On Wed, Oct 24, 2018 at 4:08 PM Mark A. Yoder <[email protected]> wrote: > > I'd like to change the i2c bus 2 to 400kHz. > > I see it's currently running at 100kHz. > > bone$ dmesg | grep i2c > [ 0.622594] omap_i2c 44e0b000.i2c: could not find pctldev for node > /ocp/l4_wkup@44c00000/scm@210000/pinmux@800/pinmux_i2c0_pins, deferring probe > [ 0.623608] omap_i2c 4802a000.i2c: bus 1 rev0.11 at 100 kHz > [ 0.625035] omap_i2c 4819c000.i2c: bus 2 rev0.11 at 100 kHz > [ 1.357694] i2c /dev entries driver > [ 1.543350] input: tps65217_pwr_but as > /devices/platform/ocp/44e0b000.i2c/i2c-0/0-0024/tps65217-pwrbutton/input/input0 > [ 1.544568] omap_i2c 44e0b000.i2c: bus 0 rev0.11 at 400 kHz > > The speed appears to be set here: > > bone$ uname -a > Linux beaglebone 4.14.52-ti-rt-r60 #1 SMP PREEMPT Tue Jun 26 23:28:55 UTC > 2018 armv7l GNU/Linux > bone$ cd /opt/source/dtb-4.14-ti/src/arm/ > > Looking in am335x-bone-common.dtsi I see: > &i2c2 { > pinctrl-names = "default"; > //pinctrl-0 = <&i2c2_pins>; > pinctrl-0 = <>; > > status = "okay"; > clock-frequency = <100000>; > > I assume I can change the clock-frequency to 400000. > But what do I do next? I don't see am335x-bone-common.dtsi in > /boot//boot/dtbs/4.14.52-ti-r60. > > Or, is there way way to change the clock after booting?
Correct, after bootup, you can't currently change that.. Some users have been using the i2c-fast overlay from the bb.org-overlay repo.. https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/BB-I2C2-FAST-00A0.dts Regards, -- Robert Nelson https://rcn-ee.com/ -- 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/CAOCHtYjCxwuS2R%2BVip-vcbyOZtrSBhORvRy3QzR5CqE0KHbftQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
