[PATCH v2 3/3] Bluetooth: hci_qca: Add delay after power-off pulse

From: Matthias Kaehlcke
Date: Tue Feb 26 2019 - 14:47:17 EST


During initialization the power-on pulse is currently sent inmediately
after the prior power-off pulse. With this initialization often fails
at boot time:

[ 15.205224] Bluetooth: hci0: setting up wcn3990
[ 17.341062] Bluetooth: hci0: command 0xfc00 tx timeout
[ 22.101453] ERROR: Bluetooth initialization failed
[ 25.337740] Bluetooth: hci0: Reading QCA version information failed (-110)

After a power-off pulse wait 10ms to give the controller time to power
off. Remove the previous short settling delay, it isn't needed anymore.

Signed-off-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
Reviewed-by: Balakrishna Godavarthi <bgodavar@xxxxxxxxxxxxxx>
---
Changes in v2:
- removed previous short setting delay
- updated commit message
- added 'Reviewed-by: Balakrishna Godavarthi <bgodavar@xxxxxxxxxxxxxx>' tag
---
drivers/bluetooth/hci_qca.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
index eacc108c422d0..3f77140798dd1 100644
--- a/drivers/bluetooth/hci_qca.c
+++ b/drivers/bluetooth/hci_qca.c
@@ -1031,13 +1031,13 @@ static int qca_send_power_pulse(struct hci_uart *hu, bool on)
}

serdev_device_wait_until_sent(hu->serdev, timeout);
-
- /* Wait for 100 uS for SoC to settle down */
- usleep_range(100, 200);
hci_uart_set_flow_control(hu, false);

+ /* Give to controller time to boot/shutdown */
if (on)
msleep(100);
+ else
+ msleep(10);

return 0;
}
--
2.21.0.rc2.261.ga7da99ff1b-goog