Hi Matthias,
On 2019-01-19 06:01, Matthias Kaehlcke wrote:
On Fri, Jan 18, 2019 at 10:44:16AM +0100, Johan Hovold wrote:
On Thu, Jan 17, 2019 at 09:21:09AM -0800, Matthias Kaehlcke wrote:
> I observed that the qcom_geni_serial driver doesn't raise RTS with
> flow control disabled. It seems we have to investigate why that's the
> case. I agree that the driver should be platform agnostic.
Sounds like a driver bug, unless the hardware is just "odd". The
driver implementation of this looks very non-standard judging from a
quick peek.
In fact, qcom_geni_serial_get_mctrl() is currently a no-op if hardware
flow control is not enabled:
if (uart_console(uport) || !uart_cts_enabled(uport))
return;
Perhaps dropping the !uart_cts_enabled() test is sufficient.
Thanks for taking a look Johan, that was indeed the problem (also
in set_mctrl()). I posted a fix:
https://lore.kernel.org/patchwork/patch/1033611/
Balakrishna, the following (applied on top of your patch) works for me
with the UART patch above:
[Bala]: will test and update BT patch accordingly.
diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
index 9d5e41f159c78f..60bfdf01f72841 100644
--- a/drivers/bluetooth/hci_qca.c
+++ b/drivers/bluetooth/hci_qca.c
@@ -1080,7 +1080,7 @@ static int qca_set_speed(struct hci_uart *hu,
enum qca_speed_type speed_type)
{
unsigned int speed, qca_baudrate;
struct qca_serdev *qcadev;
- int ret;
+ int ret = 0;
if (speed_type == QCA_INIT_SPEED) {
speed = qca_get_speed(hu, QCA_INIT_SPEED);
@@ -1097,22 +1097,27 @@ static int qca_set_speed(struct hci_uart *hu,
enum qca_speed_type speed_type)
* the old speed.
*/
qcadev = serdev_device_get_drvdata(hu->serdev);
- if (qcadev->btsoc_type == QCA_WCN3990)
+ if (qcadev->btsoc_type == QCA_WCN3990) {
+ hci_uart_set_flow_control(hu, true);
serdev_device_set_rts(hu->serdev, false);
+ }
qca_baudrate = qca_get_baudrate_value(speed);
bt_dev_dbg(hu->hdev, "Set UART speed to %d", speed);
ret = qca_set_baudrate(hu->hdev, qca_baudrate);
if (ret)
- return ret;
+ goto out;
host_set_baudrate(hu, speed);
- if (qcadev->btsoc_type == QCA_WCN3990)
+out:
+ if (qcadev->btsoc_type == QCA_WCN3990) {
+ hci_uart_set_flow_control(hu, false);
serdev_device_set_rts(hu->serdev, true);
+ }
}
- return 0;
+ return ret;
}
static int qca_wcn3990_init(struct hci_uart *hu)
--
Regards
Balakrishna.
