diff mbox series

pinctrl: microchip sgpio: use reset driver

Message ID 20211012122435.2081930-1-horatiu.vultur@microchip.com (mailing list archive)
State New, archived
Headers show
Series pinctrl: microchip sgpio: use reset driver | expand

Commit Message

Horatiu Vultur Oct. 12, 2021, 12:24 p.m. UTC
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 | 6 ++++++
 1 file changed, 6 insertions(+)

Comments

Philipp Zabel Oct. 12, 2021, 1:40 p.m. UTC | #1
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 <horatiu.vultur@microchip.com>
> ---
>  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/20211012114238.2060101-3-horatiu.vultur@microchip.com/

regards
Philipp
Horatiu Vultur Oct. 12, 2021, 2:43 p.m. UTC | #2
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 <horatiu.vultur@microchip.com>
> > ---
> >  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/20211012114238.2060101-3-horatiu.vultur@microchip.com/

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

> 
> regards
> Philipp
diff mbox series

Patch

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");