From: Johan Hovold Date: Thu, 2 Jan 2014 21:49:26 +0000 (+0100) Subject: USB: cypress_m8: only wake up MSR queue on changes X-Git-Tag: v3.14-rc1~148^2~48 X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=7603381e3e7ffebe8c0b46c416fe0f88e13b4d34;p=~emulex%2Finfiniband.git USB: cypress_m8: only wake up MSR queue on changes Only wake up MSR wait queue on actual modem-status changes. Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/serial/cypress_m8.c b/drivers/usb/serial/cypress_m8.c index 558605d646f..07e00339861 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 68bfd5197a6..119d2e17077 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 */