On Tue, Feb 06, 2024 at 03:47:45PM +0100, Mike Looijmans wrote:
> On 06-02-2024 15:25, Mike Looijmans wrote:
> > On 06-02-2024 14:50, Andy Shevchenko wrote:
> > > On Tue, Feb 06, 2024 at 02:33:47PM +0100, Mike Looijmans wrote:
> > > > On 06-02-2024 13:57, Andy Shevchenko wrote:
> > > > > On Tue, Feb 06, 2024 at 07:58:18AM +0100, Mike Looijmans wrote:
...
> > > > > > + wasbusy = --priv->rdata_xfer_busy;
> > > > > Why preincrement? How would it be different from postincrement?
> > > > Maybe better write this as:
> > > >
> > > > --priv->rdata_xfer_busy;
> > > >
> > > > wasbusy = priv->rdata_xfer_busy;
> > > >
> > > > I want the value after decrementing it.
> > > Yes, looks more obvious.
> >
> > Having done that, and looking at it again, it's better to just eliminate
> > the local "wasbusy" altogether. More concise.
>
>
> This removes the decrement operator, so the method now looks like this:
>
>
> static void ads1298_rdata_release_busy_or_restart(struct ads1298_private
> *priv)
> {
> guard(spinlock_irqsave)(&priv->irq_busy_lock);
>
> if (priv->rdata_xfer_busy > 1) {
> /*
> * DRDY interrupt occurred before SPI completion. Start a new
> * SPI transaction now to retrieve the data that wasn't latched
> * into the ADS1298 chip's transfer buffer yet.
> */
> spi_async(priv->spi, &priv->rdata_msg);
> /*
> * If more than one DRDY took place, there was an overrun. Since
> * the sample is already lost, reset the counter to 1 so that
> * we will wait for a DRDY interrupt after this SPI transaction.
> */
> priv->rdata_xfer_busy = 1;
> } else {
> /* No pending data, wait for DRDY */
> priv->rdata_xfer_busy = 0;
> }
> }
Yep and it looks like you reinvented atomics :-)
atomic_t rdata_xfer_busy;
...
But it's up to you what to do with that.
Maybe Jonathan can advice something different.
--
With Best Regards,
Andy Shevchenko
