RE: BBB IIO ADC access not working

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> -----Original Message-----
> From: Michael Welling [mailto:mwelling79@xxxxxxxxx] On Behalf 
> Of Michael Welling
> Sent: Thursday, August 20, 2015 9:14 AM
> To: Greg Wilson-Lindberg
> Cc: Daniel Baluta; linux-iio@xxxxxxxxxxxxxxx
> Subject: Re: BBB IIO ADC access not working
> 
> On Thu, Aug 20, 2015 at 08:50:28AM -0700, Greg Wilson-Lindberg wrote:
> >  
> > 
> > > -----Original Message-----
> > > From: Michael Welling [mailto:mwelling79@xxxxxxxxx] On Behalf Of 
> > > Michael Welling
> > > Sent: Wednesday, August 19, 2015 2:43 PM
> > > To: Greg Wilson-Lindberg
> > > Cc: Daniel Baluta; linux-iio@xxxxxxxxxxxxxxx
> > > Subject: Re: BBB IIO ADC access not working
> > > 
> > > On Wed, Aug 19, 2015 at 02:34:39PM -0700, Greg 
> Wilson-Lindberg wrote:
> > > > 
> > > > So, in that case, can I just open it once and leave it open?
> > > 
> > > Yes.
> > > 
> > > > Is it reading from a buffer, or is it reading what is
> > > current in the ADC? 
> > > 
> > > It is the current reading.
> > > 
> > > > Can I just set up a timer to get readings to average then?
> > > 
> > > Sure.
> > > 
> > > Here are some helper functions:
> > > 
> > > int iio_adc_open_channel(int dev_num, int chan_num) {
> > > 	char filename[255];
> > > 
> > > 	sprintf(filename,
> > > "/sys/bus/iio/devices/iio:device%d/in_voltage%d_raw",
> > > 			dev_num, chan_num);
> > > 
> > > 	return open(filename, O_RDONLY);
> > > }
> > > 
> > > int iio_adc_read_channel(int fd)
> > > {
> > > 	int count;
> > > 	char buffer[255];
> > > 	int value = -1;
> > > 
> > > 	lseek(fd,0,SEEK_SET);
> > > 
> > > 	count = read(fd, buffer, 255);
> > > 
> > > 	if (count > 0)
> > > 		value = strtoul(buffer, NULL, 10);
> > > 
> > > 	return value;
> > > }
> > > 
> > > Example usage:
> > > 
> > > int fd;
> > > .
> > > .
> > > 
> > > fd = iio_adc_open_channel(0, 4);
> > > .
> > > .
> > > 
> > > while (1)
> > > {
> > > 	printf("ADC = %x\n", iio_adc_read_channel(fd)); }
> > > 
> > > 
> > 
> > I converted to using this interface and left the system running 
> > overnight and the touch screen was locked up this morning.
> 
> This is without any modifications to the kernel?
> 

This was still running the kernel modifications.  I've restarted it this morning 
without the kernel modifications.--
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