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[PATCH v1] mfd: max77705: support revision 0x2

Eric Gonçalves posted 1 patch 2 months ago 
drivers/mfd/max77705.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
[PATCH v1] mfd: max77705: support revision 0x2
Posted by Eric Gonçalves 2 months ago 
Revision 0x2 has been tested on the r0q (Galaxy S22) board.

Signed-off-by: Eric Gonçalves <ghatto404@gmail.com>
---
 drivers/mfd/max77705.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/mfd/max77705.c b/drivers/mfd/max77705.c
index e1a9bfd65856..5201a4c9c3f5 100644
--- a/drivers/mfd/max77705.c
+++ b/drivers/mfd/max77705.c
@@ -105,8 +105,8 @@ static int max77705_i2c_probe(struct i2c_client *i2c)
 		return -ENODEV;
 
 	pmic_rev = pmic_rev_value & MAX77705_REVISION_MASK;
-	if (pmic_rev != MAX77705_PASS3)
-		return dev_err_probe(dev, -ENODEV, "Rev.0x%x is not tested\n", pmic_rev);
+	if (pmic_rev == MAX77705_PASS1)
+		return dev_err_probe(dev, -ENODEV, "Rev.0x1 is not tested\n");
 
 	/* Active Discharge Enable */
 	regmap_update_bits(max77705->regmap, MAX77705_PMIC_REG_MAINCTRL1, 1, 1);
-- 
2.51.0
Re: [PATCH v1] mfd: max77705: support revision 0x2
Posted by Lee Jones 1 month, 3 weeks ago 
On Tue, 14 Oct 2025, Eric Gonçalves wrote:

> Revision 0x2 has been tested on the r0q (Galaxy S22) board.
> 
> Signed-off-by: Eric Gonçalves <ghatto404@gmail.com>
> ---
>  drivers/mfd/max77705.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/mfd/max77705.c b/drivers/mfd/max77705.c
> index e1a9bfd65856..5201a4c9c3f5 100644
> --- a/drivers/mfd/max77705.c
> +++ b/drivers/mfd/max77705.c
> @@ -105,8 +105,8 @@ static int max77705_i2c_probe(struct i2c_client *i2c)
>  		return -ENODEV;
>  
>  	pmic_rev = pmic_rev_value & MAX77705_REVISION_MASK;
> -	if (pmic_rev != MAX77705_PASS3)
> -		return dev_err_probe(dev, -ENODEV, "Rev.0x%x is not tested\n", pmic_rev);
> +	if (pmic_rev == MAX77705_PASS1)
> +		return dev_err_probe(dev, -ENODEV, "Rev.0x1 is not tested\n");

What happens when PASS4 is released but not tested?

What about changing only the first line to:

  if (pmic_rev < MAX77705_PASS2 || pmic_rev > MAX77705_PASS3)

>  	/* Active Discharge Enable */
>  	regmap_update_bits(max77705->regmap, MAX77705_PMIC_REG_MAINCTRL1, 1, 1);
> -- 
> 2.51.0
> 

-- 
Lee Jones [李琼斯]
Re: [PATCH v1] mfd: max77705: support revision 0x2
Posted by Ghatto 1 month, 3 weeks ago 
On Thu, Oct 23, 2025 at 10:17 AM Lee Jones <lee@kernel.org> wrote:
>
> On Tue, 14 Oct 2025, Eric Gonçalves wrote:
>
> > Revision 0x2 has been tested on the r0q (Galaxy S22) board.
> >
> > Signed-off-by: Eric Gonçalves <ghatto404@gmail.com>
> > ---
> >  drivers/mfd/max77705.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/mfd/max77705.c b/drivers/mfd/max77705.c
> > index e1a9bfd65856..5201a4c9c3f5 100644
> > --- a/drivers/mfd/max77705.c
> > +++ b/drivers/mfd/max77705.c
> > @@ -105,8 +105,8 @@ static int max77705_i2c_probe(struct i2c_client *i2c)
> >               return -ENODEV;
> >
> >       pmic_rev = pmic_rev_value & MAX77705_REVISION_MASK;
> > -     if (pmic_rev != MAX77705_PASS3)
> > -             return dev_err_probe(dev, -ENODEV, "Rev.0x%x is not tested\n", pmic_rev);
> > +     if (pmic_rev == MAX77705_PASS1)
> > +             return dev_err_probe(dev, -ENODEV, "Rev.0x1 is not tested\n");
>
> What happens when PASS4 is released but not tested?
PASS4 doesn't exist from what I've seen on the max77705 header files.
>
> What about changing only the first line to:
>
>   if (pmic_rev < MAX77705_PASS2 || pmic_rev > MAX77705_PASS3)
>
> >       /* Active Discharge Enable */
> >       regmap_update_bits(max77705->regmap, MAX77705_PMIC_REG_MAINCTRL1, 1, 1);
> > --
> > 2.51.0
> >
>
> --
> Lee Jones [李琼斯]
Re: [PATCH v1] mfd: max77705: support revision 0x2
Posted by Lee Jones 1 month, 3 weeks ago 
On Thu, 23 Oct 2025, Ghatto wrote:

> On Thu, Oct 23, 2025 at 10:17 AM Lee Jones <lee@kernel.org> wrote:
> >
> > On Tue, 14 Oct 2025, Eric Gonçalves wrote:
> >
> > > Revision 0x2 has been tested on the r0q (Galaxy S22) board.
> > >
> > > Signed-off-by: Eric Gonçalves <ghatto404@gmail.com>
> > > ---
> > >  drivers/mfd/max77705.c | 4 ++--
> > >  1 file changed, 2 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/mfd/max77705.c b/drivers/mfd/max77705.c
> > > index e1a9bfd65856..5201a4c9c3f5 100644
> > > --- a/drivers/mfd/max77705.c
> > > +++ b/drivers/mfd/max77705.c
> > > @@ -105,8 +105,8 @@ static int max77705_i2c_probe(struct i2c_client *i2c)
> > >               return -ENODEV;
> > >
> > >       pmic_rev = pmic_rev_value & MAX77705_REVISION_MASK;
> > > -     if (pmic_rev != MAX77705_PASS3)
> > > -             return dev_err_probe(dev, -ENODEV, "Rev.0x%x is not tested\n", pmic_rev);
> > > +     if (pmic_rev == MAX77705_PASS1)
> > > +             return dev_err_probe(dev, -ENODEV, "Rev.0x1 is not tested\n");
> >
> > What happens when PASS4 is released but not tested?
> PASS4 doesn't exist from what I've seen on the max77705 header files.

Not yet.

But not having it in the defined does not mean one won't exist in the future.

-- 
Lee Jones [李琼斯]
Re: [PATCH v1] mfd: max77705: support revision 0x2
Posted by Eric Gonçalves 1 month, 3 weeks ago 

On October 23, 2025 11:21:44 AM GMT-03:00, Lee Jones <lee@kernel.org> wrote:
>On Thu, 23 Oct 2025, Ghatto wrote:
>
>> On Thu, Oct 23, 2025 at 10:17 AM Lee Jones <lee@kernel.org> wrote:
>> >
>> > On Tue, 14 Oct 2025, Eric Gonçalves wrote:
>> >
>> > > Revision 0x2 has been tested on the r0q (Galaxy S22) board.
>> > >
>> > > Signed-off-by: Eric Gonçalves <ghatto404@gmail.com>
>> > > ---
>> > >  drivers/mfd/max77705.c | 4 ++--
>> > >  1 file changed, 2 insertions(+), 2 deletions(-)
>> > >
>> > > diff --git a/drivers/mfd/max77705.c b/drivers/mfd/max77705.c
>> > > index e1a9bfd65856..5201a4c9c3f5 100644
>> > > --- a/drivers/mfd/max77705.c
>> > > +++ b/drivers/mfd/max77705.c
>> > > @@ -105,8 +105,8 @@ static int max77705_i2c_probe(struct i2c_client *i2c)
>> > >               return -ENODEV;
>> > >
>> > >       pmic_rev = pmic_rev_value & MAX77705_REVISION_MASK;
>> > > -     if (pmic_rev != MAX77705_PASS3)
>> > > -             return dev_err_probe(dev, -ENODEV, "Rev.0x%x is not tested\n", pmic_rev);
>> > > +     if (pmic_rev == MAX77705_PASS1)
>> > > +             return dev_err_probe(dev, -ENODEV, "Rev.0x1 is not tested\n");
>> >
>> > What happens when PASS4 is released but not tested?
>> PASS4 doesn't exist from what I've seen on the max77705 header files.
>
>Not yet.
>
>But not having it in the defined does not mean one won't exist in the future.
I don't think it will, newer Samsungs already use a new maxim controller.
>
Re: [PATCH v1] mfd: max77705: support revision 0x2
Posted by Lee Jones 1 month, 1 week ago 
On Thu, 23 Oct 2025, Eric Gonçalves wrote:

> 
> 
> On October 23, 2025 11:21:44 AM GMT-03:00, Lee Jones <lee@kernel.org> wrote:
> >On Thu, 23 Oct 2025, Ghatto wrote:
> >
> >> On Thu, Oct 23, 2025 at 10:17 AM Lee Jones <lee@kernel.org> wrote:
> >> >
> >> > On Tue, 14 Oct 2025, Eric Gonçalves wrote:
> >> >
> >> > > Revision 0x2 has been tested on the r0q (Galaxy S22) board.
> >> > >
> >> > > Signed-off-by: Eric Gonçalves <ghatto404@gmail.com>
> >> > > ---
> >> > >  drivers/mfd/max77705.c | 4 ++--
> >> > >  1 file changed, 2 insertions(+), 2 deletions(-)
> >> > >
> >> > > diff --git a/drivers/mfd/max77705.c b/drivers/mfd/max77705.c
> >> > > index e1a9bfd65856..5201a4c9c3f5 100644
> >> > > --- a/drivers/mfd/max77705.c
> >> > > +++ b/drivers/mfd/max77705.c
> >> > > @@ -105,8 +105,8 @@ static int max77705_i2c_probe(struct i2c_client *i2c)
> >> > >               return -ENODEV;
> >> > >
> >> > >       pmic_rev = pmic_rev_value & MAX77705_REVISION_MASK;
> >> > > -     if (pmic_rev != MAX77705_PASS3)
> >> > > -             return dev_err_probe(dev, -ENODEV, "Rev.0x%x is not tested\n", pmic_rev);
> >> > > +     if (pmic_rev == MAX77705_PASS1)
> >> > > +             return dev_err_probe(dev, -ENODEV, "Rev.0x1 is not tested\n");
> >> >
> >> > What happens when PASS4 is released but not tested?
> >> PASS4 doesn't exist from what I've seen on the max77705 header files.
> >
> >Not yet.
> >
> >But not having it in the defined does not mean one won't exist in the future.
> I don't think it will, newer Samsungs already use a new maxim controller.

Stranger things have happened.  Let's take the 'better to be safe than
sorry' approach and future-proof this the best we can.  Let's do a
proper bounds check for supported devices instead please.

-- 
Lee Jones [李琼斯]

Patchew 2.1-devel-b67e4c2

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