From: Corey Minyard <minyard@xxxxxxx> When being a target, NAK from the controller means that all bytes have been transferred. So, the last byte needs also to be marked as 'processed'. Otherwise index registers of backends may not increase. Signed-off-by: Corey Minyard <minyard@xxxxxxx> Tested-by: Andrew Manley <andrew.manley@xxxxxxxxxxxxxxx> Reviewed-by: Andrew Manley <andrew.manley@xxxxxxxxxxxxxxx> Reviewed-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx> [wsa: fixed comment and commit message to properly describe the case] Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx> --- Changes since v2: * updated commit message and comment In the stalled discussion[1], it seems I couldn't make my suggestions clear. So, here are the changes how I meant them. I hope this can be agreed on. [1] http://patchwork.ozlabs.org/project/linux-i2c/patch/20211112133956.655179-3-minyard@xxxxxxx/ drivers/i2c/busses/i2c-imx.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index 88a053987403..60e813137f84 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -803,6 +803,11 @@ static irqreturn_t i2c_imx_slave_handle(struct imx_i2c_struct *i2c_imx, ctl &= ~I2CR_MTX; imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR); imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); + + /* flag the last byte as processed */ + i2c_imx_slave_event(i2c_imx, + I2C_SLAVE_READ_PROCESSED, &value); + i2c_imx_slave_finish_op(i2c_imx); return IRQ_HANDLED; } -- 2.43.0
