[PATCH v3 07/17] i3c: renesas: Do not attach devices if xfer failed

[Claudiu Beznea <claudiu.beznea@kernel.org>]

From: Claudiu Beznea <claudiu.beznea.uj@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@vger.kernel.org
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
---

Changes in v3:
- none

Changes in v2:
- none, this patch is new

 drivers/i3c/master/renesas-i3c.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/i3c/master/renesas-i3c.c b/drivers/i3c/master/renesas-i3c.c
index c475d30a84c7..f96848022c45 100644
--- a/drivers/i3c/master/renesas-i3c.c
+++ b/drivers/i3c/master/renesas-i3c.c
@@ -780,10 +780,15 @@ static int renesas_i3c_daa(struct i3c_master_controller *m)
 
 	renesas_i3c_wait_xfer(i3c, xfer);
 
-	newdevs = GENMASK(i3c->maxdevs - cmd->rx_count - 1, first_i3c_pos);
-	/* Re-attach all the I3C devices on resume. */
-	if (!i3c->resuming)
-		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, first_i3c_pos);
+		/* Re-attach all the I3C devices on resume. */
+		if (!i3c->resuming)
+			newdevs &= ~olddevs;
+	}
 
 	for (pos = 0; pos < i3c->maxdevs; pos++) {
 		if (!(newdevs & BIT(pos)))
-- 
2.43.0