On Tue, Jul 30, 2024 at 10:42:01AM +0200, Krzysztof Kozlowski wrote:
> On 30/07/2024 10:24, Sakari Ailus wrote:
> > Hi Krzysztof,
> >
> > On Mon, Jul 29, 2024 at 04:09:39PM +0200, Krzysztof Kozlowski wrote:
> >> On 29/07/2024 13:04, Umang Jain wrote:
> >>> Rectify the logical value of reset-gpio so that it is set to
> >>> 0 (disabled) during power-on and to 1 (enabled) during power-off.
> >>>
> >>> Meanwhile at it, set the reset-gpio to GPIO_OUT_HIGH at initialization
> >>> time to make sure it starts off in reset.
> >>>
> >>> Fixes: 45d19b5fb9ae ("media: i2c: Add imx335 camera sensor driver")
> >>> Signed-off-by: Umang Jain <umang.jain@xxxxxxxxxxxxxxxx>
> >>> ---
> >>> drivers/media/i2c/imx335.c | 8 ++++----
> >>> 1 file changed, 4 insertions(+), 4 deletions(-)
> >>>
> >>
> >> This will break all the users, so no. At least not without mentioning
> >> ABI break and some sort of investigating how customers or users are
> >> affected.
> >
> > I know the original authors aren't using the driver anymore and it took
> > quite a bit of time until others started to contribute to it so I suspect
> > the driver hasn't been in use for that long. There are no instances of the
> > device in the in-kernel DTS either.
> >
> > Any DTS author should have also noticed the issue but of course there's a
> > risk someone could have just changed the polarity and not bothered to chech
> > what it was supposed to be.
> >
> > I agree the commit message should be more vocal about the effects on
> > existing DTS.
>
> I can imagine that all users (out of tree, in this case) inverted
> polarity in DTS based on what's implemented. You could go with some
> trivial hack, like I did for one of codecs - see 738455858a2d ("ASoC:
> codecs: wsa881x: Use proper shutdown GPIO polarity"), but I remember
> Mark Brown rejected similar commit for newer drivers.
I don't think there's any out-of-tree user, because when we started
using the recently driver, it required lots of fixes to even work at
all. I'll let Kieran and Umang comment on that, I haven't follow the
development in details.
--
Regards,
Laurent Pinchart
