The interrupt will fire upon end of conversion. This currently can
happen in two situations: either the cnvst trigger was enabled and
toggled, or a single read was requested and the data is ready. The first
situation is already covered while the second is not. Instead, a waiting
delay is applied. Let's handle these interrupts more properly by adding
second path in our EOC helper.
Rename the interrupt handler to a more generic name as it won't only
handle triggered situations.
Signed-off-by: Miquel Raynal <[email protected]>
---
drivers/iio/adc/max1027.c | 31 ++++++++++++++++++++++++++++---
1 file changed, 28 insertions(+), 3 deletions(-)
diff --git a/drivers/iio/adc/max1027.c b/drivers/iio/adc/max1027.c
index b85fe0a48ff9..e734d32a5507 100644
--- a/drivers/iio/adc/max1027.c
+++ b/drivers/iio/adc/max1027.c
@@ -256,15 +256,27 @@ struct max1027_state {
struct iio_trigger *trig;
__be16 *buffer;
struct mutex lock;
+ struct completion complete;
u8 reg ____cacheline_aligned;
};
static int max1027_wait_eoc(struct iio_dev *indio_dev)
{
+ struct max1027_state *st = iio_priv(indio_dev);
unsigned int conversion_time = MAX1027_CONVERSION_UDELAY;
+ int ret;
- usleep_range(conversion_time, conversion_time * 2);
+ if (st->spi->irq) {
+ ret = wait_for_completion_timeout(&st->complete,
+ msecs_to_jiffies(1000));
+ if (!ret)
+ return ret;
+
+ reinit_completion(&st->complete);
+ } else {
+ usleep_range(conversion_time, conversion_time * 2);
+ }
return 0;
}
@@ -457,12 +469,24 @@ static int max1027_read_scan(struct iio_dev *indio_dev)
return 0;
}
-static irqreturn_t max1027_trigger_handler(int irq, void *private)
+static irqreturn_t max1027_threaded_handler(int irq, void *private)
{
struct iio_poll_func *pf = private;
struct iio_dev *indio_dev = pf->indio_dev;
+ struct max1027_state *st = iio_priv(indio_dev);
int ret;
+ /*
+ * When buffers are disabled, no trigger is in use but if we are here it
+ * means that the device IRQ is enabled:
+ * this is a single read EOC interrupt, we only need to call complete()
+ * and return.
+ */
+ if (!iio_buffer_enabled(indio_dev)) {
+ complete(&st->complete);
+ return IRQ_HANDLED;
+ }
+
ret = max1027_read_scan(indio_dev);
if (ret)
dev_err(&indio_dev->dev,
@@ -501,6 +525,7 @@ static int max1027_probe(struct spi_device *spi)
st->info = &max1027_chip_info_tbl[spi_get_device_id(spi)->driver_data];
mutex_init(&st->lock);
+ init_completion(&st->complete);
indio_dev->name = spi_get_device_id(spi)->name;
indio_dev->info = &max1027_info;
@@ -516,7 +541,7 @@ static int max1027_probe(struct spi_device *spi)
if (spi->irq) {
ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
&iio_pollfunc_store_time,
- &max1027_trigger_handler,
+ &max1027_threaded_handler,
NULL);
if (ret < 0) {
dev_err(&indio_dev->dev, "Failed to setup buffer\n");
--
2.27.0
> -----Original Message-----
> From: Miquel Raynal <[email protected]>
> Sent: Thursday, September 2, 2021 11:15 PM
> To: Jonathan Cameron <[email protected]>; Lars-Peter Clausen
> <[email protected]>; [email protected]; linux-
> [email protected]
> Cc: Thomas Petazzoni <[email protected]>; Sa, Nuno
> <[email protected]>; Miquel Raynal <[email protected]>
> Subject: [PATCH v2 14/16] iio: adc: max1027: Don't just sleep when the
> EOC interrupt is available
>
> [External]
>
> The interrupt will fire upon end of conversion. This currently can
> happen in two situations: either the cnvst trigger was enabled and
> toggled, or a single read was requested and the data is ready. The first
> situation is already covered while the second is not. Instead, a waiting
> delay is applied. Let's handle these interrupts more properly by adding
> second path in our EOC helper.
>
> Rename the interrupt handler to a more generic name as it won't only
> handle triggered situations.
>
> Signed-off-by: Miquel Raynal <[email protected]>
> ---
> drivers/iio/adc/max1027.c | 31 ++++++++++++++++++++++++++++---
> 1 file changed, 28 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/adc/max1027.c b/drivers/iio/adc/max1027.c
> index b85fe0a48ff9..e734d32a5507 100644
> --- a/drivers/iio/adc/max1027.c
> +++ b/drivers/iio/adc/max1027.c
> @@ -256,15 +256,27 @@ struct max1027_state {
> struct iio_trigger *trig;
> __be16 *buffer;
> struct mutex lock;
> + struct completion complete;
>
> u8 reg ____cacheline_aligned;
> };
>
> static int max1027_wait_eoc(struct iio_dev *indio_dev)
> {
> + struct max1027_state *st = iio_priv(indio_dev);
> unsigned int conversion_time =
> MAX1027_CONVERSION_UDELAY;
> + int ret;
>
> - usleep_range(conversion_time, conversion_time * 2);
> + if (st->spi->irq) {
> + ret = wait_for_completion_timeout(&st->complete,
> +
> msecs_to_jiffies(1000));
> + if (!ret)
> + return ret;
> +
> + reinit_completion(&st->complete);
I would call this before the waiting...
- Nuno Sá
Hi Nuno,
[email protected] wrote on Mon, 6 Sep 2021 09:38:02 +0000:
> > -----Original Message-----
> > From: Miquel Raynal <[email protected]>
> > Sent: Thursday, September 2, 2021 11:15 PM
> > To: Jonathan Cameron <[email protected]>; Lars-Peter Clausen
> > <[email protected]>; [email protected]; linux-
> > [email protected]
> > Cc: Thomas Petazzoni <[email protected]>; Sa, Nuno
> > <[email protected]>; Miquel Raynal <[email protected]>
> > Subject: [PATCH v2 14/16] iio: adc: max1027: Don't just sleep when the
> > EOC interrupt is available
> >
> > [External]
> >
> > The interrupt will fire upon end of conversion. This currently can
> > happen in two situations: either the cnvst trigger was enabled and
> > toggled, or a single read was requested and the data is ready. The first
> > situation is already covered while the second is not. Instead, a waiting
> > delay is applied. Let's handle these interrupts more properly by adding
> > second path in our EOC helper.
> >
> > Rename the interrupt handler to a more generic name as it won't only
> > handle triggered situations.
> >
> > Signed-off-by: Miquel Raynal <[email protected]>
> > ---
> > drivers/iio/adc/max1027.c | 31 ++++++++++++++++++++++++++++---
> > 1 file changed, 28 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/iio/adc/max1027.c b/drivers/iio/adc/max1027.c
> > index b85fe0a48ff9..e734d32a5507 100644
> > --- a/drivers/iio/adc/max1027.c
> > +++ b/drivers/iio/adc/max1027.c
> > @@ -256,15 +256,27 @@ struct max1027_state {
> > struct iio_trigger *trig;
> > __be16 *buffer;
> > struct mutex lock;
> > + struct completion complete;
> >
> > u8 reg ____cacheline_aligned;
> > };
> >
> > static int max1027_wait_eoc(struct iio_dev *indio_dev)
> > {
> > + struct max1027_state *st = iio_priv(indio_dev);
> > unsigned int conversion_time =
> > MAX1027_CONVERSION_UDELAY;
> > + int ret;
> >
> > - usleep_range(conversion_time, conversion_time * 2);
> > + if (st->spi->irq) {
> > + ret = wait_for_completion_timeout(&st->complete,
> > +
> > msecs_to_jiffies(1000));
> > + if (!ret)
> > + return ret;
> > +
> > + reinit_completion(&st->complete);
>
> I would call this before the waiting...
Sure, this is probably better.
Thanks,
Miquèl