docs:i2c: Add Port mapping

Signed-off-by: Ajay Bhargav <[email protected]>

Author: ajaybhargav

docs/book/api/peri/i2c.rst

@@ -1,5 +1,24 @@
 I2C
 ===
+.. |br| raw:: html
+
+	<br>
+
+I2C Port Mapping
+----------------
+
+GSM (MT2503, MT6261) and NB-IoT (MT2625) chipset supported modules expose only one
+I2C port. Following is the pin mapping for SCL and SDA:
+
++---------+------------------+-----------+-----------------+-----------+------------+------------+
+| I2C Pin |  MC20U Pin       |  M56 Pin  |  MC60 Pin       |  M66 Pin  |  BC20 Pin  |  SIM868    |
+|         |  |br| S20U Pin   |           |  |br| MC20 Pin  |           |            |  Pin       |
++=========+==================+===========+=================+===========+============+============+
+| SCL     |  Pin 35          |  Pin 24   |  Pin 35         |  Pin 20   |  Pin 58    |  Pin 65    |
++---------+------------------+-----------+-----------------+-----------+------------+------------+
+| SDA     |  Pin 36          |  Pin 23   |  Pin 36         |  Pin 21   |  Pin 63    |  Pin 64    |
++---------+------------------+-----------+-----------------+-----------+------------+------------+
+
 
 API Reference
 -------------