diff options
| author | Abhilash Jindal <klock.android@gmail.com> | 2015-08-11 17:22:57 +0200 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@osg.samsung.com> | 2015-08-16 18:29:59 +0200 |
| commit | 82fde1a98eb9866347a1d3543fac4ab9a69aeb7d (patch) | |
| tree | 2ba862a50bb000695983bf779c34b5cdf81d3bae /drivers/media | |
| parent | [media] zoran: Use monotonic time (diff) | |
| download | linux-82fde1a98eb9866347a1d3543fac4ab9a69aeb7d.tar.xz linux-82fde1a98eb9866347a1d3543fac4ab9a69aeb7d.zip | |
[media] bt8xxx: Use monotonic time
Wall time obtained from do_gettimeofday is susceptible to sudden jumps due to
user setting the time or due to NTP.
Monotonic time is constantly increasing time better suited for comparing two
timestamps.
Signed-off-by: Abhilash Jindal <klock.android@gmail.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Diffstat (limited to 'drivers/media')
| -rw-r--r-- | drivers/media/pci/bt8xx/bttv-input.c | 21 | ||||
| -rw-r--r-- | drivers/media/pci/bt8xx/bttvp.h | 2 |
2 files changed, 9 insertions, 14 deletions
diff --git a/drivers/media/pci/bt8xx/bttv-input.c b/drivers/media/pci/bt8xx/bttv-input.c index 67c8d6b2c335..a75c53da224a 100644 --- a/drivers/media/pci/bt8xx/bttv-input.c +++ b/drivers/media/pci/bt8xx/bttv-input.c @@ -194,21 +194,18 @@ static u32 bttv_rc5_decode(unsigned int code) static void bttv_rc5_timer_end(unsigned long data) { struct bttv_ir *ir = (struct bttv_ir *)data; - struct timeval tv; + ktime_t tv; u32 gap, rc5, scancode; u8 toggle, command, system; /* get time */ - do_gettimeofday(&tv); + tv = ktime_get(); + gap = ktime_to_us(ktime_sub(tv, ir->base_time)); /* avoid overflow with gap >1s */ - if (tv.tv_sec - ir->base_time.tv_sec > 1) { + if (gap > USEC_PER_SEC) { gap = 200000; - } else { - gap = 1000000 * (tv.tv_sec - ir->base_time.tv_sec) + - tv.tv_usec - ir->base_time.tv_usec; } - /* signal we're ready to start a new code */ ir->active = false; @@ -249,7 +246,7 @@ static void bttv_rc5_timer_end(unsigned long data) static int bttv_rc5_irq(struct bttv *btv) { struct bttv_ir *ir = btv->remote; - struct timeval tv; + ktime_t tv; u32 gpio; u32 gap; unsigned long current_jiffies; @@ -259,14 +256,12 @@ static int bttv_rc5_irq(struct bttv *btv) /* get time of bit */ current_jiffies = jiffies; - do_gettimeofday(&tv); + tv = ktime_get(); + gap = ktime_to_us(ktime_sub(tv, ir->base_time)); /* avoid overflow with gap >1s */ - if (tv.tv_sec - ir->base_time.tv_sec > 1) { + if (gap > USEC_PER_SEC) { gap = 200000; - } else { - gap = 1000000 * (tv.tv_sec - ir->base_time.tv_sec) + - tv.tv_usec - ir->base_time.tv_usec; } dprintk("RC5 IRQ: gap %d us for %s\n", diff --git a/drivers/media/pci/bt8xx/bttvp.h b/drivers/media/pci/bt8xx/bttvp.h index a444cfb35c0b..31bf79d3b0d2 100644 --- a/drivers/media/pci/bt8xx/bttvp.h +++ b/drivers/media/pci/bt8xx/bttvp.h @@ -140,7 +140,7 @@ struct bttv_ir { bool rc5_gpio; /* Is RC5 legacy GPIO enabled? */ u32 last_bit; /* last raw bit seen */ u32 code; /* raw code under construction */ - struct timeval base_time; /* time of last seen code */ + ktime_t base_time; /* time of last seen code */ bool active; /* building raw code */ }; |