Bluetooth: hci_uart: Add new line discipline enhancements
authorIlya Faenson <ifaenson@broadcom.com>
Wed, 17 Jun 2015 21:30:56 +0000 (17:30 -0400)
committerMarcel Holtmann <marcel@holtmann.org>
Wed, 17 Jun 2015 21:44:49 +0000 (23:44 +0200)
Added the ability to flow control the UART, improved the UART baud
rate setting, transferred the speeds into line discipline from the
protocol and introduced the tty init function.

Signed-off-by: Ilya Faenson <ifaenson@broadcom.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
drivers/bluetooth/hci_ldisc.c
drivers/bluetooth/hci_uart.h

index ac87346ce9d78593dc8755379ffe27838773f2ef..590bd8e66bfb574fdf614dab3db46f053ba063fc 100644 (file)
@@ -266,6 +266,85 @@ 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_speeds(struct hci_uart *hu, unsigned int init_speed,
+                        unsigned int oper_speed)
+{
+       hu->init_speed = init_speed;
+       hu->oper_speed = oper_speed;
+}
+
+void hci_uart_init_tty(struct hci_uart *hu)
+{
+       struct tty_struct *tty = hu->tty;
+       struct ktermios ktermios;
+
+       /* Bring the UART into a known 8 bits no parity hw fc state */
+       ktermios = tty->termios;
+       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);
+       ktermios.c_cflag |= CS8;
+       ktermios.c_cflag |= CRTSCTS;
+
+       /* tty_set_termios() return not checked as it is always 0 */
+       tty_set_termios(tty, &ktermios);
+}
+
 void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
 {
        struct tty_struct *tty = hu->tty;
@@ -273,13 +352,13 @@ void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
 
        ktermios = tty->termios;
        ktermios.c_cflag &= ~CBAUD;
-       ktermios.c_cflag |= BOTHER;
        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", hu->hdev->name,
+              tty->termios.c_ispeed, tty->termios.c_ospeed);
 }
 
 static int hci_uart_setup(struct hci_dev *hdev)
@@ -287,15 +366,32 @@ static int hci_uart_setup(struct hci_dev *hdev)
        struct hci_uart *hu = hci_get_drvdata(hdev);
        struct hci_rp_read_local_version *ver;
        struct sk_buff *skb;
+       unsigned int speed;
        int err;
 
+       /* Init speed if any */
        if (hu->proto->init_speed)
-               hci_uart_set_baudrate(hu, hu->proto->init_speed);
+               speed = hu->proto->init_speed;
+       else if (hu->init_speed)
+               speed = hu->init_speed;
+       else
+               speed = 0;
+
+       if (speed)
+               hci_uart_set_baudrate(hu, speed);
+
+       /* Operational speed if any */
+       if (hu->proto->oper_speed)
+               speed = hu->proto->oper_speed;
+       else if (hu->oper_speed)
+               speed = hu->oper_speed;
+       else
+               speed = 0;
 
-       if (hu->proto->set_baudrate && hu->proto->oper_speed) {
-               err = hu->proto->set_baudrate(hu, hu->proto->oper_speed);
+       if (hu->proto->set_baudrate && speed) {
+               err = hu->proto->set_baudrate(hu, speed);
                if (!err)
-                       hci_uart_set_baudrate(hu, hu->proto->oper_speed);
+                       hci_uart_set_baudrate(hu, speed);
        }
 
        if (hu->proto->setup)
index e9f970c25304bd5642617814c9cf723883f5fca8..ce9c670956f54d414aadaec5f9810fac7e058abd 100644 (file)
@@ -85,6 +85,9 @@ struct hci_uart {
        struct sk_buff          *tx_skb;
        unsigned long           tx_state;
        spinlock_t              rx_lock;
+
+       unsigned int init_speed;
+       unsigned int oper_speed;
 };
 
 /* HCI_UART proto flag bits */
@@ -99,7 +102,11 @@ int hci_uart_register_proto(const struct hci_uart_proto *p);
 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_init_tty(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);
+void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,
+                        unsigned int oper_speed);
 
 #ifdef CONFIG_BT_HCIUART_H4
 int h4_init(void);