Hi Javier, What about NOT TOP-POSTING, as I requested once already? On Wed, 9 Dec 2009 16:29:34 +0100, Javier Zugasti wrote: > Thank you very much for your reply Jean. > I patched the kernel tree with the patch you linked me to and then selected > the hwmon and lm73 option in the menuconfig options (together with the i2c > of course). > > After that I used a cross-compiler to compile the kernel for my board and > transferred the images to my board and started my linux there. > > I assume the system supports i2c now. > No i2c devices appear in the /dev directory or in /sys/bus/i2c/devices Which kernel are you running? I2C adapters only show in /sys/bus/i2c/devices since kernel 2.6.32. For older kernels you would look for them in /sys/class/i2c-adapter. Assuming you run an older kernel, please list the entries under /sys/class/i2c-adapter. , but > the lm73 appears in /sys/bus/i2c/drivers and i2c appears in the file > /proc/devices: > > cat /proc/devices > Character devices: > ... > *89 i2c* > ... This means i2c-dev is loaded, but you shouldn't need it, see below. > So now, how can I write an application in the user space that reads the > temperature from the lm73? Do I have to use IOCTL calls or how do I do it? With the lm73 driver you're using, access to the LM73 chip is done through sysfs, very easily. You would have to go through ioctls on /dev/i2c* nodes only if you did _not_ have a kernel driver for the LM73. -- Jean Delvare http://khali.linux-fr.org/wishlist.html _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
