Re: [PATCH v1 1/9] mfd: Add core driver for Nuvoton NCT6694

[Ming Yu <a0282524688@xxxxxxxxx>]

Dear Marc,

Excuse me, I'm a bit confused. Is there anything I need to
improve on?

Thanks,
Ming

Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> 於 2024年10月24日 週四 下午11:34寫道：
>
> On 24.10.2024 17:20:57, Marc Kleine-Budde wrote:
>
> [...]
>
> > > +   nct6694->cmd_buffer = devm_kcalloc(dev, CMD_PACKET_SZ,
> > > +                                      sizeof(unsigned char), GFP_KERNEL);
> > > +   if (!nct6694->cmd_buffer)
> > > +           return -ENOMEM;
> > > +   nct6694->rx_buffer = devm_kcalloc(dev, MAX_PACKET_SZ,
> > > +                                     sizeof(unsigned char), GFP_KERNEL);
> > > +   if (!nct6694->rx_buffer)
> > > +           return -ENOMEM;
> > > +   nct6694->tx_buffer = devm_kcalloc(dev, MAX_PACKET_SZ,
> > > +                                     sizeof(unsigned char), GFP_KERNEL);
> > > +   if (!nct6694->tx_buffer)
> > > +           return -ENOMEM;
> > > +   nct6694->int_buffer = devm_kcalloc(dev, MAX_PACKET_SZ,
> > > +                                      sizeof(unsigned char), GFP_KERNEL);
> > > +   if (!nct6694->int_buffer)
> > > +           return -ENOMEM;
> > > +
> > > +   nct6694->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
> > > +   if (!nct6694->int_in_urb) {
> > > +           dev_err(&udev->dev, "Failed to allocate INT-in urb!\n");
> > > +           return -ENOMEM;
> > > +   }
> > > +
> > > +   /* Bulk pipe maximum packet for each transaction */
> > > +   bulk_pipe = usb_sndbulkpipe(udev, BULK_OUT_ENDPOINT);
> > > +   nct6694->maxp = usb_maxpacket(udev, bulk_pipe);
> > > +
> > > +   mutex_init(&nct6694->access_lock);
> > > +   nct6694->udev = udev;
> > > +   nct6694->timeout = URB_TIMEOUT; /* Wait until urb complete */
> > > +
> > > +   INIT_LIST_HEAD(&nct6694->handler_list);
> > > +   spin_lock_init(&nct6694->lock);
> > > +
> > > +   usb_fill_int_urb(nct6694->int_in_urb, udev, pipe,
> > > +                    nct6694->int_buffer, maxp, usb_int_callback,
> > > +                    nct6694, int_endpoint->bInterval);
> > > +   ret = usb_submit_urb(nct6694->int_in_urb, GFP_KERNEL);
> > > +   if (ret)
> > > +           goto err_urb;
> > > +
> > > +   dev_set_drvdata(&udev->dev, nct6694);
> > > +   usb_set_intfdata(iface, nct6694);
> > > +
> > > +   ret = mfd_add_hotplug_devices(&udev->dev, nct6694_dev,
> > > +                                 ARRAY_SIZE(nct6694_dev));
> > > +   if (ret) {
> > > +           dev_err(&udev->dev, "Failed to add mfd's child device\n");
> > > +           goto err_mfd;
> > > +   }
> > > +
> > > +   nct6694->async_workqueue = alloc_ordered_workqueue("asyn_workqueue", 0);
> >
> > Where is the async_workqueue used?
>
> Sorry - it's used in the driver, which live in separate directories -
> you can ignore this comment.
>
> But then the question comes up, it looks racy to _first_ add the devices
> and _then_ the workqueue.
>
> regards,
> Marc
>
> --
> Pengutronix e.K.                 | Marc Kleine-Budde          |
> Embedded Linux                   | https://www.pengutronix.de |
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