Sure, you can do that. Nice to see that you are using Diolan DLN-2 adapter. thanks, Daniel. On Mon, Apr 2, 2018 at 8:06 PM, Gaston Gonzalez <gascoar@xxxxxxxxx> wrote: > Hi, > > I'm testing an AD7746 eval board using a Diolan DLN-2 adapter. I wrote > some basic notes about the installation an instanciation process for my > own use. But then I thought it could be useful for someone else. So > maybe I could put this in the kernel newbies page under the IIO section? > > If you think is worth it, I would be glad to add it to the wiki page. > > Best regards, > > Gaston > > Notes: > > The setup > ========= > > AD7746-EVAL BOARD --> Diolan DLN-2 Adapter --> Thinkpad T430 > > The connection between the AD7746 eval board and adapter is as detailed > in [2] I2C Interface Configuration Options, External connection (pag 4). > > The connection between Diolan DLN-2 and the T430 is USB straighforward. > > Drivers > ======= > > Both in mainline kernel: > > - Diolan DLN-2 driver: I2C_DLN2 (prompt Diolan DLN-2 USB I2C adapter) > Loc: drivers/i2c/busses/ > - AD7746: AD7746 > Loc: drivers/staging/iio/cdc/ > > Bus of interest > =============== > > $ sudo i2cdetect -l > > We get something like: > > ... > i2c-10 i2c dln2-i2c-1-1.2:1.0-0 I2C adapter > ... > > So our bus is the number 10. > > Getting the address > =================== > > $ sudo i2cdetect -y -r 10 > > We get something like: > > 0 1 2 3 4 5 6 7 8 9 a b c d e f > 00: -- -- -- -- -- -- -- -- -- -- -- -- -- > 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 40: -- -- -- -- -- -- -- -- 48 -- -- -- -- -- -- -- > 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 70: -- -- -- -- -- -- -- -- > > 3. Device instantiation: > > # echo add7746 0x48 > /sys/bus/i2c/devices/i2c-10/new_device > > We must see something like: > > $ cd /sys/bus/i2c/devices/i2c-10/10-0048/ > $ ls > driver iio:device0 modalias name power subsystem uevent > > $ cd iio:device0 > $ ls > dev in_capacitance-capacitance_calibbias > in_capacitance0_calibbias_calibration in_capacitance-capacitance_sampling_frequency > in_capacitance0_calibscale in_capacitance-capacitance_scale > in_capacitance0_calibscale_calibration in_capacitance_sampling_frequency > in_capacitance0-capacitance2_calibscale in_capacitance_sampling_frequency_available > in_capacitance0-capacitance2_offset in_capacitance_scale > in_capacitance0-capacitance2_raw in_temp0_input > in_capacitance0_offset in_temp1_input > in_capacitance0_raw in_voltage0_calibscale_calibration > in_capacitance1_calibbias_calibration in_voltage0_raw > in_capacitance1_calibscale in_voltage1_supply_raw > in_capacitance1_calibscale_calibration in_voltage_sampling_frequency > in_capacitance1-capacitance3_calibscale in_voltage_sampling_frequency_available > in_capacitance1-capacitance3_offset in_voltage_scale > in_capacitance1-capacitance3_raw name > in_capacitance1_offset power > in_capacitance1_raw subsystem > in_capacitance_calibbias uevent > > Checking the permits: > > $ ll > -r--r--r-- 1 root root 4096 mar 31 09:57 dev > --w------- 1 root root 4096 mar 31 09:57 in_capacitance0_calibbias_calibration > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance0_calibscale > --w------- 1 root root 4096 mar 31 09:57 in_capacitance0_calibscale_calibration > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance0-capacitance2_calibscale > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance0-capacitance2_offset > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance0-capacitance2_raw > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance0_offset > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance0_raw > --w------- 1 root root 4096 mar 31 09:57 in_capacitance1_calibbias_calibration > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance1_calibscale > --w------- 1 root root 4096 mar 31 09:57 in_capacitance1_calibscale_calibration > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance1-capacitance3_calibscale > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance1-capacitance3_offset > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance1-capacitance3_raw > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance1_offset > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance1_raw > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance_calibbias > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance-capacitance_calibbias > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance-capacitance_sampling_frequency > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance-capacitance_scale > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance_sampling_frequency > -r--r--r-- 1 root root 4096 mar 31 09:57 in_capacitance_sampling_frequency_available > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_capacitance_scale > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_temp0_input > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_temp1_input > --w------- 1 root root 4096 mar 31 09:57 in_voltage0_calibscale_calibration > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_voltage0_raw > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_voltage1_supply_raw > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_voltage_sampling_frequency > -r--r--r-- 1 root root 4096 mar 31 09:57 in_voltage_sampling_frequency_available > -rw-r--r-- 1 root root 4096 mar 31 09:57 in_voltage_scale > -r--r--r-- 1 root root 4096 mar 31 09:57 name > drwxr-xr-x 2 root root 0 mar 31 09:57 power > lrwxrwxrwx 1 root root 0 mar 31 09:57 subsystem -> ../../../../../../../../../../../bus/iio > -rw-r--r-- 1 root root 4096 mar 31 09:57 uevent > > 4. Capacitance > > According to [2], the capacitive length sensor is connected to CIN2+ and > CIN2-. In the driver, the values are mapped to capacitance0. > > Raw values vs sensor length: > > Note: (+) values means the sensor was moved to the left, (-) values > means the sensor was moved to the right. I.e. +1 cm means the rule was > moved 1 to the left, while -1 means the rule was moved 1 cm to the > right. > > Note2: note the raw value for -10 is 8224733, while +10 is -8224726, the > difference is because when the rule is moved 10 cm to the left, the is > still 2 o 3 cm of dielectric between the plates. The design is obviously > thought to move the rule to the right. > > > Length (cm) | Raw Value Cap0 > ------------------------------ > -10 -8224733 > -9 -8224730 > -8 -8224728 > -7 -8224725 > -6 -8224724 > -5 -8224722 > -4 -8224720 > -3 -8224718 > -2 -8224716 > -1 -8224714 > +0 -8224711 > +1 -8224711 > +2 -8224711 > +3 -8224711 > +4 -8224713 > +5 -8224715 > +6 -8224717 > +7 -8224719 > +8 -8224721 > +9 -8224723 > +10 -8224726 > > > References > ========== > > [1] http://www.analog.com/media/en/technical-documentation/data-sheets/AD7745_7746.pdf > [2] http://www.analog.com/media/en/technical-documentation/evaluation-documentation/EVAL-AD7746EB.PDF > [3] https://i2c.wiki.kernel.org/index.php/Main_Page > [4] https://kernelsense.wordpress.com/2016/01/22/achievement-unlocked-first-iio-driver/ > > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies@xxxxxxxxxxxxxxxxx > https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
