STM32 I2C driver "repeated start" issue

[jmchiappa]

Hello,

I'm trying to connect to the MMA8451 accelerometer. This chip requires an I2C driver with repeated-start feature enabled to discuss with.
I've a NUCLEO-F411RE, lib 1.6.1 and no repeated start is generated due to some low level limitations.
Let me explain:
XferOptions variable is always set to I2C_NO_OPTION_FRAME in the HAL_I2C_Transmit_IT. So, once the Xfer is completed, it fires I2C_MasterTransmit_TXE. As the following condition is always false (stm32f4xx_hal_i2c.c):
if ((CurrentXferOptions != I2C_FIRST_AND_LAST_FRAME) && (CurrentXferOptions != I2C_LAST_FRAME) && (CurrentXferOptions != I2C_NO_OPTION_FRAME))
a STOP will be generated (line 5025):

      /* Disable EVT, BUF and ERR interrupt */
      __HAL_I2C_DISABLE_IT(hi2c, I2C_IT_EVT | I2C_IT_BUF | I2C_IT_ERR);

      /* Generate Stop */
      SET_BIT(hi2c->Instance->CR1, I2C_CR1_STOP);

Does someone can confirm ?
How could we override XferOptions by setting to I2C_LAST_FRAME_NO_STOP ?
Ok, I understand that it's not directly related to the framework by itself, but I observed that I2C driver is really different regarding the variant.
In other word, by using TwoWire::endTransmission(false), it should not send a STOP condition (instead of UNUSED(endStop) ).

Thank you,
jean-marc

[fpistm]

Hi Jean-Marc,
thanks for the report. Will try to investigate when got a time slot. (will be on vacation soon)
Maybe @LMESTM will have a look when he came back from vacation.

[jmchiappa]

Hi Frédéric,
Thank you for your reply.
After deeper investigation, it seems that HAL_I2C_Master_Seq_Transmit_IT is more relevant to generate a 'repeated-start' as XferOptions is passed in argument list.
Curiously, this function is called HAL_I2C_Master_Sequential_Transmit_IT in F0,F1,F2,F3 series but it's correctly bind in legacy file.
I'll have a try as soon as I can (in holidays soon too).

Enjoy your holidays !

[fpistm]

Thanks, enjoy too.

The function has been renamed in newer STM32CubeFW Release for or MISRA-C 2012 compliancy:
See the Release_Notes.html

I guess at term all series will be renamed. The next cube update add this too for some of this series, see #566.

[fpistm]

Fixed by #590

[fpistm]

During non reg tests for 1.7.0 release found issue with STM32 F2 and F4 related to #590.
So I've reverted it to perform further investigation.