Return-Path: From: Ilya Faenson To: Marcel Holtmann CC: , Arend van Spriel , Ilya Faenson Subject: [PATCH v2 2/5] H4 line discipline enhancements Date: Wed, 10 Jun 2015 16:05:17 -0400 Message-ID: <1433966720-17482-3-git-send-email-ifaenson@broadcom.com> In-Reply-To: <1433966720-17482-1-git-send-email-ifaenson@broadcom.com> References: <1433966720-17482-1-git-send-email-ifaenson@broadcom.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Added the ability to flow control the UART and improved the UART baud rate setting. Signed-off-by: Ilya Faenson --- 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