i2c: designware: Handle invalid SMBus block data response length value
In the I2C_FUNC_SMBUS_BLOCK_DATA case, the invalid length byte value (outside of 1-32) of the SMBus block data response from the Slave device is not correctly handled by the I2C Designware driver. In case IC_EMPTYFIFO_HOLD_MASTER_EN==1, which cannot be detected from the registers, the Master can be disabled only if the STOP bit is set. Without STOP bit set, the Master remains active, holding the bus until receiving a block data response length. This hangs the bus and is unrecoverable. Avoid this by issuing another dump read to reach the stop condition when an invalid length byte is received. Cc: stable@vger.kernel.org Signed-off-by: Tam Nguyen <tamnguyenchi@os.amperecomputing.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Link: https://lore.kernel.org/r/20230726080001.337353-3-tamnguyenchi@os.amperecomputing.com Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org>
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