diff options
| -rw-r--r-- | drivers/usb/serial/cypress_m8.c | 5 | ||||
| -rw-r--r-- | drivers/usb/serial/cypress_m8.h | 1 |
2 files changed, 5 insertions, 1 deletions
diff --git a/drivers/usb/serial/cypress_m8.c b/drivers/usb/serial/cypress_m8.c index 558605d646f3..07e003398613 100644 --- a/drivers/usb/serial/cypress_m8.c +++ b/drivers/usb/serial/cypress_m8.c @@ -1187,7 +1187,10 @@ static void cypress_read_int_callback(struct urb *urb) if (priv->current_status != priv->prev_status) { priv->diff_status |= priv->current_status ^ priv->prev_status; - wake_up_interruptible(&port->port.delta_msr_wait); + + if (priv->diff_status & UART_MSR_MASK) + wake_up_interruptible(&port->port.delta_msr_wait); + priv->prev_status = priv->current_status; } spin_unlock_irqrestore(&priv->lock, flags); diff --git a/drivers/usb/serial/cypress_m8.h b/drivers/usb/serial/cypress_m8.h index 68bfd5197a63..119d2e17077b 100644 --- a/drivers/usb/serial/cypress_m8.h +++ b/drivers/usb/serial/cypress_m8.h @@ -66,6 +66,7 @@ #define CONTROL_RTS 0x10 /* request to send */ #define CONTROL_RESET 0x08 /* sent with output report */ +#define UART_MSR_MASK 0xf0 #define UART_RI 0x80 /* ring indicator */ #define UART_CD 0x40 /* carrier detect */ #define UART_DSR 0x20 /* data set ready */ |
