Re: [PATCH v2 10/10] usb: chipidea: tegra: Add USB_TEGRA_PHY module to driver's dependencies

[Dmitry Osipenko <digetx@gmail.com>]

24.12.2019 00:32, Michał Mirosław пишет:
> On Fri, Dec 20, 2019 at 07:31:08AM +0300, Dmitry Osipenko wrote:
>> 20.12.2019 06:56, Peter Chen пишет:
>>> On 19-12-20 04:52:38, Dmitry Osipenko wrote:
> [...]
>>>> --- a/drivers/usb/chipidea/ci_hdrc_tegra.c
>>>> +++ b/drivers/usb/chipidea/ci_hdrc_tegra.c
>>>> @@ -53,6 +53,12 @@ static int tegra_udc_probe(struct platform_device *pdev)
>>>>  	struct tegra_udc *udc;
>>>>  	int err;
>>>>  
>>>> +	if (IS_MODULE(CONFIG_USB_TEGRA_PHY)) {
>>>> +		err = request_module("phy_tegra_usb");
>>>> +		if (err)
>>>> +			return err;
>>>> +	}
>>>> +
>>>
>>> Why you do this dependency, if this controller driver can't
>>> get USB PHY, it should return error. What's the return value
>>> after calling below:
>>>
>>> 	udc->phy = devm_usb_get_phy_by_phandle(&pdev->dev, "nvidia,phy", 0);
>>
>> It returns -EPROBE_DEFER when phy_tegra_usb isn't loaded.
> 
> How are other driver modules autoloaded? Isn't there an appropriate
> MODALIAS or MODULE_DEVICE_TABLE in there?

Hello Michał,

The phy_tegra_usb module is fine by itself, it's getting autoloaded.

The problem is that ci_hdrc_tegra module depends on the phy_tegra_usb
module and thus the PHY module should be loaded before the CI module,
otherwise CI driver fails with the EPROBE_DEFER.