On Tue, Jan 23, 2024 at 06:38:00PM +0000, Biju Das wrote:
> Hi Laurent Pinchart,
>
> Thanks for the feedback.
>
> > -----Original Message-----
> > From: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> > Sent: Tuesday, January 23, 2024 3:30 PM
> > Subject: Re: [PATCH 2/4] media: platform: rzg2l-cru: rzg2l-ip: Add delay
> > after D-PHY reset
> >
> > Hi Biju,
> >
> > Thank you for the patch.
> >
> > On Tue, Jan 23, 2024 at 11:58:19AM +0000, Biju Das wrote:
> > > As per section 35.3.1 Starting Reception for the MIPI CSI-2 Input on
> > > the latest hardware manual(R01UH0914EJ0140 Rev.1.40) it is mentioned
> > > that after DPHY reset, we need to wait for 1 msec or more before start
> > > receiving data from the sensor. So add a delay after pre_streamon().
> > >
> > > Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> > > ---
> > > drivers/media/platform/renesas/rzg2l-cru/rzg2l-ip.c | 3 +++
> > > 1 file changed, 3 insertions(+)
> > >
> > > diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-ip.c
> > > b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-ip.c
> > > index 9f351a05893e..5468dc179de7 100644
> > > --- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-ip.c
> > > +++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-ip.c
> > > @@ -5,6 +5,7 @@
> > > * Copyright (C) 2022 Renesas Electronics Corp.
> > > */
> > >
> > > +#include <linux/delay.h>
> > > #include "rzg2l-cru.h"
> > >
> > > struct rzg2l_cru_ip_format {
> > > @@ -71,6 +72,8 @@ static int rzg2l_cru_ip_s_stream(struct v4l2_subdev
> > *sd, int enable)
> > > if (ret)
> > > return ret;
> > >
> > > + usleep_range(1000, 2000);
> > > +
> >
> > What would you think of using
> >
> > fsleep(1000);
> >
> > instead ?
>
> Essentially it is same by looking at the code[1].
> OK will use fsleep()
Yes, it will result in the same delay. fsleep() is recommended as the
default sleep function unless there's a specific need to do something
different.
> [1]
> static inline void fsleep(unsigned long usecs)
> {
> if (usecs <= 10)
> udelay(usecs);
> else if (usecs <= 20000)
> usleep_range(usecs, 2 * usecs);
> else
> msleep(DIV_ROUND_UP(usecs, 1000));
> }
>
> > With or without that,
> >
> > Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
> >
> > > ret = rzg2l_cru_start_image_processing(cru);
> > > if (ret) {
> > > v4l2_subdev_call(cru->ip.remote, video, post_streamoff);
--
Regards,
Laurent Pinchart
