Re: [PATCH v3 3/7] usb: mtu3: support ip-sleep wakeup for MT8183

From: Chunfeng Yun <chunfeng.yun@mediatek.com>
To: Guenter Roeck <linux@roeck-us.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>, <devicetree@vger.kernel.org>,
	Mathias Nyman <mathias.nyman@intel.com>,
	<linux-usb@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<linux-mediatek@lists.infradead.org>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH v3 3/7] usb: mtu3: support ip-sleep wakeup for MT8183
Date: Mon, 16 Sep 2019 13:45:47 +0800	[thread overview]
Message-ID: <1568612747.7317.72.camel@mhfsdcap03> (raw)
In-Reply-To: <20190911184453.GA2628@roeck-us.net>

On Wed, 2019-09-11 at 11:44 -0700, Guenter Roeck wrote:
> On Fri, Aug 30, 2019 at 03:40:50PM +0800, Chunfeng Yun wrote:
> > Support USB wakeup by ip-sleep mode for MT8183, it's similar to
> > MT8173
> > 
> > Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
> > ---
> > v3: changes micros define
> > 
> > v2: no changes
> > ---
> >  drivers/usb/mtu3/mtu3_host.c | 14 +++++++++++++-
> >  1 file changed, 13 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/usb/mtu3/mtu3_host.c b/drivers/usb/mtu3/mtu3_host.c
> > index c871b94f3e6f..4f8208885ebd 100644
> > --- a/drivers/usb/mtu3/mtu3_host.c
> > +++ b/drivers/usb/mtu3/mtu3_host.c
> > @@ -18,6 +18,12 @@
> >  #include "mtu3.h"
> >  #include "mtu3_dr.h"
> >  
> > +/* mt8183 etc */
> > +#define PERI_WK_CTRL0	0x20
> > +#define WC0_IS_C(x)	(((x) & 0xf) << 28)  /* cycle debounce */
> > +#define WC0_IS_P	BIT(12)	/* polarity */
> > +#define WC0_IS_EN	BIT(6)
> > +
> 
> For 64-bit builds, this results in:
> 
> drivers/usb/mtu3/mtu3_host.c: In function ‘ssusb_wakeup_ip_sleep_set’:
> ./include/linux/bits.h:6:19: warning:
> 	conversion from ‘long unsigned int’ to ‘u32’ {aka ‘unsigned int’}
> 	changes value from ‘18446744073441120320’ to ‘4026536000’ [-Woverflow]
> 
> since WC0_IS_C() is sign extended to 64 bit and then truncated.
Got it, thanks a lot

> 
> Observed with gcc 7.4.0 and 8.3.0.
> 
> Guenter
> 
> >  /* mt8173 etc */
> >  #define PERI_WK_CTRL1	0x4
> >  #define WC1_IS_C(x)	(((x) & 0xf) << 26)  /* cycle debounce */
> > @@ -30,7 +36,8 @@
> >  #define SSC_SPM_INT_EN		BIT(1)
> >  
> >  enum ssusb_uwk_vers {
> > -	SSUSB_UWK_V1 = 1,
> > +	SSUSB_UWK_V0 = 0,
> > +	SSUSB_UWK_V1,
> >  	SSUSB_UWK_V2,
> >  };
> >  
> > @@ -43,6 +50,11 @@ static void ssusb_wakeup_ip_sleep_set(struct ssusb_mtk *ssusb, bool enable)
> >  	u32 reg, msk, val;
> >  
> >  	switch (ssusb->uwk_vers) {
> > +	case SSUSB_UWK_V0:
> > +		reg = ssusb->uwk_reg_base + PERI_WK_CTRL0;
> > +		msk = WC0_IS_EN | WC0_IS_C(0xf) | WC0_IS_P;
> > +		val = enable ? (WC0_IS_EN | WC0_IS_C(0x8)) : 0;
> > +		break;
> >  	case SSUSB_UWK_V1:
> >  		reg = ssusb->uwk_reg_base + PERI_WK_CTRL1;
> >  		msk = WC1_IS_EN | WC1_IS_C(0xf) | WC1_IS_P;