[PATCH v2 4/6] irda: nsc-ircc: Replace timeval with ktime_t

From: Chunyan Zhang
Date: Wed Jan 07 2015 - 23:02:57 EST


The nsc ircc 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@xxxxxxxxxx>
Reviewed-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/net/irda/nsc-ircc.c | 7 ++-----
drivers/net/irda/nsc-ircc.h | 5 ++---
2 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/net/irda/nsc-ircc.c b/drivers/net/irda/nsc-ircc.c
index e7317b1..dc0dbd8 100644
--- a/drivers/net/irda/nsc-ircc.c
+++ b/drivers/net/irda/nsc-ircc.c
@@ -1501,10 +1501,7 @@ static netdev_tx_t nsc_ircc_hard_xmit_fir(struct sk_buff *skb,
mtt = irda_get_mtt(skb);
if (mtt) {
/* Check how much time we have used already */
- do_gettimeofday(&self->now);
- diff = self->now.tv_usec - self->stamp.tv_usec;
- if (diff < 0)
- diff += 1000000;
+ diff = ktime_us_delta(ktime_get(), self->stamp);

/* Check if the mtt is larger than the time we have
* already used by all the protocol processing
@@ -1867,7 +1864,7 @@ static int nsc_ircc_dma_receive_complete(struct nsc_ircc_cb *self, int iobase)
* 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();

skb = dev_alloc_skb(len+1);
if (skb == NULL) {
diff --git a/drivers/net/irda/nsc-ircc.h b/drivers/net/irda/nsc-ircc.h
index 32fa582..7be5acb 100644
--- a/drivers/net/irda/nsc-ircc.h
+++ b/drivers/net/irda/nsc-ircc.h
@@ -28,7 +28,7 @@
#ifndef NSC_IRCC_H
#define NSC_IRCC_H

-#include <linux/time.h>
+#include <linux/ktime.h>

#include <linux/spinlock.h>
#include <linux/pm.h>
@@ -263,8 +263,7 @@ struct nsc_ircc_cb {

__u8 ier; /* Interrupt enable register */

- struct timeval stamp;
- struct timeval now;
+ ktime_t stamp;

spinlock_t lock; /* For serializing operations */

--
1.7.9.5

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