2021-06-14 14:20:29

by Chris Lesiak

Subject: [PATCH v3] iio: humidity: hdc100x: Add margin to the conversion time

The datasheets have the following note for the conversion time
specification: "This parameter is specified by design and/or
characterization and it is not tested in production."

Parts have been seen that require more time to do 14-bit conversions for
the relative humidity channel. The result is ENXIO due to the address
phase of a transfer not getting an ACK.

Delay an additional 1 ms per conversion to allow for additional margin.

Fixes: 4839367d99e3 ("iio: humidity: add HDC100x support")
Signed-off-by: Chris Lesiak <[email protected]>
---
drivers/iio/humidity/hdc100x.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/humidity/hdc100x.c b/drivers/iio/humidity/hdc100x.c
index 2a957f19048e..9e0fce917ce4 100644
--- a/drivers/iio/humidity/hdc100x.c
+++ b/drivers/iio/humidity/hdc100x.c
@@ -25,6 +25,8 @@
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>

+#include <linux/time.h>
+
#define HDC100X_REG_TEMP 0x00
#define HDC100X_REG_HUMIDITY 0x01

@@ -166,7 +168,7 @@ static int hdc100x_get_measurement(struct hdc100x_data *data,
struct iio_chan_spec const *chan)
{
struct i2c_client *client = data->client;
- int delay = data->adc_int_us[chan->address];
+ int delay = data->adc_int_us[chan->address] + 1*USEC_PER_MSEC;
int ret;
__be16 val;

@@ -316,7 +318,7 @@ static irqreturn_t hdc100x_trigger_handler(int irq, void *p)
struct iio_dev *indio_dev = pf->indio_dev;
struct hdc100x_data *data = iio_priv(indio_dev);
struct i2c_client *client = data->client;
- int delay = data->adc_int_us[0] + data->adc_int_us[1];
+ int delay = data->adc_int_us[0] + data->adc_int_us[1] + 2*USEC_PER_MSEC;
int ret;

/* dual read starts at temp register */
--
2.26.2

2021-06-16 18:23:23

by Jonathan Cameron

Subject: Re: [PATCH v3] iio: humidity: hdc100x: Add margin to the conversion time

On Mon, 14 Jun 2021 09:18:20 -0500
Chris Lesiak <[email protected]> wrote:

> The datasheets have the following note for the conversion time
> specification: "This parameter is specified by design and/or
> characterization and it is not tested in production."
>
> Parts have been seen that require more time to do 14-bit conversions for
> the relative humidity channel. The result is ENXIO due to the address
> phase of a transfer not getting an ACK.
>
> Delay an additional 1 ms per conversion to allow for additional margin.
>
> Fixes: 4839367d99e3 ("iio: humidity: add HDC100x support")
> Signed-off-by: Chris Lesiak <[email protected]>

+CC Matt as this is one of his drivers.

Looks good to me.

> ---
> drivers/iio/humidity/hdc100x.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iio/humidity/hdc100x.c b/drivers/iio/humidity/hdc100x.c
> index 2a957f19048e..9e0fce917ce4 100644
> --- a/drivers/iio/humidity/hdc100x.c
> +++ b/drivers/iio/humidity/hdc100x.c
> @@ -25,6 +25,8 @@
> #include <linux/iio/trigger_consumer.h>
> #include <linux/iio/triggered_buffer.h>
>
> +#include <linux/time.h>
> +
> #define HDC100X_REG_TEMP 0x00
> #define HDC100X_REG_HUMIDITY 0x01
>
> @@ -166,7 +168,7 @@ static int hdc100x_get_measurement(struct hdc100x_data *data,
> struct iio_chan_spec const *chan)
> {
> struct i2c_client *client = data->client;
> - int delay = data->adc_int_us[chan->address];
> + int delay = data->adc_int_us[chan->address] + 1*USEC_PER_MSEC;
> int ret;
> __be16 val;
>
> @@ -316,7 +318,7 @@ static irqreturn_t hdc100x_trigger_handler(int irq, void *p)
> struct iio_dev *indio_dev = pf->indio_dev;
> struct hdc100x_data *data = iio_priv(indio_dev);
> struct i2c_client *client = data->client;
> - int delay = data->adc_int_us[0] + data->adc_int_us[1];
> + int delay = data->adc_int_us[0] + data->adc_int_us[1] + 2*USEC_PER_MSEC;
> int ret;
>
> /* dual read starts at temp register */

2021-07-18 14:50:43

by Jonathan Cameron

Subject: Re: [PATCH v3] iio: humidity: hdc100x: Add margin to the conversion time

On Wed, 16 Jun 2021 13:43:35 +0100
Jonathan Cameron <[email protected]> wrote:

> On Mon, 14 Jun 2021 09:18:20 -0500
> Chris Lesiak <[email protected]> wrote:
>
> > The datasheets have the following note for the conversion time
> > specification: "This parameter is specified by design and/or
> > characterization and it is not tested in production."
> >
> > Parts have been seen that require more time to do 14-bit conversions for
> > the relative humidity channel. The result is ENXIO due to the address
> > phase of a transfer not getting an ACK.
> >
> > Delay an additional 1 ms per conversion to allow for additional margin.
> >
> > Fixes: 4839367d99e3 ("iio: humidity: add HDC100x support")
> > Signed-off-by: Chris Lesiak <[email protected]>
>
> +CC Matt as this is one of his drivers.

@Matt. Ping.

>
> Looks good to me.
>
> > ---
> > drivers/iio/humidity/hdc100x.c | 6 ++++--
> > 1 file changed, 4 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/iio/humidity/hdc100x.c b/drivers/iio/humidity/hdc100x.c
> > index 2a957f19048e..9e0fce917ce4 100644
> > --- a/drivers/iio/humidity/hdc100x.c
> > +++ b/drivers/iio/humidity/hdc100x.c
> > @@ -25,6 +25,8 @@
> > #include <linux/iio/trigger_consumer.h>
> > #include <linux/iio/triggered_buffer.h>
> >
> > +#include <linux/time.h>
> > +
> > #define HDC100X_REG_TEMP 0x00
> > #define HDC100X_REG_HUMIDITY 0x01
> >
> > @@ -166,7 +168,7 @@ static int hdc100x_get_measurement(struct hdc100x_data *data,
> > struct iio_chan_spec const *chan)
> > {
> > struct i2c_client *client = data->client;
> > - int delay = data->adc_int_us[chan->address];
> > + int delay = data->adc_int_us[chan->address] + 1*USEC_PER_MSEC;
> > int ret;
> > __be16 val;
> >
> > @@ -316,7 +318,7 @@ static irqreturn_t hdc100x_trigger_handler(int irq, void *p)
> > struct iio_dev *indio_dev = pf->indio_dev;
> > struct hdc100x_data *data = iio_priv(indio_dev);
> > struct i2c_client *client = data->client;
> > - int delay = data->adc_int_us[0] + data->adc_int_us[1];
> > + int delay = data->adc_int_us[0] + data->adc_int_us[1] + 2*USEC_PER_MSEC;
> > int ret;
> >
> > /* dual read starts at temp register */
>

2021-07-18 21:32:58

by Matt Ranostay

Subject: Re: [PATCH v3] iio: humidity: hdc100x: Add margin to the conversion time

On Sun, Jul 18, 2021 at 7:49 AM Jonathan Cameron <[email protected]> wrote:
>
> On Wed, 16 Jun 2021 13:43:35 +0100
> Jonathan Cameron <[email protected]> wrote:
>
> > On Mon, 14 Jun 2021 09:18:20 -0500
> > Chris Lesiak <[email protected]> wrote:
> >
> > > The datasheets have the following note for the conversion time
> > > specification: "This parameter is specified by design and/or
> > > characterization and it is not tested in production."
> > >
> > > Parts have been seen that require more time to do 14-bit conversions for
> > > the relative humidity channel. The result is ENXIO due to the address
> > > phase of a transfer not getting an ACK.
> > >
> > > Delay an additional 1 ms per conversion to allow for additional margin.
> > >
> > > Fixes: 4839367d99e3 ("iio: humidity: add HDC100x support")
> > > Signed-off-by: Chris Lesiak <[email protected]>
> >
> > +CC Matt as this is one of his drivers.
>
> @Matt. Ping.
>
> >
> > Looks good to me.

Looks good to me as well.

Acked-by: Matt Ranostay <[email protected]>

> >
> > > ---
> > > drivers/iio/humidity/hdc100x.c | 6 ++++--
> > > 1 file changed, 4 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/iio/humidity/hdc100x.c b/drivers/iio/humidity/hdc100x.c
> > > index 2a957f19048e..9e0fce917ce4 100644
> > > --- a/drivers/iio/humidity/hdc100x.c
> > > +++ b/drivers/iio/humidity/hdc100x.c
> > > @@ -25,6 +25,8 @@
> > > #include <linux/iio/trigger_consumer.h>
> > > #include <linux/iio/triggered_buffer.h>
> > >
> > > +#include <linux/time.h>
> > > +
> > > #define HDC100X_REG_TEMP 0x00
> > > #define HDC100X_REG_HUMIDITY 0x01
> > >
> > > @@ -166,7 +168,7 @@ static int hdc100x_get_measurement(struct hdc100x_data *data,
> > > struct iio_chan_spec const *chan)
> > > {
> > > struct i2c_client *client = data->client;
> > > - int delay = data->adc_int_us[chan->address];
> > > + int delay = data->adc_int_us[chan->address] + 1*USEC_PER_MSEC;
> > > int ret;
> > > __be16 val;
> > >
> > > @@ -316,7 +318,7 @@ static irqreturn_t hdc100x_trigger_handler(int irq, void *p)
> > > struct iio_dev *indio_dev = pf->indio_dev;
> > > struct hdc100x_data *data = iio_priv(indio_dev);
> > > struct i2c_client *client = data->client;
> > > - int delay = data->adc_int_us[0] + data->adc_int_us[1];
> > > + int delay = data->adc_int_us[0] + data->adc_int_us[1] + 2*USEC_PER_MSEC;
> > > int ret;
> > >
> > > /* dual read starts at temp register */
> >
>

2021-07-24 17:13:28

by Jonathan Cameron

Subject: Re: [PATCH v3] iio: humidity: hdc100x: Add margin to the conversion time

On Sun, 18 Jul 2021 14:31:28 -0700
Matt Ranostay <[email protected]> wrote:

> On Sun, Jul 18, 2021 at 7:49 AM Jonathan Cameron <[email protected]> wrote:
> >
> > On Wed, 16 Jun 2021 13:43:35 +0100
> > Jonathan Cameron <[email protected]> wrote:
> >
> > > On Mon, 14 Jun 2021 09:18:20 -0500
> > > Chris Lesiak <[email protected]> wrote:
> > >
> > > > The datasheets have the following note for the conversion time
> > > > specification: "This parameter is specified by design and/or
> > > > characterization and it is not tested in production."
> > > >
> > > > Parts have been seen that require more time to do 14-bit conversions for
> > > > the relative humidity channel. The result is ENXIO due to the address
> > > > phase of a transfer not getting an ACK.
> > > >
> > > > Delay an additional 1 ms per conversion to allow for additional margin.
> > > >
> > > > Fixes: 4839367d99e3 ("iio: humidity: add HDC100x support")
> > > > Signed-off-by: Chris Lesiak <[email protected]>
> > >
> > > +CC Matt as this is one of his drivers.
> >
> > @Matt. Ping.
> >
> > >
> > > Looks good to me.
>
> Looks good to me as well.
>
> Acked-by: Matt Ranostay <[email protected]>

Thanks.

Applied to the fixes-togreg branch of iio.git and marked for stable.

Jonathan

>
> > >
> > > > ---
> > > > drivers/iio/humidity/hdc100x.c | 6 ++++--
> > > > 1 file changed, 4 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/drivers/iio/humidity/hdc100x.c b/drivers/iio/humidity/hdc100x.c
> > > > index 2a957f19048e..9e0fce917ce4 100644
> > > > --- a/drivers/iio/humidity/hdc100x.c
> > > > +++ b/drivers/iio/humidity/hdc100x.c
> > > > @@ -25,6 +25,8 @@
> > > > #include <linux/iio/trigger_consumer.h>
> > > > #include <linux/iio/triggered_buffer.h>
> > > >
> > > > +#include <linux/time.h>
> > > > +
> > > > #define HDC100X_REG_TEMP 0x00
> > > > #define HDC100X_REG_HUMIDITY 0x01
> > > >
> > > > @@ -166,7 +168,7 @@ static int hdc100x_get_measurement(struct hdc100x_data *data,
> > > > struct iio_chan_spec const *chan)
> > > > {
> > > > struct i2c_client *client = data->client;
> > > > - int delay = data->adc_int_us[chan->address];
> > > > + int delay = data->adc_int_us[chan->address] + 1*USEC_PER_MSEC;
> > > > int ret;
> > > > __be16 val;
> > > >
> > > > @@ -316,7 +318,7 @@ static irqreturn_t hdc100x_trigger_handler(int irq, void *p)
> > > > struct iio_dev *indio_dev = pf->indio_dev;
> > > > struct hdc100x_data *data = iio_priv(indio_dev);
> > > > struct i2c_client *client = data->client;
> > > > - int delay = data->adc_int_us[0] + data->adc_int_us[1];
> > > > + int delay = data->adc_int_us[0] + data->adc_int_us[1] + 2*USEC_PER_MSEC;
> > > > int ret;
> > > >
> > > > /* dual read starts at temp register */
> > >
> >