Qin <hao.qin@mediatek.com>
Co-developed: Chris Lu <chris.lu@mediatek.com>
Co-developed: Jiande Lu <jiande.lu@mediatek.com>
Signed-off-by: Zhangchao Zhang <ot_zhangchao.zhang@mediatek.com>
---
 drivers/bluetooth/btmtk.c | 69 +++++++++++++++++++++++++++++++++++++++
 drivers/bluetooth/btmtk.h |  5 +++
 2 files changed, 74 insertions(+)

diff --git a/drivers/bluetooth/btmtk.c b/drivers/bluetooth/btmtk.c
index 4390fd571dbd..3e5f3ca6f0d5 100644
--- a/drivers/bluetooth/btmtk.c
+++ b/drivers/bluetooth/btmtk.c
@@ -6,6 +6,8 @@
 #include <linux/firmware.h>
 #include <linux/usb.h>
 #include <linux/iopoll.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
 #include <linux/unaligned.h>
 
 #include <net/bluetooth/bluetooth.h>
@@ -109,6 +111,65 @@ static void btmtk_coredump_notify(struct hci_dev *hdev, int state)
 	}
 }
 
+static void btmtk_reset_by_gpio_work(struct work_struct *work)
+{
+	struct btmtk_reset_gpio *reset_gpio_data =
+			container_of(work, struct btmtk_reset_gpio, reset_work.work);
+
+	gpio_direction_output(reset_gpio_data->gpio_number, 1);
+	kfree(reset_gpio_data);
+}
+
+static int btmtk_reset_by_gpio(struct hci_dev *hdev)
+{
+	struct btmtk_data *data = hci_get_priv(hdev);
+	struct btmtk_reset_gpio *reset_gpio_data;
+	struct device_node *node;
+	int reset_gpio_number;
+
+	node = of_find_compatible_node(NULL, NULL, "mediatek,usb-bluetooth");
+	if (node) {
+		reset_gpio_number = of_get_named_gpio(node, "reset-gpios", 0);
+		if (!gpio_is_valid(reset_gpio_number)) {
+			bt_dev_warn(hdev, "invalid reset GPIO, use software reset");
+			return -EINVAL;
+		}
+	} else {
+		bt_dev_warn(hdev, "no reset GPIO, use software reset");
+		return -ENODEV;
+	}
+
+	/* Toggle the hard reset line. The Mediatek device is going to
+	 * yank itself off the USB and then replug. The cleanup is handled
+	 * correctly on the way out (standard USB disconnect), and the new
+	 * device is detected cleanly and bound to the driver again like
+	 * it should be.
+	 */
+
+	if (test_and_set_bit(BTMTK_HW_RESET_ACTIVE, &data->flags)) {
+		bt_dev_err(hdev, "last reset failed? Not resetting again");
+		return 0;
+	}
+
+	reset_gpio_data = kzalloc(sizeof(*reset_gpio_data), GFP_KERNEL);
+	if (!reset_gpio_data)
+		return -ENOMEM;
+
+	INIT_DELAYED_WORK(&reset_gpio_data->reset_work, btmtk_reset_by_gpio_work);
+	reset_gpio_data->gpio_number = reset_gpio_number;
+
+	gpio_direction_output(reset_gpio_number, 0);
+
+	/* It requires 200ms for mtk bt chip to do reset,
+	 * although Schedule_delayed_work is asynchronous,
+	 * it is risk-free. If it is not completed in 200ms,
+	 * it will only postpone the next probe, which will
+	 * only make the probe run later. There is no other risk.
+	 */
+	schedule_delayed_work(&reset_gpio_data->reset_work, msecs_to_jiffies(200));
+	return 0;
+}
+
 void btmtk_fw_get_filename(char *buf, size_t size, u32 dev_id, u32 fw_ver,
 			   u32 fw_flavor)
 {
@@ -364,6 +425,14 @@ void btmtk_reset_sync(struct hci_dev *hdev)
 	struct btmtk_data *reset_work = hci_get_priv(hdev);
 	int err;
 
+	/* Toggle reset gpio if the platform provieds one,
+	 * if the compatibility field or pin cannot be found
+	 * in the dts files, it can still reset bluetooth using
+	 * software reset.
+	 */
+	err = btmtk_reset_by_gpio(hdev);
+	if (!err)
+		return;
 	hci_dev_lock(hdev);
 
 	err = hci_cmd_sync_queue(hdev, reset_work->reset_sync, NULL, NULL);
diff --git a/drivers/bluetooth/btmtk.h b/drivers/bluetooth/btmtk.h
index 5df7c3296624..8a265ce367d1 100644
--- a/drivers/bluetooth/btmtk.h
+++ b/drivers/bluetooth/btmtk.h
@@ -179,6 +179,11 @@ struct btmtk_data {
 	spinlock_t isorxlock;
 };
 
+struct btmtk_reset_gpio {
+	struct delayed_work reset_work;
+	int gpio_number;
+};
+
 typedef int (*wmt_cmd_sync_func_t)(struct hci_dev *,
 				   struct btmtk_hci_wmt_params *);
 
-- 
2.46.0


^ permalink raw reply related	[flat|nested] 10+ messages in thread
end of thread, other threads:[~2025-09-05  8:59 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-07-08  6:01 [PATCH v6 0/1] Bluetooth: mediatek: add gpio pin to reset bt Zhangchao Zhang
2025-07-08  6:01 ` [PATCH v6 1/1] " Zhangchao Zhang
2025-07-08  6:07   ` Krzysztof Kozlowski
2025-07-08  6:42   ` bluez.test.bot
2025-07-08  6:01 ` [PATCH v6] dt-bindings: net: mediatek,mt7925-bluetooth.yaml Zhangchao Zhang
2025-07-08  6:05   ` Krzysztof Kozlowski
2025-07-08  6:42   ` [v6] " bluez.test.bot
  -- strict thread matches above, loose matches on Subject: below --
2025-09-05  8:40 [PATCH v7 1/1] Bluetooth: mediatek: add gpio pin to reset bt Zhangchao Zhang
2025-09-05  8:59 ` bluez.test.bot
2025-06-27  5:59 [PATCH v5 1/2] " Zhangchao Zhang
2025-06-27  6:42 ` bluez.test.bot
2025-06-23 10:23 [PATCH v4 1/1] " Zhangchao Zhang
2025-06-23 11:06 ` bluez.test.bot

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