Messages in this thread | | | Date | Tue, 2 Dec 2014 19:00:40 +0530 | Subject | Re: [PATCH 3/4] devicetree: bindings: Add defeature-repeated-start property for Cadence I2C | From | Harini Katakam <> |
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Hi,
On Tue, Dec 2, 2014 at 6:46 PM, Wolfram Sang <wsa@the-dreams.de> wrote: > >> But given the bugs, it will be useful to just disable it if the system doesn't >> require repeated start. > > What do you do when disable repeated start? Sending STOP and START? If > so, this is really something different than repeated start. By using > I2C_FUNC_I2C a user expects repeated start, so if the HW does not > support it, we should say so and don't try to emulate it with something > different. >
Yes, we send stop. Using repeated start, when number of messages passed > 1, HOLD bit is set by the driver. This is an indication to the controller not to send a STOP. If we disable repeated start, the driver will not set HOLD bit. All the messages are sent but with START and a STOP for each of them.
Regards, Harini
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