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charset="UTF-8" Hi Mika, On Mon, Nov 09, 2026 at 11:20:06AM +0100, Mika Westerberg wrote: > > + if (tx_hold) { > > + regmap_read(dev->map, DW_IC_CLR_RD_REQ, &dummy); > > + regmap_read(dev->map, DW_IC_CLR_TX_ABRT, &dummy); > > + regmap_write(dev->map, DW_IC_DATA_CMD, 0xFF); > > I'm not super familiar with the slave mode so adding Heikki just in case. > Can this cause some unintended traffic on the bus towards the master? No, it cannot initiate new traffic. DW_IC_STATUS_SLAVE_HOLD_TX_FIFO_EMPTY is only asserted when an external master has already addressed this controller and initiated a read transfer, and the slave hardware is actively stretching SCL low waiting for TX data. When no slave read hold is active, i2c_dw_release_slave_hold() returns early without writing to DW_IC_DATA_CMD. Writing 0xff simply satisfies the ongoing master-clocked read byte while keeping SDA passively high (released via pull-ups), allowing the external master to finish clocking the byte and terminate the transfer with NACK/STOP instead of hanging the bus indefinitely. > Also use 0xff instead. Ack, I will update 0xFF to 0xff (and wait to see if Heikki has any comments before sending v2). Thanks, Atif