Re: [PATCH v4 2/7] scsi: ufs-qcom: Add reset control support for host controller

[Can Guo]

On 2019-11-14 17:03, Avri Altman wrote:
> Hi,
>
> > Add reset control for host controller so that host controller can be 
> > reset as
> > required in its power up sequence.
> >
> > Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
> > +       ret = reset_control_assert(host->core_reset);
> > +       if (ret) {
> > +               dev_err(hba->dev, "%s: core_reset assert failed, err = 
> > %d\n",
> > +                                __func__, ret);
> > +               goto out;
> > +       }
> > +
> > +       /*
> > +        * The hardware requirement for delay between assert/deassert
> > +        * is at least 3-4 sleep clock (32.7KHz) cycles, which comes 
> > to
> > +        * ~125us (4/32768). To be on the safe side add 200us delay.
> > +        */
> > +       usleep_range(200, 210);
> Aren't you sleeping anyway in your reset_control_ops?

For our cases, reset_control_assert uses the reset_control_ops->assert() 
we registered for
node &clock_gcc. There is no sleep or delay in Q's 
reset_control_ops->assert() func.

> > +
> > +       ret = reset_control_deassert(host->core_reset);
> > +       if (ret)
> > +               dev_err(hba->dev, "%s: core_reset deassert failed, err 
> > = %d\n",
> > +                                __func__, ret);
> > +
> > +       usleep_range(1000, 1100);
> ditto

Same as above.

Best Regards,
Can Guo.