diff mbox

[v7,1/2] usb: host: xhci-plat: Get PHYs for xhci's hcds

Message ID 1414761989-21088-2-git-send-email-gautam.vivek@samsung.com (mailing list archive)
State New, archived
Headers show

Commit Message

Vivek Gautam Oct. 31, 2014, 1:26 p.m. UTC
The host controller by itself may sometimes need to handle PHY
and re-initialize it to re-configure some of the PHY parameters
to get full support out of the PHY controller.
Therefore, facilitate getting the two possible PHYs, viz.
USB 2.0 type (UTMI+) and USB 3.0 type (PIPE3), and initialize them.

Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
---
 drivers/usb/host/xhci-plat.c |   74 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 74 insertions(+)

Comments

Sergei Shtylyov Oct. 31, 2014, 1:51 p.m. UTC | #1
Hello.

On 10/31/2014 4:26 PM, Vivek Gautam wrote:

> The host controller by itself may sometimes need to handle PHY
> and re-initialize it to re-configure some of the PHY parameters
> to get full support out of the PHY controller.
> Therefore, facilitate getting the two possible PHYs, viz.
> USB 2.0 type (UTMI+) and USB 3.0 type (PIPE3), and initialize them.

> Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
> ---
>   drivers/usb/host/xhci-plat.c |   74 ++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 74 insertions(+)

> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
> index 3d78b0c..5207d5b 100644
> --- a/drivers/usb/host/xhci-plat.c
> +++ b/drivers/usb/host/xhci-plat.c
[...]
> @@ -129,10 +130,41 @@ static int xhci_plat_probe(struct platform_device *pdev)
>   			goto put_hcd;
>   	}
>
> +	/* Get possile USB 2.0 type PHY (UTMI+) available with xhci */
> +	hcd->phy = devm_phy_get(&pdev->dev, "usb2-phy");
> +	if (IS_ERR(hcd->phy)) {
> +		ret = PTR_ERR(hcd->phy);
> +		if (ret == -EPROBE_DEFER) {
> +			goto disable_clk;
> +		} else if (ret != -ENOSYS && ret != -ENODEV) {

    Asking to be a *switch* statement instead...

> +			hcd->phy = NULL;
> +			dev_warn(&pdev->dev,
> +				 "Error retrieving usb2 phy: %d\n", ret);
> +		}
> +	}
> +
[...]
> @@ -158,12 +190,41 @@ static int xhci_plat_probe(struct platform_device *pdev)
>   	if (HCC_MAX_PSA(xhci->hcc_params) >= 4)
>   		xhci->shared_hcd->can_do_streams = 1;
>
> +	/* Get possile USB 3.0 type PHY (PIPE3) available with xhci */
> +	xhci->shared_hcd->phy = devm_phy_get(&pdev->dev, "usb3-phy");
> +	if (IS_ERR(xhci->shared_hcd->phy)) {
> +		ret = PTR_ERR(xhci->shared_hcd->phy);
> +		if (ret == -EPROBE_DEFER) {
> +			goto put_usb3_hcd;
> +		} else if (ret != -ENOSYS && ret != -ENODEV) {

    Likewise...

> +			xhci->shared_hcd->phy = NULL;
> +			dev_warn(&pdev->dev,
> +				 "Error retrieving usb3 phy: %d\n", ret);
> +		}
> +	}
> +
[...]
> @@ -204,6 +271,8 @@ static int xhci_plat_suspend(struct device *dev)
>   	struct usb_hcd	*hcd = dev_get_drvdata(dev);
>   	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
>
> +	phy_exit(hcd->phy);

    Hm, in the suspend() method?

> +
>   	return xhci_suspend(xhci);
>   }
>
[...]

WBR, Sergei
Vivek Gautam Nov. 17, 2014, 6:36 a.m. UTC | #2
Hi,


On Fri, Oct 31, 2014 at 7:21 PM, Sergei Shtylyov
<sergei.shtylyov@cogentembedded.com> wrote:
> Hello.
>
> On 10/31/2014 4:26 PM, Vivek Gautam wrote:
>
>> The host controller by itself may sometimes need to handle PHY
>> and re-initialize it to re-configure some of the PHY parameters
>> to get full support out of the PHY controller.
>> Therefore, facilitate getting the two possible PHYs, viz.
>> USB 2.0 type (UTMI+) and USB 3.0 type (PIPE3), and initialize them.
>
>
>> Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
>> ---
>>   drivers/usb/host/xhci-plat.c |   74
>> ++++++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 74 insertions(+)
>
>
>> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
>> index 3d78b0c..5207d5b 100644
>> --- a/drivers/usb/host/xhci-plat.c
>> +++ b/drivers/usb/host/xhci-plat.c
>
> [...]
>>
>> @@ -129,10 +130,41 @@ static int xhci_plat_probe(struct platform_device
>> *pdev)
>>                         goto put_hcd;
>>         }
>>
>> +       /* Get possile USB 2.0 type PHY (UTMI+) available with xhci */
>> +       hcd->phy = devm_phy_get(&pdev->dev, "usb2-phy");
>> +       if (IS_ERR(hcd->phy)) {
>> +               ret = PTR_ERR(hcd->phy);
>> +               if (ret == -EPROBE_DEFER) {
>> +                       goto disable_clk;
>> +               } else if (ret != -ENOSYS && ret != -ENODEV) {
>
>
>    Asking to be a *switch* statement instead...

Sure, will change this to *switch* statement. That will improve the
readability.

>
>> +                       hcd->phy = NULL;
>> +                       dev_warn(&pdev->dev,
>> +                                "Error retrieving usb2 phy: %d\n", ret);
>> +               }
>> +       }
>> +
>
> [...]
>>
>> @@ -158,12 +190,41 @@ static int xhci_plat_probe(struct platform_device
>> *pdev)
>>         if (HCC_MAX_PSA(xhci->hcc_params) >= 4)
>>                 xhci->shared_hcd->can_do_streams = 1;
>>
>> +       /* Get possile USB 3.0 type PHY (PIPE3) available with xhci */
>> +       xhci->shared_hcd->phy = devm_phy_get(&pdev->dev, "usb3-phy");
>> +       if (IS_ERR(xhci->shared_hcd->phy)) {
>> +               ret = PTR_ERR(xhci->shared_hcd->phy);
>> +               if (ret == -EPROBE_DEFER) {
>> +                       goto put_usb3_hcd;
>> +               } else if (ret != -ENOSYS && ret != -ENODEV) {
>
>
>    Likewise...

ok

>
>> +                       xhci->shared_hcd->phy = NULL;
>> +                       dev_warn(&pdev->dev,
>> +                                "Error retrieving usb3 phy: %d\n", ret);
>> +               }
>> +       }
>> +
>
> [...]
>>
>> @@ -204,6 +271,8 @@ static int xhci_plat_suspend(struct device *dev)
>>         struct usb_hcd  *hcd = dev_get_drvdata(dev);
>>         struct xhci_hcd *xhci = hcd_to_xhci(hcd);
>>
>> +       phy_exit(hcd->phy);
>
>
>    Hm, in the suspend() method?

phy_exit() should eventually be suspending the PHY and put it to
low power state.
phy_init() in resume() will then take up the task of activating the
PHY again.

phy_power_on() and phy_power_off() are called at xhci_probe() and remove() time.

Does this makes sense ?
Vivek Gautam Nov. 17, 2014, 6:38 a.m. UTC | #3
Hi Felipe,



On Fri, Oct 31, 2014 at 6:56 PM, Vivek Gautam <gautam.vivek@samsung.com> wrote:
> The host controller by itself may sometimes need to handle PHY
> and re-initialize it to re-configure some of the PHY parameters
> to get full support out of the PHY controller.
> Therefore, facilitate getting the two possible PHYs, viz.
> USB 2.0 type (UTMI+) and USB 3.0 type (PIPE3), and initialize them.
>
> Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
> ---
>  drivers/usb/host/xhci-plat.c |   74 ++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 74 insertions(+)
>
> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
> index 3d78b0c..5207d5b 100644
> --- a/drivers/usb/host/xhci-plat.c
> +++ b/drivers/usb/host/xhci-plat.c
> @@ -16,6 +16,7 @@
>  #include <linux/module.h>
>  #include <linux/of.h>
>  #include <linux/platform_device.h>
> +#include <linux/phy/phy.h>
>  #include <linux/slab.h>
>  #include <linux/usb/xhci_pdriver.h>
>
> @@ -129,10 +130,41 @@ static int xhci_plat_probe(struct platform_device *pdev)
>                         goto put_hcd;
>         }
>
> +       /* Get possile USB 2.0 type PHY (UTMI+) available with xhci */
> +       hcd->phy = devm_phy_get(&pdev->dev, "usb2-phy");
> +       if (IS_ERR(hcd->phy)) {
> +               ret = PTR_ERR(hcd->phy);
> +               if (ret == -EPROBE_DEFER) {
> +                       goto disable_clk;
> +               } else if (ret != -ENOSYS && ret != -ENODEV) {
> +                       hcd->phy = NULL;
> +                       dev_warn(&pdev->dev,
> +                                "Error retrieving usb2 phy: %d\n", ret);
> +               }
> +       }
> +
>         ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
>         if (ret)
>                 goto disable_clk;
>
> +       /*
> +        * Initialize and power-on USB 2.0 PHY
> +        * FIXME: Isn't this a hacky way of initializing the PHY again ?
> +        * xhci's parent would have already initialized the PHY, but we
> +        * wanna do it again.
> +        */

Does this change looks anywhere close to what you suggested to
re-initialize PHYs in XHCI even after DWC3 has initialized them once,
in order to avoid adding phy_calibration() callback ? ;-)

> +       hcd->phy->init_count = 0;
> +       ret = phy_init(hcd->phy);
> +       if (ret)
> +               goto dealloc_usb2_hcd;
> +
> +       hcd->phy->power_count = 0;
> +       ret = phy_power_on(hcd->phy);
> +       if (ret) {
> +               phy_exit(hcd->phy);
> +               goto dealloc_usb2_hcd;
> +       }
> +
>         device_wakeup_enable(hcd->self.controller);
>
>         /* USB 2.0 roothub is stored in the platform_device now. */
> @@ -158,12 +190,41 @@ static int xhci_plat_probe(struct platform_device *pdev)
>         if (HCC_MAX_PSA(xhci->hcc_params) >= 4)
>                 xhci->shared_hcd->can_do_streams = 1;
>
> +       /* Get possile USB 3.0 type PHY (PIPE3) available with xhci */
> +       xhci->shared_hcd->phy = devm_phy_get(&pdev->dev, "usb3-phy");
> +       if (IS_ERR(xhci->shared_hcd->phy)) {
> +               ret = PTR_ERR(xhci->shared_hcd->phy);
> +               if (ret == -EPROBE_DEFER) {
> +                       goto put_usb3_hcd;
> +               } else if (ret != -ENOSYS && ret != -ENODEV) {
> +                       xhci->shared_hcd->phy = NULL;
> +                       dev_warn(&pdev->dev,
> +                                "Error retrieving usb3 phy: %d\n", ret);
> +               }
> +       }
> +
>         ret = usb_add_hcd(xhci->shared_hcd, irq, IRQF_SHARED);
>         if (ret)
>                 goto put_usb3_hcd;
>
> +       /* Initialize and power-on USB 3.0 PHY */
> +       xhci->shared_hcd->phy->init_count = 0;
> +       ret = phy_init(xhci->shared_hcd->phy);
> +       if (ret)
> +               goto dealloc_usb3_hcd;
> +
> +       xhci->shared_hcd->phy->power_count = 0;
> +       ret = phy_power_on(xhci->shared_hcd->phy);
> +       if (ret) {
> +               phy_exit(xhci->shared_hcd->phy);
> +               goto dealloc_usb3_hcd;
> +       }
> +
>         return 0;
>
> +dealloc_usb3_hcd:
> +       usb_remove_hcd(xhci->shared_hcd);
> +
>  put_usb3_hcd:
>         usb_put_hcd(xhci->shared_hcd);
>
> @@ -186,9 +247,15 @@ static int xhci_plat_remove(struct platform_device *dev)
>         struct xhci_hcd *xhci = hcd_to_xhci(hcd);
>         struct clk *clk = xhci->clk;
>
> +       phy_power_off(xhci->shared_hcd->phy);
> +       phy_exit(xhci->shared_hcd->phy);
> +
>         usb_remove_hcd(xhci->shared_hcd);
>         usb_put_hcd(xhci->shared_hcd);
>
> +       phy_power_off(hcd->phy);
> +       phy_exit(hcd->phy);
> +
>         usb_remove_hcd(hcd);
>         if (!IS_ERR(clk))
>                 clk_disable_unprepare(clk);
> @@ -204,6 +271,8 @@ static int xhci_plat_suspend(struct device *dev)
>         struct usb_hcd  *hcd = dev_get_drvdata(dev);
>         struct xhci_hcd *xhci = hcd_to_xhci(hcd);
>
> +       phy_exit(hcd->phy);
> +
>         return xhci_suspend(xhci);
>  }
>
> @@ -211,6 +280,11 @@ 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 = phy_init(hcd->phy);
> +       if (ret)
> +               return ret;
>
>         return xhci_resume(xhci, 0);
>  }
> --
> 1.7.10.4
>
Sergei Shtylyov Nov. 17, 2014, 4:16 p.m. UTC | #4
Hello.

On 11/17/2014 9:36 AM, Vivek Gautam wrote:

>>> The host controller by itself may sometimes need to handle PHY
>>> and re-initialize it to re-configure some of the PHY parameters
>>> to get full support out of the PHY controller.
>>> Therefore, facilitate getting the two possible PHYs, viz.
>>> USB 2.0 type (UTMI+) and USB 3.0 type (PIPE3), and initialize them.

>>> Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
>>> ---
>>>    drivers/usb/host/xhci-plat.c |   74
>>> ++++++++++++++++++++++++++++++++++++++++++
>>>    1 file changed, 74 insertions(+)

>>> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
>>> index 3d78b0c..5207d5b 100644
>>> --- a/drivers/usb/host/xhci-plat.c
>>> +++ b/drivers/usb/host/xhci-plat.c
[...]
>>> @@ -204,6 +271,8 @@ static int xhci_plat_suspend(struct device *dev)
>>>          struct usb_hcd  *hcd = dev_get_drvdata(dev);
>>>          struct xhci_hcd *xhci = hcd_to_xhci(hcd);
>>>
>>> +       phy_exit(hcd->phy);

>>     Hm, in the suspend() method?

> phy_exit() should eventually be suspending the PHY and put it to
> low power state.

    I thought it's a role that the power_off() mothod should play, considering 
that the power_on() method gets called after the init() method....

> phy_init() in resume() will then take up the task of activating the
> PHY again.

> phy_power_on() and phy_power_off() are called at xhci_probe() and remove() time.

    Of course.

> Does this makes sense ?

    Not much, really.

WBR, Sergei
Vivek Gautam Nov. 18, 2014, 12:20 p.m. UTC | #5
On Mon, Nov 17, 2014 at 9:46 PM, Sergei Shtylyov
<sergei.shtylyov@cogentembedded.com> wrote:
> Hello.
>
> On 11/17/2014 9:36 AM, Vivek Gautam wrote:
>
>>>> The host controller by itself may sometimes need to handle PHY
>>>> and re-initialize it to re-configure some of the PHY parameters
>>>> to get full support out of the PHY controller.
>>>> Therefore, facilitate getting the two possible PHYs, viz.
>>>> USB 2.0 type (UTMI+) and USB 3.0 type (PIPE3), and initialize them.
>
>
>>>> Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
>>>> ---
>>>>    drivers/usb/host/xhci-plat.c |   74
>>>> ++++++++++++++++++++++++++++++++++++++++++
>>>>    1 file changed, 74 insertions(+)
>
>
>>>> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
>>>> index 3d78b0c..5207d5b 100644
>>>> --- a/drivers/usb/host/xhci-plat.c
>>>> +++ b/drivers/usb/host/xhci-plat.c
>
> [...]
>>>>
>>>> @@ -204,6 +271,8 @@ static int xhci_plat_suspend(struct device *dev)
>>>>          struct usb_hcd  *hcd = dev_get_drvdata(dev);
>>>>          struct xhci_hcd *xhci = hcd_to_xhci(hcd);
>>>>
>>>> +       phy_exit(hcd->phy);
>
>
>>>     Hm, in the suspend() method?
>
>
>> phy_exit() should eventually be suspending the PHY and put it to
>> low power state.
>
>
>    I thought it's a role that the power_off() mothod should play,
> considering that the power_on() method gets called after the init()
> method....

phy_power_off() should be cutting the clocks and power from PHY
completely, no ?
In that case one may not be able to wakeup the system from USB.

So phy_exit() gets the responsibility to put the PHY into low power state.

Ccing Kishon also to get his opinion on actual role of the two callbacks -
phy_init/exit() and phy_power_on/off().

>
>> phy_init() in resume() will then take up the task of activating the
>> PHY again.
>
>
>> phy_power_on() and phy_power_off() are called at xhci_probe() and remove()
>> time.
>
>
>    Of course.
>
>> Does this makes sense ?
>
>
>    Not much, really.
>
> WBR, Sergei
>
diff mbox

Patch

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 3d78b0c..5207d5b 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -16,6 +16,7 @@ 
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/phy/phy.h>
 #include <linux/slab.h>
 #include <linux/usb/xhci_pdriver.h>
 
@@ -129,10 +130,41 @@  static int xhci_plat_probe(struct platform_device *pdev)
 			goto put_hcd;
 	}
 
+	/* Get possile USB 2.0 type PHY (UTMI+) available with xhci */
+	hcd->phy = devm_phy_get(&pdev->dev, "usb2-phy");
+	if (IS_ERR(hcd->phy)) {
+		ret = PTR_ERR(hcd->phy);
+		if (ret == -EPROBE_DEFER) {
+			goto disable_clk;
+		} else if (ret != -ENOSYS && ret != -ENODEV) {
+			hcd->phy = NULL;
+			dev_warn(&pdev->dev,
+				 "Error retrieving usb2 phy: %d\n", ret);
+		}
+	}
+
 	ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
 	if (ret)
 		goto disable_clk;
 
+	/*
+	 * Initialize and power-on USB 2.0 PHY
+	 * FIXME: Isn't this a hacky way of initializing the PHY again ?
+	 * xhci's parent would have already initialized the PHY, but we
+	 * wanna do it again.
+	 */
+	hcd->phy->init_count = 0;
+	ret = phy_init(hcd->phy);
+	if (ret)
+		goto dealloc_usb2_hcd;
+
+	hcd->phy->power_count = 0;
+	ret = phy_power_on(hcd->phy);
+	if (ret) {
+		phy_exit(hcd->phy);
+		goto dealloc_usb2_hcd;
+	}
+
 	device_wakeup_enable(hcd->self.controller);
 
 	/* USB 2.0 roothub is stored in the platform_device now. */
@@ -158,12 +190,41 @@  static int xhci_plat_probe(struct platform_device *pdev)
 	if (HCC_MAX_PSA(xhci->hcc_params) >= 4)
 		xhci->shared_hcd->can_do_streams = 1;
 
+	/* Get possile USB 3.0 type PHY (PIPE3) available with xhci */
+	xhci->shared_hcd->phy = devm_phy_get(&pdev->dev, "usb3-phy");
+	if (IS_ERR(xhci->shared_hcd->phy)) {
+		ret = PTR_ERR(xhci->shared_hcd->phy);
+		if (ret == -EPROBE_DEFER) {
+			goto put_usb3_hcd;
+		} else if (ret != -ENOSYS && ret != -ENODEV) {
+			xhci->shared_hcd->phy = NULL;
+			dev_warn(&pdev->dev,
+				 "Error retrieving usb3 phy: %d\n", ret);
+		}
+	}
+
 	ret = usb_add_hcd(xhci->shared_hcd, irq, IRQF_SHARED);
 	if (ret)
 		goto put_usb3_hcd;
 
+	/* Initialize and power-on USB 3.0 PHY */
+	xhci->shared_hcd->phy->init_count = 0;
+	ret = phy_init(xhci->shared_hcd->phy);
+	if (ret)
+		goto dealloc_usb3_hcd;
+
+	xhci->shared_hcd->phy->power_count = 0;
+	ret = phy_power_on(xhci->shared_hcd->phy);
+	if (ret) {
+		phy_exit(xhci->shared_hcd->phy);
+		goto dealloc_usb3_hcd;
+	}
+
 	return 0;
 
+dealloc_usb3_hcd:
+	usb_remove_hcd(xhci->shared_hcd);
+
 put_usb3_hcd:
 	usb_put_hcd(xhci->shared_hcd);
 
@@ -186,9 +247,15 @@  static int xhci_plat_remove(struct platform_device *dev)
 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
 	struct clk *clk = xhci->clk;
 
+	phy_power_off(xhci->shared_hcd->phy);
+	phy_exit(xhci->shared_hcd->phy);
+
 	usb_remove_hcd(xhci->shared_hcd);
 	usb_put_hcd(xhci->shared_hcd);
 
+	phy_power_off(hcd->phy);
+	phy_exit(hcd->phy);
+
 	usb_remove_hcd(hcd);
 	if (!IS_ERR(clk))
 		clk_disable_unprepare(clk);
@@ -204,6 +271,8 @@  static int xhci_plat_suspend(struct device *dev)
 	struct usb_hcd	*hcd = dev_get_drvdata(dev);
 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
 
+	phy_exit(hcd->phy);
+
 	return xhci_suspend(xhci);
 }
 
@@ -211,6 +280,11 @@  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 = phy_init(hcd->phy);
+	if (ret)
+		return ret;
 
 	return xhci_resume(xhci, 0);
 }