/* Reset device */
static int hci_uart_flush(struct hci_dev *hdev)
{
struct hci_uart *hu = hci_get_drvdata(hdev);
BT_DBG("hdev %p serdev %p", hdev, hu->serdev);
if (hu->tx_skb) {
kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
}
/* Flush any pending characters in the driver and discipline. */
serdev_device_write_flush(hu->serdev);
if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
hu->proto->flush(hu);
return 0;
}
static int nokia_reset(struct hci_uart *hu)
{
struct nokia_bt_dev *btdev = hu->priv;
struct device *dev = &btdev->serdev->dev;
int err;
/* reset routine */
gpiod_set_value_cansleep(btdev->reset, 1);
gpiod_set_value_cansleep(btdev->wakeup_bt, 1);
msleep(100);
/* safety check */
err = gpiod_get_value_cansleep(btdev->wakeup_host);
if (err == 1) {
dev_err(dev, "reset: host wakeup not low!");
return -EPROTO;
}
/* flush queue */
serdev_device_write_flush(btdev->serdev);
/* init uart */
nokia_flow_control(btdev->serdev, false);
serdev_device_set_baudrate(btdev->serdev, INIT_BAUD_RATE);
gpiod_set_value_cansleep(btdev->reset, 0);
/* wait for cts */
err = serdev_device_wait_for_cts(btdev->serdev, true, 200);
if (err < 0) {
dev_err(dev, "CTS not received: %d", err);
return err;
}
nokia_flow_control(btdev->serdev, true);
return 0;
}
static int qca_send_power_pulse(struct hci_uart *hu, bool on)
{
int ret;
int timeout = msecs_to_jiffies(CMD_TRANS_TIMEOUT_MS);
u8 cmd = on ? QCA_WCN3990_POWERON_PULSE : QCA_WCN3990_POWEROFF_PULSE;
/* These power pulses are single byte command which are sent
* at required baudrate to wcn3990. On wcn3990, we have an external
* circuit at Tx pin which decodes the pulse sent at specific baudrate.
* For example, wcn3990 supports RF COEX antenna for both Wi-Fi/BT
* and also we use the same power inputs to turn on and off for
* Wi-Fi/BT. Powering up the power sources will not enable BT, until
* we send a power on pulse at 115200 bps. This algorithm will help to
* save power. Disabling hardware flow control is mandatory while
* sending power pulses to SoC.
*/
bt_dev_dbg(hu->hdev, "sending power pulse %02x to controller", cmd);
serdev_device_write_flush(hu->serdev);
hci_uart_set_flow_control(hu, true);
ret = serdev_device_write_buf(hu->serdev, &cmd, sizeof(cmd));
if (ret < 0) {
bt_dev_err(hu->hdev, "failed to send power pulse %02x", cmd);
return ret;
}
serdev_device_wait_until_sent(hu->serdev, timeout);
hci_uart_set_flow_control(hu, false);
/* Give to controller time to boot/shutdown */
if (on)
msleep(100);
else
msleep(10);
return 0;
}
