[PATCH 6.6 302/567] i3c: dw-i3c-master: Set SIR_REJECT in DAT on device attach and reattach

Greg Kroah-Hartman
2026-03-23T15:07:00Z

6.6-stable review patch. If anyone has any objections, please let me know.

------------------

From: Adrian Ng Ho Yin <adrianhoyin.ng@altera.com>

[ Upstream commit f311a05784634febd299f03476b80f3f18489767 ]

The DesignWare I3C master controller ACKs IBIs as soon as a valid
Device Address Table (DAT) entry is present. This can create a race
between device attachment (after DAA) and the point where the client
driver enables IBIs via i3c_device_enable_ibi().

Set DEV_ADDR_TABLE_SIR_REJECT in the DAT entry during
attach_i3c_dev() and reattach_i3c_dev() so that IBIs are rejected
by default. The bit is managed thereafter by the existing
dw_i3c_master_set_sir_enabled() function, which clears it in
enable_ibi() after ENEC is issued, and restores it in disable_ibi()
after DISEC.

Fixes: 1dd728f5d4d4 ("i3c: master: Add driver for Synopsys DesignWare IP")
Signed-off-by: Adrian Ng Ho Yin <adrianhoyin.ng@altera.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://patch.msgid.link/53f5b8cbdd8af789ec38b95b02873f32f9182dd6.1770962368.git.adrianhoyin.ng@altera.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/i3c/master/dw-i3c-master.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
index cee2805fccd0f..ccb521bcb73e3 100644
--- a/drivers/i3c/master/dw-i3c-master.c
+++ b/drivers/i3c/master/dw-i3c-master.c
@@ -941,7 +941,7 @@ static int dw_i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev,
master->free_pos &= ~BIT(pos);
}

- writel(DEV_ADDR_TABLE_DYNAMIC_ADDR(dev->info.dyn_addr),
+ writel(DEV_ADDR_TABLE_DYNAMIC_ADDR(dev->info.dyn_addr) | DEV_ADDR_TABLE_SIR_REJECT,
master->regs +
DEV_ADDR_TABLE_LOC(master->datstartaddr, data->index));

@@ -970,7 +970,7 @@ static int dw_i3c_master_attach_i3c_dev(struct i3c_dev_desc *dev)
master->free_pos &= ~BIT(pos);
i3c_dev_set_master_data(dev, data);

- writel(DEV_ADDR_TABLE_DYNAMIC_ADDR(master->devs[pos].addr),
+ writel(DEV_ADDR_TABLE_DYNAMIC_ADDR(master->devs[pos].addr) | DEV_ADDR_TABLE_SIR_REJECT,
master->regs +
DEV_ADDR_TABLE_LOC(master->datstartaddr, data->index));

--
2.51.0