[PATCH v6 0/2] pinctrl: pinctrl-microchip-sgpio: Extend to call reset driver

[PATCH v6 0/2] pinctrl: pinctrl-microchip-sgpio: Extend to call reset driver

[Horatiu Vultur]

This allows the driver to call an optional reset driver.

v5->v6:
 - fix warnings reported by 'make dtbs_check'
 - add back the name of the reset line

v4->v5:
 - check the return value of devm_reset_control_get_optional_shared

v3->v4:
 - use devm_reset_control_get_optional_shared
 - remove the expected name of the reset line

v2->v3:
 - fix warnings reported by 'make dtbs_check'

v1->v2:
 - add dt-bindings changes

Horatiu Vultur (2):
  dt-bindings: pinctrl: pinctrl-microchip-sgpio: Add reset binding
  pinctrl: microchip sgpio: use reset driver

 .../bindings/pinctrl/microchip,sparx5-sgpio.yaml           | 7 +++++++
 drivers/pinctrl/pinctrl-microchip-sgpio.c                  | 7 +++++++
 2 files changed, 14 insertions(+)

-- 
2.33.0

[PATCH v6 1/2] dt-bindings: pinctrl: pinctrl-microchip-sgpio: Add reset binding

[Horatiu Vultur]

This describes the new binding which allows to call a reset driver from
the pinctrl-microchip-sgpio driver.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
---
 .../bindings/pinctrl/microchip,sparx5-sgpio.yaml           | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Documentation/devicetree/bindings/pinctrl/microchip,sparx5-sgpio.yaml b/Documentation/devicetree/bindings/pinctrl/microchip,sparx5-sgpio.yaml
index 4fe35e650909..cb554084bdf1 100644
--- a/Documentation/devicetree/bindings/pinctrl/microchip,sparx5-sgpio.yaml
+++ b/Documentation/devicetree/bindings/pinctrl/microchip,sparx5-sgpio.yaml
@@ -68,6 +68,13 @@ properties:
       clock, and larger than zero.
     default: 12500000
 
+  resets:
+    maxItems: 1
+
+  reset-names:
+    items:
+      - const: switch
+
 patternProperties:
   "^gpio@[0-1]$":
     type: object
-- 
2.33.0

[PATCH v6 2/2] pinctrl: microchip sgpio: use reset driver

[Horatiu Vultur]

On lan966x platform when the switch gets reseted then also the sgpio
gets reseted. The fix for this is to extend also the sgpio driver to
call the reset driver which will be reseted only once by the first
driver that is probed.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
---
 drivers/pinctrl/pinctrl-microchip-sgpio.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/pinctrl/pinctrl-microchip-sgpio.c b/drivers/pinctrl/pinctrl-microchip-sgpio.c
index 072bccdea2a5..78765faa245a 100644
--- a/drivers/pinctrl/pinctrl-microchip-sgpio.c
+++ b/drivers/pinctrl/pinctrl-microchip-sgpio.c
@@ -17,6 +17,7 @@
 #include <linux/pinctrl/pinmux.h>
 #include <linux/platform_device.h>
 #include <linux/property.h>
+#include <linux/reset.h>
 
 #include "core.h"
 #include "pinconf.h"
@@ -803,6 +804,7 @@ static int microchip_sgpio_probe(struct platform_device *pdev)
 	int div_clock = 0, ret, port, i, nbanks;
 	struct device *dev = &pdev->dev;
 	struct fwnode_handle *fwnode;
+	struct reset_control *reset;
 	struct sgpio_priv *priv;
 	struct clk *clk;
 	u32 val;
@@ -813,6 +815,11 @@ static int microchip_sgpio_probe(struct platform_device *pdev)
 
 	priv->dev = dev;
 
+	reset = devm_reset_control_get_optional_shared(&pdev->dev, "switch");
+	if (IS_ERR(reset))
+		return dev_err_probe(dev, PTR_ERR(reset), "Failed to get reset\n");
+	reset_control_reset(reset);
+
 	clk = devm_clk_get(dev, NULL);
 	if (IS_ERR(clk))
 		return dev_err_probe(dev, PTR_ERR(clk), "Failed to get clock\n");
-- 
2.33.0

Re: [PATCH v6 2/2] pinctrl: microchip sgpio: use reset driver

[Philipp Zabel]

Hi Horatiu,

On Mon, 2021-10-18 at 10:57 +0200, Horatiu Vultur wrote:
> On lan966x platform when the switch gets reseted then also the sgpio
> gets reseted. The fix for this is to extend also the sgpio driver to
> call the reset driver which will be reseted only once by the first
> driver that is probed.
> 
> Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
> ---
>  drivers/pinctrl/pinctrl-microchip-sgpio.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/pinctrl/pinctrl-microchip-sgpio.c b/drivers/pinctrl/pinctrl-microchip-sgpio.c
> index 072bccdea2a5..78765faa245a 100644
> --- a/drivers/pinctrl/pinctrl-microchip-sgpio.c
> +++ b/drivers/pinctrl/pinctrl-microchip-sgpio.c
> @@ -17,6 +17,7 @@
>  #include <linux/pinctrl/pinmux.h>
>  #include <linux/platform_device.h>
>  #include <linux/property.h>
> +#include <linux/reset.h>
>  
>  #include "core.h"
>  #include "pinconf.h"
> @@ -803,6 +804,7 @@ static int microchip_sgpio_probe(struct platform_device *pdev)
>  	int div_clock = 0, ret, port, i, nbanks;
>  	struct device *dev = &pdev->dev;
>  	struct fwnode_handle *fwnode;
> +	struct reset_control *reset;
>  	struct sgpio_priv *priv;
>  	struct clk *clk;
>  	u32 val;
> @@ -813,6 +815,11 @@ static int microchip_sgpio_probe(struct platform_device *pdev)
>  
>  	priv->dev = dev;
>  
> +	reset = devm_reset_control_get_optional_shared(&pdev->dev, "switch");

This is the first GPIO driver that I am aware of that requests a named
reset control, so I'm still not sure if this should be called "switch"
instead of "gpio" or just "reset", just in case there is a future model
where the GPIO controller reset is not shared with the switch reset.

> +	if (IS_ERR(reset))
> +		return dev_err_probe(dev, PTR_ERR(reset), "Failed to get reset\n");
> +	reset_control_reset(reset);
> +
>  	clk = devm_clk_get(dev, NULL);
>  	if (IS_ERR(clk))
>  		return dev_err_probe(dev, PTR_ERR(clk), "Failed to get clock\n");

But whichever name you choose, the code is

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>

regards
Philipp

Re: [PATCH v6 2/2] pinctrl: microchip sgpio: use reset driver

[Horatiu Vultur]

The 10/18/2021 12:37, Philipp Zabel wrote:

Hi Philipp,
> 
> Hi Horatiu,
> 
> On Mon, 2021-10-18 at 10:57 +0200, Horatiu Vultur wrote:
> > On lan966x platform when the switch gets reseted then also the sgpio
> > gets reseted. The fix for this is to extend also the sgpio driver to
> > call the reset driver which will be reseted only once by the first
> > driver that is probed.
> >
> > Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
> > ---
> >  drivers/pinctrl/pinctrl-microchip-sgpio.c | 7 +++++++
> >  1 file changed, 7 insertions(+)
> >
> > diff --git a/drivers/pinctrl/pinctrl-microchip-sgpio.c b/drivers/pinctrl/pinctrl-microchip-sgpio.c
> > index 072bccdea2a5..78765faa245a 100644
> > --- a/drivers/pinctrl/pinctrl-microchip-sgpio.c
> > +++ b/drivers/pinctrl/pinctrl-microchip-sgpio.c
> > @@ -17,6 +17,7 @@
> >  #include <linux/pinctrl/pinmux.h>
> >  #include <linux/platform_device.h>
> >  #include <linux/property.h>
> > +#include <linux/reset.h>
> >
> >  #include "core.h"
> >  #include "pinconf.h"
> > @@ -803,6 +804,7 @@ static int microchip_sgpio_probe(struct platform_device *pdev)
> >       int div_clock = 0, ret, port, i, nbanks;
> >       struct device *dev = &pdev->dev;
> >       struct fwnode_handle *fwnode;
> > +     struct reset_control *reset;
> >       struct sgpio_priv *priv;
> >       struct clk *clk;
> >       u32 val;
> > @@ -813,6 +815,11 @@ static int microchip_sgpio_probe(struct platform_device *pdev)
> >
> >       priv->dev = dev;
> >
> > +     reset = devm_reset_control_get_optional_shared(&pdev->dev, "switch");
> 
> This is the first GPIO driver that I am aware of that requests a named
> reset control, so I'm still not sure if this should be called "switch"
> instead of "gpio" or just "reset", just in case there is a future model
> where the GPIO controller reset is not shared with the switch reset.

I agree, it is not the best name. But the name "switch" was already used
in DT by sparx5[1], so I just went with this name.

> 
> > +     if (IS_ERR(reset))
> > +             return dev_err_probe(dev, PTR_ERR(reset), "Failed to get reset\n");
> > +     reset_control_reset(reset);
> > +
> >       clk = devm_clk_get(dev, NULL);
> >       if (IS_ERR(clk))
> >               return dev_err_probe(dev, PTR_ERR(clk), "Failed to get clock\n");
> 
> But whichever name you choose, the code is
> 
> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
> 
> regards
> Philipp

[1] https://elixir.bootlin.com/linux/v5.15-rc5/source/arch/arm64/boot/dts/microchip/sparx5.dtsi#L307

-- 
/Horatiu

Re: [PATCH v6 2/2] pinctrl: microchip sgpio: use reset driver

[Philipp Zabel]

On Mon, 2021-10-18 at 13:12 +0200, Horatiu Vultur wrote:
> The 10/18/2021 12:37, Philipp Zabel wrote:
> 
> Hi Philipp,
> > Hi Horatiu,
> > 
> > On Mon, 2021-10-18 at 10:57 +0200, Horatiu Vultur wrote:
> > > On lan966x platform when the switch gets reseted then also the sgpio
> > > gets reseted. The fix for this is to extend also the sgpio driver to
> > > call the reset driver which will be reseted only once by the first
> > > driver that is probed.
> > > 
> > > Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
> > > ---
> > >  drivers/pinctrl/pinctrl-microchip-sgpio.c | 7 +++++++
> > >  1 file changed, 7 insertions(+)
> > > 
> > > diff --git a/drivers/pinctrl/pinctrl-microchip-sgpio.c b/drivers/pinctrl/pinctrl-microchip-sgpio.c
> > > index 072bccdea2a5..78765faa245a 100644
> > > --- a/drivers/pinctrl/pinctrl-microchip-sgpio.c
> > > +++ b/drivers/pinctrl/pinctrl-microchip-sgpio.c
> > > @@ -17,6 +17,7 @@
> > >  #include <linux/pinctrl/pinmux.h>
> > >  #include <linux/platform_device.h>
> > >  #include <linux/property.h>
> > > +#include <linux/reset.h>
> > > 
> > >  #include "core.h"
> > >  #include "pinconf.h"
> > > @@ -803,6 +804,7 @@ static int microchip_sgpio_probe(struct platform_device *pdev)
> > >       int div_clock = 0, ret, port, i, nbanks;
> > >       struct device *dev = &pdev->dev;
> > >       struct fwnode_handle *fwnode;
> > > +     struct reset_control *reset;
> > >       struct sgpio_priv *priv;
> > >       struct clk *clk;
> > >       u32 val;
> > > @@ -813,6 +815,11 @@ static int microchip_sgpio_probe(struct platform_device *pdev)
> > > 
> > >       priv->dev = dev;
> > > 
> > > +     reset = devm_reset_control_get_optional_shared(&pdev->dev, "switch");
> > 
> > This is the first GPIO driver that I am aware of that requests a named
> > reset control, so I'm still not sure if this should be called "switch"
> > instead of "gpio" or just "reset", just in case there is a future model
> > where the GPIO controller reset is not shared with the switch reset.
> 
> I agree, it is not the best name. But the name "switch" was already used
> in DT by sparx5[1], so I just went with this name.

Oh, ok, in that case the decision already has been made.

regards
Philipp

Re: [PATCH v6 1/2] dt-bindings: pinctrl: pinctrl-microchip-sgpio: Add reset binding

[Rob Herring]

On Mon, 18 Oct 2021 10:57:53 +0200, Horatiu Vultur wrote:
> This describes the new binding which allows to call a reset driver from
> the pinctrl-microchip-sgpio driver.
> 
> Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
> ---
>  .../bindings/pinctrl/microchip,sparx5-sgpio.yaml           | 7 +++++++
>  1 file changed, 7 insertions(+)
> 

Reviewed-by: Rob Herring <robh@kernel.org>

Re: [PATCH v6 2/2] pinctrl: microchip sgpio: use reset driver

[Steen Hegelund]

On Mon, 2021-10-18 at 10:57 +0200, Horatiu Vultur wrote:
> On lan966x platform when the switch gets reseted then also the sgpio
> gets reseted. The fix for this is to extend also the sgpio driver to
> call the reset driver which will be reseted only once by the first
> driver that is probed.
> 
> Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>

Reviewed-by: Steen Hegelund <steen.hegelund@microchip.com> 

-- 
BR
Steen

-=-=-=-=-=-=-=-=-=-=-=-=-=-=
steen.hegelund@microchip.com

Re: [PATCH v6 0/2] pinctrl: pinctrl-microchip-sgpio: Extend to call reset driver

[Linus Walleij]

On Mon, Oct 18, 2021 at 10:56 AM Horatiu Vultur
<horatiu.vultur@microchip.com> wrote:

> v5->v6:
>  - fix warnings reported by 'make dtbs_check'
>  - add back the name of the reset line

Patch set v6 applied, thanks for working this out!

Yours,
Linus Walleij