Re: [PATCH 01/12] i2c: qup: fixed releasing dma without flush operation completion

[Abhishek Sahu]

On 2018-02-08 19:33, Sricharan R wrote:
> Hi Abhishek,
>
> On 2/3/2018 1:28 PM, Abhishek Sahu wrote:
> > The QUP BSLP BAM generates the following error sometimes if the
> > current I2C DMA transfer fails and the flush operation has been
> > scheduled
> >
> >     âbam-dma-engine 7884000.dma: Cannot free busy channelâ
> >
> > If any I2C error comes during BAM DMA transfer, then the QUP I2C
> > interrupt will be generated and the flush operation will be
> > carried out to make i2c consume all scheduled DMA transfer.
> > Currently, the same completion structure is being used for BAM
> > transfer which has already completed without reinit. It will make
> > flush operation wait_for_completion_timeout completed immediately
> > and will proceed for freeing the DMA resources where the
> > descriptors are still in process.
> >
> > Signed-off-by: Abhishek Sahu <absahu@xxxxxxxxxxxxxx>
> > ---
> >  drivers/i2c/busses/i2c-qup.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/i2c/busses/i2c-qup.c 
> > b/drivers/i2c/busses/i2c-qup.c
> > index 08f8e01..9faa26c41a 100644
> > --- a/drivers/i2c/busses/i2c-qup.c
> > +++ b/drivers/i2c/busses/i2c-qup.c
> > @@ -1,5 +1,5 @@
> >  /*
> > - * Copyright (c) 2009-2013, The Linux Foundation. All rights 
> > reserved.
> > + * Copyright (c) 2009-2013, 2016-2018, The Linux Foundation. All 
> > rights reserved.
>
> Not sure, if this was an intended change. But given that you are fixing 
> this,

 Thanks Sricharan.
 Since this is the first patch, so I updated the year.

> you can change the header to the new SPDX one.

 Yes that would be better.
 I will fix that also.

 Thanks,
 Abhishek

> >   * Copyright (c) 2014, Sony Mobile Communications AB.
> >   *
> >   *
> > @@ -844,6 +844,8 @@ static int qup_i2c_bam_do_xfer(struct qup_i2c_dev 
> > *qup, struct i2c_msg *msg,
> >  	}
> >
> >  	if (ret || qup->bus_err || qup->qup_err) {
> > +		reinit_completion(&qup->xfer);
> > +
> >  		if (qup_i2c_change_state(qup, QUP_RUN_STATE)) {
> >  			dev_err(qup->dev, "change to run state timed out");
> >  			goto desc_err;
>
> Except for the above nit,
>   Acked-by: Sricharan R <sricharan@xxxxxxxxxxxxxx>
>
> Regards,
>  Sricharan