diff mbox series

[3/7] soc: renesas: r9a06g032-sysctrl: Handle h2mode device-tree property

Message ID 20221107135825.583877-4-herve.codina@bootlin.com
State New
Headers
Series Add the Renesas USBF controller support |

Commit Message

Herve Codina Nov. 7, 2022, 1:58 p.m. UTC 
  Handle the h2mode property and forces the CFG_USB[H2MODE] bit
accordingly.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
---
 drivers/clk/renesas/r9a06g032-clocks.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

Comments

Geert Uytterhoeven Nov. 7, 2022, 3:18 p.m. UTC | #1 
Hi Hervé,

On Mon, Nov 7, 2022 at 2:59 PM Herve Codina <herve.codina@bootlin.com> wrote:
> Handle the h2mode property and forces the CFG_USB[H2MODE] bit
> accordingly.
>
> Signed-off-by: Herve Codina <herve.codina@bootlin.com>

Thanks for your patch!

> --- a/drivers/clk/renesas/r9a06g032-clocks.c
> +++ b/drivers/clk/renesas/r9a06g032-clocks.c
> @@ -946,6 +946,7 @@ static int __init r9a06g032_clocks_probe(struct platform_device *pdev)
>         struct clk *mclk;
>         unsigned int i;
>         u16 uart_group_sel[2];
> +       u32 usb, h2mode;
>         int error;
>
>         clocks = devm_kzalloc(dev, sizeof(*clocks), GFP_KERNEL);
> @@ -966,6 +967,26 @@ static int __init r9a06g032_clocks_probe(struct platform_device *pdev)
>         clocks->reg = of_iomap(np, 0);
>         if (WARN_ON(!clocks->reg))
>                 return -ENOMEM;
> +
> +       error = of_property_read_u32(np, "renesas,h2mode", &h2mode);
> +       if (!error) {
> +               usb = readl(clocks->reg + R9A06G032_SYSCTRL_USB);
> +               switch (h2mode) {
> +               case 0:
> +                       /* 1 host, 1 device */
> +                       usb &= ~R9A06G032_SYSCTRL_USB_H2MODE;
> +                       break;
> +               case 1:
> +                       /* 2 hosts */
> +                       usb |= R9A06G032_SYSCTRL_USB_H2MODE;
> +                       break;
> +               default:
> +                       dev_err(dev, "invalid h2mode %d\n", h2mode);
> +                       return -EINVAL;
> +               }
> +               writel(usb, clocks->reg + R9A06G032_SYSCTRL_USB);

Reading the big fat warnings in the documentation about changing
this at runtime (disconnect nodes, reset clocks, ...), I'm wondering if
the above is sufficient?

> +       }
> +
>         for (i = 0; i < ARRAY_SIZE(r9a06g032_clocks); ++i) {
>                 const struct r9a06g032_clkdesc *d = &r9a06g032_clocks[i];
>                 const char *parent_name = d->source ?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
Herve Codina Nov. 7, 2022, 4:36 p.m. UTC | #2 
Hi Geert,

On Mon, 7 Nov 2022 16:18:06 +0100
Geert Uytterhoeven <geert@linux-m68k.org> wrote:

> Hi Hervé,
> 
> On Mon, Nov 7, 2022 at 2:59 PM Herve Codina <herve.codina@bootlin.com> wrote:
> > Handle the h2mode property and forces the CFG_USB[H2MODE] bit
> > accordingly.
> >
> > Signed-off-by: Herve Codina <herve.codina@bootlin.com>  
> 
> Thanks for your patch!
> 
> > --- a/drivers/clk/renesas/r9a06g032-clocks.c
> > +++ b/drivers/clk/renesas/r9a06g032-clocks.c
> > @@ -946,6 +946,7 @@ static int __init r9a06g032_clocks_probe(struct platform_device *pdev)
> >         struct clk *mclk;
> >         unsigned int i;
> >         u16 uart_group_sel[2];
> > +       u32 usb, h2mode;
> >         int error;
> >
> >         clocks = devm_kzalloc(dev, sizeof(*clocks), GFP_KERNEL);
> > @@ -966,6 +967,26 @@ static int __init r9a06g032_clocks_probe(struct platform_device *pdev)
> >         clocks->reg = of_iomap(np, 0);
> >         if (WARN_ON(!clocks->reg))
> >                 return -ENOMEM;
> > +
> > +       error = of_property_read_u32(np, "renesas,h2mode", &h2mode);
> > +       if (!error) {
> > +               usb = readl(clocks->reg + R9A06G032_SYSCTRL_USB);
> > +               switch (h2mode) {
> > +               case 0:
> > +                       /* 1 host, 1 device */
> > +                       usb &= ~R9A06G032_SYSCTRL_USB_H2MODE;
> > +                       break;
> > +               case 1:
> > +                       /* 2 hosts */
> > +                       usb |= R9A06G032_SYSCTRL_USB_H2MODE;
> > +                       break;
> > +               default:
> > +                       dev_err(dev, "invalid h2mode %d\n", h2mode);
> > +                       return -EINVAL;
> > +               }
> > +               writel(usb, clocks->reg + R9A06G032_SYSCTRL_USB);  
> 
> Reading the big fat warnings in the documentation about changing
> this at runtime (disconnect nodes, reset clocks, ...), I'm wondering if
> the above is sufficient?

Well, indeed we should "disconnect all module operated by USBPLL clock 
from the NoC interconnect".

I am a bit lost in the sysctrl driver and the clock/reset stuffs.
In fact, I don't really know how to do that.

I thought that setting the H2MODE value at the clock probe function would
be sufficient, expecting that the connections would not be already done
and I didn't see any issues on my system.

Maybe I missed the bootloader that could have already done some connections.

Can someone help ?

> 
> > +       }
> > +
> >         for (i = 0; i < ARRAY_SIZE(r9a06g032_clocks); ++i) {
> >                 const struct r9a06g032_clkdesc *d = &r9a06g032_clocks[i];
> >                 const char *parent_name = d->source ?  
> 
> Gr{oetje,eeting}s,
> 
>                         Geert
> 
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
> 
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds

Thanks,
Hervé
diff mbox series

Patch

diff --git a/drivers/clk/renesas/r9a06g032-clocks.c b/drivers/clk/renesas/r9a06g032-clocks.c
index c07131c47a9f..562c2aba910b 100644
--- a/drivers/clk/renesas/r9a06g032-clocks.c
+++ b/drivers/clk/renesas/r9a06g032-clocks.c
@@ -946,6 +946,7 @@  static int __init r9a06g032_clocks_probe(struct platform_device *pdev)
 	struct clk *mclk;
 	unsigned int i;
 	u16 uart_group_sel[2];
+	u32 usb, h2mode;
 	int error;
 
 	clocks = devm_kzalloc(dev, sizeof(*clocks), GFP_KERNEL);
@@ -966,6 +967,26 @@  static int __init r9a06g032_clocks_probe(struct platform_device *pdev)
 	clocks->reg = of_iomap(np, 0);
 	if (WARN_ON(!clocks->reg))
 		return -ENOMEM;
+
+	error = of_property_read_u32(np, "renesas,h2mode", &h2mode);
+	if (!error) {
+		usb = readl(clocks->reg + R9A06G032_SYSCTRL_USB);
+		switch (h2mode) {
+		case 0:
+			/* 1 host, 1 device */
+			usb &= ~R9A06G032_SYSCTRL_USB_H2MODE;
+			break;
+		case 1:
+			/* 2 hosts */
+			usb |= R9A06G032_SYSCTRL_USB_H2MODE;
+			break;
+		default:
+			dev_err(dev, "invalid h2mode %d\n", h2mode);
+			return -EINVAL;
+		}
+		writel(usb, clocks->reg + R9A06G032_SYSCTRL_USB);
+	}
+
 	for (i = 0; i < ARRAY_SIZE(r9a06g032_clocks); ++i) {
 		const struct r9a06g032_clkdesc *d = &r9a06g032_clocks[i];
 		const char *parent_name = d->source ?