On Tue, Nov 06, 2018 at 05:35:25PM +0530, Balakrishna Godavarthi wrote:
> wcn3990 requires a power pulse to turn ON/OFF along with
> regulators. Sometimes we are observing the power pulses are sent
> out with some time delay, due to queuing these commands. This is
> causing synchronization issues with chip, which intern delay the
> chip setup or may end up with communication issues.
>
> Signed-off-by: Balakrishna Godavarthi <bgodavar@xxxxxxxxxxxxxx>
> ---
> drivers/bluetooth/hci_qca.c | 22 +++++++++-------------
> 1 file changed, 9 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
> index f72ded4ec9ae..051f081d1835 100644
> --- a/drivers/bluetooth/hci_qca.c
> +++ b/drivers/bluetooth/hci_qca.c
> @@ -1016,8 +1016,7 @@ static inline void host_set_baudrate(struct hci_uart *hu, unsigned int speed)
> static int qca_send_power_pulse(struct hci_dev *hdev, u8 cmd)
> {
> struct hci_uart *hu = hci_get_drvdata(hdev);
> - struct qca_data *qca = hu->priv;
> - struct sk_buff *skb;
> + int ret;
>
> /* These power pulses are single byte command which are sent
> * at required baudrate to wcn3990. On wcn3990, we have an external
> @@ -1030,18 +1029,14 @@ static int qca_send_power_pulse(struct hci_dev *hdev, u8 cmd)
> * sending power pulses to SoC.
> */
> bt_dev_dbg(hdev, "sending power pulse %02x to SoC", cmd);
> -
> - skb = bt_skb_alloc(sizeof(cmd), GFP_KERNEL);
> - if (!skb)
> - return -ENOMEM;
> -
> hci_uart_set_flow_control(hu, true);
> + ret = serdev_device_write(hu->serdev, &cmd, sizeof(cmd), 0);
Don't you want a non-zero timeout here? Otherwise you might as well call
serdev_device_write() directly.
Also have you made sure that serdev_device_write_wakeup() is called in
the drivers write-wakeup callback as serdev_device_write() requires?
See this series in case what you really wanted was to wait indefinitely
(you can use MAX_SCHEDULE_TIMEOUT):
https://lkml.kernel.org/r/<20181114150904.19653-1-johan@xxxxxxxxxx>
> + if (ret < 0) {
> + bt_dev_err(hdev, "failed to send power pulse %02x to SoC", cmd);
> + return ret;
> + }
>
> - skb_put_u8(skb, cmd);
> - hci_skb_pkt_type(skb) = HCI_COMMAND_PKT;
> -
> - skb_queue_tail(&qca->txq, skb);
> - hci_uart_tx_wakeup(hu);
> + serdev_device_wait_until_sent(hu->serdev, 0);
>
> /* Wait for 100 uS for SoC to settle down */
> usleep_range(100, 200);
> @@ -1283,7 +1278,8 @@ static void qca_power_shutdown(struct hci_uart *hu)
>
> host_set_baudrate(hu, 2400);
> hci_uart_set_flow_control(hu, true);
> - serdev_device_write_buf(serdev, &cmd, sizeof(cmd));
> + serdev_device_write(serdev, &cmd, sizeof(cmd), 0);
Same here.
> + serdev_device_wait_until_sent(serdev, 0);
> hci_uart_set_flow_control(hu, false);
> qca_power_setup(hu, false);
> }
Johan
