On 8/12/2015 12:33 PM, Felipe Balbi wrote: > On Wed, Aug 12, 2015 at 07:06:09PM +0800, Yunzhi Li wrote: >> Hi , >> 在 2015/8/11 22:12, Felipe Balbi 写道: >>> Hi, >>> >>> On Tue, Aug 11, 2015 at 10:27:42AM +0800, Yunzhi Li wrote: >>>> We initiate dwc2 usb controller in BIOS, when kernel driver >>>> start-up we should reset AHB hclk domain to reset all AHB >>>> interface registers to default. Without this the FIFO value >>>> setting might be incorrect because calculating FIFO size need the >>>> power-on value of GRXFSIZ/GNPTXFSIZ/HPTXFSIZ registers. >>>> >>>> This patch could avoid warnning massage like in rk3288 platform: >>>> [ 2.074764] dwc2 ff580000.usb: 256 invalid for >>>> host_perio_tx_fifo_size. Check HW configuration. >>>> >>>> Signed-off-by: Yunzhi Li <lyz@xxxxxxxxxxxxxx> >>>> >>>> --- >>>> >>>> drivers/usb/dwc2/platform.c | 12 ++++++++++++ >>>> 1 file changed, 12 insertions(+) >>>> >>>> diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c >>>> index 9093530..3da21ab 100644 >>>> --- a/drivers/usb/dwc2/platform.c >>>> +++ b/drivers/usb/dwc2/platform.c >>>> @@ -42,6 +42,7 @@ >>>> #include <linux/of_device.h> >>>> #include <linux/mutex.h> >>>> #include <linux/platform_device.h> >>>> +#include <linux/reset.h> >>>> #include <linux/usb/of.h> >>>> @@ -165,6 +166,7 @@ static int dwc2_driver_probe(struct platform_device *dev) >>>> struct resource *res; >>>> struct phy *phy; >>>> struct usb_phy *uphy; >>>> + struct reset_control *rst; >>>> int retval; >>>> int irq; >>>> @@ -189,6 +191,16 @@ static int dwc2_driver_probe(struct platform_device *dev) >>>> hsotg->dev = &dev->dev; >>>> + /* AHB hclk domain reset, set all AHB interface registers to default */ >>>> + rst = devm_reset_control_get_optional(&dev->dev, "ahb_reset"); >>> why isn't this done in core so PCI systems can also make use of it ? >>> >> I have no ides about how to reset a PCI interface dwc2 controller, John >> could you please give some infomation about it ? >> Is it also needed for PCI interface dwc2 IP ? > > even on platform only, how do you know all users provide a ahb_reset > reset controller ? > Also where do you provide the ahb_reset? I don't see it as a property for dwc2. With regards to PCI, I'm also not sure how you'd accomplish something like this. But the platform I use at least doesn't need this. Regards, John -- 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
