Hi, I'm having some issues with the i2c-mxs driver in 3.9. Marek already pointed me to the patches from Lucas and that greatly improved the situation. For the context, my board has three nau7802 adcs, connected to a gpio i2c-muxer, connected to i2c1. Here is what I observe: On 3.9: # time cat /sys/bus/iio/devices/iio:device1/in_voltage0_raw 2620 real 0m 7.08s user 0m 0.00s sys 0m 0.02s # time cat /sys/bus/iio/devices/iio:device1/in_voltage1_raw 2623 real 0m 6.07s user 0m 0.01s sys 0m 0.01s # On 3.9 but using i2c-gpio to bitbang on the bus: # time cat /sys/bus/iio/devices/iio:device1/in_voltage0_raw 2661 real 0m 0.08s user 0m 0.00s sys 0m 0.06s # time cat /sys/bus/iio/devices/iio:device1/in_voltage1_raw 2270 real 0m 0.08s user 0m 0.00s sys 0m 0.05s # On 3.7, i2c-mxs: # time cat /sys/bus/iio/devices/iio:device1/in_voltage0_raw 2643 real 0m 0.06s user 0m 0.01s sys 0m 0.02s # time cat /sys/bus/iio/devices/iio:device1/in_voltage1_raw 1546 real 0m 0.05s user 0m 0.00s sys 0m 0.02s # Any input would be appreciated. Regards, -- Alexandre Belloni, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
