Hi Andy
>-----Original Message-----
>From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
>Sent: 2024年9月11日 22:53
>To: Liu Kimriver/刘金河 <kimriver.liu@xxxxxxxxxxxx>
>Cc: jarkko.nikula@xxxxxxxxxxxxxxx; mika.westerberg@xxxxxxxxxxxxxxx; jsd@xxxxxxxxxxxx; andi.shyti@xxxxxxxxxx; linux-i2c@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
>Subject: Re: [PATCH v9] i2c: designware: fix controller is holding SCL low while ENABLE bit is disabled
>On Wed, Sep 11, 2024 at 05:45:05PM +0300, Andy Shevchenko wrote:
>> On Wed, Sep 11, 2024 at 04:39:45PM +0800, Kimriver Liu wrote:
>FWIW, below are the fixes
>
>...
>
>> > +/*
>> > + * This functions waits 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:
>>
>> > + * Return 0 as controller IDLE
>> > + * Return a negative errno as controller ACTIVE
>
> * False when controller is in IDLE state.
> * True when controller is in ACTIVE state.
>
>> But why non-boolean again?
>>
>> > + */
>> > +static int i2c_dw_is_controller_active(struct dw_i2c_dev *dev)
>
>static bool i2c_dw_is_controller_active(struct dw_i2c_dev *dev)
>
>> > +{
>> > + u32 status;
>> > +
>> > + regmap_read(dev->map, DW_IC_STATUS, &status);
>> > + if (!(status & DW_IC_STATUS_MASTER_ACTIVITY))
>> > + return 0;
>
> return false;
>
>> > + return regmap_read_poll_timeout(dev->map, DW_IC_STATUS, status,
>> > + !(status & DW_IC_STATUS_MASTER_ACTIVITY),
>> > + 1100, 20000);
>
> 1100, 20000) != 0;
>
>Alternatively
>
> int ret;
> ...
>
> ret = regmap_read_poll_timeout(dev->map, DW_IC_STATUS, status,
> !(status & DW_IC_STATUS_MASTER_ACTIVITY),
> 1100, 20000);
> if (ret)
> return true;
>
> return false;
>
> (Also mind indentation in _read_poll_timeout() lines.)
>
>> > +}
Sorry.
Thanks for your suggestions and scheme, I will update in patch v10 today.
------------------------------------------
Best Regards
Kimriver Liu
