Hi Jan, On jeu., août 23 2018, Jan Kundrát <jan.kundrat@xxxxxxxxx> wrote: > The datasheet lists this value explicitly, so it is better to show what > exactly is going on rather than falling back to a generic message. That > generic message was correct and included all details, but at the same > time it required one to dig the datasheet to understand that 0x00 = > "slave touched the bus when it should not have done so". > > Signed-off-by: Jan Kundrát <jan.kundrat@xxxxxxxxx> > --- > drivers/i2c/busses/i2c-mv64xxx.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c > index a5a95ea5b81a..469374ded7ae 100644 > --- a/drivers/i2c/busses/i2c-mv64xxx.c > +++ b/drivers/i2c/busses/i2c-mv64xxx.c > @@ -317,6 +317,14 @@ mv64xxx_i2c_fsm(struct mv64xxx_i2c_data *drv_data, u32 status) > drv_data->rc = -ENXIO; > break; > > + case MV64XXX_I2C_STATUS_BUS_ERR: /* 0x00 */ > + dev_warn(&drv_data->adapter.dev, > + "bus error: slave has driven SDA/SCL unexpectedly\n"); > + drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP; > + mv64xxx_i2c_hw_init(drv_data); > + drv_data->rc = -EIO; > + break; > + Actually you do the same thing that we have in the default case but with a different warning message. In this case What about just keeping this line and then go through the default case ? + case MV64XXX_I2C_STATUS_BUS_ERR: /* 0x00 */ + dev_warn(&drv_data->adapter.dev, + "bus error: slave has driven SDA/SCL unexpectedly\n"); But actually according to the datasheet we don't have to reset hardware and initialize FSM. The only request actions are "setting the Stop field in the I2C Control Register and clearing the interrupt." For your patch that would mean removing the "mv64xxx_i2c_hw_init(drv_data);" line. Could you test it? Thanks, Gregory > default: > dev_err(&drv_data->adapter.dev, > "mv64xxx_i2c_fsm: Ctlr Error -- state: 0x%x, " > -- > 2.18.0 > > -- Gregory Clement, Bootlin Embedded Linux and Kernel engineering http://bootlin.com
