[PATCH V3] hp_sdc: convert struct timeval to ktime_t

From: WEN Pingbo
Date: Fri Oct 23 2015 - 07:30:04 EST


1. struct timeval is not y2038 safe, convert it to ktime_t, and there is no need to handle sec and usec separately

2. hp_sdc.rtv is only used for time diff, monotonic time is better here

Signed-off-by: WEN Pingbo <pingbo.wen@xxxxxxxxxx>
---

Version 2:
Using ktime_t instead of struct timespec64
Version 3:
Commit msg adjustment, and using ktime_to_ns to extract nsecs

drivers/input/serio/hp_sdc.c | 16 ++++++----------
include/linux/hp_sdc.h | 6 +++---
2 files changed, 9 insertions(+), 13 deletions(-)

diff --git a/drivers/input/serio/hp_sdc.c b/drivers/input/serio/hp_sdc.c
index 852858e..17e3725 100644
--- a/drivers/input/serio/hp_sdc.c
+++ b/drivers/input/serio/hp_sdc.c
@@ -193,7 +193,7 @@ static void hp_sdc_take(int irq, void *dev_id, uint8_t status, uint8_t data)
curr->seq[curr->idx++] = status;
curr->seq[curr->idx++] = data;
hp_sdc.rqty -= 2;
- do_gettimeofday(&hp_sdc.rtv);
+ hp_sdc.rtv = ktime_get();

if (hp_sdc.rqty <= 0) {
/* All data has been gathered. */
@@ -306,13 +306,9 @@ static void hp_sdc_tasklet(unsigned long foo)
write_lock_irq(&hp_sdc.rtq_lock);

if (hp_sdc.rcurr >= 0) {
- struct timeval tv;
+ ktime_t time_diff = ktime_sub(ktime_get(), hp_sdc.rtv);

- do_gettimeofday(&tv);
- if (tv.tv_sec > hp_sdc.rtv.tv_sec)
- tv.tv_usec += USEC_PER_SEC;
-
- if (tv.tv_usec - hp_sdc.rtv.tv_usec > HP_SDC_MAX_REG_DELAY) {
+ if (ktime_to_ns(time_diff) > HP_SDC_MAX_REG_DELAY) {
hp_sdc_transaction *curr;
uint8_t tmp;

@@ -321,8 +317,8 @@ static void hp_sdc_tasklet(unsigned long foo)
* we'll need to figure out a way to communicate
* it back to the application. and be less verbose.
*/
- printk(KERN_WARNING PREFIX "read timeout (%ius)!\n",
- (int)(tv.tv_usec - hp_sdc.rtv.tv_usec));
+ printk(KERN_WARNING PREFIX "read timeout (%llins)!\n",
+ ktime_to_ns(time_diff));
curr->idx += hp_sdc.rqty;
hp_sdc.rqty = 0;
tmp = curr->seq[curr->actidx];
@@ -551,7 +547,7 @@ unsigned long hp_sdc_put(void)

/* Start a new read */
hp_sdc.rqty = curr->seq[curr->idx];
- do_gettimeofday(&hp_sdc.rtv);
+ hp_sdc.rtv = ktime_get();
curr->idx++;
/* Still need to lock here in case of spurious irq. */
write_lock_irq(&hp_sdc.rtq_lock);
diff --git a/include/linux/hp_sdc.h b/include/linux/hp_sdc.h
index d392975..348a9b5 100644
--- a/include/linux/hp_sdc.h
+++ b/include/linux/hp_sdc.h
@@ -47,9 +47,9 @@
#endif


-/* No 4X status reads take longer than this (in usec).
+/* No 4X status reads take longer than this (in nsec).
*/
-#define HP_SDC_MAX_REG_DELAY 20000
+#define HP_SDC_MAX_REG_DELAY 20000000

typedef void (hp_sdc_irqhook) (int irq, void *dev_id,
uint8_t status, uint8_t data);
@@ -281,7 +281,7 @@ typedef struct {
hp_sdc_transaction *tq[HP_SDC_QUEUE_LEN]; /* All pending read/writes */

int rcurr, rqty; /* Current read transact in process */
- struct timeval rtv; /* Time when current read started */
+ ktime_t rtv; /* Time when current read started */
int wcurr; /* Current write transact in process */

int dev_err; /* carries status from registration */
--
1.9.1

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