Implement Fintek f81534 break on/off with LCR register. It's the same with 16550A LCR register layout.
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_ker...@gmail.com> --- drivers/usb/serial/f81534.c | 46 +++++++++++++++++++++++++++++++++++++++------ 1 file changed, 40 insertions(+), 6 deletions(-) diff --git a/drivers/usb/serial/f81534.c b/drivers/usb/serial/f81534.c index 3f47afa..9ea407d 100644 --- a/drivers/usb/serial/f81534.c +++ b/drivers/usb/serial/f81534.c @@ -128,11 +128,13 @@ struct f81534_serial_private { struct f81534_port_private { struct mutex mcr_mutex; + struct mutex lcr_mutex; struct work_struct lsr_work; struct usb_serial_port *port; unsigned long tx_empty; spinlock_t msr_lock; u8 shadow_mcr; + u8 shadow_lcr; u8 shadow_msr; u8 phy_num; }; @@ -465,6 +467,7 @@ static u32 f81534_calc_baud_divisor(u32 baudrate, u32 clockrate) static int f81534_set_port_config(struct usb_serial_port *port, u32 baudrate, u8 lcr) { + struct f81534_port_private *port_priv = usb_get_serial_port_data(port); u32 divisor; int status; u8 value; @@ -493,35 +496,64 @@ static int f81534_set_port_config(struct usb_serial_port *port, u32 baudrate, } divisor = f81534_calc_baud_divisor(baudrate, F81534_MAX_BAUDRATE); + + mutex_lock(&port_priv->lcr_mutex); + value = UART_LCR_DLAB; status = f81534_set_port_register(port, F81534_LINE_CONTROL_REG, value); if (status) { dev_err(&port->dev, "%s: set LCR failed\n", __func__); - return status; + goto final; } value = divisor & 0xff; status = f81534_set_port_register(port, F81534_DIVISOR_LSB_REG, value); if (status) { dev_err(&port->dev, "%s: set DLAB LSB failed\n", __func__); - return status; + goto final; } value = (divisor >> 8) & 0xff; status = f81534_set_port_register(port, F81534_DIVISOR_MSB_REG, value); if (status) { dev_err(&port->dev, "%s: set DLAB MSB failed\n", __func__); - return status; + goto final; } - status = f81534_set_port_register(port, F81534_LINE_CONTROL_REG, lcr); + value = lcr | (port_priv->shadow_lcr & UART_LCR_SBC); + status = f81534_set_port_register(port, F81534_LINE_CONTROL_REG, + value); if (status) { dev_err(&port->dev, "%s: set LCR failed\n", __func__); - return status; + goto final; } - return 0; + port_priv->shadow_lcr = value; +final: + mutex_unlock(&port_priv->lcr_mutex); + return status; +} + +static void f81534_break_ctl(struct tty_struct *tty, int break_state) +{ + struct usb_serial_port *port = tty->driver_data; + struct f81534_port_private *port_priv = usb_get_serial_port_data(port); + int status; + + mutex_lock(&port_priv->lcr_mutex); + + if (break_state) + port_priv->shadow_lcr |= UART_LCR_SBC; + else + port_priv->shadow_lcr &= ~UART_LCR_SBC; + + status = f81534_set_port_register(port, F81534_LINE_CONTROL_REG, + port_priv->shadow_lcr); + if (status) + dev_err(&port->dev, "set break failed: %x\n", status); + + mutex_unlock(&port_priv->lcr_mutex); } static int f81534_update_mctrl(struct usb_serial_port *port, unsigned int set, @@ -1193,6 +1225,7 @@ static int f81534_port_probe(struct usb_serial_port *port) spin_lock_init(&port_priv->msr_lock); mutex_init(&port_priv->mcr_mutex); + mutex_init(&port_priv->lcr_mutex); INIT_WORK(&port_priv->lsr_work, f81534_lsr_worker); /* Assign logic-to-phy mapping */ @@ -1359,6 +1392,7 @@ static struct usb_serial_driver f81534_device = { .attach = f81534_attach, .port_probe = f81534_port_probe, .port_remove = f81534_port_remove, + .break_ctl = f81534_break_ctl, .dtr_rts = f81534_dtr_rts, .process_read_urb = f81534_process_read_urb, .ioctl = f81534_ioctl, -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html