diff mbox

Input: Add support for CLOCK_BOOTTIME

Message ID 1418748994-2875-1-git-send-email-aniroop.mathur@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Aniroop Mathur Dec. 16, 2014, 4:56 p.m. UTC
This patch adds support for CLOCK_BOOTTIME for input event timestamp.
CLOCK_BOOTTIME includes suspend time, so it would allow aplications
to get correct time difference between two events even when system
resumes from suspend state.

Signed-off-by: Aniroop Mathur <a.mathur@samsung.com>
---
 drivers/input/evdev.c | 33 +++++++++++++++++++++------------
 1 file changed, 21 insertions(+), 12 deletions(-)

Comments

Dmitry Torokhov Dec. 17, 2014, 6:20 p.m. UTC | #1
Hi Aniroop,

On Tue, Dec 16, 2014 at 10:26:34PM +0530, Aniroop Mathur wrote:
> This patch adds support for CLOCK_BOOTTIME for input event timestamp.
> CLOCK_BOOTTIME includes suspend time, so it would allow aplications
> to get correct time difference between two events even when system
> resumes from suspend state.
> 
> Signed-off-by: Aniroop Mathur <a.mathur@samsung.com>
> ---
>  drivers/input/evdev.c | 33 +++++++++++++++++++++------------
>  1 file changed, 21 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
> index de05545..7825794 100644
> --- a/drivers/input/evdev.c
> +++ b/drivers/input/evdev.c
> @@ -28,6 +28,13 @@
>  #include <linux/cdev.h>
>  #include "input-compat.h"
>  
> +enum clock_type {
> +	REAL = 0,
> +	MONO,
> +	BOOT,
> +	CLK_MAX
> +};
> +
>  struct evdev {
>  	int open;
>  	struct input_handle handle;
> @@ -108,8 +115,9 @@ static void evdev_queue_syn_dropped(struct evdev_client *client)
>  	struct input_event ev;
>  	ktime_t time;
>  
> -	time = (client->clkid == CLOCK_MONOTONIC) ?
> -		ktime_get() : ktime_get_real();
> +	time = (client->clkid == CLOCK_REALTIME) ?
> +		ktime_get_real() : (client->clkid == CLOCK_MONOTONIC) ?
> +		ktime_get() : ktime_get_boottime();
>  
>  	ev.time = ktime_to_timeval(time);
>  	ev.type = EV_SYN;
> @@ -159,7 +167,7 @@ static void __pass_event(struct evdev_client *client,
>  
>  static void evdev_pass_values(struct evdev_client *client,
>  			const struct input_value *vals, unsigned int count,
> -			ktime_t mono, ktime_t real)
> +			ktime_t *ev_time)
>  {
>  	struct evdev *evdev = client->evdev;
>  	const struct input_value *v;
> @@ -169,8 +177,9 @@ static void evdev_pass_values(struct evdev_client *client,
>  	if (client->revoked)
>  		return;
>  
> -	event.time = ktime_to_timeval(client->clkid == CLOCK_MONOTONIC ?
> -				      mono : real);
> +	event.time = ktime_to_timeval(client->clkid == CLOCK_REALTIME ?
> +			ev_time[REAL] : client->clkid == CLOCK_MONOTONIC ?
> +			ev_time[MONO] : ev_time[BOOT]);

This becomes unwieldy. Should we have client->clk_type instead of
client->clkid and convert CLOCK_* into your EVDEV_CLK_{REAL|MONO|BOOT}
when setting it in ioctl and then do

	event.time = ktime_to_timeval(ev_time[client->clk_offset]);

>  
>  	/* Interrupts are disabled, just acquire the lock. */
>  	spin_lock(&client->buffer_lock);
> @@ -198,21 +207,21 @@ static void evdev_events(struct input_handle *handle,
>  {
>  	struct evdev *evdev = handle->private;
>  	struct evdev_client *client;
> -	ktime_t time_mono, time_real;
> +	ktime_t ev_time[CLK_MAX];
>  
> -	time_mono = ktime_get();
> -	time_real = ktime_mono_to_real(time_mono);
> +	ev_time[MONO] = ktime_get();
> +	ev_time[REAL] = ktime_mono_to_real(ev_time[MONO]);
> +	ev_time[BOOT] = ktime_get_boottime();

I do not think we want to use ktime_get_boottime() here; I'd rather you
use ktime_mono_to_anY(ev_time[MONO], TK_OFFS_BOOT) so that all 3 times
are consistent.

>  
>  	rcu_read_lock();
>  
>  	client = rcu_dereference(evdev->grab);
>  
>  	if (client)
> -		evdev_pass_values(client, vals, count, time_mono, time_real);
> +		evdev_pass_values(client, vals, count, ev_time);
>  	else
>  		list_for_each_entry_rcu(client, &evdev->client_list, node)
> -			evdev_pass_values(client, vals, count,
> -					  time_mono, time_real);
> +			evdev_pass_values(client, vals, count, ev_time);
>  
>  	rcu_read_unlock();
>  }
> @@ -874,7 +883,7 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd,
>  	case EVIOCSCLOCKID:
>  		if (copy_from_user(&i, p, sizeof(unsigned int)))
>  			return -EFAULT;
> -		if (i != CLOCK_MONOTONIC && i != CLOCK_REALTIME)
> +		if (i != CLOCK_MONOTONIC && i != CLOCK_REALTIME && i != CLOCK_BOOTTIME)
>  			return -EINVAL;
>  		client->clkid = i;
>  		return 0;
> -- 
> 1.9.1
> 

Thanks.
Aniroop Mathur Dec. 17, 2014, 9:33 p.m. UTC | #2
Hello Mr. Torokhov,

On Wed, Dec 17, 2014 at 11:50 PM, Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:
> Hi Aniroop,
>
> On Tue, Dec 16, 2014 at 10:26:34PM +0530, Aniroop Mathur wrote:
>> This patch adds support for CLOCK_BOOTTIME for input event timestamp.
>> CLOCK_BOOTTIME includes suspend time, so it would allow aplications
>> to get correct time difference between two events even when system
>> resumes from suspend state.
>>
>> Signed-off-by: Aniroop Mathur <a.mathur@samsung.com>
>> ---
>>  drivers/input/evdev.c | 33 +++++++++++++++++++++------------
>>  1 file changed, 21 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
>> index de05545..7825794 100644
>> --- a/drivers/input/evdev.c
>> +++ b/drivers/input/evdev.c
>> @@ -28,6 +28,13 @@
>>  #include <linux/cdev.h>
>>  #include "input-compat.h"
>>
>> +enum clock_type {
>> +     REAL = 0,
>> +     MONO,
>> +     BOOT,
>> +     CLK_MAX
>> +};
>> +
>>  struct evdev {
>>       int open;
>>       struct input_handle handle;
>> @@ -108,8 +115,9 @@ static void evdev_queue_syn_dropped(struct evdev_client *client)
>>       struct input_event ev;
>>       ktime_t time;
>>
>> -     time = (client->clkid == CLOCK_MONOTONIC) ?
>> -             ktime_get() : ktime_get_real();
>> +     time = (client->clkid == CLOCK_REALTIME) ?
>> +             ktime_get_real() : (client->clkid == CLOCK_MONOTONIC) ?
>> +             ktime_get() : ktime_get_boottime();
>>

Is this okay ?
To improve readabilty,
how about adding a new funtion to get time depending upon clkid like below ?
time = get_clk_time(client->clkid);

static ktime_t get_clk_time(int id)
{
        switch (id) {

        case CLOCK_REALTIME:     return ktime_get_real();
        case CLOCK_MONOTONIC: return ktime_get();
        case CLOCK_BOOTTIME:    return ktime_get_bootime();
        }
}

>>       ev.time = ktime_to_timeval(time);
>>       ev.type = EV_SYN;
>> @@ -159,7 +167,7 @@ static void __pass_event(struct evdev_client *client,
>>
>>  static void evdev_pass_values(struct evdev_client *client,
>>                       const struct input_value *vals, unsigned int count,
>> -                     ktime_t mono, ktime_t real)
>> +                     ktime_t *ev_time)
>>  {
>>       struct evdev *evdev = client->evdev;
>>       const struct input_value *v;
>> @@ -169,8 +177,9 @@ static void evdev_pass_values(struct evdev_client *client,
>>       if (client->revoked)
>>               return;
>>
>> -     event.time = ktime_to_timeval(client->clkid == CLOCK_MONOTONIC ?
>> -                                   mono : real);
>> +     event.time = ktime_to_timeval(client->clkid == CLOCK_REALTIME ?
>> +                     ev_time[REAL] : client->clkid == CLOCK_MONOTONIC ?
>> +                     ev_time[MONO] : ev_time[BOOT]);
>
> This becomes unwieldy. Should we have client->clk_type instead of
> client->clkid and convert CLOCK_* into your EVDEV_CLK_{REAL|MONO|BOOT}
> when setting it in ioctl and then do
>
>         event.time = ktime_to_timeval(ev_time[client->clk_offset]);
>

Sure, using clk_type would be better and improve code readability.

I am afraid how converting CLOCK_* into your
EVDEV_CLK_{REAL|MONO|BOOT} will help
because we cannot have ev_time array size more than CLK_MAX (3).

Did you mean to have following changes:

1. Add clk_type variable
struct evdev_client {
         int clkid:
      + int clk_type;
}

2. Add new funtion for setting clk_type to improve readability
static int set_clk_type(struct evdev_client *client, int id)
{
        switch (id) {

        case CLOCK_REALTIME:     client->clk_type = EV_REAL;  break;
        case CLOCK_MONOTONIC: client->clk_type = EV_MONO; break;
        case CLOCK_BOOTTIME:    client->clk_type = EV_BOOT;  break;
        default: return -1
        }

        return 0;
}

3. Addition in ioctl call
    case EVIOCSCLOCKID:
    ...
    if (!set_clk_type())
           return -EINVAL;

     client->clkid = i;
     return 0;

4. Change in evdev_pass_values function
event.time = ktime_to_timeval(ev_time[client->clk_type]);

>>
>>       /* Interrupts are disabled, just acquire the lock. */
>>       spin_lock(&client->buffer_lock);
>> @@ -198,21 +207,21 @@ static void evdev_events(struct input_handle *handle,
>>  {
>>       struct evdev *evdev = handle->private;
>>       struct evdev_client *client;
>> -     ktime_t time_mono, time_real;
>> +     ktime_t ev_time[CLK_MAX];
>>
>> -     time_mono = ktime_get();
>> -     time_real = ktime_mono_to_real(time_mono);
>> +     ev_time[MONO] = ktime_get();
>> +     ev_time[REAL] = ktime_mono_to_real(ev_time[MONO]);
>> +     ev_time[BOOT] = ktime_get_boottime();
>
> I do not think we want to use ktime_get_boottime() here; I'd rather you
> use ktime_mono_to_anY(ev_time[MONO], TK_OFFS_BOOT) so that all 3 times
> are consistent.
>

Sure. I will send the updated patch with this change.

>>
>>       rcu_read_lock();
>>
>>       client = rcu_dereference(evdev->grab);
>>
>>       if (client)
>> -             evdev_pass_values(client, vals, count, time_mono, time_real);
>> +             evdev_pass_values(client, vals, count, ev_time);
>>       else
>>               list_for_each_entry_rcu(client, &evdev->client_list, node)
>> -                     evdev_pass_values(client, vals, count,
>> -                                       time_mono, time_real);
>> +                     evdev_pass_values(client, vals, count, ev_time);
>>
>>       rcu_read_unlock();
>>  }
>> @@ -874,7 +883,7 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd,
>>       case EVIOCSCLOCKID:
>>               if (copy_from_user(&i, p, sizeof(unsigned int)))
>>                       return -EFAULT;
>> -             if (i != CLOCK_MONOTONIC && i != CLOCK_REALTIME)
>> +             if (i != CLOCK_MONOTONIC && i != CLOCK_REALTIME && i != CLOCK_BOOTTIME)
>>                       return -EINVAL;
>>               client->clkid = i;
>>               return 0;
>> --
>> 1.9.1
>>
>
> Thanks.
>
> --
> Dmitry

Thanks,
Aniroop Mathur
--
To unsubscribe from this list: send the line "unsubscribe linux-input" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Dmitry Torokhov Dec. 17, 2014, 10:03 p.m. UTC | #3
On Thu, Dec 18, 2014 at 03:03:26AM +0530, Aniroop Mathur wrote:
> Hello Mr. Torokhov,
> 
> On Wed, Dec 17, 2014 at 11:50 PM, Dmitry Torokhov
> <dmitry.torokhov@gmail.com> wrote:
> > Hi Aniroop,
> >
> > On Tue, Dec 16, 2014 at 10:26:34PM +0530, Aniroop Mathur wrote:
> >> This patch adds support for CLOCK_BOOTTIME for input event timestamp.
> >> CLOCK_BOOTTIME includes suspend time, so it would allow aplications
> >> to get correct time difference between two events even when system
> >> resumes from suspend state.
> >>
> >> Signed-off-by: Aniroop Mathur <a.mathur@samsung.com>
> >> ---
> >>  drivers/input/evdev.c | 33 +++++++++++++++++++++------------
> >>  1 file changed, 21 insertions(+), 12 deletions(-)
> >>
> >> diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
> >> index de05545..7825794 100644
> >> --- a/drivers/input/evdev.c
> >> +++ b/drivers/input/evdev.c
> >> @@ -28,6 +28,13 @@
> >>  #include <linux/cdev.h>
> >>  #include "input-compat.h"
> >>
> >> +enum clock_type {
> >> +     REAL = 0,
> >> +     MONO,
> >> +     BOOT,
> >> +     CLK_MAX
> >> +};
> >> +
> >>  struct evdev {
> >>       int open;
> >>       struct input_handle handle;
> >> @@ -108,8 +115,9 @@ static void evdev_queue_syn_dropped(struct evdev_client *client)
> >>       struct input_event ev;
> >>       ktime_t time;
> >>
> >> -     time = (client->clkid == CLOCK_MONOTONIC) ?
> >> -             ktime_get() : ktime_get_real();
> >> +     time = (client->clkid == CLOCK_REALTIME) ?
> >> +             ktime_get_real() : (client->clkid == CLOCK_MONOTONIC) ?
> >> +             ktime_get() : ktime_get_boottime();
> >>
> 
> Is this okay ?
> To improve readabilty,
> how about adding a new funtion to get time depending upon clkid like below ?
> time = get_clk_time(client->clkid);
> 
> static ktime_t get_clk_time(int id)
> {
>         switch (id) {
> 
>         case CLOCK_REALTIME:     return ktime_get_real();
>         case CLOCK_MONOTONIC: return ktime_get();
>         case CLOCK_BOOTTIME:    return ktime_get_bootime();
>         }
> }

Just open-code it in evdev_queue_syn_dropped() since there is only place
where we call it. And use clk_type instead of clock id-.

> 
> >>       ev.time = ktime_to_timeval(time);
> >>       ev.type = EV_SYN;
> >> @@ -159,7 +167,7 @@ static void __pass_event(struct evdev_client *client,
> >>
> >>  static void evdev_pass_values(struct evdev_client *client,
> >>                       const struct input_value *vals, unsigned int count,
> >> -                     ktime_t mono, ktime_t real)
> >> +                     ktime_t *ev_time)
> >>  {
> >>       struct evdev *evdev = client->evdev;
> >>       const struct input_value *v;
> >> @@ -169,8 +177,9 @@ static void evdev_pass_values(struct evdev_client *client,
> >>       if (client->revoked)
> >>               return;
> >>
> >> -     event.time = ktime_to_timeval(client->clkid == CLOCK_MONOTONIC ?
> >> -                                   mono : real);
> >> +     event.time = ktime_to_timeval(client->clkid == CLOCK_REALTIME ?
> >> +                     ev_time[REAL] : client->clkid == CLOCK_MONOTONIC ?
> >> +                     ev_time[MONO] : ev_time[BOOT]);
> >
> > This becomes unwieldy. Should we have client->clk_type instead of
> > client->clkid and convert CLOCK_* into your EVDEV_CLK_{REAL|MONO|BOOT}
> > when setting it in ioctl and then do
> >
> >         event.time = ktime_to_timeval(ev_time[client->clk_offset]);
> >
> 
> Sure, using clk_type would be better and improve code readability.
> 
> I am afraid how converting CLOCK_* into your
> EVDEV_CLK_{REAL|MONO|BOOT} will help
> because we cannot have ev_time array size more than CLK_MAX (3).
> 
> Did you mean to have following changes:
> 
> 1. Add clk_type variable
> struct evdev_client {
>          int clkid:
>       + int clk_type;
> }

I meant replacing clkid with clk_type in evdev_client.

> 
> 2. Add new funtion for setting clk_type to improve readability
> static int set_clk_type(struct evdev_client *client, int id)


evdev_set_clk_type() to keep with the style.

> {
>         switch (id) {
> 
>         case CLOCK_REALTIME:     client->clk_type = EV_REAL;  break;
>         case CLOCK_MONOTONIC: client->clk_type = EV_MONO; break;
>         case CLOCK_BOOTTIME:    client->clk_type = EV_BOOT;  break;
>         default: return -1

-EINVAL here, otherwise yes.

>         }
> 
>         return 0;
> }
> 
> 3. Addition in ioctl call
>     case EVIOCSCLOCKID:
>     ...
>     if (!set_clk_type())
>            return -EINVAL;
> 

	error = evdev_set_clktype(i);
	if (error)
		return error;

>      client->clkid = i;

Drop this.

>      return 0;
> 
> 4. Change in evdev_pass_values function
> event.time = ktime_to_timeval(ev_time[client->clk_type]);

Yes.

> 
> >>
> >>       /* Interrupts are disabled, just acquire the lock. */
> >>       spin_lock(&client->buffer_lock);
> >> @@ -198,21 +207,21 @@ static void evdev_events(struct input_handle *handle,
> >>  {
> >>       struct evdev *evdev = handle->private;
> >>       struct evdev_client *client;
> >> -     ktime_t time_mono, time_real;
> >> +     ktime_t ev_time[CLK_MAX];
> >>
> >> -     time_mono = ktime_get();
> >> -     time_real = ktime_mono_to_real(time_mono);
> >> +     ev_time[MONO] = ktime_get();
> >> +     ev_time[REAL] = ktime_mono_to_real(ev_time[MONO]);
> >> +     ev_time[BOOT] = ktime_get_boottime();
> >
> > I do not think we want to use ktime_get_boottime() here; I'd rather you
> > use ktime_mono_to_anY(ev_time[MONO], TK_OFFS_BOOT) so that all 3 times
> > are consistent.
> >
> 
> Sure. I will send the updated patch with this change.
> 
> >>
> >>       rcu_read_lock();
> >>
> >>       client = rcu_dereference(evdev->grab);
> >>
> >>       if (client)
> >> -             evdev_pass_values(client, vals, count, time_mono, time_real);
> >> +             evdev_pass_values(client, vals, count, ev_time);
> >>       else
> >>               list_for_each_entry_rcu(client, &evdev->client_list, node)
> >> -                     evdev_pass_values(client, vals, count,
> >> -                                       time_mono, time_real);
> >> +                     evdev_pass_values(client, vals, count, ev_time);
> >>
> >>       rcu_read_unlock();
> >>  }
> >> @@ -874,7 +883,7 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd,
> >>       case EVIOCSCLOCKID:
> >>               if (copy_from_user(&i, p, sizeof(unsigned int)))
> >>                       return -EFAULT;
> >> -             if (i != CLOCK_MONOTONIC && i != CLOCK_REALTIME)
> >> +             if (i != CLOCK_MONOTONIC && i != CLOCK_REALTIME && i != CLOCK_BOOTTIME)
> >>                       return -EINVAL;
> >>               client->clkid = i;
> >>               return 0;
> >> --
> >> 1.9.1
> >>
> >
> > Thanks.
> >
> > --
> > Dmitry
> 
> Thanks,
> Aniroop Mathur
Aniroop Mathur Dec. 17, 2014, 11:11 p.m. UTC | #4
Hello Mr. Torokhov,


On Thu, Dec 18, 2014 at 3:33 AM, Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:
> On Thu, Dec 18, 2014 at 03:03:26AM +0530, Aniroop Mathur wrote:
>> Hello Mr. Torokhov,
>>
>> On Wed, Dec 17, 2014 at 11:50 PM, Dmitry Torokhov
>> <dmitry.torokhov@gmail.com> wrote:
>> > Hi Aniroop,
>> >
>> > On Tue, Dec 16, 2014 at 10:26:34PM +0530, Aniroop Mathur wrote:
>> >> This patch adds support for CLOCK_BOOTTIME for input event timestamp.
>> >> CLOCK_BOOTTIME includes suspend time, so it would allow aplications
>> >> to get correct time difference between two events even when system
>> >> resumes from suspend state.
>> >>
>> >> Signed-off-by: Aniroop Mathur <a.mathur@samsung.com>
>> >> ---
>> >>  drivers/input/evdev.c | 33 +++++++++++++++++++++------------
>> >>  1 file changed, 21 insertions(+), 12 deletions(-)
>> >>
>> >> diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
>> >> index de05545..7825794 100644
>> >> --- a/drivers/input/evdev.c
>> >> +++ b/drivers/input/evdev.c
>> >> @@ -28,6 +28,13 @@
>> >>  #include <linux/cdev.h>
>> >>  #include "input-compat.h"
>> >>
>> >> +enum clock_type {
>> >> +     REAL = 0,
>> >> +     MONO,
>> >> +     BOOT,
>> >> +     CLK_MAX
>> >> +};
>> >> +
>> >>  struct evdev {
>> >>       int open;
>> >>       struct input_handle handle;
>> >> @@ -108,8 +115,9 @@ static void evdev_queue_syn_dropped(struct evdev_client *client)
>> >>       struct input_event ev;
>> >>       ktime_t time;
>> >>
>> >> -     time = (client->clkid == CLOCK_MONOTONIC) ?
>> >> -             ktime_get() : ktime_get_real();
>> >> +     time = (client->clkid == CLOCK_REALTIME) ?
>> >> +             ktime_get_real() : (client->clkid == CLOCK_MONOTONIC) ?
>> >> +             ktime_get() : ktime_get_boottime();
>> >>
>>
>> Is this okay ?
>> To improve readabilty,
>> how about adding a new funtion to get time depending upon clkid like below ?
>> time = get_clk_time(client->clkid);
>>
>> static ktime_t get_clk_time(int id)
>> {
>>         switch (id) {
>>
>>         case CLOCK_REALTIME:     return ktime_get_real();
>>         case CLOCK_MONOTONIC: return ktime_get();
>>         case CLOCK_BOOTTIME:    return ktime_get_bootime();
>>         }
>> }
>
> Just open-code it in evdev_queue_syn_dropped() since there is only place
> where we call it. And use clk_type instead of clock id-.
>
>>
>> >>       ev.time = ktime_to_timeval(time);
>> >>       ev.type = EV_SYN;
>> >> @@ -159,7 +167,7 @@ static void __pass_event(struct evdev_client *client,
>> >>
>> >>  static void evdev_pass_values(struct evdev_client *client,
>> >>                       const struct input_value *vals, unsigned int count,
>> >> -                     ktime_t mono, ktime_t real)
>> >> +                     ktime_t *ev_time)
>> >>  {
>> >>       struct evdev *evdev = client->evdev;
>> >>       const struct input_value *v;
>> >> @@ -169,8 +177,9 @@ static void evdev_pass_values(struct evdev_client *client,
>> >>       if (client->revoked)
>> >>               return;
>> >>
>> >> -     event.time = ktime_to_timeval(client->clkid == CLOCK_MONOTONIC ?
>> >> -                                   mono : real);
>> >> +     event.time = ktime_to_timeval(client->clkid == CLOCK_REALTIME ?
>> >> +                     ev_time[REAL] : client->clkid == CLOCK_MONOTONIC ?
>> >> +                     ev_time[MONO] : ev_time[BOOT]);
>> >
>> > This becomes unwieldy. Should we have client->clk_type instead of
>> > client->clkid and convert CLOCK_* into your EVDEV_CLK_{REAL|MONO|BOOT}
>> > when setting it in ioctl and then do
>> >
>> >         event.time = ktime_to_timeval(ev_time[client->clk_offset]);
>> >
>>
>> Sure, using clk_type would be better and improve code readability.
>>
>> I am afraid how converting CLOCK_* into your
>> EVDEV_CLK_{REAL|MONO|BOOT} will help
>> because we cannot have ev_time array size more than CLK_MAX (3).
>>
>> Did you mean to have following changes:
>>
>> 1. Add clk_type variable
>> struct evdev_client {
>>          int clkid:
>>       + int clk_type;
>> }
>
> I meant replacing clkid with clk_type in evdev_client.
>
>>
>> 2. Add new funtion for setting clk_type to improve readability
>> static int set_clk_type(struct evdev_client *client, int id)
>
>
> evdev_set_clk_type() to keep with the style.
>
>> {
>>         switch (id) {
>>
>>         case CLOCK_REALTIME:     client->clk_type = EV_REAL;  break;
>>         case CLOCK_MONOTONIC: client->clk_type = EV_MONO; break;
>>         case CLOCK_BOOTTIME:    client->clk_type = EV_BOOT;  break;
>>         default: return -1
>
> -EINVAL here, otherwise yes.
>
>>         }
>>
>>         return 0;
>> }
>>
>> 3. Addition in ioctl call
>>     case EVIOCSCLOCKID:
>>     ...
>>     if (!set_clk_type())
>>            return -EINVAL;
>>
>
>         error = evdev_set_clktype(i);
>         if (error)
>                 return error;
>
>>      client->clkid = i;
>
> Drop this.
>
>>      return 0;
>>
>> 4. Change in evdev_pass_values function
>> event.time = ktime_to_timeval(ev_time[client->clk_type]);
>
> Yes.
>
>>
>> >>
>> >>       /* Interrupts are disabled, just acquire the lock. */
>> >>       spin_lock(&client->buffer_lock);
>> >> @@ -198,21 +207,21 @@ static void evdev_events(struct input_handle *handle,
>> >>  {
>> >>       struct evdev *evdev = handle->private;
>> >>       struct evdev_client *client;
>> >> -     ktime_t time_mono, time_real;
>> >> +     ktime_t ev_time[CLK_MAX];
>> >>
>> >> -     time_mono = ktime_get();
>> >> -     time_real = ktime_mono_to_real(time_mono);
>> >> +     ev_time[MONO] = ktime_get();
>> >> +     ev_time[REAL] = ktime_mono_to_real(ev_time[MONO]);
>> >> +     ev_time[BOOT] = ktime_get_boottime();
>> >
>> > I do not think we want to use ktime_get_boottime() here; I'd rather you
>> > use ktime_mono_to_anY(ev_time[MONO], TK_OFFS_BOOT) so that all 3 times
>> > are consistent.
>> >
>>
>> Sure. I will send the updated patch with this change.
>>
>> >>
>> >>       rcu_read_lock();
>> >>
>> >>       client = rcu_dereference(evdev->grab);
>> >>
>> >>       if (client)
>> >> -             evdev_pass_values(client, vals, count, time_mono, time_real);
>> >> +             evdev_pass_values(client, vals, count, ev_time);
>> >>       else
>> >>               list_for_each_entry_rcu(client, &evdev->client_list, node)
>> >> -                     evdev_pass_values(client, vals, count,
>> >> -                                       time_mono, time_real);
>> >> +                     evdev_pass_values(client, vals, count, ev_time);
>> >>
>> >>       rcu_read_unlock();
>> >>  }
>> >> @@ -874,7 +883,7 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd,
>> >>       case EVIOCSCLOCKID:
>> >>               if (copy_from_user(&i, p, sizeof(unsigned int)))
>> >>                       return -EFAULT;
>> >> -             if (i != CLOCK_MONOTONIC && i != CLOCK_REALTIME)
>> >> +             if (i != CLOCK_MONOTONIC && i != CLOCK_REALTIME && i != CLOCK_BOOTTIME)
>> >>                       return -EINVAL;
>> >>               client->clkid = i;
>> >>               return 0;
>> >> --
>> >> 1.9.1
>> >>
>> >
>> > Thanks.
>> >
>> > --
>> > Dmitry
>>
>> Thanks,
>> Aniroop Mathur
>
> --
> Dmitry

Thanks for the suggestions !!
I have sent you the updated patch with new changes done.

Thanks,
Aniroop
--
To unsubscribe from this list: send the line "unsubscribe linux-input" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index de05545..7825794 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -28,6 +28,13 @@ 
 #include <linux/cdev.h>
 #include "input-compat.h"
 
+enum clock_type {
+	REAL = 0,
+	MONO,
+	BOOT,
+	CLK_MAX
+};
+
 struct evdev {
 	int open;
 	struct input_handle handle;
@@ -108,8 +115,9 @@  static void evdev_queue_syn_dropped(struct evdev_client *client)
 	struct input_event ev;
 	ktime_t time;
 
-	time = (client->clkid == CLOCK_MONOTONIC) ?
-		ktime_get() : ktime_get_real();
+	time = (client->clkid == CLOCK_REALTIME) ?
+		ktime_get_real() : (client->clkid == CLOCK_MONOTONIC) ?
+		ktime_get() : ktime_get_boottime();
 
 	ev.time = ktime_to_timeval(time);
 	ev.type = EV_SYN;
@@ -159,7 +167,7 @@  static void __pass_event(struct evdev_client *client,
 
 static void evdev_pass_values(struct evdev_client *client,
 			const struct input_value *vals, unsigned int count,
-			ktime_t mono, ktime_t real)
+			ktime_t *ev_time)
 {
 	struct evdev *evdev = client->evdev;
 	const struct input_value *v;
@@ -169,8 +177,9 @@  static void evdev_pass_values(struct evdev_client *client,
 	if (client->revoked)
 		return;
 
-	event.time = ktime_to_timeval(client->clkid == CLOCK_MONOTONIC ?
-				      mono : real);
+	event.time = ktime_to_timeval(client->clkid == CLOCK_REALTIME ?
+			ev_time[REAL] : client->clkid == CLOCK_MONOTONIC ?
+			ev_time[MONO] : ev_time[BOOT]);
 
 	/* Interrupts are disabled, just acquire the lock. */
 	spin_lock(&client->buffer_lock);
@@ -198,21 +207,21 @@  static void evdev_events(struct input_handle *handle,
 {
 	struct evdev *evdev = handle->private;
 	struct evdev_client *client;
-	ktime_t time_mono, time_real;
+	ktime_t ev_time[CLK_MAX];
 
-	time_mono = ktime_get();
-	time_real = ktime_mono_to_real(time_mono);
+	ev_time[MONO] = ktime_get();
+	ev_time[REAL] = ktime_mono_to_real(ev_time[MONO]);
+	ev_time[BOOT] = ktime_get_boottime();
 
 	rcu_read_lock();
 
 	client = rcu_dereference(evdev->grab);
 
 	if (client)
-		evdev_pass_values(client, vals, count, time_mono, time_real);
+		evdev_pass_values(client, vals, count, ev_time);
 	else
 		list_for_each_entry_rcu(client, &evdev->client_list, node)
-			evdev_pass_values(client, vals, count,
-					  time_mono, time_real);
+			evdev_pass_values(client, vals, count, ev_time);
 
 	rcu_read_unlock();
 }
@@ -874,7 +883,7 @@  static long evdev_do_ioctl(struct file *file, unsigned int cmd,
 	case EVIOCSCLOCKID:
 		if (copy_from_user(&i, p, sizeof(unsigned int)))
 			return -EFAULT;
-		if (i != CLOCK_MONOTONIC && i != CLOCK_REALTIME)
+		if (i != CLOCK_MONOTONIC && i != CLOCK_REALTIME && i != CLOCK_BOOTTIME)
 			return -EINVAL;
 		client->clkid = i;
 		return 0;