Re: [PATCH 5/7] usb: gadget: udc: add Renesas RZ/N1 USBF controller support

Herve Codina
2022-11-07T15:23:35Z

Hi Geert,

On Mon, 7 Nov 2022 15:37:40 +0100
Geert Uytterhoeven <geert@linux-m68k.org> wrote:

> Hi Hervé,
>
> On Mon, Nov 7, 2022 at 3:00 PM Herve Codina <herve.codina@bootlin.com> wrote:
> > Add support for the Renesas USBF controller.
> > This controller is an USB2.0 UDC controller available in the
> > Renesas r9a06g032 SoC (RZ/N1 family).
> >
> > Signed-off-by: Herve Codina <herve.codina@bootlin.com>
>
> > --- /dev/null
> > +++ b/drivers/usb/gadget/udc/renesas_usbf.c
>
> > +struct usbf_udc {
> > + struct usb_gadget gadget;
> > + struct usb_gadget_driver *driver;
> > + struct device *dev;
> > + struct clk_bulk_data *clocks;
> > + int nclocks;
> > + void __iomem *regs;
> > + spinlock_t lock;
> > + bool is_remote_wakeup;
> > + bool is_usb_suspended;
> > + struct usbf_ep ep[USBF_NUM_ENDPOINTS];
> > + /* for EP0 control messages */
> > + enum usbf_ep0state ep0state;
> > + struct usbf_req setup_reply;
> > + u8 ep0_buf[USBF_EP0_MAX_PCKT_SIZE];
> > +};
>
> > +static int usbf_probe(struct platform_device *pdev)
> > +{
> > + struct device *dev = &pdev->dev;
> > + struct usbf_udc *udc;
> > + struct usbf_ep *ep;
> > + bool h2mode;
> > + int irq;
> > + int ret;
> > + int i;
> > +
> > + ret = r9a06g032_sysctrl_get_usb_h2mode(&h2mode);
> > + if (ret)
> > + return ret;
> > + if (h2mode) {
> > + dev_warn(dev, "Disabled in H2 (host) mode\n");
> > + return -ENODEV;
> > + }
> > +
> > + udc = devm_kzalloc(dev, sizeof(*udc), GFP_KERNEL);
> > + if (!udc)
> > + return -ENOMEM;
> > + platform_set_drvdata(pdev, udc);
> > +
> > + udc->dev = dev;
> > + spin_lock_init(&udc->lock);
> > +
> > + udc->regs = devm_platform_ioremap_resource(pdev, 0);
> > + if (IS_ERR(udc->regs))
> > + return PTR_ERR(udc->regs);
> > +
> > + devm_pm_runtime_enable(&pdev->dev);
> > + ret = pm_runtime_resume_and_get(&pdev->dev);
> > + if (ret < 0)
> > + return ret;
> > +
> > + ret = devm_clk_bulk_get_all(dev, &udc->clocks);
> > + if (ret < 1) {
> > + dev_err(dev, "failed to get clocks %d\n", ret);
> > + return ret;
> > + }
> > + udc->nclocks = ret;
> > +
> > + ret = clk_bulk_prepare_enable(udc->nclocks, udc->clocks);
> > + if (ret) {
> > + dev_err(dev, "can not enable the clock\n");
> > + return ret;
> > + }
>
> As this driver only enables/disables the clocks, perhaps you could
> just delegate this to Runtime PM (through the clock domain pointed
> by the power-domains property in DT), and drop the .clocks and
> .nclocks fields?

Yes, indeed.
I tested it and it works.
I will remove the the clocks handling from this driver in v2 series.

>
> > +clk_disable:
> > + clk_bulk_disable_unprepare(udc->nclocks, udc->clocks);
> > + return ret;
> > +}
> > +
> > +static int usbf_remove(struct platform_device *pdev)
> > +{
> > + struct usbf_udc *udc = platform_get_drvdata(pdev);
> > +
> > + usb_del_gadget_udc(&udc->gadget);
> > +
> > + clk_bulk_disable_unprepare(udc->nclocks, udc->clocks);
> > +
> > + pm_runtime_put(&pdev->dev);
> > +
> > + return 0;
> > +}
>
> > +MODULE_AUTHOR("Herve Codina <herve.codina@bootlin.com>");
>
> Hervé? ;-)

Just to be consistent with other places where my email appears,
I keep "Herve" :)

>
> > +MODULE_DESCRIPTION("Renesas R-Car Gen3 & RZ/N1 USB Function driver");
> > +MODULE_LICENSE("GPL");
>
> > --
> > 2.37.3
> >
>
>
> --
> 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 for this review,
Hervé

--
Hervé Codina, Bootlin
Embedded Linux and Kernel engineering