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CCI <strong>i2c</strong> interface of Snapdragon 820 - DragonBoard 820c - 96Boards Forum

CCI i2c interface of Snapdragon 820

Products Support DragonBoard 820c
#1

Hello there,

May I ask if there is a packet size limitation on CCI i2c pins? What is the reason CCI i2c interface cannot be used as general purpose i2c?

Many thanks.

#2

CCI is only a subset of i2c (7-bit addressing only, no multi-master support…), though it should be compatible with most of i2c devices. There is nothing preventing you to try communicating with a i2c device.

According to the driver max byte per message is 10-byte for write and 12-byte for read.

#3

Thank you very much for the reply.

So I wonder if I can just change the limitation in driver to increase the limitation? Or is this something to do with hardware?

Also do i2c interface 19 i2c1_SCL i2c1_SCL (APQ GPIO_7) and 21 i2c1_SDA i2c1_SDA (APQ GPIO_6) have the same limitation?

Is there anyway I can re-config GPIO on Dragonboard 820?

Many thanks