[PATCH v1 1/2] of: property: Add device link support for multiple DT bindings

[PATCH v1 1/2] of: property: Add device link support for multiple DT bindings

[Saravana Kannan]

Add support for creating device links out of the following DT bindings:
- interrupts-extended
- nvmem-cells
- phys
- wakeup-parent

Signed-off-by: Saravana Kannan <saravanak@google.com>
---
 drivers/of/property.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/of/property.c b/drivers/of/property.c
index 6a5760f0d6cd..b06edeb1f88b 100644
--- a/drivers/of/property.c
+++ b/drivers/of/property.c
@@ -1269,6 +1269,11 @@ DEFINE_SIMPLE_PROP(dmas, "dmas", "#dma-cells")
 DEFINE_SIMPLE_PROP(power_domains, "power-domains", "#power-domain-cells")
 DEFINE_SIMPLE_PROP(hwlocks, "hwlocks", "#hwlock-cells")
 DEFINE_SIMPLE_PROP(extcon, "extcon", NULL)
+DEFINE_SIMPLE_PROP(interrupts_extended, "interrupts-extended",
+					"#interrupt-cells")
+DEFINE_SIMPLE_PROP(nvmem_cells, "nvmem-cells", NULL)
+DEFINE_SIMPLE_PROP(phys, "phys", "#phy-cells")
+DEFINE_SIMPLE_PROP(wakeup_parent, "wakeup-parent", NULL)
 DEFINE_SUFFIX_PROP(regulators, "-supply", NULL)
 DEFINE_SUFFIX_PROP(gpio, "-gpio", "#gpio-cells")
 DEFINE_SUFFIX_PROP(gpios, "-gpios", "#gpio-cells")
@@ -1294,6 +1299,10 @@ static const struct supplier_bindings of_supplier_bindings[] = {
 	{ .parse_prop = parse_power_domains, },
 	{ .parse_prop = parse_hwlocks, },
 	{ .parse_prop = parse_extcon, },
+	{ .parse_prop = parse_interrupts_extended, },
+	{ .parse_prop = parse_nvmem_cells, },
+	{ .parse_prop = parse_phys, },
+	{ .parse_prop = parse_wakeup_parent, },
 	{ .parse_prop = parse_regulators, },
 	{ .parse_prop = parse_gpio, },
 	{ .parse_prop = parse_gpios, },
-- 
2.28.0.rc0.105.gf9edc3c819-goog

[PATCH v1 2/2] of: property: Add device link support for pinctrl-0 through pinctrl-8

[Saravana Kannan]

Add support for pinctrl-0 through pinctrl-8 explicitly instead of trying
to add support for pinctrl-%d properties.

Of all the pinctrl-* properties in dts files (20322), only 47% (9531)
are pinctrl-%d properties. Of all the pinctrl-%d properties, 99.5%
(9486) are made up of pinctrl-[0-2].

Trying to parse all pinctrl-* properties and checking for pinctrl-%d is
unnecessarily complicated. So, just add support for pinctrl-[0-8] for
now. In the unlikely event we ever exceed pinctrl-8, we can come back
and improve this.

Signed-off-by: Saravana Kannan <saravanak@google.com>
---
 drivers/of/property.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/of/property.c b/drivers/of/property.c
index b06edeb1f88b..d40d923ffeaf 100644
--- a/drivers/of/property.c
+++ b/drivers/of/property.c
@@ -1274,6 +1274,15 @@ DEFINE_SIMPLE_PROP(interrupts_extended, "interrupts-extended",
 DEFINE_SIMPLE_PROP(nvmem_cells, "nvmem-cells", NULL)
 DEFINE_SIMPLE_PROP(phys, "phys", "#phy-cells")
 DEFINE_SIMPLE_PROP(wakeup_parent, "wakeup-parent", NULL)
+DEFINE_SIMPLE_PROP(pinctrl0, "pinctrl-0", NULL)
+DEFINE_SIMPLE_PROP(pinctrl1, "pinctrl-1", NULL)
+DEFINE_SIMPLE_PROP(pinctrl2, "pinctrl-2", NULL)
+DEFINE_SIMPLE_PROP(pinctrl3, "pinctrl-3", NULL)
+DEFINE_SIMPLE_PROP(pinctrl4, "pinctrl-4", NULL)
+DEFINE_SIMPLE_PROP(pinctrl5, "pinctrl-5", NULL)
+DEFINE_SIMPLE_PROP(pinctrl6, "pinctrl-6", NULL)
+DEFINE_SIMPLE_PROP(pinctrl7, "pinctrl-7", NULL)
+DEFINE_SIMPLE_PROP(pinctrl8, "pinctrl-8", NULL)
 DEFINE_SUFFIX_PROP(regulators, "-supply", NULL)
 DEFINE_SUFFIX_PROP(gpio, "-gpio", "#gpio-cells")
 DEFINE_SUFFIX_PROP(gpios, "-gpios", "#gpio-cells")
@@ -1303,6 +1312,15 @@ static const struct supplier_bindings of_supplier_bindings[] = {
 	{ .parse_prop = parse_nvmem_cells, },
 	{ .parse_prop = parse_phys, },
 	{ .parse_prop = parse_wakeup_parent, },
+	{ .parse_prop = parse_pinctrl0, },
+	{ .parse_prop = parse_pinctrl1, },
+	{ .parse_prop = parse_pinctrl2, },
+	{ .parse_prop = parse_pinctrl3, },
+	{ .parse_prop = parse_pinctrl4, },
+	{ .parse_prop = parse_pinctrl5, },
+	{ .parse_prop = parse_pinctrl6, },
+	{ .parse_prop = parse_pinctrl7, },
+	{ .parse_prop = parse_pinctrl8, },
 	{ .parse_prop = parse_regulators, },
 	{ .parse_prop = parse_gpio, },
 	{ .parse_prop = parse_gpios, },
-- 
2.28.0.rc0.105.gf9edc3c819-goog

Re: [PATCH v1 2/2] of: property: Add device link support for pinctrl-0 through pinctrl-8

[Frank Rowand]

On 2020-07-22 15:13, Saravana Kannan wrote:
> Add support for pinctrl-0 through pinctrl-8 explicitly instead of trying
> to add support for pinctrl-%d properties.
> 
> Of all the pinctrl-* properties in dts files (20322), only 47% (9531)
> are pinctrl-%d properties. Of all the pinctrl-%d properties, 99.5%
> (9486) are made up of pinctrl-[0-2].
> 
> Trying to parse all pinctrl-* properties and checking for pinctrl-%d is
> unnecessarily complicated. So, just add support for pinctrl-[0-8] for
> now. In the unlikely event we ever exceed pinctrl-8, we can come back
> and improve this.

If you were to implement the more general pinctrl-* case, roughly what would
it look like (pseudo-code or english description is fine).

-Frank

> 
> Signed-off-by: Saravana Kannan <saravanak@google.com>
> ---
>  drivers/of/property.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/drivers/of/property.c b/drivers/of/property.c
> index b06edeb1f88b..d40d923ffeaf 100644
> --- a/drivers/of/property.c
> +++ b/drivers/of/property.c
> @@ -1274,6 +1274,15 @@ DEFINE_SIMPLE_PROP(interrupts_extended, "interrupts-extended",
>  DEFINE_SIMPLE_PROP(nvmem_cells, "nvmem-cells", NULL)
>  DEFINE_SIMPLE_PROP(phys, "phys", "#phy-cells")
>  DEFINE_SIMPLE_PROP(wakeup_parent, "wakeup-parent", NULL)
> +DEFINE_SIMPLE_PROP(pinctrl0, "pinctrl-0", NULL)
> +DEFINE_SIMPLE_PROP(pinctrl1, "pinctrl-1", NULL)
> +DEFINE_SIMPLE_PROP(pinctrl2, "pinctrl-2", NULL)
> +DEFINE_SIMPLE_PROP(pinctrl3, "pinctrl-3", NULL)
> +DEFINE_SIMPLE_PROP(pinctrl4, "pinctrl-4", NULL)
> +DEFINE_SIMPLE_PROP(pinctrl5, "pinctrl-5", NULL)
> +DEFINE_SIMPLE_PROP(pinctrl6, "pinctrl-6", NULL)
> +DEFINE_SIMPLE_PROP(pinctrl7, "pinctrl-7", NULL)
> +DEFINE_SIMPLE_PROP(pinctrl8, "pinctrl-8", NULL)
>  DEFINE_SUFFIX_PROP(regulators, "-supply", NULL)
>  DEFINE_SUFFIX_PROP(gpio, "-gpio", "#gpio-cells")
>  DEFINE_SUFFIX_PROP(gpios, "-gpios", "#gpio-cells")
> @@ -1303,6 +1312,15 @@ static const struct supplier_bindings of_supplier_bindings[] = {
>  	{ .parse_prop = parse_nvmem_cells, },
>  	{ .parse_prop = parse_phys, },
>  	{ .parse_prop = parse_wakeup_parent, },
> +	{ .parse_prop = parse_pinctrl0, },
> +	{ .parse_prop = parse_pinctrl1, },
> +	{ .parse_prop = parse_pinctrl2, },
> +	{ .parse_prop = parse_pinctrl3, },
> +	{ .parse_prop = parse_pinctrl4, },
> +	{ .parse_prop = parse_pinctrl5, },
> +	{ .parse_prop = parse_pinctrl6, },
> +	{ .parse_prop = parse_pinctrl7, },
> +	{ .parse_prop = parse_pinctrl8, },
>  	{ .parse_prop = parse_regulators, },
>  	{ .parse_prop = parse_gpio, },
>  	{ .parse_prop = parse_gpios, },
> 

Re: [PATCH v1 2/2] of: property: Add device link support for pinctrl-0 through pinctrl-8

[Saravana Kannan]

On Wed, Jul 22, 2020 at 1:56 PM Frank Rowand <frowand.list@gmail.com> wrote:
>
> On 2020-07-22 15:13, Saravana Kannan wrote:
> > Add support for pinctrl-0 through pinctrl-8 explicitly instead of trying
> > to add support for pinctrl-%d properties.
> >
> > Of all the pinctrl-* properties in dts files (20322), only 47% (9531)
> > are pinctrl-%d properties. Of all the pinctrl-%d properties, 99.5%
> > (9486) are made up of pinctrl-[0-2].
> >
> > Trying to parse all pinctrl-* properties and checking for pinctrl-%d is
> > unnecessarily complicated. So, just add support for pinctrl-[0-8] for
> > now. In the unlikely event we ever exceed pinctrl-8, we can come back
> > and improve this.
>
> If you were to implement the more general pinctrl-* case, roughly what would
> it look like (pseudo-code or english description is fine).

So when I say "unnecessarily complicated", it's in terms of
readability. I can't use these macros -- which are succinct 1 line
entries that are super easy to understand.

Pseudo code:
parse_pinctrl(np, prop_name, index)
{
    if (doens't start with "pinctrl-")
        return NULL;
    ret = kstrtouint(propname + strlen("pinctrl"), 10, &val);

    check that it's not something line "pinctrl-2nd-val" that'll still
set val to 2.

    parse phandle with args and return phandle node.
}

All this when effectively 99.5% of the DT just use pinctrl-0,
pinctrl-1 and pinctrl-2. There are a few that use pinctrl-3. And
literally 6 DT files in the entire kernel source tree use pinctrl-4 or
greater.

And for those 6 files, pinctrl-[0-8] really point to the same pinctrl
node. So even if I didn't parse pinctrl-[4-8], all the device
dependencies would be tracked properly.

-Saravana

Re: [PATCH v1 2/2] of: property: Add device link support for pinctrl-0 through pinctrl-8

[Rob Herring]

On Wed, Jul 22, 2020 at 2:13 PM Saravana Kannan <saravanak@google.com> wrote:
>
> Add support for pinctrl-0 through pinctrl-8 explicitly instead of trying
> to add support for pinctrl-%d properties.
>
> Of all the pinctrl-* properties in dts files (20322), only 47% (9531)
> are pinctrl-%d properties. Of all the pinctrl-%d properties, 99.5%
> (9486) are made up of pinctrl-[0-2].
>
> Trying to parse all pinctrl-* properties and checking for pinctrl-%d is
> unnecessarily complicated. So, just add support for pinctrl-[0-8] for
> now. In the unlikely event we ever exceed pinctrl-8, we can come back
> and improve this.

It wasn't immediately clear from this that pinctrl-8 is the current
max you found vs. a should be enough for a while.

Pinctrl is also a bit special in that we have 100s of child nodes and
only 1 to a few actual dependencies (the pinctrl node). I assume in
the end here, it's just the pin controller node that's the dependency
rather than creating lot's of dependencies?

Rob

Re: [PATCH v1 2/2] of: property: Add device link support for pinctrl-0 through pinctrl-8

[Saravana Kannan]

On Wed, Jul 22, 2020 at 2:09 PM Rob Herring <robh+dt@kernel.org> wrote:
>
> On Wed, Jul 22, 2020 at 2:13 PM Saravana Kannan <saravanak@google.com> wrote:
> >
> > Add support for pinctrl-0 through pinctrl-8 explicitly instead of trying
> > to add support for pinctrl-%d properties.
> >
> > Of all the pinctrl-* properties in dts files (20322), only 47% (9531)
> > are pinctrl-%d properties. Of all the pinctrl-%d properties, 99.5%
> > (9486) are made up of pinctrl-[0-2].
> >
> > Trying to parse all pinctrl-* properties and checking for pinctrl-%d is
> > unnecessarily complicated. So, just add support for pinctrl-[0-8] for
> > now. In the unlikely event we ever exceed pinctrl-8, we can come back
> > and improve this.
>
> It wasn't immediately clear from this that pinctrl-8 is the current
> max you found vs. a should be enough for a while.

Hmmm... I tried. Looks like I failed. Open to copy-pasting any commit
text that you think will make it clearer.

> Pinctrl is also a bit special in that we have 100s of child nodes and
> only 1 to a few actual dependencies (the pinctrl node). I assume in
> the end here, it's just the pin controller node that's the dependency
> rather than creating lot's of dependencies?

Correct. In the end, it just links to the one (or few) pin controller
devices. Is there a requirement that all pinctrl-N properties point to
the child state nodes of the same pin-controller node? Or can
pinctrl-0 point to one and pinctrl-1 point to another pin controller
node? If the former, all I'd need to do is parse pinctrl-0.

-Saravana

Re: [PATCH v1 2/2] of: property: Add device link support for pinctrl-0 through pinctrl-8

[Rob Herring]

On Wed, Jul 22, 2020 at 7:08 PM Saravana Kannan <saravanak@google.com> wrote:
>
> On Wed, Jul 22, 2020 at 2:09 PM Rob Herring <robh+dt@kernel.org> wrote:
> >
> > On Wed, Jul 22, 2020 at 2:13 PM Saravana Kannan <saravanak@google.com> wrote:
> > >
> > > Add support for pinctrl-0 through pinctrl-8 explicitly instead of trying
> > > to add support for pinctrl-%d properties.
> > >
> > > Of all the pinctrl-* properties in dts files (20322), only 47% (9531)
> > > are pinctrl-%d properties. Of all the pinctrl-%d properties, 99.5%
> > > (9486) are made up of pinctrl-[0-2].
> > >
> > > Trying to parse all pinctrl-* properties and checking for pinctrl-%d is
> > > unnecessarily complicated. So, just add support for pinctrl-[0-8] for
> > > now. In the unlikely event we ever exceed pinctrl-8, we can come back
> > > and improve this.
> >
> > It wasn't immediately clear from this that pinctrl-8 is the current
> > max you found vs. a should be enough for a while.
>
> Hmmm... I tried. Looks like I failed. Open to copy-pasting any commit
> text that you think will make it clearer.

Append to the 2nd paragraph: 'pinctrl-8' is the current maximum found
in dts files.

> > Pinctrl is also a bit special in that we have 100s of child nodes and
> > only 1 to a few actual dependencies (the pinctrl node). I assume in
> > the end here, it's just the pin controller node that's the dependency
> > rather than creating lot's of dependencies?
>
> Correct. In the end, it just links to the one (or few) pin controller
> devices. Is there a requirement that all pinctrl-N properties point to
> the child state nodes of the same pin-controller node? Or can
> pinctrl-0 point to one and pinctrl-1 point to another pin controller
> node? If the former, all I'd need to do is parse pinctrl-0.

My initial thought was I'd expect the dependencies to be uniform
across pinctrl-%d properties as each one is supposed to be a different
mode of the same set of pins. However, the dra7 pathologic cases don't
follow that exactly with the higher speed MMC modes having an
additional i/o delay controller setting.

Rob