TDA4VM: I2C recover when in polling mode

up

Hi Subin li,

Could you pls help us understand the issue that you are facing? Do you see i2c bus getting blocked in polling mode? What's the value of the timeout you are using?

Regards,

Brijesh

Hi Brijesh

sometimes we found I2C_transfer() return I2C_STS_ERR_TIMEOUT. and from I2C_SYSTEST register, we found the SCL_I_FUNC is stuck low and it won't recover.

I found there is I2C_v1_recoverBus() in I2C driver, but it won't be called when I2C is in  I2C_OPER_MODE_POLLING  mode.

so I want to know how to restore I2C when this kind of problem occurs.

thank you

Hello Subin li,

But why does it timeout? Are you setting enough timeout value or i2c client not responding? I am just trying to see if the issue is something else.

Even if we call recover API, the issue might come back again.

Regards,

Brijesh 

Hi Brijesh 

our timeout value is 500ms.

We will have some bad scenarios for testing，such as EMC test. In these cases, the i2c client may have some problem, and it may lead to the SCL_I_FUNC is stuck low.

In these cases, we want the I2C can be recovered.

and we also found that after calling I2C_v1_recoverBus(), the SCL_I_FUNC  restore to high, but I2C communication still timed out.

by the way, is there any way to confirm the exact cause of the timeout?

thank you

up

Hi Subil li,

Do you mean even after adding recover bus API, the bus is not recovering? Could you please check if client device is sending ACK? 

Regards,

Brijesh

Hi Brijesh

yes, after adding recover bus API, the bus is not recovering.

but I am not sure whether the client device is sending ack, I will check it next time.

after recover bus, all client device registers are still inaccessible, so I think it’s not that a single device has a problem.

Hi Subin li,

I think there is an option in the driver to not wait for the ACK. can you try with this option? 

Regards,

Brijesh

you mean the callback mode?

Hi Brijesh

We haven’t reproduced the timeout problem yet.

the first quextion, when we set the operMode to I2C_OPER_MODE_POLLING, if timeout happen, whether the I2C_recoverBus() should be called?

thank you

up

Hi, Brijesh

I'm so sad that I haven't heard from you for too long.

We have solved other problems. But there is still a question, when we set the operMode to I2C_OPER_MODE_POLLING, if timeout happen, whether the I2C_recoverBus() should be called?

Should I add an I2C recovery operation when in I2C_OPER_MODE_POLLING mode?

Regards,

subin