Re: [PATCH V7 2/2] i2c: i2c-qcom-geni: Add shutdown callback for i2c

From: Akash Asthana
Date: Wed Dec 30 2020 - 04:27:40 EST



On 12/21/2020 6:08 PM, Roja Rani Yarubandi wrote:
If the hardware is still accessing memory after SMMU translation
is disabled (as part of smmu shutdown callback), then the
IOVAs (I/O virtual address) which it was using will go on the bus
as the physical addresses which will result in unknown crashes
like NoC/interconnect errors.

So, implement shutdown callback to i2c driver to stop on-going transfer
and unmap DMA mappings during system "reboot" or "shutdown".

Fixes: 37692de5d523 ("i2c: i2c-qcom-geni: Add bus driver for the Qualcomm GENI I2C controller")
Signed-off-by: Roja Rani Yarubandi <rojay@xxxxxxxxxxxxxx>
Reviewed-by: Akash Asthana <akashast@xxxxxxxxxxxxxx>

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