irda: irda-usb: Replace timeval with ktime_t

The irda usb driver uses 'timeval', which we try to remove in the kernel
because all 32-bit time types will break in the year 2038.

This patch also changes do_gettimeofday() to ktime_get() accordingly,
since ktime_get returns a ktime_t, but do_gettimeofday returns a
struct timeval, and the other reason is that ktime_get() uses
the monotonic clock.

This patch uses ktime_us_delta to get the elapsed time, and in this
way it no longer needs to check for the overflow, because
ktime_us_delta returns time difference of microsecond.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 4 insertions, 11 deletions

diff --git a/drivers/net/irda/irda-usb.c b/drivers/net/irda/irda-usb.c
index 48b2f9a321b7..f6c916312577 100644
--- a/drivers/net/irda/irda-usb.c
+++ b/drivers/net/irda/irda-usb.c
@@ -495,18 +495,12 @@ static netdev_tx_t irda_usb_hard_xmit(struct sk_buff *skb,
                 mtt = irda_get_mtt(skb);
                 if (mtt) {
                         int diff;
-                        do_gettimeofday(&self->now);
-                        diff = self->now.tv_usec - self->stamp.tv_usec;
+                        diff = ktime_us_delta(ktime_get(), self->stamp);
 #ifdef IU_USB_MIN_RTT
                         /* Factor in USB delays -> Get rid of udelay() that
                          * would be lost in the noise - Jean II */
                         diff += IU_USB_MIN_RTT;
 #endif /* IU_USB_MIN_RTT */
-                        /* If the usec counter did wraparound, the diff will
-                         * go negative (tv_usec is a long), so we need to
-                         * correct it by one second. Jean II */
-                        if (diff < 0)
-                                diff += 1000000;
 
                         /* Check if the mtt is larger than the time we have
                          * already used by all the protocol processing
@@ -869,7 +863,7 @@ static void irda_usb_receive(struct urb *urb)
          * reduce the min turn time a bit since we will know
          * how much time we have used for protocol processing
          */
-        do_gettimeofday(&self->stamp);
+        self->stamp = ktime_get();
 
         /* Check if we need to copy the data to a new skb or not.
          * For most frames, we use ZeroCopy and pass the already
diff --git a/drivers/net/irda/irda-usb.h b/drivers/net/irda/irda-usb.h
index 58ddb5214916..8ac389fa9348 100644
--- a/drivers/net/irda/irda-usb.h
+++ b/drivers/net/irda/irda-usb.h
@@ -29,7 +29,7 @@
  *
  *****************************************************************************/
 
-#include <linux/time.h>
+#include <linux/ktime.h>
 
 #include <net/irda/irda.h>
 #include <net/irda/irda_device.h>      /* struct irlap_cb */
@@ -157,8 +157,7 @@ struct irda_usb_cb {
         char *speed_buff;               /* Buffer for speed changes */
         char *tx_buff;
 
-        struct timeval stamp;
-        struct timeval now;
+        ktime_t stamp;
 
         spinlock_t lock;                /* For serializing Tx operations */