+ linux-arm-kernel@xxxxxxxxxxxxxxxxxxx On 2015-07-09 16:59, Kefeng Wang wrote: > Hi all, > > We met a issue when use Synopsys DesignWare I2C. The SDA will keep low level and never go back to the high level > if both i2c controllers simultaneously access the same i2c device(rtc), then both two i2c controllers can't send any data. > we try to reset the rtc, but not working. After reset the i2c controller, the SDA goes back to the high state and we > can get time from rtc again. > > The scenario is as follows, any advice will be appreciated. > > OS 1 | OS 2 > | > +--------------+----------|--------------+ > | | | | > | +---------|----+-----|---------+ | > | | | | | | | > ---------------- ------ | ----------------- > |i2c controller1| | rtc| | |i2c controller2| > ---------------- ------ | ----------------- > | > note: > 1) i2c controller1 and controller2 use same IP. > 2) OS1 use v3.19 and OS2 use 2.6 > > Thanks > Kefeng > -- 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
