[PATCH v3 2/2] usb: dwc3: Add support for usb3-phy PHY configuration

[Michal Simek]

Hi Jan,

On 4/25/22 11:47, Jan Kiszka wrote:
> On 09.03.22 10:05, Michal Simek wrote:
>> When usb3-phy label is found, PHY driver is called and serdes line is
>> initialized. This is preparation for serdes/psgtr driver to configure GT
>> lines based on description in DT.
>>
>> Signed-off-by: Michal Simek <michal.simek at xilinx.com>
>> ---
>>
>> Changes in v3:
>> - Add cover letter
>>
>> Changes in v2:
>> - Add missing header
>>
>>   drivers/usb/dwc3/dwc3-generic.c | 18 ++++++++++++++++++
>>   1 file changed, 18 insertions(+)
>>
>> diff --git a/drivers/usb/dwc3/dwc3-generic.c b/drivers/usb/dwc3/dwc3-generic.c
>> index 01bd0ca190e3..2c5205df62cd 100644
>> --- a/drivers/usb/dwc3/dwc3-generic.c
>> +++ b/drivers/usb/dwc3/dwc3-generic.c
>> @@ -14,6 +14,7 @@
>>   #include <dm/device-internal.h>
>>   #include <dm/lists.h>
>>   #include <dwc3-uboot.h>
>> +#include <generic-phy.h>
>>   #include <linux/bitops.h>
>>   #include <linux/delay.h>
>>   #include <linux/usb/ch9.h>
>> @@ -409,6 +410,17 @@ static int dwc3_glue_probe(struct udevice *dev)
>>   	struct udevice *child = NULL;
>>   	int index = 0;
>>   	int ret;
>> +	struct phy phy;
>> +
>> +	ret = generic_phy_get_by_name(dev, "usb3-phy", &phy);
>> +	if (!ret) {
>> +		ret = generic_phy_init(&phy);
>> +		if (ret)
>> +			return ret;
>> +	} else if (ret != -ENOENT) {
>> +		debug("could not get phy (err %d)\n", ret);
>> +		return ret;
>> +	}
>>   
>>   	glue->regs = dev_read_addr(dev);
>>   
>> @@ -420,6 +432,12 @@ static int dwc3_glue_probe(struct udevice *dev)
>>   	if (ret)
>>   		return ret;
>>   
>> +	if (phy.dev) {
>> +		ret = generic_phy_power_on(&phy);
>> +		if (ret)
>> +			return ret;
>> +	}
>> +
>>   	ret = device_find_first_child(dev, &child);
>>   	if (ret)
>>   		return ret;
> 
> Breaks USB on the iot2050-pg1 (am65x) - this one has NO usb3-phy:
> 
> ...
> starting USB...
> Bus usb at 10000: probe failed, error -61
> Bus usb at 10000: probe failed, error -61
> No working controllers found
> USB is stopped. Please issue 'usb start' first.
> starting USB...
> Bus usb at 10000: probe failed, error -61
> Bus usb at 10000: probe failed, error -61
> No working controllers found
> USB is stopped. Please issue 'usb start' first.
> starting USB...
> Bus usb at 10000: probe failed, error -61
> Bus usb at 10000: probe failed, error -61
> No working controllers found
> USB is stopped. Please issue 'usb start' first.
> 
> Is there anything that boards need to consider now?

-61 is ENODATA. I have looked at DT and there is no usb3-phy property. That's 
why generic_phy_get_by_name() can't return 0. Does it return -ENOENT?

Maybe it returns ENODATA and it should be also handled in else part.

Can you please enable debug and see?

Thanks,
Michal