Lines Matching +full:our +full:- +full:claim +full:- +full:gpios
1 GPIO-based I2C Arbitration Using a Challenge & Response Mechanism
6 In many cases using GPIOs to arbitrate is not needed and a design can use
7 the standard I2C multi-master rules. Using GPIOs is generally useful in
20 All masters on the bus have a 'bus claim' line which is an output that the
21 others can see. These are all active low with pull-ups enabled. We'll
24 - OUR_CLAIM: output from us signaling to other hosts that we want the bus
25 - THEIR_CLAIMS: output from others signaling that they want the bus
31 Let's say we want to claim the bus. We:
38 5. If not, back off, release the claim and wait for a few more milliseconds.
43 - compatible: i2c-arb-gpio-challenge
44 - our-claim-gpio: The GPIO that we use to claim the bus.
45 - their-claim-gpios: The GPIOs that the other sides use to claim the bus.
47 - I2C arbitration bus node. See i2c-arb.txt in this directory.
50 - slew-delay-us: microseconds to wait for a GPIO to go high. Default is 10 us.
51 - wait-retry-us: we'll attempt another claim after this many microseconds.
53 - wait-free-us: we'll give up after this many microseconds. Default is 50000 us.
58 compatible = "acme,some-i2c-device";
59 #address-cells = <1>;
60 #size-cells = <0>;
63 i2c-arbitrator {
64 compatible = "i2c-arb-gpio-challenge";
66 i2c-parent = <&{/i2c@12CA0000}>;
68 our-claim-gpio = <&gpf0 3 1>;
69 their-claim-gpios = <&gpe0 4 1>;
70 slew-delay-us = <10>;
71 wait-retry-us = <3000>;
72 wait-free-us = <50000>;
74 i2c-arb {
75 #address-cells = <1>;
76 #size-cells = <0>;