If the platform provides it, use the reset gpio to reset the Intel BT
chip, as part of cmd_timeout handling. This has been found helpful on
Intel bluetooth controllers where the firmware gets stuck and the only
way out is a hard reset pin provided by the platform.
Signed-off-by: Rajat Jain <raja...@google.com>
---
v5: Rename the hook to cmd_timeout, and wait for 5 timeouts before
resetting the device.
v4: Use data->flags instead of clearing the quirk in btusb_hw_reset()
v3: Better error handling for gpiod_get_optional()
v2: Handle the EPROBE_DEFER case.
drivers/bluetooth/btusb.c | 54 +++++++++++++++++++++++++++++++++++++++
1 file changed, 54 insertions(+)
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 4761499db9ee..8949ea30a1bc 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -29,6 +29,7 @@
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/suspend.h>
+#include <linux/gpio/consumer.h>
#include <asm/unaligned.h>
#include <net/bluetooth/bluetooth.h>
@@ -439,6 +440,7 @@ static const struct dmi_system_id
btusb_needs_reset_resume_table[] = {
#define BTUSB_BOOTING 9
#define BTUSB_DIAG_RUNNING 10
#define BTUSB_OOB_WAKE_ENABLED 11
+#define BTUSB_HW_RESET_ACTIVE 12
struct btusb_data {
struct hci_dev *hdev;
@@ -476,6 +478,8 @@ struct btusb_data {
struct usb_endpoint_descriptor *diag_tx_ep;
struct usb_endpoint_descriptor *diag_rx_ep;
+ struct gpio_desc *reset_gpio;
+
__u8 cmdreq_type;
__u8 cmdreq;
@@ -489,8 +493,39 @@ struct btusb_data {
int (*setup_on_usb)(struct hci_dev *hdev);
int oob_wake_irq; /* irq for out-of-band wake-on-bt */
+ unsigned num_cmd_timeout;
};
+
+static void btusb_intel_cmd_timeout(struct hci_dev *hdev,
+ struct hci_command_hdr *cmd)
+{
+ struct btusb_data *data = hci_get_drvdata(hdev);
+ struct gpio_desc *reset_gpio = data->reset_gpio;
+
+ bt_dev_err(hdev, "btusb num_cmd_timeout = %u", ++data->num_cmd_timeout);
+
+ if (data->num_cmd_timeout < 5)
+ return;
+
+ /*
+ * Toggle the hard reset line if the platform provides one. The reset
+ * is going to yank the device off the USB and then replug. So doing
+ * once is enough. 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(BTUSB_HW_RESET_ACTIVE, &data->flags)) {
+ bt_dev_err(hdev, "last reset failed? Not resetting again");
+ return;
+ }
+
+ bt_dev_err(hdev, "Initiating HW reset via gpio");
+ gpiod_set_value(reset_gpio, 1);
+ mdelay(100);
+ gpiod_set_value(reset_gpio, 0);
+}
+
static inline void btusb_free_frags(struct btusb_data *data)
{
unsigned long flags;
@@ -2915,6 +2950,7 @@ static int btusb_probe(struct usb_interface *intf,
const struct usb_device_id *id)
{
struct usb_endpoint_descriptor *ep_desc;
+ struct gpio_desc *reset_gpio;
struct btusb_data *data;
struct hci_dev *hdev;
unsigned ifnum_base;
@@ -3028,6 +3064,15 @@ static int btusb_probe(struct usb_interface *intf,
SET_HCIDEV_DEV(hdev, &intf->dev);
+ reset_gpio = gpiod_get_optional(&data->udev->dev, "reset",
+ GPIOD_OUT_LOW);
+ if (IS_ERR(reset_gpio)) {
+ err = PTR_ERR(reset_gpio);
+ goto out_free_dev;
+ } else if (reset_gpio) {
+ data->reset_gpio = reset_gpio;
+ }
+
hdev->open = btusb_open;
hdev->close = btusb_close;
hdev->flush = btusb_flush;
@@ -3085,6 +3130,8 @@ static int btusb_probe(struct usb_interface *intf,
set_bit(HCI_QUIRK_STRICT_DUPLICATE_FILTER, &hdev->quirks);
set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
set_bit(HCI_QUIRK_NON_PERSISTENT_DIAG, &hdev->quirks);
+ if (data->reset_gpio)
+ hdev->cmd_timeout = btusb_intel_cmd_timeout;
}
if (id->driver_info & BTUSB_INTEL_NEW) {
@@ -3097,6 +3144,8 @@ static int btusb_probe(struct usb_interface *intf,
set_bit(HCI_QUIRK_STRICT_DUPLICATE_FILTER, &hdev->quirks);
set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
set_bit(HCI_QUIRK_NON_PERSISTENT_DIAG, &hdev->quirks);
+ if (data->reset_gpio)
+ hdev->cmd_timeout = btusb_intel_cmd_timeout;
}
if (id->driver_info & BTUSB_MARVELL)
@@ -3226,6 +3275,8 @@ static int btusb_probe(struct usb_interface *intf,
return 0;
out_free_dev:
+ if (data->reset_gpio)
+ gpiod_put(data->reset_gpio);
hci_free_dev(hdev);
return err;
}
@@ -3269,6 +3320,9 @@ static void btusb_disconnect(struct usb_interface *intf)
if (data->oob_wake_irq)
device_init_wakeup(&data->udev->dev, false);
+ if (data->reset_gpio)
+ gpiod_put(data->reset_gpio);
+
hci_free_dev(hdev);
}
--
2.20.1.321.g9e740568ce-goog
