Issue using eQEP module

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Paulo Sherring

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May 12, 2016, 10:17:41 PM5/12/16
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Hi all! I am trying to use the eQEP device driver, found here:

So, I could get the module loaded by echoing the device tree to cape manager. After disabling eMMC and HDMI, all 0-2 modules loaded OK.
I hooked up my encoder, which uses open NPN to the board, powering it up from the 5V onboard.
Since the output is open collector NPN, i needed to use pullup. So, i edited the dts file as follows:
(For eQEP1)
0x0D8 0x32  /* P8_31 = GPIO0_10 = EQEP1_index, MODE2 */
0x0DC 0x32  /* P8_32 = GPIO0_11 = EQEP1_strobe, MODE2 */
0x0D4 0x32  /* P8_33 = GPIO0_9 = EQEP1B_in, MODE2 */
0x0D0 0x32  /* P8_35 = GPIO0_8 = EQEP1A_in, MODE2 */

After compiling, installing and echoing it again to capemgr, the entry in sysfs is created as expected, but, when i read pinmux config, I read back 0X2A. After overwriting it with devmem, I also get again 0X2A. Can anyone give me any direction?

My setup:
BeagleBone Black Element14
KernVer: 4.4.0-bone-rt-r3.1
uEnv:
dtb=am335x-boneblack-overlay.dtb


Thanks in advance!
Paulo Sherring.

evilwulfie

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May 12, 2016, 10:50:29 PM5/12/16
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I do this for them pins in my dts file makes it easier to read

                    BONE_P8_31 (PIN_INPUT | MUX_MODE6)           /* (V4) lcd_data14.uart5_ctsn */
                    BONE_P8_32 (PIN_OUTPUT | MUX_MODE6)          /* (T5) lcd_data15.uart5_rtsn */
                    BONE_P8_33 (PIN_OUTPUT | MUX_MODE6)          /* uart4_rtsn */
not using p8-35
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Paulo Sherring

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May 13, 2016, 12:48:36 AM5/13/16
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So, turns out that the DTBO being compiled was, for some unknown reason, wrong. I copied the files from /beaglebot/tree/master/encoders/dts into /beagleboard/bb.org-overlays/src/arm/ and ran make clean | make |  make install. This generated a file with the -00A0 sufix and another without. The one without the sufix was somehow messed up and was being loaded instead. I am terrible with these overlays and device trees thingy :/

Thanks anyway. And I hope this can, somehow, help someone.
Paulo Sherring.
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