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From:   Ping-Ke Shih <pkshih@realtek.com>
To:     Kevin Lo <kevlo@kevlo.org>, Kalle Valo <kvalo@kernel.org>
CC:     "linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>,
        Bitterblue Smith <rtl8821cerfe2@gmail.com>,
        Jes Sorensen <Jes.Sorensen@gmail.com>
Subject: RE: [PATCH v2] wifi: rtl8xxxu: 8188f: no need to initialize interrupts
Thread-Topic: [PATCH v2] wifi: rtl8xxxu: 8188f: no need to initialize
 interrupts
Thread-Index: AQHZeXnw1bVEGkPuTUKBTMt6fz5J1K9ANP9U//+JBgCABvhBIA==
Date:   Tue, 2 May 2023 09:10:04 +0000
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> -----Original Message-----
> From: Kevin Lo <kevlo@kevlo.org>
> Sent: Friday, April 28, 2023 2:35 PM
> To: Kalle Valo <kvalo@kernel.org>
> Cc: linux-wireless@vger.kernel.org; Bitterblue Smith <rtl8821cerfe2@gmail.com>; Jes Sorensen
> <Jes.Sorensen@gmail.com>; Ping-Ke Shih <pkshih@realtek.com>
> Subject: Re: [PATCH v2] wifi: rtl8xxxu: 8188f: no need to initialize interrupts
> 
> On Fri, Apr 28, 2023 at 08:40:34AM +0300, Kalle Valo wrote:
> >
> > Kevin Lo <kevlo@kevlo.org> writes:
> >
> > > There's no need to initialize interrupts for RTL8188FTV like the vendor driver.
> > >
> > > Signed-off-by: Kevin Lo <kevlo@kevlo.org>
> >
> > Why do this, what's the benefit? Or is this just a theoretical fix. The
> > commit log should explain this.
> 
> If I understand correctly, just like rtw88 usb devices, rtl8xxxu has no
> hardware interrupt.
> 

With/without hardware interrupt, it depends on IMR (interrupt mask register)
setting. If it is enabled, driver can receive C2H, PS indicators, and beacon
TBTT events via certain USB endpoint. But, normally vendor driver doesn't
use them neither.

Why it initializes interrupt in this patch is to reset ISR (interrupt status
register) to avoid unexpected interrupts are received. So, if it doesn't
really enable interrupt by IMR, I suppose it should work well even without
this patch.

Kevin, could I know the real problem you met?

Ping-Ke