diff mbox

[v2,3/4] usb: host: xhci-plat: Caibrate PHY post host reset

Message ID 1404900096-1721-4-git-send-email-gautam.vivek@samsung.com (mailing list archive)
State New, archived
Headers show

Commit Message

Vivek Gautam July 9, 2014, 10:01 a.m. UTC
Some quirky PHYs may require to be calibrated post the host
controller initialization.
The USB 3.0 DRD PHY on Exynos5420/5800 systems, coming along with
Synopsys's DWC3 controller, is one such PHY which needs to be
calibrated post xhci's reset at initialization time and at
resume time, to get the controller work at SuperSpeed.

Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
---
 drivers/usb/host/xhci-plat.c |   39 +++++++++++++++++++++++++++++++++++++--
 1 file changed, 37 insertions(+), 2 deletions(-)

Comments

Julius Werner July 9, 2014, 5:58 p.m. UTC | #1
On Wed, Jul 9, 2014 at 3:01 AM, Vivek Gautam <gautam.vivek@samsung.com> wrote:
> Some quirky PHYs may require to be calibrated post the host
> controller initialization.
> The USB 3.0 DRD PHY on Exynos5420/5800 systems, coming along with
> Synopsys's DWC3 controller, is one such PHY which needs to be
> calibrated post xhci's reset at initialization time and at
> resume time, to get the controller work at SuperSpeed.
>
> Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
> ---
>  drivers/usb/host/xhci-plat.c |   39 +++++++++++++++++++++++++++++++++++++--
>  1 file changed, 37 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
> index e50bd7d..decf349 100644
> --- a/drivers/usb/host/xhci-plat.c
> +++ b/drivers/usb/host/xhci-plat.c
> @@ -35,7 +35,27 @@ static void xhci_plat_quirks(struct device *dev, struct xhci_hcd *xhci)
>  /* called during probe() after chip reset completes */
>  static int xhci_plat_setup(struct usb_hcd *hcd)
>  {
> -       return xhci_gen_setup(hcd, xhci_plat_quirks);
> +       struct device *parent;
> +       int ret;
> +
> +       ret = xhci_gen_setup(hcd, xhci_plat_quirks);
> +       if (ret) {
> +               dev_err(hcd->self.controller, "xhci setup failed\n");
> +               return ret;
> +       }
> +
> +       parent = hcd->self.controller->parent;
> +       if (of_device_is_compatible(parent->of_node, "synopsys,dwc3") ||
> +           of_device_is_compatible(parent->of_node, "snps,dwc3")) {
> +               if (!IS_ERR(hcd->gen_phy)) {
> +                       ret = phy_calibrate(hcd->gen_phy);
> +                       if (ret < 0 && ret != -ENOTSUPP)
> +                               dev_err(hcd->self.controller,
> +                                       "failed to calibrate USB PHY\n");
> +               }
> +       }

Here as well, is it really necessary to special-case it so much? I'd
say if there is a PHY and it has a calibrate function bound we call
it, and if not we just go ahead.

I also think that this would fit better in core/hcd.c since it's not
really XHCI specific... it's conceivable that an EHCI controller might
also need to tune some PHY settings after reset (in fact Tegra does
something similar, although it already has another hack for that now),
so if we introduce this general facility why not offer it to
everyone?.

> +
> +       return ret;
>  }
>
>  static int xhci_plat_start(struct usb_hcd *hcd)
> @@ -288,8 +308,23 @@ static int xhci_plat_resume(struct device *dev)
>  {
>         struct usb_hcd  *hcd = dev_get_drvdata(dev);
>         struct xhci_hcd *xhci = hcd_to_xhci(hcd);
> +       int ret;
> +
> +       ret = xhci_resume(xhci, 0);
> +       if (ret)
> +               return ret;
>
> -       return xhci_resume(xhci, 0);
> +       if (of_device_is_compatible(dev->parent->of_node, "synopsys,dwc3") ||
> +           of_device_is_compatible(dev->parent->of_node, "snps,dwc3")) {
> +               if (!IS_ERR(hcd->gen_phy)) {
> +                       ret = phy_calibrate(hcd->gen_phy);
> +                       if (ret < 0 && ret != -ENOTSUPP)
> +                               dev_err(hcd->self.controller,
> +                                       "failed to calibrate USB PHY\n");
> +               }
> +       }
> +
> +       return ret;
>  }
>
>  static const struct dev_pm_ops xhci_plat_pm_ops = {
> --
> 1.7.10.4
>
--
To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Vivek Gautam July 11, 2014, 3:48 a.m. UTC | #2
On Wed, Jul 9, 2014 at 11:28 PM, Julius Werner <jwerner@chromium.org> wrote:
> On Wed, Jul 9, 2014 at 3:01 AM, Vivek Gautam <gautam.vivek@samsung.com> wrote:
>> Some quirky PHYs may require to be calibrated post the host
>> controller initialization.
>> The USB 3.0 DRD PHY on Exynos5420/5800 systems, coming along with
>> Synopsys's DWC3 controller, is one such PHY which needs to be
>> calibrated post xhci's reset at initialization time and at
>> resume time, to get the controller work at SuperSpeed.
>>
>> Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
>> ---
>>  drivers/usb/host/xhci-plat.c |   39 +++++++++++++++++++++++++++++++++++++--
>>  1 file changed, 37 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
>> index e50bd7d..decf349 100644
>> --- a/drivers/usb/host/xhci-plat.c
>> +++ b/drivers/usb/host/xhci-plat.c
>> @@ -35,7 +35,27 @@ static void xhci_plat_quirks(struct device *dev, struct xhci_hcd *xhci)
>>  /* called during probe() after chip reset completes */
>>  static int xhci_plat_setup(struct usb_hcd *hcd)
>>  {
>> -       return xhci_gen_setup(hcd, xhci_plat_quirks);
>> +       struct device *parent;
>> +       int ret;
>> +
>> +       ret = xhci_gen_setup(hcd, xhci_plat_quirks);
>> +       if (ret) {
>> +               dev_err(hcd->self.controller, "xhci setup failed\n");
>> +               return ret;
>> +       }
>> +
>> +       parent = hcd->self.controller->parent;
>> +       if (of_device_is_compatible(parent->of_node, "synopsys,dwc3") ||
>> +           of_device_is_compatible(parent->of_node, "snps,dwc3")) {
>> +               if (!IS_ERR(hcd->gen_phy)) {
>> +                       ret = phy_calibrate(hcd->gen_phy);
>> +                       if (ret < 0 && ret != -ENOTSUPP)
>> +                               dev_err(hcd->self.controller,
>> +                                       "failed to calibrate USB PHY\n");
>> +               }
>> +       }
>
> Here as well, is it really necessary to special-case it so much? I'd
> say if there is a PHY and it has a calibrate function bound we call
> it, and if not we just go ahead.
>
> I also think that this would fit better in core/hcd.c since it's not
> really XHCI specific... it's conceivable that an EHCI controller might
> also need to tune some PHY settings after reset (in fact Tegra does
> something similar, although it already has another hack for that now),
> so if we introduce this general facility why not offer it to
> everyone?.

True, lets move it to core/hcd.c to make the entire calibration thing
more generic.

>
>> +
>> +       return ret;
>>  }
>>
>>  static int xhci_plat_start(struct usb_hcd *hcd)
>> @@ -288,8 +308,23 @@ static int xhci_plat_resume(struct device *dev)
>>  {
>>         struct usb_hcd  *hcd = dev_get_drvdata(dev);
>>         struct xhci_hcd *xhci = hcd_to_xhci(hcd);
>> +       int ret;
>> +
>> +       ret = xhci_resume(xhci, 0);
>> +       if (ret)
>> +               return ret;
>>
>> -       return xhci_resume(xhci, 0);
>> +       if (of_device_is_compatible(dev->parent->of_node, "synopsys,dwc3") ||
>> +           of_device_is_compatible(dev->parent->of_node, "snps,dwc3")) {
>> +               if (!IS_ERR(hcd->gen_phy)) {
>> +                       ret = phy_calibrate(hcd->gen_phy);
>> +                       if (ret < 0 && ret != -ENOTSUPP)
>> +                               dev_err(hcd->self.controller,
>> +                                       "failed to calibrate USB PHY\n");
>> +               }
>> +       }
>> +
>> +       return ret;
>>  }
>>
>>  static const struct dev_pm_ops xhci_plat_pm_ops = {
>> --
>> 1.7.10.4
>>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-usb" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index e50bd7d..decf349 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -35,7 +35,27 @@  static void xhci_plat_quirks(struct device *dev, struct xhci_hcd *xhci)
 /* called during probe() after chip reset completes */
 static int xhci_plat_setup(struct usb_hcd *hcd)
 {
-	return xhci_gen_setup(hcd, xhci_plat_quirks);
+	struct device *parent;
+	int ret;
+
+	ret = xhci_gen_setup(hcd, xhci_plat_quirks);
+	if (ret) {
+		dev_err(hcd->self.controller, "xhci setup failed\n");
+		return ret;
+	}
+
+	parent = hcd->self.controller->parent;
+	if (of_device_is_compatible(parent->of_node, "synopsys,dwc3") ||
+	    of_device_is_compatible(parent->of_node, "snps,dwc3")) {
+		if (!IS_ERR(hcd->gen_phy)) {
+			ret = phy_calibrate(hcd->gen_phy);
+			if (ret < 0 && ret != -ENOTSUPP)
+				dev_err(hcd->self.controller,
+					"failed to calibrate USB PHY\n");
+		}
+	}
+
+	return ret;
 }
 
 static int xhci_plat_start(struct usb_hcd *hcd)
@@ -288,8 +308,23 @@  static int xhci_plat_resume(struct device *dev)
 {
 	struct usb_hcd	*hcd = dev_get_drvdata(dev);
 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
+	int ret;
+
+	ret = xhci_resume(xhci, 0);
+	if (ret)
+		return ret;
 
-	return xhci_resume(xhci, 0);
+	if (of_device_is_compatible(dev->parent->of_node, "synopsys,dwc3") ||
+	    of_device_is_compatible(dev->parent->of_node, "snps,dwc3")) {
+		if (!IS_ERR(hcd->gen_phy)) {
+			ret = phy_calibrate(hcd->gen_phy);
+			if (ret < 0 && ret != -ENOTSUPP)
+				dev_err(hcd->self.controller,
+					"failed to calibrate USB PHY\n");
+		}
+	}
+
+	return ret;
 }
 
 static const struct dev_pm_ops xhci_plat_pm_ops = {