in nRF54L15 getting I2C error code as -5, unable to communicate with I2C peripheral.

[sravan.rikka]

Hi Team,

Below function returns error code as -5 and unable to write and read data from I2C peripheral.

err = i2c_write_read(i2c_dev, addr, write_data, write_size, read_data, read_size);

#define  EIO 5    /* I/O error */

Can you please provide your inputs to resolve this I2C issue.

Regards,

Sravan Rikka

[Edvin]

Hello Sravan,

What NCS version are you using?

Is there a way for me to reproduce what you are seeing on a DK?

Best regards,

Edvin

[sravan.rikka]

Hi Edvin,

We are using SDK 3.1.0, we are using our custom board.

Regards,

Sravan Rikka

[Edvin]

Thank you! 

Have you tried reproducing the issue on a DK? Or stepped into the i2c_nrfx_twim_transfer() in v3.1.1\zephyr\drivers\i2c\i2c_nrfx_twim.c, which is ultimately called from i2c_write_read() to see why it returns -5 (-EIO)?

This is the full function:

static int i2c_nrfx_twim_transfer(const struct device *dev,
				  struct i2c_msg *msgs,
				  uint8_t num_msgs, uint16_t addr)
{
	struct i2c_nrfx_twim_data *dev_data = dev->data;
	const struct i2c_nrfx_twim_common_config *dev_config = dev->config;
	int ret = 0;
	uint8_t *msg_buf = dev_config->msg_buf;
	uint16_t msg_buf_used = 0;
	uint16_t msg_buf_size = dev_config->msg_buf_size;
	uint8_t *buf;
	uint16_t buf_len;

	(void)i2c_nrfx_twim_exclusive_access_acquire(dev, K_FOREVER);

	/* Dummy take on completion_sync sem to be sure that it is empty */
	k_sem_take(&dev_data->completion_sync, K_NO_WAIT);

	for (size_t i = 0; i < num_msgs; i++) {
		if (I2C_MSG_ADDR_10_BITS & msgs[i].flags) {
			ret = -ENOTSUP;
			break;
		}

		bool dma_accessible = nrf_dma_accessible_check(&dev_config->twim, msgs[i].buf);

		/* This fragment needs to be merged with the next one if:
		 * - it is not the last fragment
		 * - it does not end a bus transaction
		 * - the next fragment does not start a bus transaction
		 * - the direction of the next fragment is the same as this one
		 */
		bool concat_next = ((i + 1) < num_msgs)
				&& !(msgs[i].flags & I2C_MSG_STOP)
				&& !(msgs[i + 1].flags & I2C_MSG_RESTART)
				&& ((msgs[i].flags & I2C_MSG_READ)
				    == (msgs[i + 1].flags & I2C_MSG_READ));

		/* If we need to concatenate the next message, or we've
		 * already committed to concatenate this message, or its buffer
		 * is not accessible by DMA, add it to the internal driver
		 * buffer after verifying there's room.
		 */
		if (concat_next || (msg_buf_used != 0) || !dma_accessible) {
			if ((msg_buf_used + msgs[i].len) > msg_buf_size) {
				LOG_ERR("Need to use the internal driver "
					"buffer but its size is insufficient "
					"(%u + %u > %u). "
					"Adjust the zephyr,concat-buf-size or "
					"zephyr,flash-buf-max-size property "
					"(the one with greater value) in the "
					"\"%s\" node.",
					msg_buf_used, msgs[i].len,
					msg_buf_size, dev->name);
				ret = -ENOSPC;
				break;
			}
			if (!(msgs[i].flags & I2C_MSG_READ)) {
				memcpy(msg_buf + msg_buf_used,
				       msgs[i].buf,
				       msgs[i].len);
			}
			msg_buf_used += msgs[i].len;
		}

		if (concat_next) {
			continue;
		}

		if (msg_buf_used == 0) {
			buf = msgs[i].buf;
			buf_len = msgs[i].len;
		} else {
			buf = msg_buf;
			buf_len = msg_buf_used;
		}
		ret = i2c_nrfx_twim_msg_transfer(dev, msgs[i].flags, buf, buf_len, addr);
		if (ret < 0) {
			break;
		}

		ret = k_sem_take(&dev_data->completion_sync,
				 I2C_TRANSFER_TIMEOUT_MSEC);
		if (ret != 0) {
			/* Whatever the frequency, completion_sync should have
			 * been given by the event handler.
			 *
			 * If it hasn't, it's probably due to an hardware issue
			 * on the I2C line, for example a short between SDA and
			 * GND.
			 * This is issue has also been when trying to use the
			 * I2C bus during MCU internal flash erase.
			 *
			 * In many situation, a retry is sufficient.
			 * However, some time the I2C device get stuck and need
			 * help to recover.
			 * Therefore we always call i2c_nrfx_twim_recover_bus()
			 * to make sure everything has been done to restore the
			 * bus from this error.
			 */
			(void)i2c_nrfx_twim_recover_bus(dev);
			ret = -EIO;
			break;
		}

		if (dev_data->res != NRFX_SUCCESS) {
			ret = -EIO;
			break;
		}

		/* If concatenated messages were I2C_MSG_READ type, then
		 * content of concatenation buffer has to be copied back into
		 * buffers provided by user. */
		if ((msgs[i].flags & I2C_MSG_READ) && (buf == msg_buf)) {
			int j = i;

			while (msg_buf_used >= msgs[j].len) {
				msg_buf_used -= msgs[j].len;
				memcpy(msgs[j].buf,
				       msg_buf + msg_buf_used,
				       msgs[j].len);
				j--;
			}

		}

		msg_buf_used = 0;
	}

	i2c_nrfx_twim_exclusive_access_release(dev);

	return ret;
}

and as you can see, there are several possible routes to return -EIO. Either k_sem_take(&dev_data->completion_sync, I2C_TRANSFER_TIMEOUT_MSEC); returned an error, or dev_data->res != NRFX_SUCCESS, or possibly i2c_nrfx_twim_msg_transfer() returned -EIO.

Are you able to see which one it is? 

Best regards,

Edvin

[sravan.rikka]

Hi Edvin,

Have you tried reproducing the issue on a DK?

No, we don't have DK boards.

We are using 'i2c_write_read()' function and getting -5 from this function. Attached our test code.

Please provide your inputs to resolve this. We are stuck up in board bring up activity.

We have 5 I2C slave on board. We are able to communicate successfully and getting data from the 3 slaves but getting -5 error from two slaves. We are using 10K pullup resistor.

I2C communication code.docx

Regards,

Sravan Rikka

[Edvin]

Can you upload the full application that you are testing?

And have you checked whether there is any I2C activity on the I2C pins at all using a logic analyzer? Can you upload the logic trace as well?

Best regards,

Edvin