Re: [PATCH v2] iio: mcp320x: Fix occasional incorrect readings

[jic23]

Michael Welling writes: 

> On Thu, May 07, 2015 at 11:13:15AM +0100, Jonathan Cameron wrote:
> > On 06/05/15 17:49, Michael Welling wrote:
> > > Without the cacheline alignment, the readings will occasionally incorrectly
> > > return 0.
> > > 
> > > Signed-off-by: Michael Welling <mwelling@xxxxxxxx>
> > Applied to the fixes-togreg branch of iio.git.  Not sure
> > when I'll be able to push this out publicly as travelling
> > / working nights and generally having a silly week. 
> >
> > J
>
> Thanks. 
>
> Appearently code can be silly too:
> https://lkml.org/lkml/2015/5/7/879
*laughs*.  Hmm. 8.56pm. Chances are Mark was a beer or two down ;) 

> > > ---
> > > 
> > > v2: Moved buffers to the end of the mcp320x struct per suggestion to keep
> > > them on their own cacheline.
> > > 
> > >  drivers/iio/adc/mcp320x.c |    6 +++---
> > >  1 file changed, 3 insertions(+), 3 deletions(-)
> > > 
> > > diff --git a/drivers/iio/adc/mcp320x.c b/drivers/iio/adc/mcp320x.c
> > > index efbfd12..8d9c9b9 100644
> > > --- a/drivers/iio/adc/mcp320x.c
> > > +++ b/drivers/iio/adc/mcp320x.c
> > > @@ -60,12 +60,12 @@ struct mcp320x {
> > >  	struct spi_message msg;
> > >  	struct spi_transfer transfer[2];
> > >  
> > > -	u8 tx_buf;
> > > -	u8 rx_buf[2];
> > > -
> > >  	struct regulator *reg;
> > >  	struct mutex lock;
> > >  	const struct mcp320x_chip_info *chip_info;
> > > +
> > > +	u8 tx_buf ____cacheline_aligned;
> > > +	u8 rx_buf[2];
> > >  };
> > >  
> > >  static int mcp320x_channel_to_tx_data(int device_index,
> > >  
> --
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