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: <971008d0fd32403198785e1e4543d108@siengine.com>
Date: Fri, 13 Sep 2024 08:31:18 +0000
From: Liu Kimriver/刘金河 <kimriver.liu@...ngine.com>
To: Andy Shevchenko <andy.shevchenko@...il.com>
CC: "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>,
        "andi.shyti@...nel.org"
	<andi.shyti@...nel.org>,
        "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 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