Added the ability to flow control the UART and improved the
UART baud rate setting.
Signed-off-by: Ilya Faenson <ifaenson@xxxxxxxxxxxx>
---
drivers/bluetooth/hci_ldisc.c | 66 +++++++++++++++++++++++++++++++++++++++++--
drivers/bluetooth/hci_uart.h | 1 +
2 files changed, 65 insertions(+), 2 deletions(-)
diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
index ac87346..f86e973 100644
--- a/drivers/bluetooth/hci_ldisc.c
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -266,20 +266,82 @@ static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
return 0;
}
+/* Flow control or un-flow control the device */
+void hci_uart_set_flow_control(struct hci_uart *hu, bool enable)
+{
+ struct tty_struct *tty = hu->tty;
+ struct ktermios ktermios;
+ int status;
+ unsigned int set = 0;
+ unsigned int clear = 0;
+
+ if (enable) {
+ /* Disable hardware flow control */
+ ktermios = tty->termios;
+ ktermios.c_cflag &= ~CRTSCTS;
+ status = tty_set_termios(tty, &ktermios);
+ BT_DBG("Disabling hardware flow control: %s", status ?
+ "failed" : "success");
+
+ /* Clear RTS to prevent the device from sending */
+ /* Most UARTs need OUT2 to enable interrupts */
+ status = tty->driver->ops->tiocmget(tty);
+ BT_DBG("Current tiocm 0x%x", status);
+
+ set &= ~(TIOCM_OUT2 | TIOCM_RTS);
+ clear = ~set;
+ set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
+ TIOCM_OUT2 | TIOCM_LOOP;
+ clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
+ TIOCM_OUT2 | TIOCM_LOOP;
+ status = tty->driver->ops->tiocmset(tty, set, clear);
+ BT_DBG("Clearing RTS: %s", status ? "failed" : "success");
+ } else {
+ /* Set RTS to allow the device to send again */
+ status = tty->driver->ops->tiocmget(tty);
+ BT_DBG("Current tiocm 0x%x", status);
+
+ set |= (TIOCM_OUT2 | TIOCM_RTS);
+ clear = ~set;
+ set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
+ TIOCM_OUT2 | TIOCM_LOOP;
+ clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
+ TIOCM_OUT2 | TIOCM_LOOP;
+ status = tty->driver->ops->tiocmset(tty, set, clear);
+ BT_DBG("Setting RTS: %s", status ? "failed" : "success");
+
+ /* Re-enable hardware flow control */
+ ktermios = tty->termios;
+ ktermios.c_cflag |= CRTSCTS;
+ status = tty_set_termios(tty, &ktermios);
+ BT_DBG("Enabling hardware flow control: %s", status ?
+ "failed" : "success");
+ }
+}
+
void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
{
struct tty_struct *tty = hu->tty;
struct ktermios ktermios;
+ /* Bring the UART into a known state with a given baud rate */
ktermios = tty->termios;
ktermios.c_cflag &= ~CBAUD;
- ktermios.c_cflag |= BOTHER;
+ ktermios.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP
+ | INLCR | IGNCR | ICRNL | IXON);
+ ktermios.c_oflag &= ~OPOST;
+ ktermios.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
+ ktermios.c_cflag &= ~(CSIZE | PARENB | CBAUD);
+ ktermios.c_cflag |= CS8;
+ ktermios.c_cflag |= CRTSCTS;
tty_termios_encode_baud_rate(&ktermios, speed, speed);
/* tty_set_termios() return not checked as it is always 0 */
tty_set_termios(tty, &ktermios);
- BT_DBG("%s: New tty speed: %d", hu->hdev->name, tty->termios.c_ispeed);
+ BT_DBG("%s: New tty speeds: %d/%d, cflag: 0x%x", hu->hdev->name,
+ tty->termios.c_ispeed, tty->termios.c_ospeed,
+ tty->termios.c_cflag);
}
static int hci_uart_setup(struct hci_dev *hdev)
diff --git a/drivers/bluetooth/hci_uart.h b/drivers/bluetooth/hci_uart.h
index e9f970c..8ef1881 100644
--- a/drivers/bluetooth/hci_uart.h
+++ b/drivers/bluetooth/hci_uart.h
@@ -100,6 +100,7 @@ int hci_uart_unregister_proto(const struct hci_uart_proto *p);
int hci_uart_tx_wakeup(struct hci_uart *hu);
int hci_uart_init_ready(struct hci_uart *hu);
void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed);
+void hci_uart_set_flow_control(struct hci_uart *hu, bool enable);
#ifdef CONFIG_BT_HCIUART_H4
int h4_init(void);
--
1.9.1
--
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