Trying to dump the pinmux states (/sys/kernel/debug/pinctrl/48002030.pinmux/pins) in 3.11 seems to cause a kernel crash:
http://paste.ubuntu.com/6302171/
GPIO access via /sys/class/gpio appears to be nonoperational in 3.11. It looks like a reasonable assumption that GPIOs may not be muxed into the GPIO pins.
I tried to add a devicetree entry to to force-mux GPIOs:
&omap3_pmx_core {
vvv_gpio_pins: pinmux_gpio_pins {
pinctrl-single,pins = <
0x134 (PIN_OUTPUT | MUX_MODE4) /* gpio_137 /
0x135 (PIN_OUTPUT | MUX_MODE4) / gpio_138 /
0x136 (PIN_OUTPUT | MUX_MODE4) / gpio_139 */
;
};
};
&ocp {
gpio_helper: helper {
compatible = “ti,omap3-gpio”;
pinctrl-names = “default”;
pinctrl-0 = <&vvv_gpio_pins>;
status = “okay”;
};
};
Doesn’t seem to do anything. The only indication that the kernel is actually trying to parse the fake “helper” device is these lines in the message log:
[ 0.369201] omap_gpio helper.26: could not find pctldev for node /ocp/pinmux@48002030/pinmux_gpio_pins, deferring probe
[ 0.369232] platform helper.26: Driver omap_gpio requests probe deferral
<...>
[ 3.354125] omap_gpio helper.26: Invalid IRQ resource
Obviously, I have no idea what “compatible” driver should I chose, omap3_gpio just sounded like something that could fit. For BBB they reference bone-pinmux-helper, which I assume is BBB-specific?
Thanks!