[PATCH v2 07/17] i3c: renesas: Do not attach devices if xfer failed

[Claudiu Beznea]

From: Claudiu Beznea <claudiu.beznea.uj at bp.renesas.com>

The controller may return an NRSPQP_ERROR_* error code while still
providing a valid cmd->rx_count. It has been observed that when the
transfer fails with NRSPQP_ERROR_ADDRESS_NACK, calling
i3c_master_add_i3c_dev_locked() may lead to crashes. Set newdevs to zero
if the transfer failed.

Fixes: e7218986319b ("i3c: renesas: Add suspend/resume support")
Cc: stable at vger.kernel.org
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj at bp.renesas.com>
---

Changes in v2:
- none, this patch is new

 drivers/i3c/master/renesas-i3c.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/i3c/master/renesas-i3c.c b/drivers/i3c/master/renesas-i3c.c
index 695aae6ac263..de09f0cadb72 100644
--- a/drivers/i3c/master/renesas-i3c.c
+++ b/drivers/i3c/master/renesas-i3c.c
@@ -727,8 +727,13 @@ static int renesas_i3c_daa(struct i3c_master_controller *m)
 
 	renesas_i3c_wait_xfer(i3c, xfer);
 
-	newdevs = GENMASK(i3c->maxdevs - cmd->rx_count - 1, 0);
-	newdevs &= ~olddevs;
+	/* Skip attaching if there are failures on the xfer. */
+	if (xfer->ret) {
+		newdevs = 0;
+	} else {
+		newdevs = GENMASK(i3c->maxdevs - cmd->rx_count - 1, 0);
+		newdevs &= ~olddevs;
+	}
 
 	for (pos = 0; pos < i3c->maxdevs; pos++) {
 		if (newdevs & BIT(pos))
-- 
2.43.0