Thanks, David. I am not competent enough on DT yet. I see one of the I2C devices has a pinctrl in the device-tree but i2c1 does not. I don't understand why/how when I open /dev/i2c-1 from userspace that the pins seem to get assigned. Hopefully Robert can help.
Mark On Tue, Jan 9, 2018 at 7:26 PM David Lechner <da...@lechnology.com> wrote: > Sounds like a question for RCN. I'm not up to speed on the pinctrl > situation on BeagleBone. I'm weird and don't use capemanager or any of the > usual BealgeBone stuff. > > But, I think you are right to think the problem is cause by pin muxing > somehow. > > > > On 01/09/2018 12:41 AM, Mark Grosen wrote: > > I moved 4.14.12-ti-r24 and now it gets past the the vbat regulator, but > then fails trying to write to the I2C with a bus ready timeout: > > mark@pocket:~/bb.org-overlays/src/arm$ dmesg | grep -P 'ssd|i2c' > [ 0.508117] omap_i2c 44e0b000.i2c: could not find pctldev for node > /ocp/l4_wkup@44c00000/scm@210000/pinmux@800/pinmux_i2c0_pins, deferring > probe > [ 0.509098] omap_i2c 4802a000.i2c: bus 1 rev0.11 at 400 kHz > [ 0.509821] omap_i2c 4819c000.i2c: bus 2 rev0.11 at 400 kHz > [ 1.945474] omap_i2c 4802a000.i2c: timeout waiting for bus ready > [ 1.945496] ssd1307fb 1-003c: Couldn't send I2C command 2. > [ 1.945554] ssd1307fb: probe of 1-003c failed with error -110 > [ 2.057076] i2c /dev entries driver > [ 2.178366] input: tps65217_pwr_but as > /devices/platform/ocp/44e0b000.i2c/i2c-0/0-0024/tps65217-pwrbutton/input/input0 > [ 2.179568] omap_i2c 44e0b000.i2c: bus 0 rev0.11 at 400 kHz > > After the boot finishes, I can use the device from userspace with no > problems. It seems that i2c-1 is registered before the ssd1307fb probe > happens. Are pins not assigned at this point? > > Mark > > On Mon, Jan 8, 2018 at 7:10 PM David Lechner <da...@lechnology.com> wrote: > >> The linux driver for this is an i2c driver. So the device tree node that >> you added will create an i2c device in the linux kernel (i.e. >> /sys/bus/i2c/devices/1-003c). Then udev sees that this device matches the >> compatible string of the "ssd1307fb" driver (you will see this listed in >> `lsmod`). This driver is bound to the device and calls the drivers probe >> function. This is where the error message is coming from. If the probe >> function had completed successfully, it would have registered a new fbdev >> device. >> >> It looks like this error is a bug in the linux kernel that was fixed in >> kernel v4.11. >> <https://github.com/torvalds/linux/commit/cfc5b2b551d8c089079e754525839101b1b43624> >> <https://github.com/torvalds/linux/commit/cfc5b2b551d8c089079e754525839101b1b43624> >> . >> >> You can work around this by adding a fixed regulator to the device tree >> and adding it to your device. Or, if you are compiling your own kernel >> anyway, you can grab the patch I linked. >> >> On 1/8/18 8:09 PM, Mark Grosen wrote: >> >> mark@pocket:~$ dmesg | grep -P 'fb|ssd' >> [ 2.165499] ssd1307fb 1-003c: failed to get VBAT regulator: -19 >> >> How does fbdev "find" the ssd1306? >> >> On Mon, Jan 8, 2018 at 5:51 PM David Lechner <da...@lechnology.com> >> wrote: >> >>> On 01/08/2018 07:27 PM, Mark Grosen wrote: >>> >>> On Mon, Jan 8, 2018 at 10:08 AM David Lechner <da...@lechnology.com> >>> wrote: >>> >>>> On 01/07/2018 05:59 PM, Mark Grosen wrote: >>>> > I am trying to get the kernel driver for the ssd1306 working with the >>>> PocketBeagle USB HUB cape which has a 64x32 SSD1306 display ( >>>> https://www.tindie.com/products/microwavemont/oled-with-24-port-usb-hub-cape-for-pocketbeagle/) >>>> I know it is physically working as I can use it via user-mode I2C. I >>>> believe a small change is needed to support the unusual 64 pixel width of >>>> this board. I have built and loaded a new kernel and have a .dtbo >>>> >>>> And what does your device tree overlay look like? >>>> >>> >>> /dts-v1/; >>> /plugin/; >>> >>> #include <dt-bindings/board/am335x-bbw-bbb-base.h> >>> #include <dt-bindings/gpio/gpio.h> >>> #include <dt-bindings/pinctrl/am33xx.h> >>> >>> / { >>> fragment@0 { >>> target = <&i2c1>; >>> __overlay__ { >>> status = "okay"; >>> >>> #address-cells = <1>; >>> #size-cells = <0>; >>> >>> ssd1306: oled@3c { >>> compatible = "solomon,ssd1306fb-i2c"; >>> reg = <0x3c>; >>> solomon,width = <64>; >>> solomon,height = <32>; >>> solomon,page-offset = <0>; >>> }; >>> }; >>> }; >>> }; >>> >>> >>>> >>>> > loaded via u-boot with 4.4.88-ti-r128 kernel. It shows up in >>>> /proc/device-tree correctly (at least as far as I can tell - the entries >>>> match the dts values). I am missing how to get this connected to the >>>> framebuffer world - there is no /dev/fb0 showing up. I see the config >>>> options appear to be enabled (I am using the defconfig). >>>> >>>> And which options did you enable/are enabled? >>> >>> >>> mark@pocket:~$ zcat /proc/config.gz | grep CONFIG_FB | grep -v '#' >>> CONFIG_FB=y >>> CONFIG_FB_CMDLINE=y >>> CONFIG_FB_NOTIFY=y >>> CONFIG_FB_CFB_FILLRECT=y >>> CONFIG_FB_CFB_COPYAREA=y >>> CONFIG_FB_CFB_IMAGEBLIT=y >>> CONFIG_FB_SYS_FILLRECT=y >>> CONFIG_FB_SYS_COPYAREA=y >>> CONFIG_FB_SYS_IMAGEBLIT=y >>> CONFIG_FB_SYS_FOPS=y >>> CONFIG_FB_DEFERRED_IO=y >>> CONFIG_FB_BACKLIGHT=y >>> CONFIG_FB_MODE_HELPERS=y >>> CONFIG_FB_TILEBLITTING=y >>> CONFIG_FB_SMSCUFX=m >>> CONFIG_FB_UDL=m >>> CONFIG_FB_SIMPLE=y >>> CONFIG_FB_SSD1307=y >>> >>> >>>> >>>> >>> Looks alright to me. Is there any error in `dmesg`? >>> >>> >>> -- >>> For more options, visit http://beagleboard.org/discuss >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "BeagleBoard" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to beagleboard+unsubscr...@googlegroups.com. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/beagleboard/8d1b9f53-ab73-6bf4-92d0-ebcfb072bb06%40lechnology.com >>> <https://groups.google.com/d/msgid/beagleboard/8d1b9f53-ab73-6bf4-92d0-ebcfb072bb06%40lechnology.com?utm_medium=email&utm_source=footer> >>> . >>> For more options, visit https://groups.google.com/d/optout. >>> >> -- >> For more options, visit http://beagleboard.org/discuss >> --- >> You received this message because you are subscribed to the Google Groups >> "BeagleBoard" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to beagleboard+unsubscr...@googlegroups.com. >> >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/beagleboard/CAL8ugEcSLFrFasGKqfX44iR-UDhzeNE9nt4u4Nfirj9oDnC20A%40mail.gmail.com >> <https://groups.google.com/d/msgid/beagleboard/CAL8ugEcSLFrFasGKqfX44iR-UDhzeNE9nt4u4Nfirj9oDnC20A%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> >> >> For more options, visit https://groups.google.com/d/optout. >> >> -- >> For more options, visit http://beagleboard.org/discuss >> --- >> You received this message because you are subscribed to the Google Groups >> "BeagleBoard" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to beagleboard+unsubscr...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/beagleboard/fab14b2e-8b97-b6ff-80e5-626edd04d9fa%40lechnology.com >> <https://groups.google.com/d/msgid/beagleboard/fab14b2e-8b97-b6ff-80e5-626edd04d9fa%40lechnology.com?utm_medium=email&utm_source=footer> >> . >> For more options, visit https://groups.google.com/d/optout. >> > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to beagleboard+unsubscr...@googlegroups.com. > > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/CAL8ugEdJZPRwWuYzZm5KbEmjGH%2B%2BfjYMmU%2B8aoPvzE_3HQ9OGQ%40mail.gmail.com > <https://groups.google.com/d/msgid/beagleboard/CAL8ugEdJZPRwWuYzZm5KbEmjGH%2B%2BfjYMmU%2B8aoPvzE_3HQ9OGQ%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > > > For more options, visit https://groups.google.com/d/optout. > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to beagleboard+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/ab8e70c0-1b4d-e3ec-d49c-26a75ff68a5d%40lechnology.com > <https://groups.google.com/d/msgid/beagleboard/ab8e70c0-1b4d-e3ec-d49c-26a75ff68a5d%40lechnology.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. 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