2021-10-12 12:28:01

by Horatiu Vultur

Subject: [PATCH] pinctrl: microchip sgpio: use reset driver

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 <[email protected]>
---
drivers/pinctrl/pinctrl-microchip-sgpio.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/pinctrl/pinctrl-microchip-sgpio.c b/drivers/pinctrl/pinctrl-microchip-sgpio.c
index 072bccdea2a5..e8a91d0824cb 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 +815,10 @@ static int microchip_sgpio_probe(struct platform_device *pdev)

priv->dev = dev;

+ reset = devm_reset_control_get_shared(&pdev->dev, "switch");
+ if (!IS_ERR(reset))
+ 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

2021-10-12 13:43:07

by Philipp Zabel

Subject: Re: [PATCH] pinctrl: microchip sgpio: use reset driver

On Tue, 2021-10-12 at 14:24 +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 <[email protected]>
> ---
> drivers/pinctrl/pinctrl-microchip-sgpio.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/drivers/pinctrl/pinctrl-microchip-sgpio.c b/drivers/pinctrl/pinctrl-microchip-sgpio.c
> index 072bccdea2a5..e8a91d0824cb 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 +815,10 @@ static int microchip_sgpio_probe(struct platform_device *pdev)
>
> priv->dev = dev;
>
> + reset = devm_reset_control_get_shared(&pdev->dev, "switch");

This seems to be missing an update to the devicetree binding.

Just to make sure we aren't introducing a circular dependency here, are
the PHY reset GPIOs that are toggled by the "switch" reset controller in
[1] provided by one of the sgpio controllers?

[1] https://lore.kernel.org/all/[email protected]/

regards
Philipp

2021-10-12 14:44:09

by Horatiu Vultur

Subject: Re: [PATCH] pinctrl: microchip sgpio: use reset driver

Hi Philipp,

The 10/12/2021 15:40, Philipp Zabel wrote:
>
> On Tue, 2021-10-12 at 14:24 +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 <[email protected]>
> > ---
> > drivers/pinctrl/pinctrl-microchip-sgpio.c | 6 ++++++
> > 1 file changed, 6 insertions(+)
> >
> > diff --git a/drivers/pinctrl/pinctrl-microchip-sgpio.c b/drivers/pinctrl/pinctrl-microchip-sgpio.c
> > index 072bccdea2a5..e8a91d0824cb 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 +815,10 @@ static int microchip_sgpio_probe(struct platform_device *pdev)
> >
> > priv->dev = dev;
> >
> > + reset = devm_reset_control_get_shared(&pdev->dev, "switch");
>
> This seems to be missing an update to the devicetree binding.

Yes, I will fix this in the next version.

>
> Just to make sure we aren't introducing a circular dependency here, are
> the PHY reset GPIOs that are toggled by the "switch" reset controller in
> [1] provided by one of the sgpio controllers?
>
> [1] https://lore.kernel.org/all/[email protected]/

Nope, the GPIOs are provided by a differnet gpio controller.

>
> regards
> Philipp

--
/Horatiu