2013-08-28 23:08:46

by Jerome Oufella

[permalink] [raw]
Subject: Re: sht15 kernel driver

Chris Rodley <[email protected]> writes:

> Hi,
>
> I am trying to get a sht75 humidity and temperature sensor working
> with the linux kernel module in 3.2.
> Is there a code example for application code that you have available?
>
> Many thanks,

Hi Chris,

There was much less support for the sht15 back in 3.2 compared to recent
kernel releases. You may want to backport features and/or fixes to suit
your needs.

You can find a usage example for 3.2 in arch/arm/mach-pxa/stargate2.c
around line 140:

First, create a platform data struct and specify which GPIO lines are
hooked to the data and sck lines of your sht-15:

static struct sht15_platform_data platform_data_sht15 = {
.gpio_data = 100,
.gpio_sck = 98,
};

Then setup a platform device referencing those platform data, that you
will have to register on the platform bus using platform_add_devices()
or equivalent:

static struct platform_device sht15 = {
.name = "sht15",
.id = -1,
.dev = {
.platform_data = &platform_data_sht15,
},
};

...

platform_add_devices(...);



Cheers,
--
Jérôme Oufella
@: [email protected]
T: 514-276-5468 ext. 125


2013-08-29 03:43:36

by Chris Rodley

[permalink] [raw]
Subject: Re: sht15 kernel driver

Thanks Jerome!

That was just what I needed to know.
The device is now set up and is working well - I will have a go at back
porting now.

Many thanks again for your help!
Chris

On 29/08/13 11:08, Jerome Oufella wrote:
>> Hi,
>>
>> I am trying to get a sht75 humidity and temperature sensor working
>> with the linux kernel module in 3.2.
>> Is there a code example for application code that you have available?
>>
>> Many thanks,
> Hi Chris,
>
> There was much less support for the sht15 back in 3.2 compared to recent
> kernel releases. You may want to backport features and/or fixes to suit
> your needs.
>
> You can find a usage example for 3.2 in arch/arm/mach-pxa/stargate2.c
> around line 140:
>
> First, create a platform data struct and specify which GPIO lines are
> hooked to the data and sck lines of your sht-15:
>
> static struct sht15_platform_data platform_data_sht15 = {
> .gpio_data = 100,
> .gpio_sck = 98,
> };
>
> Then setup a platform device referencing those platform data, that you
> will have to register on the platform bus using platform_add_devices()
> or equivalent:
>
> static struct platform_device sht15 = {
> .name = "sht15",
> .id = -1,
> .dev = {
> .platform_data = &platform_data_sht15,
> },
> };
>
> ...
>
> platform_add_devices(...);
>
>
>
> Cheers,

2013-08-29 15:02:20

by Jerome Oufella

[permalink] [raw]
Subject: Re: sht15 kernel driver

Chris Rodley <[email protected]> writes:

> Thanks Jerome!
>
> That was just what I needed to know.
> The device is now set up and is working well - I will have a go at
> back porting now.
>
> Many thanks again for your help!
> Chris

Good to know Chris!

Note, we noticed that the sht15 driver may be sensible to noisy lines,
we suspect a race condition around the interrupt handling code.

If your sensor is populated on the board you shouldn't have problems
though.

Jerome

2013-08-29 15:28:38

by Guenter Roeck

[permalink] [raw]
Subject: Re: [lm-sensors] sht15 kernel driver

On Thu, Aug 29, 2013 at 11:02:16AM -0400, Jerome Oufella wrote:
> Chris Rodley <[email protected]> writes:
>
> > Thanks Jerome!
> >
> > That was just what I needed to know.
> > The device is now set up and is working well - I will have a go at
> > back porting now.
> >
> > Many thanks again for your help!
> > Chris
>
> Good to know Chris!
>
> Note, we noticed that the sht15 driver may be sensible to noisy lines,
> we suspect a race condition around the interrupt handling code.
>
Any proposed fixes ?

Guenter

> If your sensor is populated on the board you shouldn't have problems
> though.
>
> Jerome
>
> _______________________________________________
> lm-sensors mailing list
> [email protected]
> http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
>

2013-08-29 21:58:17

by Chris Rodley

[permalink] [raw]
Subject: Re: sht15 kernel driver

On 30/08/13 03:02, Jerome Oufella wrote:
> Chris Rodley <[email protected]> writes:
>> Thanks Jerome!
>>
>> That was just what I needed to know.
>> The device is now set up and is working well - I will have a go at
>> back porting now.
>>
>> Many thanks again for your help!
>> Chris
> Good to know Chris!
>
> Note, we noticed that the sht15 driver may be sensible to noisy lines,
> we suspect a race condition around the interrupt handling code.
>
> If your sensor is populated on the board you shouldn't have problems
> though.
>
> Jerome

Hi,

We have it working really well .. not noticing any issues - so far at least.
It is being populated more or less directly on the board - just via a
daughter board in the prototype phase.
So I might not see the same issues.

If we find anything I will submit it back to you.

Many thanks again for your advice!
Chris