RE: [PATCH] i2c: designware: Enable ioctl I2C_TIMEOUT

From: Voon, Weifeng
Date: Thu Jun 02 2016 - 05:11:15 EST

> From: Uwe Kleine-König [mailto:u.kleine-koenig@xxxxxxxxxxxxxx]
> On Thu, Jun 02, 2016 at 03:57:30PM +0800, Weifeng Voon wrote:
> > This allows applications to set the transfer timeout in 10ms
> > increments via ioctl I2C_TIMEOUT.
> 10ms is only correct with HZ=100. With higher values of HZ you get a finer
> resolution. I'd write:
> Respect the transfer timeout set via the I2C_TIMEOUT ioctl.

10ms is correct and regardless of HZ.
>From i2c-dev.c:
client->adapter->timeout = msecs_to_jiffies(arg * 10);

The purpose of putting in the resolution of 10ms is just for the ease of others when
they are using this patch. I am ok to take it out if it is not necessary.

> and not mention the resolution at all. After all your patch doesn't "enable" that
> ioctl, just makes use of the value set by it.

Yes, you are right. I am just using the value set by it. Maybe this may sounds more
Set transfer timeout via ioctl I2C_TIMEOUT

Or any other recommendation?

> Best regards
> Uwe
> --
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