[PATCH 4/4] usb: phy: omap-usb2: enable 960Mhz clock for omap5

ABRAHAM, KISHON VIJAY kishon at ti.com
Wed Sep 26 15:40:48 EST 2012


Hi,

On Wed, Sep 19, 2012 at 5:26 PM, Felipe Balbi <balbi at ti.com> wrote:
> On Wed, Sep 19, 2012 at 05:00:29PM +0530, Kishon Vijay Abraham I wrote:
>> "usb_otg_ss_refclk960m" is needed by usb2 phy present in omap5. For
>> omap4, the clk_get of this clock will fail since it does not have this
>> clock.
>>
>> Signed-off-by: Kishon Vijay Abraham I <kishon at ti.com>
>> ---
>>  Documentation/devicetree/bindings/usb/usb-phy.txt |    3 +++
>>  drivers/usb/phy/omap-usb2.c                       |   28 ++++++++++++++++++++-
>>  2 files changed, 30 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/devicetree/bindings/usb/usb-phy.txt b/Documentation/devicetree/bindings/usb/usb-phy.txt
>> index 7c5fd89..d5626de 100644
>> --- a/Documentation/devicetree/bindings/usb/usb-phy.txt
>> +++ b/Documentation/devicetree/bindings/usb/usb-phy.txt
>> @@ -24,6 +24,9 @@ Required properties:
>>  add the address of control module phy power register until a driver for
>>  control module is added
>>
>> +Optional properties:
>> + - has960mhzclk: should be added if the phy needs 960mhz clock
>> +
>>  This is usually a subnode of ocp2scp to which it is connected.
>>
>>  usb3phy at 4a084400 {
>> diff --git a/drivers/usb/phy/omap-usb2.c b/drivers/usb/phy/omap-usb2.c
>> index d36c282..d6612ba 100644
>> --- a/drivers/usb/phy/omap-usb2.c
>> +++ b/drivers/usb/phy/omap-usb2.c
>> @@ -146,6 +146,7 @@ static int __devinit omap_usb2_probe(struct platform_device *pdev)
>>       struct omap_usb                 *phy;
>>       struct usb_otg                  *otg;
>>       struct resource                 *res;
>> +     struct device_node              *np = pdev->dev.of_node;
>>
>>       phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);
>>       if (!phy) {
>> @@ -190,6 +191,15 @@ static int __devinit omap_usb2_probe(struct platform_device *pdev)
>>       }
>>       clk_prepare(phy->wkupclk);
>>
>> +     if (of_property_read_bool(np, "has960mhzclk")) {
>> +             phy->optclk = devm_clk_get(phy->dev, "usb_otg_ss_refclk960m");
>> +             if (IS_ERR(phy->optclk)) {
>> +                     dev_err(&pdev->dev, "unable to get refclk960m\n");
>> +                     return PTR_ERR(phy->optclk);
>> +             }
>> +             clk_prepare(phy->optclk);
>> +     }
>
> instead, can't you just always try to get the clock but ignore the error
> if it fails ?

This clock is needed for usb2 to work in dwc3 (omap5). So we have to
report the error in case we dont get the clock no?

Thanks
Kishon


More information about the devicetree-discuss mailing list