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If the i3c device boots slowly, it might be miss the DDA during boot. > > > > Signed-off-by: David Nyström > > --- > > Can we rename rescan to something where indicate we are only doing ENTDAA? I think rescan keyword should be reserved for complete rescan of i3c bus. > DISEC -> RSTDAA -> ENTDAA -> ... Look like this is more userful. The only do_daa() is not enough for rescan. Frank > > > Changes in v2: > > - Improved the commit message with "why". > > - Link to v1: https://patch.msgid.link/20260122-i3c_rescan-v1-1-0c17071e232b@est.tech > > --- > > drivers/i3c/master.c | 24 ++++++++++++++++++++++++ > > 1 file changed, 24 insertions(+) > > > > diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c index 80dda0e85558..edeae7493b3b 100644 > > --- a/drivers/i3c/master.c > > +++ b/drivers/i3c/master.c > > @@ -758,6 +758,29 @@ static ssize_t dev_nack_retry_count_store(struct device *dev, > > > > static DEVICE_ATTR_RW(dev_nack_retry_count); > > > > +static ssize_t rescan_store(struct device *dev, > > + struct device_attribute *attr, > > + const char *buf, size_t count) > > +{ > > + struct i3c_master_controller *master = dev_to_i3cmaster(dev); > > + unsigned long val; > > + int ret; > > + > > + ret = kstrtoul(buf, 0, &val); > > + if (ret) > > + return ret; > > + > > + if (val) { > > + ret = i3c_master_do_daa(master); > > + if (ret) > > + return ret; > > + } > > + > > + return count; > > +} > > + > > +static DEVICE_ATTR_WO(rescan); > > + > > static struct attribute *i3c_masterdev_attrs[] = { > > &dev_attr_mode.attr, > > &dev_attr_current_master.attr, > > @@ -769,6 +792,7 @@ static struct attribute *i3c_masterdev_attrs[] = { > > &dev_attr_dynamic_address.attr, > > &dev_attr_hdrcap.attr, > > &dev_attr_hotjoin.attr, > > + &dev_attr_rescan.attr, > > NULL, > > }; > > ATTRIBUTE_GROUPS(i3c_masterdev); > > > > --- > > base-commit: e3b32dcb9f23e3c3927ef3eec6a5842a988fb574 > > change-id: 20260116-i3c_rescan-4921d0b41a00 > > > > Best regards, > > -- > > David Nyström > > > > > > -- > > linux-i3c mailing list > > linux-i3c@lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/linux-i3c