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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New";color:black">* Seems like Ubuntu 14.04 does not export the GPIO hence there is no /sys/class/gpio<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New";color:black">The presence of /sys/class/gpio depends on the kernel configuration and not on the OS.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New";color:black">To enable this feature, you have to recompile the kernel after setting GPIO support and the “/sys/class/gpio/ (sysfs interface)”<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New";color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New";color:black"><a href="https://docs.blackfin.uclinux.org/doku.php?id=linux-kernel:drivers:gpio-sysfs">https://docs.blackfin.uclinux.org/doku.php?id=linux-kernel:drivers:gpio-sysfs</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New";color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">If you need only I2C, why are you trying to export a GPIO ?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">BTW I was in the same situation, I could detect nothing on the I2C lines. To fix this, I took the official kernel sources of the version 3.14.19 and I replaced the src of file i2c-designware-pcidrv.c (under <linux-3.14.19>/driver/i2c/busses)
by the last official version of this file. If you take a look in the source code, you will see some part of code relating baytrail.<o:p></o:p></p>
<p class="MsoNormal"><a href="https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/drivers/i2c/busses/i2c-designware-pcidrv.c">https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/drivers/i2c/busses/i2c-designware-pcidrv.c</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">After recompiling and installing the kernel, I was able to communicate with the device trough the I2C lines.<o:p></o:p></p>
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