Linux/AM3359: How to force the I2C clock

Hi,

Are you sure that it's the AM335x that's holding the SDA low, and not the external device?

I think that it is the external device that is holding the SDA signal ( sorry for my english), And I'm trying to find a solution to unblock this situation.

Is there a way to force the clock ? That way the external device will finish the transmission. Or an another solution ?

I found that :

clocking 8 times for remaining incoming bits, then sending a NACK and a STOP makes the slave release the SDA line

I'm going to use the register : I2C_SYSTEST.

This is the value of the register I2C_ SYSTEST : 110100000 :
SDA_O_FUNC=1
SCL_O_FUNC =1
SCL_I_FUNC=1

Il will put ST_EN =1 and maybe TMODE in Mode = "Test of SCL counters" , because I already configured the clock before, so if I enable this mode, the SCL will be driven automatically ? I will try !

And with the register I2C_SYSTEST It dosn't looks like possible to toggling the SCL 9 time because I can force the 0 value or high impedance state, but not 1 :

SCL line drive output value.
In normal functional mode (ST_EN = 0), this bit is don't care.
It always reads 0 and a write is ignored.
In system test mode (ST_EN = 1 and TMODE = 11), a 0 forces a
low level on the SCL line and a 1 puts the I2C output driver to a
high-impedance state.
Value after reset is low.
0x0 = Forces 0 on the SCL data line
0x1 = SCL output driver in high-impedance state

Thx for the help, normally:

switching between 0xB005 and 0xB001 in the SYSTEST register should toggle the SCL line ? I put the SDA line in high impedance.

Yes, this should do it, except I believe bit 14 should be set to 1 too.