Re: [PATCH v5 2/2] drm/tiny: add driver for Apple Touch Bars in x86 Macs

[Thomas Zimmermann <tzimmermann@suse.de>]

Hi

Am 25.02.25 um 12:01 schrieb andriy.shevchenko@linux.intel.com:
> On Tue, Feb 25, 2025 at 10:48:53AM +0000, Aditya Garg wrote:
>>> On 25 Feb 2025, at 4:17 PM, andriy.shevchenko@linux.intel.com wrote:
>>> On Tue, Feb 25, 2025 at 10:36:03AM +0000, Aditya Garg wrote:
>>>>>> On 25 Feb 2025, at 4:03 PM, andriy.shevchenko@linux.intel.com wrote:
>>>>> On Tue, Feb 25, 2025 at 10:09:42AM +0000, Aditya Garg wrote:
> ...
>
>>>>>> +static int appletbdrm_probe(struct usb_interface *intf,
>>>>>> +                const struct usb_device_id *id)
>>>>>> +{
>>>>>> +    struct usb_endpoint_descriptor *bulk_in, *bulk_out;
>>>>>> +    struct device *dev = &intf->dev;
>>>>>> +    struct appletbdrm_device *adev;
>>>>>> +    struct drm_device *drm;
>>>>>> +    int ret;
>>>>>> +
>>>>>> +    ret = usb_find_common_endpoints(intf->cur_altsetting, &bulk_in, &bulk_out, NULL, NULL);
>>>>>> +    if (ret) {
>>>>>> +        drm_err(drm, "Failed to find bulk endpoints\n");
>>>>> This is simply wrong (and in this case even lead to crash in some circumstances).
>>>>> drm_err() may not be used here. That's my point in previous discussions.
>>>>> Independently on the subsystem the ->probe() for the sake of consistency and
>>>>> being informative should only rely on struct device *dev,
>>>> I'm not sure how drm_err works,
>>> It's a macro.
>>>
>>>> but struct drm_device does have a struct device *dev as well.
>>> Yes, but only when it's initialized.
>>>
>>>> Anyways, this is something I'll leave for Thomas to reply.
>>> The code above is wrong independently on his reply :-)
>> I'm kinda stuck between contrasting views of 2 kernel maintainers lol,
>> so I said let Thomas reply.
> Sure. I also want him to clarify my question about potential drm_err_probe().

These threads get a little lengthy. What is the question?

Best regards
Thomas

>

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
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