[linux-sunxi] [PATCH] musb: sunxi: Ignore VBus errors in host-only mode

Bin Liu binmlist at gmail.com
Mon Sep 14 12:06:41 PDT 2015


Hi,

On Mon, Sep 14, 2015 at 12:56 PM, Hans de Goede <hdegoede at redhat.com> wrote:
> Hi,
>
> On 14-09-15 19:53, Bin Liu wrote:
>
> <snip>
>
>>>> This is my first time looking at dts handling in drivers, so I might
>>>> be completely wrong, but I am thinking that since the controller node
>>>> links to the phy node, so the controller node is the parent of the phy
>>>> node, so if there is an of api can look it up?
>>>
>>>
>>>
>>> If the phy is a child of the controller, then yes this would work,
>>> but in the case of sunxi the phy is a built-in mmio mapped peripheral
>>> just like the controller, so they sit at the same level and have no
>>> parent child relation.
>>
>>
>> musb_dsps dts is the same.
>>
>> sun8i-a33.dtsi:
>>
>>      soc {
>>          usb_otg: {
>>              phys = <&usbphy 0>;
>>          }
>>          usbphy: {
>>          }
>>      }
>>
>> As in the example above, usb_otg node refers to usbphy node, so I am
>> wondering if there is an of api to look up the usb_otg properties in
>> the usbphy driver.
>
>
> That would boil down to hardcoding the node name / path compatible
> which is not acceptable from a devicetree pov.

Okay, I got this sorted out - querying dr_mode in the phy driver:

struct device_node *p;
struct device_node *t = NULL;
const char *dr_mode_str;
enum usb_dr_mode dr_mode;

do {
    t = of_find_node_with_property(t, "phys");
    if (!t)
        goto end;

    p = of_parse_phandle(t, "phys", 0);
    if (p == pdev->dev.of_node)
        break;
while (true);

of_property_read_string(t, "dr_mode", &dr_mode_str);
dr_mode = of_usb_get_dr_mode(dr_mode_str);

end:

Regards,
-Bin.

>
> Really having to duplicate the dr_mode is not that bad / such big
> a deal.
>
> Regards,
>
> Hans



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