* [PATCH v2] i2c: npcm7xx: bug fix timeout (usec instead of msec)
@ 2020-08-30 12:20 Tali Perry
2020-08-30 12:47 ` Avi Fishman
2020-08-30 18:01 ` Andy Shevchenko
0 siblings, 2 replies; 5+ messages in thread
From: Tali Perry @ 2020-08-30 12:20 UTC (permalink / raw)
To: kunyi, xqiu, benjaminfair, avifishman70, joel, tmaimon77, wsa
Cc: linux-i2c, openbmc, linux-kernel, Tali Perry
i2c: npcm7xx: bug fix timeout (usec instead of msec)
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
---
drivers/i2c/busses/i2c-npcm7xx.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 75f07138a6fa..abb334492a3d 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -2093,8 +2093,13 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
}
}
- /* Adaptive TimeOut: astimated time in usec + 100% margin */
- timeout_usec = (2 * 10000 / bus->bus_freq) * (2 + nread + nwrite);
+ /*
+ * Adaptive TimeOut: estimated time in usec + 100% margin:
+ * 2: double the timeout for clock stretching case
+ * 9: bits per transaction (including the ack/nack)
+ * 1000000: micro second in a second
+ */
+ timeout_usec = (2 * 9 * 1000000 / bus->bus_freq) * (2 + nread + nwrite);
timeout = max(msecs_to_jiffies(35), usecs_to_jiffies(timeout_usec));
if (nwrite >= 32 * 1024 || nread >= 32 * 1024) {
dev_err(bus->dev, "i2c%d buffer too big\n", bus->num);
base-commit: d012a7190fc1fd72ed48911e77ca97ba4521bccd
--
2.22.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH v2] i2c: npcm7xx: bug fix timeout (usec instead of msec)
2020-08-30 12:20 [PATCH v2] i2c: npcm7xx: bug fix timeout (usec instead of msec) Tali Perry
@ 2020-08-30 12:47 ` Avi Fishman
2020-08-30 18:01 ` Andy Shevchenko
1 sibling, 0 replies; 5+ messages in thread
From: Avi Fishman @ 2020-08-30 12:47 UTC (permalink / raw)
To: Tali Perry
Cc: kunyi, xqiu, Benjamin Fair, Joel Stanley, Tomer Maimon, wsa,
linux-i2c, OpenBMC Maillist, Linux Kernel Mailing List
On Sun, Aug 30, 2020 at 3:21 PM Tali Perry <tali.perry1@gmail.com> wrote:
>
> i2c: npcm7xx: bug fix timeout (usec instead of msec)
>
> Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Reviewed-by: Avi Fishman <avifishman70@gmail.com>
> ---
> drivers/i2c/busses/i2c-npcm7xx.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
> index 75f07138a6fa..abb334492a3d 100644
> --- a/drivers/i2c/busses/i2c-npcm7xx.c
> +++ b/drivers/i2c/busses/i2c-npcm7xx.c
> @@ -2093,8 +2093,13 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
> }
> }
>
> - /* Adaptive TimeOut: astimated time in usec + 100% margin */
> - timeout_usec = (2 * 10000 / bus->bus_freq) * (2 + nread + nwrite);
> + /*
> + * Adaptive TimeOut: estimated time in usec + 100% margin:
> + * 2: double the timeout for clock stretching case
> + * 9: bits per transaction (including the ack/nack)
> + * 1000000: micro second in a second
> + */
> + timeout_usec = (2 * 9 * 1000000 / bus->bus_freq) * (2 + nread + nwrite);
> timeout = max(msecs_to_jiffies(35), usecs_to_jiffies(timeout_usec));
> if (nwrite >= 32 * 1024 || nread >= 32 * 1024) {
> dev_err(bus->dev, "i2c%d buffer too big\n", bus->num);
>
> base-commit: d012a7190fc1fd72ed48911e77ca97ba4521bccd
> --
> 2.22.0
>
--
Regards,
Avi
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v2] i2c: npcm7xx: bug fix timeout (usec instead of msec)
2020-08-30 12:20 [PATCH v2] i2c: npcm7xx: bug fix timeout (usec instead of msec) Tali Perry
2020-08-30 12:47 ` Avi Fishman
@ 2020-08-30 18:01 ` Andy Shevchenko
2020-08-31 7:57 ` Avi Fishman
1 sibling, 1 reply; 5+ messages in thread
From: Andy Shevchenko @ 2020-08-30 18:01 UTC (permalink / raw)
To: Tali Perry
Cc: kunyi, xqiu, benjaminfair, Avi Fishman, Joel Stanley,
Tomer Maimon, Wolfram Sang, linux-i2c, OpenBMC Maillist,
Linux Kernel Mailing List
On Sun, Aug 30, 2020 at 3:23 PM Tali Perry <tali.perry1@gmail.com> wrote:
>
> i2c: npcm7xx: bug fix timeout (usec instead of msec)
This commit message is awful. Please read [1] as a tutorial how to
write a commit messages.
[1]: https://chris.beams.io/posts/git-commit/
...
> - /* Adaptive TimeOut: astimated time in usec + 100% margin */
> - timeout_usec = (2 * 10000 / bus->bus_freq) * (2 + nread + nwrite);
> + /*
> + * Adaptive TimeOut: estimated time in usec + 100% margin:
> + * 2: double the timeout for clock stretching case
> + * 9: bits per transaction (including the ack/nack)
> + * 1000000: micro second in a second
No need. See below.
> + */
> + timeout_usec = (2 * 9 * 1000000 / bus->bus_freq) * (2 + nread + nwrite);
USEC_PER_SEC
> timeout = max(msecs_to_jiffies(35), usecs_to_jiffies(timeout_usec));
> if (nwrite >= 32 * 1024 || nread >= 32 * 1024) {
> dev_err(bus->dev, "i2c%d buffer too big\n", bus->num);
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v2] i2c: npcm7xx: bug fix timeout (usec instead of msec)
2020-08-30 18:01 ` Andy Shevchenko
@ 2020-08-31 7:57 ` Avi Fishman
2020-08-31 12:03 ` Avi Fishman
0 siblings, 1 reply; 5+ messages in thread
From: Avi Fishman @ 2020-08-31 7:57 UTC (permalink / raw)
To: Andy Shevchenko
Cc: Tali Perry, kunyi, xqiu, Benjamin Fair, Joel Stanley,
Tomer Maimon, Wolfram Sang, linux-i2c, OpenBMC Maillist,
Linux Kernel Mailing List
On Sun, Aug 30, 2020 at 9:01 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>
> On Sun, Aug 30, 2020 at 3:23 PM Tali Perry <tali.perry1@gmail.com> wrote:
>
> >
> > i2c: npcm7xx: bug fix timeout (usec instead of msec)
>
> This commit message is awful. Please read [1] as a tutorial how to
> write a commit messages.
>
Would this be better:
i2c: npcm7xx: Fix microsecond timeout calculation
Inside npcm_i2c_master_xfer() we calculate a timeout for the entire
transaction in microseconds, the calculation was wrong so big i2c
massages would timeout before they ended.
This commit fix that.
> [1]: https://chris.beams.io/posts/git-commit/
>
> ...
>
> > - /* Adaptive TimeOut: astimated time in usec + 100% margin */
> > - timeout_usec = (2 * 10000 / bus->bus_freq) * (2 + nread + nwrite);
> > + /*
> > + * Adaptive TimeOut: estimated time in usec + 100% margin:
> > + * 2: double the timeout for clock stretching case
> > + * 9: bits per transaction (including the ack/nack)
>
> > + * 1000000: micro second in a second
>
> No need. See below.
>
> > + */
>
> > + timeout_usec = (2 * 9 * 1000000 / bus->bus_freq) * (2 + nread + nwrite);
>
> USEC_PER_SEC
OK
>
> > timeout = max(msecs_to_jiffies(35), usecs_to_jiffies(timeout_usec));
> > if (nwrite >= 32 * 1024 || nread >= 32 * 1024) {
> > dev_err(bus->dev, "i2c%d buffer too big\n", bus->num);
>
> --
> With Best Regards,
> Andy Shevchenko
--
Regards,
Avi
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v2] i2c: npcm7xx: bug fix timeout (usec instead of msec)
2020-08-31 7:57 ` Avi Fishman
@ 2020-08-31 12:03 ` Avi Fishman
0 siblings, 0 replies; 5+ messages in thread
From: Avi Fishman @ 2020-08-31 12:03 UTC (permalink / raw)
To: Andy Shevchenko
Cc: Tali Perry, kunyi, xqiu, Benjamin Fair, Joel Stanley,
Tomer Maimon, Wolfram Sang, linux-i2c, OpenBMC Maillist,
Linux Kernel Mailing List
Please ignore my last mail, Tali already sent v3.
On Mon, Aug 31, 2020 at 10:57 AM Avi Fishman <avifishman70@gmail.com> wrote:
>
> On Sun, Aug 30, 2020 at 9:01 PM Andy Shevchenko
> <andy.shevchenko@gmail.com> wrote:
> >
> > On Sun, Aug 30, 2020 at 3:23 PM Tali Perry <tali.perry1@gmail.com> wrote:
> >
> > >
> > > i2c: npcm7xx: bug fix timeout (usec instead of msec)
> >
> > This commit message is awful. Please read [1] as a tutorial how to
> > write a commit messages.
> >
>
> Would this be better:
> i2c: npcm7xx: Fix microsecond timeout calculation
>
> Inside npcm_i2c_master_xfer() we calculate a timeout for the entire
> transaction in microseconds, the calculation was wrong so big i2c
> massages would timeout before they ended.
> This commit fix that.
>
> > [1]: https://chris.beams.io/posts/git-commit/
> >
> > ...
> >
> > > - /* Adaptive TimeOut: astimated time in usec + 100% margin */
> > > - timeout_usec = (2 * 10000 / bus->bus_freq) * (2 + nread + nwrite);
> > > + /*
> > > + * Adaptive TimeOut: estimated time in usec + 100% margin:
> > > + * 2: double the timeout for clock stretching case
> > > + * 9: bits per transaction (including the ack/nack)
> >
> > > + * 1000000: micro second in a second
> >
> > No need. See below.
> >
> > > + */
> >
> > > + timeout_usec = (2 * 9 * 1000000 / bus->bus_freq) * (2 + nread + nwrite);
> >
> > USEC_PER_SEC
>
> OK
>
> >
> > > timeout = max(msecs_to_jiffies(35), usecs_to_jiffies(timeout_usec));
> > > if (nwrite >= 32 * 1024 || nread >= 32 * 1024) {
> > > dev_err(bus->dev, "i2c%d buffer too big\n", bus->num);
> >
> > --
> > With Best Regards,
> > Andy Shevchenko
>
>
>
> --
> Regards,
> Avi
--
Regards,
Avi
^ permalink raw reply [flat|nested] 5+ messages in thread
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2020-08-30 12:20 [PATCH v2] i2c: npcm7xx: bug fix timeout (usec instead of msec) Tali Perry
2020-08-30 12:47 ` Avi Fishman
2020-08-30 18:01 ` Andy Shevchenko
2020-08-31 7:57 ` Avi Fishman
2020-08-31 12:03 ` Avi Fishman
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