[PATCH v4 2/6] i3c: master: svc: add hot join support

[Frank Li <Frank.Li@nxp.com>]

Add hot join support for svc master controller. Enable hot join defaultly.
User can use sys entry to disable hot join.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/i3c/master/svc-i3c-master.c | 58 +++++++++++++++++++++++++++--
 1 file changed, 54 insertions(+), 4 deletions(-)

diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index 6b6bdd163af4f..880c6ae76c013 100644
--- a/drivers/i3c/master/svc-i3c-master.c
+++ b/drivers/i3c/master/svc-i3c-master.c
@@ -128,6 +128,9 @@
 /* This parameter depends on the implementation and may be tuned */
 #define SVC_I3C_FIFO_SIZE 16
 
+#define SVC_I3C_EVENT_IBI	BIT(0)
+#define SVC_I3C_EVENT_HOTJOIN	BIT(1)
+
 struct svc_i3c_cmd {
 	u8 addr;
 	bool rnw;
@@ -176,6 +179,7 @@ struct svc_i3c_regs_save {
  * @ibi.tbq_slot: To be queued IBI slot
  * @ibi.lock: IBI lock
  * @lock: Transfer lock, protect between IBI work thread and callbacks from master
+ * @enabled_events: Bit masks for enable events (IBI, HotJoin).
  */
 struct svc_i3c_master {
 	struct i3c_master_controller base;
@@ -205,6 +209,7 @@ struct svc_i3c_master {
 		spinlock_t lock;
 	} ibi;
 	struct mutex lock;
+	int enabled_events;
 };
 
 /**
@@ -428,13 +433,16 @@ static void svc_i3c_master_ibi_work(struct work_struct *work)
 	switch (ibitype) {
 	case SVC_I3C_MSTATUS_IBITYPE_IBI:
 		dev = svc_i3c_master_dev_from_addr(master, ibiaddr);
-		if (!dev)
+		if (!dev || !(master->enabled_events & SVC_I3C_EVENT_IBI))
 			svc_i3c_master_nack_ibi(master);
 		else
 			svc_i3c_master_handle_ibi(master, dev);
 		break;
 	case SVC_I3C_MSTATUS_IBITYPE_HOT_JOIN:
-		svc_i3c_master_ack_ibi(master, false);
+		if (master->enabled_events & SVC_I3C_EVENT_HOTJOIN)
+			svc_i3c_master_ack_ibi(master, false);
+		else
+			svc_i3c_master_nack_ibi(master);
 		break;
 	case SVC_I3C_MSTATUS_IBITYPE_MASTER_REQUEST:
 		svc_i3c_master_nack_ibi(master);
@@ -471,7 +479,9 @@ static void svc_i3c_master_ibi_work(struct work_struct *work)
 		svc_i3c_master_emit_stop(master);
 		break;
 	case SVC_I3C_MSTATUS_IBITYPE_HOT_JOIN:
-		queue_work(master->base.wq, &master->hj_work);
+		svc_i3c_master_emit_stop(master);
+		if (master->enabled_events & SVC_I3C_EVENT_HOTJOIN)
+			queue_work(master->base.wq, &master->hj_work);
 		break;
 	case SVC_I3C_MSTATUS_IBITYPE_MASTER_REQUEST:
 	default:
@@ -1471,6 +1481,7 @@ static int svc_i3c_master_enable_ibi(struct i3c_dev_desc *dev)
 		return ret;
 	}
 
+	master->enabled_events |= SVC_I3C_EVENT_IBI;
 	svc_i3c_master_enable_interrupts(master, SVC_I3C_MINT_SLVSTART);
 
 	return i3c_master_enec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
@@ -1482,7 +1493,9 @@ static int svc_i3c_master_disable_ibi(struct i3c_dev_desc *dev)
 	struct svc_i3c_master *master = to_svc_i3c_master(m);
 	int ret;
 
-	svc_i3c_master_disable_interrupts(master);
+	master->enabled_events &= ~SVC_I3C_EVENT_IBI;
+	if (!master->enabled_events)
+		svc_i3c_master_disable_interrupts(master);
 
 	ret = i3c_master_disec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
 
@@ -1492,6 +1505,39 @@ static int svc_i3c_master_disable_ibi(struct i3c_dev_desc *dev)
 	return ret;
 }
 
+static int svc_i3c_master_enable_hotjoin(struct i3c_master_controller *m)
+{
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+	int ret;
+
+	ret = pm_runtime_resume_and_get(master->dev);
+	if (ret < 0) {
+		dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
+		return ret;
+	}
+
+	master->enabled_events |= SVC_I3C_EVENT_HOTJOIN;
+
+	svc_i3c_master_enable_interrupts(master, SVC_I3C_MINT_SLVSTART);
+
+	return 0;
+}
+
+static int svc_i3c_master_disable_hotjoin(struct i3c_master_controller *m)
+{
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+
+	master->enabled_events &= ~SVC_I3C_EVENT_HOTJOIN;
+
+	if (!master->enabled_events)
+		svc_i3c_master_disable_interrupts(master);
+
+	pm_runtime_mark_last_busy(master->dev);
+	pm_runtime_put_autosuspend(master->dev);
+
+	return 0;
+}
+
 static void svc_i3c_master_recycle_ibi_slot(struct i3c_dev_desc *dev,
 					    struct i3c_ibi_slot *slot)
 {
@@ -1518,6 +1564,8 @@ static const struct i3c_master_controller_ops svc_i3c_master_ops = {
 	.recycle_ibi_slot = svc_i3c_master_recycle_ibi_slot,
 	.enable_ibi = svc_i3c_master_enable_ibi,
 	.disable_ibi = svc_i3c_master_disable_ibi,
+	.enable_hotjoin = svc_i3c_master_enable_hotjoin,
+	.disable_hotjoin = svc_i3c_master_disable_hotjoin,
 };
 
 static int svc_i3c_master_prepare_clks(struct svc_i3c_master *master)
@@ -1630,6 +1678,8 @@ static int svc_i3c_master_probe(struct platform_device *pdev)
 	pm_runtime_mark_last_busy(&pdev->dev);
 	pm_runtime_put_autosuspend(&pdev->dev);
 
+	i3c_master_enable_hotjoin(&master->base);
+
 	return 0;
 
 rpm_disable:
-- 
2.34.1