[PATCH v6 2/6] i3c: master: svc: manually emit NACK/ACK for hotjoin

[Frank Li]

When the address is arbitrated at send address, the hardware can auto-send
NACK if it is an IBI. However, manual emission of NACK/ACK is needed for
hot join or controller request events.

Add help function svc_i3c_master_handle_ibi_won() to check event type and
send out NACK if the event is not an IBI.

Reviewed-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
---
Change form v4 to v6
- none
change from v3 to v4
- add Miquel review tag
---
 drivers/i3c/master/svc-i3c-master.c | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index 7cd3ce2643f1a..c35a228f0c2f4 100644
--- a/drivers/i3c/master/svc-i3c-master.c
+++ b/drivers/i3c/master/svc-i3c-master.c
@@ -409,6 +409,24 @@ static void svc_i3c_master_nack_ibi(struct svc_i3c_master *master)
 	       master->regs + SVC_I3C_MCTRL);
 }
 
+static int svc_i3c_master_handle_ibi_won(struct svc_i3c_master *master, u32 mstatus)
+{
+	u32 ibitype;
+
+	ibitype = SVC_I3C_MSTATUS_IBITYPE(mstatus);
+
+	writel(SVC_I3C_MINT_IBIWON, master->regs + SVC_I3C_MSTATUS);
+
+	/* Hardware can't auto emit NACK for hot join and master request */
+	switch (ibitype) {
+	case SVC_I3C_MSTATUS_IBITYPE_HOT_JOIN:
+	case SVC_I3C_MSTATUS_IBITYPE_MASTER_REQUEST:
+		svc_i3c_master_nack_ibi(master);
+	}
+
+	return 0;
+}
+
 static void svc_i3c_master_ibi_work(struct work_struct *work)
 {
 	struct svc_i3c_master *master = container_of(work, struct svc_i3c_master, ibi_work);
@@ -1177,7 +1195,7 @@ static int svc_i3c_master_xfer(struct svc_i3c_master *master,
 		 * start.
 		 */
 		if (SVC_I3C_MSTATUS_IBIWON(reg)) {
-			writel(SVC_I3C_MINT_IBIWON, master->regs + SVC_I3C_MSTATUS);
+			svc_i3c_master_handle_ibi_won(master, reg);
 			continue;
 		}
 

-- 
2.34.1