Re: [PATCH v3] i2c: bcm-iproc: Add i2c recovery support

Wolfram Sang
2021-11-29T19:03:18Z

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Hi Chris,

sorry for the long delay.

All looks good except for this:

> @@ -806,6 +954,7 @@ static int bcm_iproc_i2c_xfer_wait(struct bcm_iproc_i2c_dev *iproc_i2c,
> /* flush both TX/RX FIFOs */
> val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);
> iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
> + iproc_i2c_lockup_recover(iproc_i2c);
> return -ETIMEDOUT;
> }
>
> @@ -814,6 +963,7 @@ static int bcm_iproc_i2c_xfer_wait(struct bcm_iproc_i2c_dev *iproc_i2c,
> /* flush both TX/RX FIFOs */
> val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);
> iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
> + iproc_i2c_lockup_recover(iproc_i2c);
> return ret;
> }

I2C specs suggest recovery at the beginning of a transfer when SDA is
detected low. Not at the end of a transfer.

Happy hacking,

Wolfram

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