Re: [PATCH v7] USB device driver of Topcliff PCH

["Toshiharu Okada" <toshiharu-linux@dsn.okisemi.com>]

Hi Michal

Thank you for your comment.
I will modify to "if-else-if-else" as follows.

-----------
if (!list_empty(&ep->queue)) {
    dev_dbg(&dev->pdev->dev, "%s: list not empty", __func__);
    ret = -EAGAIN;
} else {
    if (halt) { /* halt or clear halt */
        if (ep->num == PCH_UDC_EP0)
            ep->dev->stall = 1;
        pch_udc_ep_set_stall(ep);
        pch_udc_enable_ep_interrupts(ep->dev, PCH_UDC_EPINT(ep->in,
ep->num));
        ret = 0;
    } else {
        pch_udc_ep_clear_stall(ep);
        ret = 0;
    }
}
-------------

Best regards
Toshiharu Okada (OKI SEMICONDUCTOR)
-----
Date: Mon, 08 Nov 2010 12:22:51 +0100
From: "Michał Nazarewicz" <m.nazarewicz@samsung.com>
> On Wed, 03 Nov 2010 19:37:50 +0100, Andy Isaacson <adi@hexapodia.org>
wrote:
> > I think this would be clearer as
> >
> > + if (!list_empty(&ep->queue)) {
> > + dev_dbg(&dev->pdev->dev, "%s: list not empty", __func__);
> > + ret = -EAGAIN;
> > + }
> > + if (halt) {
> > + if (ep->num == PCH_UDC_EP0)
> > + ep->dev->stall = 1;
> > + pch_udc_ep_set_stall(ep);
> > + pch_udc_enable_ep_interrupts(ep->dev,
> > +      PCH_UDC_EPINT(ep->in, ep->num));
> > + ret = 0;
> > + } else {
> > + pch_udc_ep_clear_stall(ep);
> > + ret = 0;
> > + }
>
> This changes the behavior of the construct though.
>
> > because:
> > 1. if (!list_empty  is a standalone check, there is no if/else if/else
> > connection between list_empty() and halt.
>
> This depends on how you look at it.  The way I see it is that there are
three
> mutually exclusive cases: the list is not empty, it is a halt, it is not a
> halt.  This way, if-else-if-else seems like a good construct to me.
>
> > 2. I prefer if (foo) {} else {} instead of if (!foo) {} else {}, unless
> > there is a significant reason to do the negated test.
>
> I agree on that though.
>
> >> + pr_debug("%s: %s", __func__, usbep->name);
> >
> > There are probably too many pr_debug() and dev_dbg()s in this driver.
> > Please reconsider which ones are appropriate for mainline.
>
> Do we really care?  Just don't define DEBUG...
>
> -- 
> Best regards,                                        _     _
> | Humble Liege of Serenely Enlightened Majesty of  o' \,=./ `o
> | Computer Science,  Michał "mina86" Nazarewicz       (o o)
> +----[mina86*mina86.com]---[mina86*jabber.org]----ooO--(_)--Ooo--
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