Messages in this thread | | | Date | Wed, 29 Apr 2020 15:08:47 -0400 (EDT) | From | Alan Stern <> | Subject | Re: [PATCH v4 3/4] usb: ehci: Add new EHCI driver for Broadcom STB SoC's |
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On Wed, 29 Apr 2020, Al Cooper wrote:
> Add a new EHCI driver for Broadcom STB SoC's. A new EHCI driver > was created instead of adding support to the existing ehci platform > driver because of the code required to workaround bugs in the EHCI > controller. > > Signed-off-by: Al Cooper <alcooperx@gmail.com> > ---
...
> +static int __maybe_unused ehci_brcm_resume(struct device *dev) > +{ > + struct usb_hcd *hcd = dev_get_drvdata(dev); > + struct ehci_hcd *ehci = hcd_to_ehci(hcd); > + struct brcm_priv *priv = hcd_to_ehci_priv(hcd); > + int err; > + > + err = clk_prepare_enable(priv->clk); > + if (err) > + return err; > + /* > + * SWLINUX-1705: Avoid OUT packet underflows during high memory > + * bus usage > + * port_status[0x0f] = Broadcom-proprietary USB_EHCI_INSNREG00 > + * @ 0x90 > + */ > + ehci_writel(ehci, 0x00800040, &ehci->regs->port_status[0x10]); > + ehci_writel(ehci, 0x00000001, &ehci->regs->port_status[0x12]); > + > + ehci_resume(hcd, false); > + return 0; > +}
One extra thing that came to my attention recently... Like all other platform drivers, this has to set the runtime PM status of the controller at the end of a system resume. See
https://marc.info/?l=linux-usb&m=158773611612885&w=2
for an example.
Alan Stern
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