linux-kernel - Re: [PATCH v11] i2c: designware: fix controller is holding SCL low while ENABLE bit is disabled

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <lon3lijqcb5zpylqfni4xecjxbv6tlfn4kmyn3zwfkhajyiamw@g72c4r7fo2c6>
Date: Fri, 13 Sep 2024 10:52:38 +0200
From: Andi Shyti <andi.shyti@...nel.org>
To: Liu Kimriver/刘金河 <kimriver.liu@...ngine.com>
Cc: Andy Shevchenko <andy.shevchenko@...il.com>, 
	"jarkko.nikula@...ux.intel.com" <jarkko.nikula@...ux.intel.com>, 
	"andriy.shevchenko@...ux.intel.com" <andriy.shevchenko@...ux.intel.com>, 
	"mika.westerberg@...ux.intel.com" <mika.westerberg@...ux.intel.com>, "jsd@...ihalf.com" <jsd@...ihalf.com>, 
	"linux-i2c@...r.kernel.org" <linux-i2c@...r.kernel.org>, "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, 
	Andy Shevchenko <andy@...nel.org>
Subject: Re: [PATCH v11] i2c: designware: fix controller is holding SCL low
 while ENABLE bit is disabled

Hi Kimriver,

please, don't send v12 anymore, I will take care of these little
notes from Andy.

You did a great job at following up on all the reviews, thanks!

Andi

On Fri, Sep 13, 2024 at 08:31:18AM GMT, Liu Kimriver/刘金河 wrote:
> Hi Andy
>  
>   Subject:  [PATCH v11] i2c: designware: fix controller is holding SCL low while ENABLE bit is disabled
>   I will change the subject to：
>   Subject:  [PATCH v11] i2c: designware: fix controller is holding SCL low while the ENABLE bit is disabled
> 
> >-----Original Message-----
> >From: Andy Shevchenko <andy.shevchenko@...il.com> 
> >Sent: 2024年9月13日 15:41
> >To: Liu Kimriver/刘金河 <kimriver.liu@...ngine.com>
> >Cc: jarkko.nikula@...ux.intel.com; andriy.shevchenko@...ux.intel.com; mika.westerberg@...ux.intel.com; jsd@...ihalf.com; andi.shyti@...nel.org; linux-i2c@...r.kernel.org; linux-kernel@...r.kernel.org; Andy >Shevchenko <andy@...nel.org>
> >Subject: Re: [PATCH v11] i2c: designware: fix controller is holding SCL low while ENABLE bit is disabled
> 
> >On Fri, Sep 13, 2024 at 6:35 AM Kimriver Liu <kimriver.liu@...ngine.com> wrote:
> >>
> >> It was observed that issuing the ABORT bit (IC_ENABLE[1]) will not 
> >> work when IC_ENABLE is already disabled.
> >>
> >> Check if the ENABLE bit (IC_ENABLE[0]) is disabled when the controller 
> >> is holding SCL low. If the ENABLE bit is disabled, the software needs 
> >> to enable it before trying to issue the ABORT bit. otherwise, the 
> >> controller ignores any write to ABORT bit.
> >>
> >> These kernel logs show up whenever an I2C transaction is attempted 
> >> after this failure.
> >> i2c_designware e95e0000.i2c: timeout waiting for bus ready 
> >> i2c_designware e95e0000.i2c: timeout in disabling adapter
> >>
> >> The patch fixes the issue where the controller cannot be disabled 
> >> while SCL is held low if the ENABLE bit is already disabled.
> >
> >...
> >
> >> +                       /*Set ENABLE bit before setting ABORT*/
> 
>        /* Set ENABLE bit before setting ABORT */
> 
> >Missing spaces
> >
> >...
> 
> >> +/*
> >> + * This function waits controller idling before disabling I2C
> 
> >waits for controller
> 
>  + * This function waits for controller idling before disabling I2C
> 
> >> + * When the controller is not in the IDLE state,
> >> + * MST_ACTIVITY bit (IC_STATUS[5]) is set.
> >> + * Values:
> >> + * 0x1 (ACTIVE): Controller not idle
> >> + * 0x0 (IDLE): Controller is idle
> >> + * The function is called after returning the end of the current 
> >> + transfer
> >> + * Returns:
> 
> >> + * False when controller is in IDLE state.
> >> + * True when controller is in ACTIVE state.
> 
> >Yeah, I know that this is a copy of what I suggested, but if we going to amend, these should be with definite article
> 
> > * False when the controller is in the IDLE state.
> > * True when the controller is in the ACTIVE state.
> 
>  
> 
> >> + */
> 
> >...
> 
> >> +       return regmap_read_poll_timeout(dev->map, DW_IC_STATUS, status,
> >> +                                      !(status & DW_IC_STATUS_MASTER_ACTIVITY),
> >> +                                      1100, 20000) != 0;
> 
> >You broke the indentation again.
> 
> it has been indented and aligned from the web：
> https://lore.kernel.org/all/4ebc4e8882a52620cbca30f1bf25650cbc3723fb.1726197817.git.kimriver.liu@siengine.com/
> 
> Thanks！ 
> 
> >--
> ------------------------------------------
> Best Regards
> Kimriver Liu