On Tue, Dec 10, 2013 at 2:55 AM, Vivek Gautam <gautam.vivek@xxxxxxxxxxx> wrote:
> The DWC3-exynos eXtensible host controller on Exynos5420 SoC
> is quirky in a way that the PHY needs to be tuned to get it
> working at SuperSpeed.
> By default this PHY works as High-speed phy and therefore
> detects even Super-speed devices as high-speed ones.
> So, the PHY needs to be tuned after controller has been reset.
>
> Adding a xHCI quirk for this purpose.
>
> Signed-off-by: Vivek Gautam <gautam.vivek@xxxxxxxxxxx>
> ---
> drivers/usb/host/xhci-plat.c | 19 +++++++++++++++++++
> drivers/usb/host/xhci.h | 1 +
> 2 files changed, 20 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
> index d9c169f..395c9e9 100644
> --- a/drivers/usb/host/xhci-plat.c
> +++ b/drivers/usb/host/xhci-plat.c
> @@ -21,6 +21,25 @@
>
> static void xhci_plat_quirks(struct device *dev, struct xhci_hcd *xhci)
> {
> + struct device *parent_dev;
> + struct device *vendor_parent_dev;
> +
> + parent_dev = dev->parent;
> + vendor_parent_dev = parent_dev->parent;
Is this guaranteed to exist for all current and future xhci-plat
controllers or should you maybe check one or both for NULL?
> +
> + /*
> + * The DWC3-exynos host controller on Exynos5420 SoC is quirky
> + * in a way that the PHY needs to be tuned to get it working
> + * at SuperSpeed. By default this PHY works as High-speed phy
> + * and so detects even Super-speed devices as high-speed ones.
> + * Therefor the PHY needs to be tuned after controller
> + * has been reset, since a controller reset actually forces the
> + * PHY to fall back to its default state wherein it works as
> + * High-Speed PHY only.
> + */
> + if (!strstr(dev_name(vendor_parent_dev), "exynos"))
> + xhci->quirks |= XHCI_DWC3_EXYNOS;
> +
> /*
> * As of now platform drivers don't provide MSI support so we ensure
> * here that the generic code does not try to make a pci_dev from our
> diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
> index 7807f62..f69af8c 100644
> --- a/drivers/usb/host/xhci.h
> +++ b/drivers/usb/host/xhci.h
> @@ -1560,6 +1560,7 @@ struct xhci_hcd {
> #define XHCI_PLAT (1 << 16)
> #define XHCI_SLOW_SUSPEND (1 << 17)
> #define XHCI_SPURIOUS_WAKEUP (1 << 18)
> +#define XHCI_DWC3_EXYNOS (1 << 19)
I think in general it's better to name quirks after what they do
rather than a specific device, that way you might be able to reuse
them. How about XHCI_TUNE_AFTER_RESET? (Or you could leave out the
quirk completely and just differentiate by whether the PHY implements
the tune() method or not.)
> unsigned int num_active_eps;
> unsigned int limit_active_eps;
> /* There are two roothubs to keep track of bus suspend info for */
> --
> 1.7.6.5
>
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
