Lines Matching +full:i2c +full:- +full:arb +full:- +full:gpio +full:- +full:challenge
1 I2C Bus Arbitration
4 While I2C supports multi-master buses this is difficult to get right.
6 Clock-stretching and the arbitrary time that an I2C transaction can take
8 When one or more masters can be reset independently part-way through a
11 U-Boot provides a scheme based on two 'claim' GPIOs, one driven by the
18 Since U-Boot runs on the AP, the terminology used is 'our' claim GPIO,
19 meaning the AP's, and 'their' claim GPIO, meaning the EC's. This terminology
22 The driver is implemented as an I2C mux, as it is in Linux. See
23 i2c-arb-gpio-challenge for the implementation.
25 GPIO lines are shared between the AP and EC to manage the bus. The AP and EC
28 - AP_CLAIM: output from AP, signalling to the EC that the AP wants the bus
29 - EC_CLAIM: output from EC, signalling to the AP that the EC wants the bus
50 To release the bus, just de-assert the claim line.
53 - slew time 10 us
54 - retry time 3 ms
55 - wait time - 50ms