diff mbox series

[v5,2/2] Bluetooth: hci_h5: Add power reset via gpio in h5_btrtl_open

Message ID 20220125161401.729179-3-adeep@lexina.in
State Accepted
Commit adce573b927adf827f2f8627f05c2ba90031ebc9
Headers show
Series Bluetooth: hci_h5: btrtl: Add support for RTL8822CS hci_ver 0x08 | expand

Commit Message

Viacheslav Jan. 25, 2022, 4:14 p.m. UTC
Add power reset for bluetooth via enable-gpios in h5_btrtl_open function.

Signed-off-by: Vyacheslav Bocharov <adeep@lexina.in>
---

While testing the RTL8822CS SDIO WiFi/BT adapter, I found that in some
cases the kernel could not initialize it. However, manually resetting the
adapter via gpio allows it to start correctly.
Apparently at system start the adapter is in an undefined state (including
the unknown state of gpio after starting uboot). A forced reset helps to
initialize the adapter in most cases. Experimentally it was found that
100ms is enough to reset.

 drivers/bluetooth/hci_h5.c | 5 +++++
 1 file changed, 5 insertions(+)

Comments

Marcel Holtmann Jan. 25, 2022, 9:42 p.m. UTC | #1
Hi Vyachselav,

> Add power reset for bluetooth via enable-gpios in h5_btrtl_open function.
> 
> Signed-off-by: Vyacheslav Bocharov <adeep@lexina.in>
> ---
> 
> While testing the RTL8822CS SDIO WiFi/BT adapter, I found that in some
> cases the kernel could not initialize it. However, manually resetting the
> adapter via gpio allows it to start correctly.
> Apparently at system start the adapter is in an undefined state (including
> the unknown state of gpio after starting uboot). A forced reset helps to
> initialize the adapter in most cases. Experimentally it was found that
> 100ms is enough to reset.

if you put this here, then this information is lost. So move it to the commit message.

Regards

Marcel
diff mbox series

Patch

diff --git a/drivers/bluetooth/hci_h5.c b/drivers/bluetooth/hci_h5.c
index 34286ffe0568..fdf504b0d265 100644
--- a/drivers/bluetooth/hci_h5.c
+++ b/drivers/bluetooth/hci_h5.c
@@ -966,6 +966,11 @@  static void h5_btrtl_open(struct h5 *h5)
 		pm_runtime_enable(&h5->hu->serdev->dev);
 	}
 
+	/* The controller needs reset to startup */
+	gpiod_set_value_cansleep(h5->enable_gpio, 0);
+	gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
+	msleep(100);
+
 	/* The controller needs up to 500ms to wakeup */
 	gpiod_set_value_cansleep(h5->enable_gpio, 1);
 	gpiod_set_value_cansleep(h5->device_wake_gpio, 1);