Linux/DS90UB954-Q1EVM: MIPI I2C Write read reg configuration

Hello Dorin,

It sounds like some sort of I2C driver issue. Does your driver support I2C clock stretching? What Nvidia hardware are you using? TX2?

Best Regards,

Casey 

Xavier

Hello Dorin,

Our third party partners like Leopard Imaging or D3 may be able to assist with Linux drivers for Tegra. They have worked with us in the past on several platforms for TX2 already which should be very similar. Please verify that your driver supports I2C clock stretching. 

Best Regards,
Casey 

Hi,

the Xavier and DeSerialize EVM are connected to the same I2C bus but the serializer EVM + cmos sensor are connected to a different, (fakra cable is connecting the EVM's)

so i don't understand how could it be a problem with the Xavier, in addition i manage to read and write from the serializer by I2C so could it be something that i need to change in the serializer?

it seems to me a problem with read and write addresses (I2C protocol read 'address', write 'address+1') I have only succeeded to read from the cmos so maybe the serializer doesn't pass the command with the correct write address ?

Dorin

Hello Dorin,

Do you have both ALP and the Nvidia board connected at the same time? Maybe there is some conflict between the masters? Can you please try doing register writes using just ALP by itself with your same configuration? 

Best Regards,

Casey

there is no conflict between the masters because we did this separately,

one option is to use I2C through MIPI connector on Desirializer with no usb cable connected to the ALP (we succeeded only write command from CMOS)

the second option is to use usb cable connected to the ALP (we succeeded only read command from CMOS)

is there any option to read and write from the cmos while the SerDes connected to Xavier ?

I add the opening of the script I use:
# Set up IDs
UB954 = 0x60 #0x7A
UB953ID = 0x30
UB953 = 0x30 #0x18
sensorID = 0xC0
sensorAlias = 0xC0

# Set up Port0
board.WriteI2C(UB954, 0x4C, 0x01)

# Set up Back Channel Config (0x58)
board.WriteI2C(UB954,0x58,0x5E)

# Set up SER ID
board.WriteI2C(UB954,0x5B,UB953ID)
# Set up SER Alias ID
board.WriteI2C(UB954,0x5C,UB953)
# Set up Slave/Camera ID
board.WriteI2C(UB954,0x5D,sensorID)
# Set up Slave/Camera Alias ID
board.WriteI2C(UB954,0x65,sensorAlias)

# Set General config - 2-lane configuration
board.WriteI2C(UB953,0x02,0x13)
# Set GPIO2 and GPIO3 to outputs, where GPIO2 = RESET and GPIO3 = PWDN
board.WriteI2C(UB953,0x0E,0xC0)
# Set GPIO2 and GPIO3 to High - bring sensor out of power down mode
board.WriteI2C(UB953,0x0D,0x0C)
#time.sleep(0.1)
time.sleep(5)
# Bring GPIO3 low to place sensor in reset
board.WriteI2C(UB953,0x0D,0x08)
time.sleep(1)
# Bring GPIO3 high again to prepare sensor for initialization
board.WriteI2C(UB953,0x0D,0x0C)
print "Sensor Reset"

board.WriteI2C(sensorAlias,0x01, [0x03,0x01])

board.Read2C(sensorAlias,0x01, 0x03)

those are the read/write command I use on the cmos and only the write works from the ALP

Dorin

Hello Dorin,

Does your sensor use 16 bit I2C addresses? It looks like your write command is using a 16 bit address with an 8 bit register contents:

board.WriteI2C(sensorAlias,0x01, [0x03,0x01])

Should be writing 0x01 to register 0x0103, while 

board.Read2C(sensorAlias,0x01, 0x03)

Is reading 3 bytes from register 0x01. I think you actually want to read an 8 bit value from a 16 bit register right? So if you want to read back what you just wrote to register 0x0103 you would use:

board.Read2C(sensorAlias,0x01, [0x03, 0x01])

Best Regards,

Casey 

Hey Dorin,

Any feedback? Is this issue resolved with the above?

Thanks,

Casey 

Hi,

this didn't work, the ALP wrote an error when I used this command

board.Read2C(sensorAlias,0x01, [0x03, 0x01])