| Message ID | 20190124120808.8275-3-bgodavar@codeaurora.org (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | Andy Gross |
| Headers | show |
| Series | Bug fixes for Qualcomm BT chip wcn3990. | expand |
Hi Balakrishna, On Thu, Jan 24, 2019 at 05:38:07PM +0530, Balakrishna Godavarthi wrote: > This patch will help to stop frame reassembly errors while changing > the baudrate. This is because host send a change baudrate request > command to the chip with 115200 bps, Whereas chip will change their > UART clocks to the enable for new baudrate and sends the response > for the change request command with newer baudrate, On host side > we are still operating in 115200 bps which results of reading garbage > data. Here we are pulling RTS line, so that chip we will wait to send data > to host until host change its baudrate. > > Signed-off-by: Balakrishna Godavarthi <bgodavar@codeaurora.org> > Tested-by: Matthias Kaehlcke <mka@chromium.org> > Reviewed-by: Matthias Kaehlcke <mka@chromium.org> > --- > Changes in v9: > * disabled flow control while setting the baudrate of HOST and chip. > --- > drivers/bluetooth/hci_qca.c | 24 +++++++++++++----------- > 1 file changed, 13 insertions(+), 11 deletions(-) > > diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c > index c08f4d105e73..6b5bcd44e24c 100644 > --- a/drivers/bluetooth/hci_qca.c > +++ b/drivers/bluetooth/hci_qca.c > @@ -964,7 +964,6 @@ static int qca_set_baudrate(struct hci_dev *hdev, uint8_t baudrate) > struct hci_uart *hu = hci_get_drvdata(hdev); > struct qca_data *qca = hu->priv; > struct sk_buff *skb; > - struct qca_serdev *qcadev; > u8 cmd[] = { 0x01, 0x48, 0xFC, 0x01, 0x00 }; > > if (baudrate > QCA_BAUDRATE_3200000) > @@ -978,13 +977,6 @@ static int qca_set_baudrate(struct hci_dev *hdev, uint8_t baudrate) > return -ENOMEM; > } > > - /* Disabling hardware flow control is mandatory while > - * sending change baudrate request to wcn3990 SoC. > - */ > - qcadev = serdev_device_get_drvdata(hu->serdev); > - if (qcadev->btsoc_type == QCA_WCN3990) > - hci_uart_set_flow_control(hu, true); > - > /* Assign commands to change baudrate and packet type. */ > skb_put_data(skb, cmd, sizeof(cmd)); > hci_skb_pkt_type(skb) = HCI_COMMAND_PKT; > @@ -1000,9 +992,6 @@ static int qca_set_baudrate(struct hci_dev *hdev, uint8_t baudrate) > schedule_timeout(msecs_to_jiffies(BAUDRATE_SETTLE_TIMEOUT_MS)); > set_current_state(TASK_RUNNING); > > - if (qcadev->btsoc_type == QCA_WCN3990) > - hci_uart_set_flow_control(hu, false); > - > return 0; > } > > @@ -1089,6 +1078,7 @@ static int qca_check_speeds(struct hci_uart *hu) > 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; > > if (speed_type == QCA_INIT_SPEED) { > @@ -1100,6 +1090,15 @@ static int qca_set_speed(struct hci_uart *hu, enum qca_speed_type speed_type) > if (!speed) > return 0; > > + /* Deassert RTS while changing the baudrate of chip and host. > + * This will prevent chip from transmitting its response with > + * the new baudrate while the host port is still operating at > + * the old speed. > + */ It is not necessarily evident which action deasserts RTS, I suggest to rephrase it to something like: "Disable flow control for wcn3990 to deassert RTS while ... " > + qcadev = serdev_device_get_drvdata(hu->serdev); > + if (qcadev->btsoc_type == QCA_WCN3990) > + hci_uart_set_flow_control(hu, true); > + > 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); flow control should be re-enabled in the error path. Cheers Matthias
Hi Matthias, On 2019-01-25 05:42, Matthias Kaehlcke wrote: > Hi Balakrishna, > > On Thu, Jan 24, 2019 at 05:38:07PM +0530, Balakrishna Godavarthi wrote: >> This patch will help to stop frame reassembly errors while changing >> the baudrate. This is because host send a change baudrate request >> command to the chip with 115200 bps, Whereas chip will change their >> UART clocks to the enable for new baudrate and sends the response >> for the change request command with newer baudrate, On host side >> we are still operating in 115200 bps which results of reading garbage >> data. Here we are pulling RTS line, so that chip we will wait to send >> data >> to host until host change its baudrate. >> >> Signed-off-by: Balakrishna Godavarthi <bgodavar@codeaurora.org> >> Tested-by: Matthias Kaehlcke <mka@chromium.org> >> Reviewed-by: Matthias Kaehlcke <mka@chromium.org> >> --- >> Changes in v9: >> * disabled flow control while setting the baudrate of HOST and chip. >> --- >> drivers/bluetooth/hci_qca.c | 24 +++++++++++++----------- >> 1 file changed, 13 insertions(+), 11 deletions(-) >> >> diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c >> index c08f4d105e73..6b5bcd44e24c 100644 >> --- a/drivers/bluetooth/hci_qca.c >> +++ b/drivers/bluetooth/hci_qca.c >> @@ -964,7 +964,6 @@ static int qca_set_baudrate(struct hci_dev *hdev, >> uint8_t baudrate) >> struct hci_uart *hu = hci_get_drvdata(hdev); >> struct qca_data *qca = hu->priv; >> struct sk_buff *skb; >> - struct qca_serdev *qcadev; >> u8 cmd[] = { 0x01, 0x48, 0xFC, 0x01, 0x00 }; >> >> if (baudrate > QCA_BAUDRATE_3200000) >> @@ -978,13 +977,6 @@ static int qca_set_baudrate(struct hci_dev *hdev, >> uint8_t baudrate) >> return -ENOMEM; >> } >> >> - /* Disabling hardware flow control is mandatory while >> - * sending change baudrate request to wcn3990 SoC. >> - */ >> - qcadev = serdev_device_get_drvdata(hu->serdev); >> - if (qcadev->btsoc_type == QCA_WCN3990) >> - hci_uart_set_flow_control(hu, true); >> - >> /* Assign commands to change baudrate and packet type. */ >> skb_put_data(skb, cmd, sizeof(cmd)); >> hci_skb_pkt_type(skb) = HCI_COMMAND_PKT; >> @@ -1000,9 +992,6 @@ static int qca_set_baudrate(struct hci_dev *hdev, >> uint8_t baudrate) >> schedule_timeout(msecs_to_jiffies(BAUDRATE_SETTLE_TIMEOUT_MS)); >> set_current_state(TASK_RUNNING); >> >> - if (qcadev->btsoc_type == QCA_WCN3990) >> - hci_uart_set_flow_control(hu, false); >> - >> return 0; >> } >> >> @@ -1089,6 +1078,7 @@ static int qca_check_speeds(struct hci_uart *hu) >> 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; >> >> if (speed_type == QCA_INIT_SPEED) { >> @@ -1100,6 +1090,15 @@ static int qca_set_speed(struct hci_uart *hu, >> enum qca_speed_type speed_type) >> if (!speed) >> return 0; >> >> + /* Deassert RTS while changing the baudrate of chip and host. >> + * This will prevent chip from transmitting its response with >> + * the new baudrate while the host port is still operating at >> + * the old speed. >> + */ > > It is not necessarily evident which action deasserts RTS, I suggest to > rephrase it to something like: > > "Disable flow control for wcn3990 to deassert RTS while ... " > [Bala]: will update. >> + qcadev = serdev_device_get_drvdata(hu->serdev); >> + if (qcadev->btsoc_type == QCA_WCN3990) >> + hci_uart_set_flow_control(hu, true); >> + >> 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); > > flow control should be re-enabled in the error path. > > Cheers > > Matthias [Bala; will update.
diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c index c08f4d105e73..6b5bcd44e24c 100644 --- a/drivers/bluetooth/hci_qca.c +++ b/drivers/bluetooth/hci_qca.c @@ -964,7 +964,6 @@ static int qca_set_baudrate(struct hci_dev *hdev, uint8_t baudrate) struct hci_uart *hu = hci_get_drvdata(hdev); struct qca_data *qca = hu->priv; struct sk_buff *skb; - struct qca_serdev *qcadev; u8 cmd[] = { 0x01, 0x48, 0xFC, 0x01, 0x00 }; if (baudrate > QCA_BAUDRATE_3200000) @@ -978,13 +977,6 @@ static int qca_set_baudrate(struct hci_dev *hdev, uint8_t baudrate) return -ENOMEM; } - /* Disabling hardware flow control is mandatory while - * sending change baudrate request to wcn3990 SoC. - */ - qcadev = serdev_device_get_drvdata(hu->serdev); - if (qcadev->btsoc_type == QCA_WCN3990) - hci_uart_set_flow_control(hu, true); - /* Assign commands to change baudrate and packet type. */ skb_put_data(skb, cmd, sizeof(cmd)); hci_skb_pkt_type(skb) = HCI_COMMAND_PKT; @@ -1000,9 +992,6 @@ static int qca_set_baudrate(struct hci_dev *hdev, uint8_t baudrate) schedule_timeout(msecs_to_jiffies(BAUDRATE_SETTLE_TIMEOUT_MS)); set_current_state(TASK_RUNNING); - if (qcadev->btsoc_type == QCA_WCN3990) - hci_uart_set_flow_control(hu, false); - return 0; } @@ -1089,6 +1078,7 @@ static int qca_check_speeds(struct hci_uart *hu) 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; if (speed_type == QCA_INIT_SPEED) { @@ -1100,6 +1090,15 @@ static int qca_set_speed(struct hci_uart *hu, enum qca_speed_type speed_type) if (!speed) return 0; + /* Deassert RTS while changing the baudrate of chip and host. + * This will prevent chip from transmitting its response with + * the new baudrate while the host port is still operating at + * the old speed. + */ + qcadev = serdev_device_get_drvdata(hu->serdev); + if (qcadev->btsoc_type == QCA_WCN3990) + hci_uart_set_flow_control(hu, true); + 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); @@ -1107,6 +1106,9 @@ static int qca_set_speed(struct hci_uart *hu, enum qca_speed_type speed_type) return ret; host_set_baudrate(hu, speed); + + if (qcadev->btsoc_type == QCA_WCN3990) + hci_uart_set_flow_control(hu, false); } return 0;