Linux-libre 4.8.2-gnupck-4.8.2-gnu

7 files changed, 1009 insertions, 179 deletions

diff --git a/drivers/hsi/Makefile b/drivers/hsi/Makefile
index 360371e13..96944783d 100644
--- a/drivers/hsi/Makefile
+++ b/drivers/hsi/Makefile
@@ -1,7 +1,8 @@
 #
 # Makefile for HSI
 #
-obj-$(CONFIG_HSI_BOARDINFO)	+= hsi_boardinfo.o
 obj-$(CONFIG_HSI)		+= hsi.o
+hsi-objs			:= hsi_core.o
+hsi-$(CONFIG_HSI_BOARDINFO)	+= hsi_boardinfo.o
 obj-y				+= controllers/
 obj-y				+= clients/
diff --git a/drivers/hsi/clients/cmt_speech.c b/drivers/hsi/clients/cmt_speech.c
index 95638df73..3deef6cc7 100644
--- a/drivers/hsi/clients/cmt_speech.c
+++ b/drivers/hsi/clients/cmt_speech.c
@@ -444,8 +444,8 @@ static void cs_hsi_read_on_control_complete(struct hsi_msg *msg)
 	hi->control_state &= ~SSI_CHANNEL_STATE_READING;
 	if (msg->status == HSI_STATUS_ERROR) {
 		dev_err(&hi->cl->device, "Control RX error detected\n");
-		cs_hsi_control_read_error(hi, msg);
 		spin_unlock(&hi->lock);
+		cs_hsi_control_read_error(hi, msg);
 		goto out;
 	}
 	dev_dbg(&hi->cl->device, "Read on control: %08X\n", cmd);
@@ -1275,7 +1275,7 @@ static int cs_char_mmap(struct file *file, struct vm_area_struct *vma)
 	if (vma->vm_end < vma->vm_start)
 		return -EINVAL;
 
-	if (((vma->vm_end - vma->vm_start) >> PAGE_SHIFT) != 1)
+	if (vma_pages(vma) != 1)
 		return -EINVAL;
 
 	vma->vm_flags |= VM_IO | VM_DONTDUMP | VM_DONTEXPAND;
diff --git a/drivers/hsi/clients/ssi_protocol.c b/drivers/hsi/clients/ssi_protocol.c
index 6595d2091..6031cd146 100644
--- a/drivers/hsi/clients/ssi_protocol.c
+++ b/drivers/hsi/clients/ssi_protocol.c
@@ -88,6 +88,8 @@ void ssi_waketest(struct hsi_client *cl, unsigned int enable);
 #define SSIP_READY_CMD		SSIP_CMD(SSIP_READY, 0)
 #define SSIP_SWBREAK_CMD	SSIP_CMD(SSIP_SW_BREAK, 0)
 
+#define SSIP_WAKETEST_FLAG 0
+
 /* Main state machine states */
 enum {
 	INIT,
@@ -116,7 +118,7 @@ enum {
  * @main_state: Main state machine
  * @send_state: TX state machine
  * @recv_state: RX state machine
- * @waketest: Flag to follow wake line test
+ * @flags: Flags, currently only used to follow wake line test
  * @rxid: RX data id
  * @txid: TX data id
  * @txqueue_len: TX queue length
@@ -137,7 +139,7 @@ struct ssi_protocol {
 	unsigned int		main_state;
 	unsigned int		send_state;
 	unsigned int		recv_state;
-	unsigned int		waketest:1;
+	unsigned long		flags;
 	u8			rxid;
 	u8			txid;
 	unsigned int		txqueue_len;
@@ -148,6 +150,7 @@ struct ssi_protocol {
 	struct net_device	*netdev;
 	struct list_head	txqueue;
 	struct list_head	cmdqueue;
+	struct work_struct	work;
 	struct hsi_client	*cl;
 	struct list_head	link;
 	atomic_t		tx_usecnt;
@@ -405,15 +408,17 @@ static void ssip_reset(struct hsi_client *cl)
 	spin_lock_bh(&ssi->lock);
 	if (ssi->send_state != SEND_IDLE)
 		hsi_stop_tx(cl);
-	if (ssi->waketest)
-		ssi_waketest(cl, 0);
+	spin_unlock_bh(&ssi->lock);
+	if (test_and_clear_bit(SSIP_WAKETEST_FLAG, &ssi->flags))
+		ssi_waketest(cl, 0); /* FIXME: To be removed */
+	spin_lock_bh(&ssi->lock);
 	del_timer(&ssi->rx_wd);
 	del_timer(&ssi->tx_wd);
 	del_timer(&ssi->keep_alive);
 	ssi->main_state = 0;
 	ssi->send_state = 0;
 	ssi->recv_state = 0;
-	ssi->waketest = 0;
+	ssi->flags = 0;
 	ssi->rxid = 0;
 	ssi->txid = 0;
 	list_for_each_safe(head, tmp, &ssi->txqueue) {
@@ -437,7 +442,8 @@ static void ssip_dump_state(struct hsi_client *cl)
 	dev_err(&cl->device, "Send state: %d\n", ssi->send_state);
 	dev_err(&cl->device, "CMT %s\n", (ssi->main_state == ACTIVE) ?
 							"Online" : "Offline");
-	dev_err(&cl->device, "Wake test %d\n", ssi->waketest);
+	dev_err(&cl->device, "Wake test %d\n",
+				test_bit(SSIP_WAKETEST_FLAG, &ssi->flags));
 	dev_err(&cl->device, "Data RX id: %d\n", ssi->rxid);
 	dev_err(&cl->device, "Data TX id: %d\n", ssi->txid);
 
@@ -515,17 +521,17 @@ static void ssip_start_rx(struct hsi_client *cl)
 
 	dev_dbg(&cl->device, "RX start M(%d) R(%d)\n", ssi->main_state,
 						ssi->recv_state);
-	spin_lock(&ssi->lock);
+	spin_lock_bh(&ssi->lock);
 	/*
 	 * We can have two UP events in a row due to a short low
 	 * high transition. Therefore we need to ignore the sencond UP event.
 	 */
 	if ((ssi->main_state != ACTIVE) || (ssi->recv_state == RECV_READY)) {
-		spin_unlock(&ssi->lock);
+		spin_unlock_bh(&ssi->lock);
 		return;
 	}
 	ssip_set_rxstate(ssi, RECV_READY);
-	spin_unlock(&ssi->lock);
+	spin_unlock_bh(&ssi->lock);
 
 	msg = ssip_claim_cmd(ssi);
 	ssip_set_cmd(msg, SSIP_READY_CMD);
@@ -539,10 +545,10 @@ static void ssip_stop_rx(struct hsi_client *cl)
 	struct ssi_protocol *ssi = hsi_client_drvdata(cl);
 
 	dev_dbg(&cl->device, "RX stop M(%d)\n", ssi->main_state);
-	spin_lock(&ssi->lock);
+	spin_lock_bh(&ssi->lock);
 	if (likely(ssi->main_state == ACTIVE))
 		ssip_set_rxstate(ssi, RECV_IDLE);
-	spin_unlock(&ssi->lock);
+	spin_unlock_bh(&ssi->lock);
 }
 
 static void ssip_free_strans(struct hsi_msg *msg)
@@ -559,9 +565,9 @@ static void ssip_strans_complete(struct hsi_msg *msg)
 
 	data = msg->context;
 	ssip_release_cmd(msg);
-	spin_lock(&ssi->lock);
+	spin_lock_bh(&ssi->lock);
 	ssip_set_txstate(ssi, SENDING);
-	spin_unlock(&ssi->lock);
+	spin_unlock_bh(&ssi->lock);
 	hsi_async_write(cl, data);
 }
 
@@ -666,15 +672,17 @@ static void ssip_rx_bootinforeq(struct hsi_client *cl, u32 cmd)
 		/* Fall through */
 	case INIT:
 	case HANDSHAKE:
-		spin_lock(&ssi->lock);
+		spin_lock_bh(&ssi->lock);
 		ssi->main_state = HANDSHAKE;
-		if (!ssi->waketest) {
-			ssi->waketest = 1;
+		spin_unlock_bh(&ssi->lock);
+
+		if (!test_and_set_bit(SSIP_WAKETEST_FLAG, &ssi->flags))
 			ssi_waketest(cl, 1); /* FIXME: To be removed */
-		}
+
+		spin_lock_bh(&ssi->lock);
 		/* Start boot handshake watchdog */
 		mod_timer(&ssi->tx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT));
-		spin_unlock(&ssi->lock);
+		spin_unlock_bh(&ssi->lock);
 		dev_dbg(&cl->device, "Send BOOTINFO_RESP\n");
 		if (SSIP_DATA_VERSION(cmd) != SSIP_LOCAL_VERID)
 			dev_warn(&cl->device, "boot info req verid mismatch\n");
@@ -696,14 +704,14 @@ static void ssip_rx_bootinforesp(struct hsi_client *cl, u32 cmd)
 	if (SSIP_DATA_VERSION(cmd) != SSIP_LOCAL_VERID)
 		dev_warn(&cl->device, "boot info resp verid mismatch\n");
 
-	spin_lock(&ssi->lock);
+	spin_lock_bh(&ssi->lock);
 	if (ssi->main_state != ACTIVE)
 		/* Use tx_wd as a boot watchdog in non ACTIVE state */
 		mod_timer(&ssi->tx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT));
 	else
 		dev_dbg(&cl->device, "boot info resp ignored M(%d)\n",
 							ssi->main_state);
-	spin_unlock(&ssi->lock);
+	spin_unlock_bh(&ssi->lock);
 }
 
 static void ssip_rx_waketest(struct hsi_client *cl, u32 cmd)
@@ -711,20 +719,22 @@ static void ssip_rx_waketest(struct hsi_client *cl, u32 cmd)
 	struct ssi_protocol *ssi = hsi_client_drvdata(cl);
 	unsigned int wkres = SSIP_PAYLOAD(cmd);
 
-	spin_lock(&ssi->lock);
+	spin_lock_bh(&ssi->lock);
 	if (ssi->main_state != HANDSHAKE) {
 		dev_dbg(&cl->device, "wake lines test ignored M(%d)\n",
 							ssi->main_state);
-		spin_unlock(&ssi->lock);
+		spin_unlock_bh(&ssi->lock);
 		return;
 	}
-	if (ssi->waketest) {
-		ssi->waketest = 0;
+	spin_unlock_bh(&ssi->lock);
+
+	if (test_and_clear_bit(SSIP_WAKETEST_FLAG, &ssi->flags))
 		ssi_waketest(cl, 0); /* FIXME: To be removed */
-	}
+
+	spin_lock_bh(&ssi->lock);
 	ssi->main_state = ACTIVE;
 	del_timer(&ssi->tx_wd); /* Stop boot handshake timer */
-	spin_unlock(&ssi->lock);
+	spin_unlock_bh(&ssi->lock);
 
 	dev_notice(&cl->device, "WAKELINES TEST %s\n",
 				wkres & SSIP_WAKETEST_FAILED ? "FAILED" : "OK");
@@ -741,20 +751,20 @@ static void ssip_rx_ready(struct hsi_client *cl)
 {
 	struct ssi_protocol *ssi = hsi_client_drvdata(cl);
 
-	spin_lock(&ssi->lock);
+	spin_lock_bh(&ssi->lock);
 	if (unlikely(ssi->main_state != ACTIVE)) {
 		dev_dbg(&cl->device, "READY on wrong state: S(%d) M(%d)\n",
 					ssi->send_state, ssi->main_state);
-		spin_unlock(&ssi->lock);
+		spin_unlock_bh(&ssi->lock);
 		return;
 	}
 	if (ssi->send_state != WAIT4READY) {
 		dev_dbg(&cl->device, "Ignore spurious READY command\n");
-		spin_unlock(&ssi->lock);
+		spin_unlock_bh(&ssi->lock);
 		return;
 	}
 	ssip_set_txstate(ssi, SEND_READY);
-	spin_unlock(&ssi->lock);
+	spin_unlock_bh(&ssi->lock);
 	ssip_xmit(cl);
 }
 
@@ -766,22 +776,22 @@ static void ssip_rx_strans(struct hsi_client *cl, u32 cmd)
 	int len = SSIP_PDU_LENGTH(cmd);
 
 	dev_dbg(&cl->device, "RX strans: %d frames\n", len);
-	spin_lock(&ssi->lock);
+	spin_lock_bh(&ssi->lock);
 	if (unlikely(ssi->main_state != ACTIVE)) {
 		dev_err(&cl->device, "START TRANS wrong state: S(%d) M(%d)\n",
 					ssi->send_state, ssi->main_state);
-		spin_unlock(&ssi->lock);
+		spin_unlock_bh(&ssi->lock);
 		return;
 	}
 	ssip_set_rxstate(ssi, RECEIVING);
 	if (unlikely(SSIP_MSG_ID(cmd) != ssi->rxid)) {
 		dev_err(&cl->device, "START TRANS id %d expected %d\n",
 					SSIP_MSG_ID(cmd), ssi->rxid);
-		spin_unlock(&ssi->lock);
+		spin_unlock_bh(&ssi->lock);
 		goto out1;
 	}
 	ssi->rxid++;
-	spin_unlock(&ssi->lock);
+	spin_unlock_bh(&ssi->lock);
 	skb = netdev_alloc_skb(ssi->netdev, len * 4);
 	if (unlikely(!skb)) {
 		dev_err(&cl->device, "No memory for rx skb\n");
@@ -849,7 +859,7 @@ static void ssip_swbreak_complete(struct hsi_msg *msg)
 	struct ssi_protocol *ssi = hsi_client_drvdata(cl);
 
 	ssip_release_cmd(msg);
-	spin_lock(&ssi->lock);
+	spin_lock_bh(&ssi->lock);
 	if (list_empty(&ssi->txqueue)) {
 		if (atomic_read(&ssi->tx_usecnt)) {
 			ssip_set_txstate(ssi, SEND_READY);
@@ -857,9 +867,9 @@ static void ssip_swbreak_complete(struct hsi_msg *msg)
 			ssip_set_txstate(ssi, SEND_IDLE);
 			hsi_stop_tx(cl);
 		}
-		spin_unlock(&ssi->lock);
+		spin_unlock_bh(&ssi->lock);
 	} else {
-		spin_unlock(&ssi->lock);
+		spin_unlock_bh(&ssi->lock);
 		ssip_xmit(cl);
 	}
 	netif_wake_queue(ssi->netdev);
@@ -876,17 +886,17 @@ static void ssip_tx_data_complete(struct hsi_msg *msg)
 		ssip_error(cl);
 		goto out;
 	}
-	spin_lock(&ssi->lock);
+	spin_lock_bh(&ssi->lock);
 	if (list_empty(&ssi->txqueue)) {
 		ssip_set_txstate(ssi, SENDING_SWBREAK);
-		spin_unlock(&ssi->lock);
+		spin_unlock_bh(&ssi->lock);
 		cmsg = ssip_claim_cmd(ssi);
 		ssip_set_cmd(cmsg, SSIP_SWBREAK_CMD);
 		cmsg->complete = ssip_swbreak_complete;
 		dev_dbg(&cl->device, "Send SWBREAK\n");
 		hsi_async_write(cl, cmsg);
 	} else {
-		spin_unlock(&ssi->lock);
+		spin_unlock_bh(&ssi->lock);
 		ssip_xmit(cl);
 	}
 out:
@@ -926,11 +936,11 @@ static int ssip_pn_open(struct net_device *dev)
 	}
 	dev_dbg(&cl->device, "Configuring SSI port\n");
 	hsi_setup(cl);
-	spin_lock_bh(&ssi->lock);
-	if (!ssi->waketest) {
-		ssi->waketest = 1;
+
+	if (!test_and_set_bit(SSIP_WAKETEST_FLAG, &ssi->flags))
 		ssi_waketest(cl, 1); /* FIXME: To be removed */
-	}
+
+	spin_lock_bh(&ssi->lock);
 	ssi->main_state = HANDSHAKE;
 	spin_unlock_bh(&ssi->lock);
 
@@ -959,6 +969,15 @@ static int ssip_pn_set_mtu(struct net_device *dev, int new_mtu)
 	return 0;
 }
 
+static void ssip_xmit_work(struct work_struct *work)
+{
+	struct ssi_protocol *ssi =
+				container_of(work, struct ssi_protocol, work);
+	struct hsi_client *cl = ssi->cl;
+
+	ssip_xmit(cl);
+}
+
 static int ssip_pn_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct hsi_client *cl = to_hsi_client(dev->dev.parent);
@@ -1011,7 +1030,7 @@ static int ssip_pn_xmit(struct sk_buff *skb, struct net_device *dev)
 		dev_dbg(&cl->device, "Start TX on SEND READY qlen %d\n",
 							ssi->txqueue_len);
 		spin_unlock_bh(&ssi->lock);
-		ssip_xmit(cl);
+		schedule_work(&ssi->work);
 	} else {
 		spin_unlock_bh(&ssi->lock);
 	}
@@ -1088,6 +1107,7 @@ static int ssi_protocol_probe(struct device *dev)
 	atomic_set(&ssi->tx_usecnt, 0);
 	hsi_client_set_drvdata(cl, ssi);
 	ssi->cl = cl;
+	INIT_WORK(&ssi->work, ssip_xmit_work);
 
 	ssi->channel_id_cmd = hsi_get_channel_id_by_name(cl, "mcsaab-control");
 	if (ssi->channel_id_cmd < 0) {
diff --git a/drivers/hsi/controllers/omap_ssi.h b/drivers/hsi/controllers/omap_ssi.h
index 7b4dec2c6..32ced0c8f 100644
--- a/drivers/hsi/controllers/omap_ssi.h
+++ b/drivers/hsi/controllers/omap_ssi.h
@@ -35,6 +35,8 @@
 #define SSI_MAX_GDD_LCH		8
 #define SSI_BYTES_TO_FRAMES(x) ((((x) - 1) >> 2) + 1)
 
+#define SSI_WAKE_EN 0
+
 /**
  * struct omap_ssm_ctx - OMAP synchronous serial module (TX/RX) context
  * @mode: Bit transmission mode
@@ -71,13 +73,14 @@ struct omap_ssm_ctx {
  * @txqueue: TX message queues
  * @rxqueue: RX message queues
  * @brkqueue: Queue of incoming HWBREAK requests (FRAME mode)
+ * @errqueue: Queue for failed messages
+ * @errqueue_work: Delayed Work for failed messages
  * @irq: IRQ number
  * @wake_irq: IRQ number for incoming wake line (-1 if none)
  * @wake_gpio: GPIO number for incoming wake line (-1 if none)
- * @pio_tasklet: Bottom half for PIO transfers and events
- * @wake_tasklet: Bottom half for incoming wake events
- * @wkin_cken: Keep track of clock references due to the incoming wake line
+ * @flags: flags to keep track of states
  * @wk_refcount: Reference count for output wake line
+ * @work: worker for starting TX
  * @sys_mpu_enable: Context for the interrupt enable register for irq 0
  * @sst: Context for the synchronous serial transmitter
  * @ssr: Context for the synchronous serial receiver
@@ -95,14 +98,15 @@ struct omap_ssi_port {
 	struct list_head	txqueue[SSI_MAX_CHANNELS];
 	struct list_head	rxqueue[SSI_MAX_CHANNELS];
 	struct list_head	brkqueue;
+	struct list_head	errqueue;
+	struct delayed_work	errqueue_work;
 	unsigned int		irq;
 	int			wake_irq;
 	struct gpio_desc	*wake_gpio;
-	struct tasklet_struct	pio_tasklet;
-	struct tasklet_struct	wake_tasklet;
 	bool			wktest:1; /* FIXME: HACK to be removed */
-	bool			wkin_cken:1; /* Workaround */
+	unsigned long		flags;
 	unsigned int		wk_refcount;
+	struct work_struct	work;
 	/* OMAP SSI port context */
 	u32			sys_mpu_enable; /* We use only one irq */
 	struct omap_ssm_ctx	sst;
@@ -138,7 +142,6 @@ struct gdd_trn {
  * @fck_rate: clock rate
  * @loss_count: To follow if we need to restore context or not
  * @max_speed: Maximum TX speed (Kb/s) set by the clients.
- * @sysconfig: SSI controller saved context
  * @gdd_gcr: SSI GDD saved context
  * @get_loss: Pointer to omap_pm_get_dev_context_loss_count, if any
  * @port: Array of pointers of the ports of the controller
@@ -158,7 +161,6 @@ struct omap_ssi_controller {
 	u32			loss_count;
 	u32			max_speed;
 	/* OMAP SSI Controller context */
-	u32			sysconfig;
 	u32			gdd_gcr;
 	int			(*get_loss)(struct device *dev);
 	struct omap_ssi_port	**port;
diff --git a/drivers/hsi/controllers/omap_ssi_core.c b/drivers/hsi/controllers/omap_ssi_core.c
index a3e0febfb..9a29b34ed 100644
--- a/drivers/hsi/controllers/omap_ssi_core.c
+++ b/drivers/hsi/controllers/omap_ssi_core.c
@@ -58,7 +58,7 @@ static int ssi_debug_show(struct seq_file *m, void *p __maybe_unused)
 	seq_printf(m, "REVISION\t: 0x%08x\n",  readl(sys + SSI_REVISION_REG));
 	seq_printf(m, "SYSCONFIG\t: 0x%08x\n", readl(sys + SSI_SYSCONFIG_REG));
 	seq_printf(m, "SYSSTATUS\t: 0x%08x\n", readl(sys + SSI_SYSSTATUS_REG));
-	pm_runtime_put_sync(ssi->device.parent);
+	pm_runtime_put(ssi->device.parent);
 
 	return 0;
 }
@@ -112,7 +112,7 @@ static int ssi_debug_gdd_show(struct seq_file *m, void *p __maybe_unused)
 				readw(gdd + SSI_GDD_CLNK_CTRL_REG(lch)));
 	}
 
-	pm_runtime_put_sync(ssi->device.parent);
+	pm_runtime_put(ssi->device.parent);
 
 	return 0;
 }
@@ -193,7 +193,7 @@ void ssi_waketest(struct hsi_client *cl, unsigned int enable)
 	} else {
 		writel_relaxed(SSI_WAKE(0),
 				omap_ssi->sys +	SSI_CLEAR_WAKE_REG(port->num));
-		pm_runtime_put_sync(ssi->device.parent);
+		pm_runtime_put(ssi->device.parent);
 	}
 }
 EXPORT_SYMBOL_GPL(ssi_waketest);
@@ -217,7 +217,7 @@ static void ssi_gdd_complete(struct hsi_controller *ssi, unsigned int lch)
 	if (msg->ttype == HSI_MSG_READ) {
 		dir = DMA_FROM_DEVICE;
 		val = SSI_DATAAVAILABLE(msg->channel);
-		pm_runtime_put_sync(ssi->device.parent);
+		pm_runtime_put(omap_port->pdev);
 	} else {
 		dir = DMA_TO_DEVICE;
 		val = SSI_DATAACCEPT(msg->channel);
@@ -235,7 +235,9 @@ static void ssi_gdd_complete(struct hsi_controller *ssi, unsigned int lch)
 		spin_lock(&omap_port->lock);
 		list_del(&msg->link); /* Dequeue msg */
 		spin_unlock(&omap_port->lock);
-		msg->complete(msg);
+
+		list_add_tail(&msg->link, &omap_port->errqueue);
+		schedule_delayed_work(&omap_port->errqueue_work, 0);
 		return;
 	}
 	spin_lock(&omap_port->lock);
@@ -255,7 +257,13 @@ static void ssi_gdd_tasklet(unsigned long dev)
 	unsigned int lch;
 	u32 status_reg;
 
-	pm_runtime_get_sync(ssi->device.parent);
+	pm_runtime_get(ssi->device.parent);
+
+	if (!pm_runtime_active(ssi->device.parent)) {
+		dev_warn(ssi->device.parent, "ssi_gdd_tasklet called without runtime PM!\n");
+		pm_runtime_put(ssi->device.parent);
+		return;
+	}
 
 	status_reg = readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG);
 	for (lch = 0; lch < SSI_MAX_GDD_LCH; lch++) {
@@ -265,7 +273,7 @@ static void ssi_gdd_tasklet(unsigned long dev)
 	writel_relaxed(status_reg, sys + SSI_GDD_MPU_IRQ_STATUS_REG);
 	status_reg = readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG);
 
-	pm_runtime_put_sync(ssi->device.parent);
+	pm_runtime_put(ssi->device.parent);
 
 	if (status_reg)
 		tasklet_hi_schedule(&omap_ssi->gdd_tasklet);
@@ -312,7 +320,7 @@ static int ssi_clk_event(struct notifier_block *nb, unsigned long event,
 				continue;
 
 			/* Workaround for SWBREAK + CAwake down race in CMT */
-			tasklet_disable(&omap_port->wake_tasklet);
+			disable_irq(omap_port->wake_irq);
 
 			/* stop all ssi communication */
 			pinctrl_pm_select_idle_state(omap_port->pdev);
@@ -338,7 +346,7 @@ static int ssi_clk_event(struct notifier_block *nb, unsigned long event,
 
 			/* resume ssi communication */
 			pinctrl_pm_select_default_state(omap_port->pdev);
-			tasklet_enable(&omap_port->wake_tasklet);
+			enable_irq(omap_port->wake_irq);
 		}
 
 		break;
@@ -452,8 +460,6 @@ out_err:
 static int ssi_hw_init(struct hsi_controller *ssi)
 {
 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
-	unsigned int i;
-	u32 val;
 	int err;
 
 	err = pm_runtime_get_sync(ssi->device.parent);
@@ -461,27 +467,12 @@ static int ssi_hw_init(struct hsi_controller *ssi)
 		dev_err(&ssi->device, "runtime PM failed %d\n", err);
 		return err;
 	}
-	/* Reseting SSI controller */
-	writel_relaxed(SSI_SOFTRESET, omap_ssi->sys + SSI_SYSCONFIG_REG);
-	val = readl(omap_ssi->sys + SSI_SYSSTATUS_REG);
-	for (i = 0; ((i < 20) && !(val & SSI_RESETDONE)); i++) {
-		msleep(20);
-		val = readl(omap_ssi->sys + SSI_SYSSTATUS_REG);
-	}
-	if (!(val & SSI_RESETDONE)) {
-		dev_err(&ssi->device, "SSI HW reset failed\n");
-		pm_runtime_put_sync(ssi->device.parent);
-		return -EIO;
-	}
 	/* Reseting GDD */
 	writel_relaxed(SSI_SWRESET, omap_ssi->gdd + SSI_GDD_GRST_REG);
 	/* Get FCK rate in KHz */
 	omap_ssi->fck_rate = DIV_ROUND_CLOSEST(ssi_get_clk_rate(ssi), 1000);
 	dev_dbg(&ssi->device, "SSI fck rate %lu KHz\n", omap_ssi->fck_rate);
-	/* Set default PM settings */
-	val = SSI_AUTOIDLE | SSI_SIDLEMODE_SMART | SSI_MIDLEMODE_SMART;
-	writel_relaxed(val, omap_ssi->sys + SSI_SYSCONFIG_REG);
-	omap_ssi->sysconfig = val;
+
 	writel_relaxed(SSI_CLK_AUTOGATING_ON, omap_ssi->sys + SSI_GDD_GCR_REG);
 	omap_ssi->gdd_gcr = SSI_CLK_AUTOGATING_ON;
 	pm_runtime_put_sync(ssi->device.parent);
@@ -552,7 +543,6 @@ static int ssi_probe(struct platform_device *pd)
 	if (err < 0)
 		goto out1;
 
-	pm_runtime_irq_safe(&pd->dev);
 	pm_runtime_enable(&pd->dev);
 
 	err = ssi_hw_init(ssi);
diff --git a/drivers/hsi/controllers/omap_ssi_port.c b/drivers/hsi/controllers/omap_ssi_port.c
index 6b8f77397..7765de2f1 100644
--- a/drivers/hsi/controllers/omap_ssi_port.c
+++ b/drivers/hsi/controllers/omap_ssi_port.c
@@ -126,7 +126,7 @@ static int ssi_debug_port_show(struct seq_file *m, void *p __maybe_unused)
 		seq_printf(m, "BUFFER_CH%d\t: 0x%08x\n", ch,
 				readl(base + SSI_SSR_BUFFER_CH_REG(ch)));
 	}
-	pm_runtime_put_sync(omap_port->pdev);
+	pm_runtime_put_autosuspend(omap_port->pdev);
 
 	return 0;
 }
@@ -150,7 +150,7 @@ static int ssi_div_get(void *data, u64 *val)
 
 	pm_runtime_get_sync(omap_port->pdev);
 	*val = readl(omap_port->sst_base + SSI_SST_DIVISOR_REG);
-	pm_runtime_put_sync(omap_port->pdev);
+	pm_runtime_put_autosuspend(omap_port->pdev);
 
 	return 0;
 }
@@ -166,7 +166,7 @@ static int ssi_div_set(void *data, u64 val)
 	pm_runtime_get_sync(omap_port->pdev);
 	writel(val, omap_port->sst_base + SSI_SST_DIVISOR_REG);
 	omap_port->sst.divisor = val;
-	pm_runtime_put_sync(omap_port->pdev);
+	pm_runtime_put_autosuspend(omap_port->pdev);
 
 	return 0;
 }
@@ -193,6 +193,21 @@ static int ssi_debug_add_port(struct omap_ssi_port *omap_port,
 }
 #endif
 
+static void ssi_process_errqueue(struct work_struct *work)
+{
+	struct omap_ssi_port *omap_port;
+	struct list_head *head, *tmp;
+	struct hsi_msg *msg;
+
+	omap_port = container_of(work, struct omap_ssi_port, errqueue_work.work);
+
+	list_for_each_safe(head, tmp, &omap_port->errqueue) {
+		msg = list_entry(head, struct hsi_msg, link);
+		msg->complete(msg);
+		list_del(head);
+	}
+}
+
 static int ssi_claim_lch(struct hsi_msg *msg)
 {
 
@@ -225,11 +240,21 @@ static int ssi_start_dma(struct hsi_msg *msg, int lch)
 	u32 d_addr;
 	u32 tmp;
 
+	/* Hold clocks during the transfer */
+	pm_runtime_get(omap_port->pdev);
+
+	if (!pm_runtime_active(omap_port->pdev)) {
+		dev_warn(&port->device, "ssi_start_dma called without runtime PM!\n");
+		pm_runtime_put_autosuspend(omap_port->pdev);
+		return -EREMOTEIO;
+	}
+
 	if (msg->ttype == HSI_MSG_READ) {
 		err = dma_map_sg(&ssi->device, msg->sgt.sgl, msg->sgt.nents,
 							DMA_FROM_DEVICE);
 		if (err < 0) {
 			dev_dbg(&ssi->device, "DMA map SG failed !\n");
+			pm_runtime_put_autosuspend(omap_port->pdev);
 			return err;
 		}
 		csdp = SSI_DST_BURST_4x32_BIT | SSI_DST_MEMORY_PORT |
@@ -246,6 +271,7 @@ static int ssi_start_dma(struct hsi_msg *msg, int lch)
 							DMA_TO_DEVICE);
 		if (err < 0) {
 			dev_dbg(&ssi->device, "DMA map SG failed !\n");
+			pm_runtime_put_autosuspend(omap_port->pdev);
 			return err;
 		}
 		csdp = SSI_SRC_BURST_4x32_BIT | SSI_SRC_MEMORY_PORT |
@@ -261,9 +287,6 @@ static int ssi_start_dma(struct hsi_msg *msg, int lch)
 	dev_dbg(&ssi->device, "lch %d cdsp %08x ccr %04x s_addr %08x d_addr %08x\n",
 		lch, csdp, ccr, s_addr, d_addr);
 
-	/* Hold clocks during the transfer */
-	pm_runtime_get_sync(omap_port->pdev);
-
 	writew_relaxed(csdp, gdd + SSI_GDD_CSDP_REG(lch));
 	writew_relaxed(SSI_BLOCK_IE | SSI_TOUT_IE, gdd + SSI_GDD_CICR_REG(lch));
 	writel_relaxed(d_addr, gdd + SSI_GDD_CDSA_REG(lch));
@@ -290,11 +313,18 @@ static int ssi_start_pio(struct hsi_msg *msg)
 	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 	u32 val;
 
-	pm_runtime_get_sync(omap_port->pdev);
+	pm_runtime_get(omap_port->pdev);
+
+	if (!pm_runtime_active(omap_port->pdev)) {
+		dev_warn(&port->device, "ssi_start_pio called without runtime PM!\n");
+		pm_runtime_put_autosuspend(omap_port->pdev);
+		return -EREMOTEIO;
+	}
+
 	if (msg->ttype == HSI_MSG_WRITE) {
 		val = SSI_DATAACCEPT(msg->channel);
 		/* Hold clocks for pio writes */
-		pm_runtime_get_sync(omap_port->pdev);
+		pm_runtime_get(omap_port->pdev);
 	} else {
 		val = SSI_DATAAVAILABLE(msg->channel) | SSI_ERROROCCURED;
 	}
@@ -302,7 +332,7 @@ static int ssi_start_pio(struct hsi_msg *msg)
 						msg->ttype ? "write" : "read");
 	val |= readl(omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
 	writel(val, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
-	pm_runtime_put_sync(omap_port->pdev);
+	pm_runtime_put_autosuspend(omap_port->pdev);
 	msg->actual_len = 0;
 	msg->status = HSI_STATUS_PROCEEDING;
 
@@ -360,7 +390,8 @@ static int ssi_async_break(struct hsi_msg *msg)
 		spin_unlock_bh(&omap_port->lock);
 	}
 out:
-	pm_runtime_put_sync(omap_port->pdev);
+	pm_runtime_mark_last_busy(omap_port->pdev);
+	pm_runtime_put_autosuspend(omap_port->pdev);
 
 	return err;
 }
@@ -388,6 +419,8 @@ static int ssi_async(struct hsi_msg *msg)
 		queue = &omap_port->rxqueue[msg->channel];
 	}
 	msg->status = HSI_STATUS_QUEUED;
+
+	pm_runtime_get_sync(omap_port->pdev);
 	spin_lock_bh(&omap_port->lock);
 	list_add_tail(&msg->link, queue);
 	err = ssi_start_transfer(queue);
@@ -396,6 +429,8 @@ static int ssi_async(struct hsi_msg *msg)
 		msg->status = HSI_STATUS_ERROR;
 	}
 	spin_unlock_bh(&omap_port->lock);
+	pm_runtime_mark_last_busy(omap_port->pdev);
+	pm_runtime_put_autosuspend(omap_port->pdev);
 	dev_dbg(&port->device, "msg status %d ttype %d ch %d\n",
 				msg->status, msg->ttype, msg->channel);
 
@@ -497,7 +532,8 @@ static int ssi_setup(struct hsi_client *cl)
 	omap_port->ssr.mode = cl->rx_cfg.mode;
 out:
 	spin_unlock_bh(&omap_port->lock);
-	pm_runtime_put_sync(omap_port->pdev);
+	pm_runtime_mark_last_busy(omap_port->pdev);
+	pm_runtime_put_autosuspend(omap_port->pdev);
 
 	return err;
 }
@@ -528,7 +564,7 @@ static int ssi_flush(struct hsi_client *cl)
 			continue;
 		writew_relaxed(0, omap_ssi->gdd + SSI_GDD_CCR_REG(i));
 		if (msg->ttype == HSI_MSG_READ)
-			pm_runtime_put_sync(omap_port->pdev);
+			pm_runtime_put_autosuspend(omap_port->pdev);
 		omap_ssi->gdd_trn[i].msg = NULL;
 	}
 	/* Flush all SST buffers */
@@ -552,7 +588,7 @@ static int ssi_flush(struct hsi_client *cl)
 	for (i = 0; i < omap_port->channels; i++) {
 		/* Release write clocks */
 		if (!list_empty(&omap_port->txqueue[i]))
-			pm_runtime_put_sync(omap_port->pdev);
+			pm_runtime_put_autosuspend(omap_port->pdev);
 		ssi_flush_queue(&omap_port->txqueue[i], NULL);
 		ssi_flush_queue(&omap_port->rxqueue[i], NULL);
 	}
@@ -562,17 +598,28 @@ static int ssi_flush(struct hsi_client *cl)
 	pinctrl_pm_select_default_state(omap_port->pdev);
 
 	spin_unlock_bh(&omap_port->lock);
-	pm_runtime_put_sync(omap_port->pdev);
+	pm_runtime_mark_last_busy(omap_port->pdev);
+	pm_runtime_put_autosuspend(omap_port->pdev);
 
 	return 0;
 }
 
+static void start_tx_work(struct work_struct *work)
+{
+	struct omap_ssi_port *omap_port =
+				container_of(work, struct omap_ssi_port, work);
+	struct hsi_port *port = to_hsi_port(omap_port->dev);
+	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
+	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
+
+	pm_runtime_get_sync(omap_port->pdev); /* Grab clocks */
+	writel(SSI_WAKE(0), omap_ssi->sys + SSI_SET_WAKE_REG(port->num));
+}
+
 static int ssi_start_tx(struct hsi_client *cl)
 {
 	struct hsi_port *port = hsi_get_port(cl);
 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
-	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
-	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
 
 	dev_dbg(&port->device, "Wake out high %d\n", omap_port->wk_refcount);
 
@@ -581,10 +628,10 @@ static int ssi_start_tx(struct hsi_client *cl)
 		spin_unlock_bh(&omap_port->wk_lock);
 		return 0;
 	}
-	pm_runtime_get_sync(omap_port->pdev); /* Grab clocks */
-	writel(SSI_WAKE(0), omap_ssi->sys + SSI_SET_WAKE_REG(port->num));
 	spin_unlock_bh(&omap_port->wk_lock);
 
+	schedule_work(&omap_port->work);
+
 	return 0;
 }
 
@@ -604,9 +651,12 @@ static int ssi_stop_tx(struct hsi_client *cl)
 		return 0;
 	}
 	writel(SSI_WAKE(0), omap_ssi->sys + SSI_CLEAR_WAKE_REG(port->num));
-	pm_runtime_put_sync(omap_port->pdev); /* Release clocks */
 	spin_unlock_bh(&omap_port->wk_lock);
 
+	pm_runtime_mark_last_busy(omap_port->pdev);
+	pm_runtime_put_autosuspend(omap_port->pdev); /* Release clocks */
+
+
 	return 0;
 }
 
@@ -616,6 +666,7 @@ static void ssi_transfer(struct omap_ssi_port *omap_port,
 	struct hsi_msg *msg;
 	int err = -1;
 
+	pm_runtime_get(omap_port->pdev);
 	spin_lock_bh(&omap_port->lock);
 	while (err < 0) {
 		err = ssi_start_transfer(queue);
@@ -630,6 +681,8 @@ static void ssi_transfer(struct omap_ssi_port *omap_port,
 		}
 	}
 	spin_unlock_bh(&omap_port->lock);
+	pm_runtime_mark_last_busy(omap_port->pdev);
+	pm_runtime_put_autosuspend(omap_port->pdev);
 }
 
 static void ssi_cleanup_queues(struct hsi_client *cl)
@@ -658,7 +711,8 @@ static void ssi_cleanup_queues(struct hsi_client *cl)
 			txbufstate |= (1 << i);
 			status |= SSI_DATAACCEPT(i);
 			/* Release the clocks writes, also GDD ones */
-			pm_runtime_put_sync(omap_port->pdev);
+			pm_runtime_mark_last_busy(omap_port->pdev);
+			pm_runtime_put_autosuspend(omap_port->pdev);
 		}
 		ssi_flush_queue(&omap_port->txqueue[i], cl);
 	}
@@ -712,8 +766,10 @@ static void ssi_cleanup_gdd(struct hsi_controller *ssi, struct hsi_client *cl)
 		 * Clock references for write will be handled in
 		 * ssi_cleanup_queues
 		 */
-		if (msg->ttype == HSI_MSG_READ)
-			pm_runtime_put_sync(omap_port->pdev);
+		if (msg->ttype == HSI_MSG_READ) {
+			pm_runtime_mark_last_busy(omap_port->pdev);
+			pm_runtime_put_autosuspend(omap_port->pdev);
+		}
 		omap_ssi->gdd_trn[i].msg = NULL;
 	}
 	tmp = readl_relaxed(omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
@@ -738,32 +794,30 @@ static int ssi_release(struct hsi_client *cl)
 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
 
-	spin_lock_bh(&omap_port->lock);
 	pm_runtime_get_sync(omap_port->pdev);
+	spin_lock_bh(&omap_port->lock);
 	/* Stop all the pending DMA requests for that client */
 	ssi_cleanup_gdd(ssi, cl);
 	/* Now cleanup all the queues */
 	ssi_cleanup_queues(cl);
-	pm_runtime_put_sync(omap_port->pdev);
 	/* If it is the last client of the port, do extra checks and cleanup */
 	if (port->claimed <= 1) {
 		/*
 		 * Drop the clock reference for the incoming wake line
 		 * if it is still kept high by the other side.
 		 */
-		if (omap_port->wkin_cken) {
+		if (test_and_clear_bit(SSI_WAKE_EN, &omap_port->flags))
 			pm_runtime_put_sync(omap_port->pdev);
-			omap_port->wkin_cken = 0;
-		}
-		pm_runtime_get_sync(omap_port->pdev);
+		pm_runtime_get(omap_port->pdev);
 		/* Stop any SSI TX/RX without a client */
 		ssi_set_port_mode(omap_port, SSI_MODE_SLEEP);
 		omap_port->sst.mode = SSI_MODE_SLEEP;
 		omap_port->ssr.mode = SSI_MODE_SLEEP;
-		pm_runtime_put_sync(omap_port->pdev);
+		pm_runtime_put(omap_port->pdev);
 		WARN_ON(omap_port->wk_refcount != 0);
 	}
 	spin_unlock_bh(&omap_port->lock);
+	pm_runtime_put_sync(omap_port->pdev);
 
 	return 0;
 }
@@ -868,7 +922,7 @@ static void ssi_pio_complete(struct hsi_port *port, struct list_head *queue)
 	u32 reg;
 	u32 val;
 
-	spin_lock(&omap_port->lock);
+	spin_lock_bh(&omap_port->lock);
 	msg = list_first_entry(queue, struct hsi_msg, link);
 	if ((!msg->sgt.nents) || (!msg->sgt.sgl->length)) {
 		msg->actual_len = 0;
@@ -900,7 +954,7 @@ static void ssi_pio_complete(struct hsi_port *port, struct list_head *queue)
 					(msg->ttype == HSI_MSG_WRITE))) {
 			writel(val, omap_ssi->sys +
 					SSI_MPU_STATUS_REG(port->num, 0));
-			spin_unlock(&omap_port->lock);
+			spin_unlock_bh(&omap_port->lock);
 
 			return;
 		}
@@ -910,18 +964,19 @@ static void ssi_pio_complete(struct hsi_port *port, struct list_head *queue)
 	reg = readl(omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
 	if (msg->ttype == HSI_MSG_WRITE) {
 		/* Release clocks for write transfer */
-		pm_runtime_put_sync(omap_port->pdev);
+		pm_runtime_mark_last_busy(omap_port->pdev);
+		pm_runtime_put_autosuspend(omap_port->pdev);
 	}
 	reg &= ~val;
 	writel_relaxed(reg, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
 	writel_relaxed(val, omap_ssi->sys + SSI_MPU_STATUS_REG(port->num, 0));
 	list_del(&msg->link);
-	spin_unlock(&omap_port->lock);
+	spin_unlock_bh(&omap_port->lock);
 	msg->complete(msg);
 	ssi_transfer(omap_port, queue);
 }
 
-static void ssi_pio_tasklet(unsigned long ssi_port)
+static irqreturn_t ssi_pio_thread(int irq, void *ssi_port)
 {
 	struct hsi_port *port = (struct hsi_port *)ssi_port;
 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
@@ -932,41 +987,35 @@ static void ssi_pio_tasklet(unsigned long ssi_port)
 	u32 status_reg;
 
 	pm_runtime_get_sync(omap_port->pdev);
-	status_reg = readl(sys + SSI_MPU_STATUS_REG(port->num, 0));
-	status_reg &= readl(sys + SSI_MPU_ENABLE_REG(port->num, 0));
 
-	for (ch = 0; ch < omap_port->channels; ch++) {
-		if (status_reg & SSI_DATAACCEPT(ch))
-			ssi_pio_complete(port, &omap_port->txqueue[ch]);
-		if (status_reg & SSI_DATAAVAILABLE(ch))
-			ssi_pio_complete(port, &omap_port->rxqueue[ch]);
-	}
-	if (status_reg & SSI_BREAKDETECTED)
-		ssi_break_complete(port);
-	if (status_reg & SSI_ERROROCCURED)
-		ssi_error(port);
+	do {
+		status_reg = readl(sys + SSI_MPU_STATUS_REG(port->num, 0));
+		status_reg &= readl(sys + SSI_MPU_ENABLE_REG(port->num, 0));
 
-	status_reg = readl(sys + SSI_MPU_STATUS_REG(port->num, 0));
-	status_reg &= readl(sys + SSI_MPU_ENABLE_REG(port->num, 0));
-	pm_runtime_put_sync(omap_port->pdev);
+		for (ch = 0; ch < omap_port->channels; ch++) {
+			if (status_reg & SSI_DATAACCEPT(ch))
+				ssi_pio_complete(port, &omap_port->txqueue[ch]);
+			if (status_reg & SSI_DATAAVAILABLE(ch))
+				ssi_pio_complete(port, &omap_port->rxqueue[ch]);
+		}
+		if (status_reg & SSI_BREAKDETECTED)
+			ssi_break_complete(port);
+		if (status_reg & SSI_ERROROCCURED)
+			ssi_error(port);
 
-	if (status_reg)
-		tasklet_hi_schedule(&omap_port->pio_tasklet);
-	else
-		enable_irq(omap_port->irq);
-}
+		status_reg = readl(sys + SSI_MPU_STATUS_REG(port->num, 0));
+		status_reg &= readl(sys + SSI_MPU_ENABLE_REG(port->num, 0));
 
-static irqreturn_t ssi_pio_isr(int irq, void *port)
-{
-	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
+		/* TODO: sleep if we retry? */
+	} while (status_reg);
 
-	tasklet_hi_schedule(&omap_port->pio_tasklet);
-	disable_irq_nosync(irq);
+	pm_runtime_mark_last_busy(omap_port->pdev);
+	pm_runtime_put_autosuspend(omap_port->pdev);
 
 	return IRQ_HANDLED;
 }
 
-static void ssi_wake_tasklet(unsigned long ssi_port)
+static irqreturn_t ssi_wake_thread(int irq __maybe_unused, void *ssi_port)
 {
 	struct hsi_port *port = (struct hsi_port *)ssi_port;
 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
@@ -981,12 +1030,8 @@ static void ssi_wake_tasklet(unsigned long ssi_port)
 		 * This workaround will avoid breaking the clock reference
 		 * count when such a situation ocurrs.
 		 */
-		spin_lock(&omap_port->lock);
-		if (!omap_port->wkin_cken) {
-			omap_port->wkin_cken = 1;
+		if (!test_and_set_bit(SSI_WAKE_EN, &omap_port->flags))
 			pm_runtime_get_sync(omap_port->pdev);
-		}
-		spin_unlock(&omap_port->lock);
 		dev_dbg(&ssi->device, "Wake in high\n");
 		if (omap_port->wktest) { /* FIXME: HACK ! To be removed */
 			writel(SSI_WAKE(0),
@@ -1000,26 +1045,16 @@ static void ssi_wake_tasklet(unsigned long ssi_port)
 				omap_ssi->sys + SSI_CLEAR_WAKE_REG(port->num));
 		}
 		hsi_event(port, HSI_EVENT_STOP_RX);
-		spin_lock(&omap_port->lock);
-		if (omap_port->wkin_cken) {
-			pm_runtime_put_sync(omap_port->pdev);
-			omap_port->wkin_cken = 0;
+		if (test_and_clear_bit(SSI_WAKE_EN, &omap_port->flags)) {
+			pm_runtime_mark_last_busy(omap_port->pdev);
+			pm_runtime_put_autosuspend(omap_port->pdev);
 		}
-		spin_unlock(&omap_port->lock);
 	}
-}
-
-static irqreturn_t ssi_wake_isr(int irq __maybe_unused, void *ssi_port)
-{
-	struct omap_ssi_port *omap_port = hsi_port_drvdata(ssi_port);
-
-	tasklet_hi_schedule(&omap_port->wake_tasklet);
 
 	return IRQ_HANDLED;
 }
 
-static int ssi_port_irq(struct hsi_port *port,
-						struct platform_device *pd)
+static int ssi_port_irq(struct hsi_port *port, struct platform_device *pd)
 {
 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
 	int err;
@@ -1030,18 +1065,15 @@ static int ssi_port_irq(struct hsi_port *port,
 		return err;
 	}
 	omap_port->irq = err;
-	tasklet_init(&omap_port->pio_tasklet, ssi_pio_tasklet,
-							(unsigned long)port);
-	err = devm_request_irq(&port->device, omap_port->irq, ssi_pio_isr,
-						0, "mpu_irq0", port);
+	err = devm_request_threaded_irq(&port->device, omap_port->irq, NULL,
+				ssi_pio_thread, IRQF_ONESHOT, "SSI PORT", port);
 	if (err < 0)
 		dev_err(&port->device, "Request IRQ %d failed (%d)\n",
 							omap_port->irq, err);
 	return err;
 }
 
-static int ssi_wake_irq(struct hsi_port *port,
-						struct platform_device *pd)
+static int ssi_wake_irq(struct hsi_port *port, struct platform_device *pd)
 {
 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
 	int cawake_irq;
@@ -1053,13 +1085,12 @@ static int ssi_wake_irq(struct hsi_port *port,
 	}
 
 	cawake_irq = gpiod_to_irq(omap_port->wake_gpio);
-
 	omap_port->wake_irq = cawake_irq;
-	tasklet_init(&omap_port->wake_tasklet, ssi_wake_tasklet,
-							(unsigned long)port);
-	err = devm_request_irq(&port->device, cawake_irq, ssi_wake_isr,
-		IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
-							"cawake", port);
+
+	err = devm_request_threaded_irq(&port->device, cawake_irq, NULL,
+		ssi_wake_thread,
+		IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+		"SSI cawake", port);
 	if (err < 0)
 		dev_err(&port->device, "Request Wake in IRQ %d failed %d\n",
 						cawake_irq, err);
@@ -1169,6 +1200,9 @@ static int ssi_port_probe(struct platform_device *pd)
 	omap_port->pdev = &pd->dev;
 	omap_port->port_id = port_id;
 
+	INIT_DEFERRABLE_WORK(&omap_port->errqueue_work, ssi_process_errqueue);
+	INIT_WORK(&omap_port->work, start_tx_work);
+
 	/* initialize HSI port */
 	port->async	= ssi_async;
 	port->setup	= ssi_setup;
@@ -1202,7 +1236,8 @@ static int ssi_port_probe(struct platform_device *pd)
 	spin_lock_init(&omap_port->wk_lock);
 	omap_port->dev = &port->device;
 
-	pm_runtime_irq_safe(omap_port->pdev);
+	pm_runtime_use_autosuspend(omap_port->pdev);
+	pm_runtime_set_autosuspend_delay(omap_port->pdev, 250);
 	pm_runtime_enable(omap_port->pdev);
 
 #ifdef CONFIG_DEBUG_FS
@@ -1234,10 +1269,9 @@ static int ssi_port_remove(struct platform_device *pd)
 	ssi_debug_remove_port(port);
 #endif
 
-	hsi_port_unregister_clients(port);
+	cancel_delayed_work_sync(&omap_port->errqueue_work);
 
-	tasklet_kill(&omap_port->wake_tasklet);
-	tasklet_kill(&omap_port->pio_tasklet);
+	hsi_port_unregister_clients(port);
 
 	port->async	= hsi_dummy_msg;
 	port->setup	= hsi_dummy_cl;
@@ -1248,6 +1282,8 @@ static int ssi_port_remove(struct platform_device *pd)
 
 	omap_ssi->port[omap_port->port_id] = NULL;
 	platform_set_drvdata(pd, NULL);
+
+	pm_runtime_dont_use_autosuspend(&pd->dev);
 	pm_runtime_disable(&pd->dev);
 
 	return 0;
diff --git a/drivers/hsi/hsi_core.c b/drivers/hsi/hsi_core.c
new file mode 100644
index 000000000..c2a2a9795
--- /dev/null
+++ b/drivers/hsi/hsi_core.c
@@ -0,0 +1,781 @@
+/*
+ * HSI core.
+ *
+ * Copyright (C) 2010 Nokia Corporation. All rights reserved.
+ *
+ * Contact: Carlos Chinea <carlos.chinea@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+#include <linux/hsi/hsi.h>
+#include <linux/compiler.h>
+#include <linux/list.h>
+#include <linux/kobject.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include "hsi_core.h"
+
+static ssize_t modalias_show(struct device *dev,
+			struct device_attribute *a __maybe_unused, char *buf)
+{
+	return sprintf(buf, "hsi:%s\n", dev_name(dev));
+}
+static DEVICE_ATTR_RO(modalias);
+
+static struct attribute *hsi_bus_dev_attrs[] = {
+	&dev_attr_modalias.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(hsi_bus_dev);
+
+static int hsi_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	add_uevent_var(env, "MODALIAS=hsi:%s", dev_name(dev));
+
+	return 0;
+}
+
+static int hsi_bus_match(struct device *dev, struct device_driver *driver)
+{
+	if (of_driver_match_device(dev, driver))
+		return true;
+
+	if (strcmp(dev_name(dev), driver->name) == 0)
+		return true;
+
+	return false;
+}
+
+static struct bus_type hsi_bus_type = {
+	.name		= "hsi",
+	.dev_groups	= hsi_bus_dev_groups,
+	.match		= hsi_bus_match,
+	.uevent		= hsi_bus_uevent,
+};
+
+static void hsi_client_release(struct device *dev)
+{
+	struct hsi_client *cl = to_hsi_client(dev);
+
+	kfree(cl->tx_cfg.channels);
+	kfree(cl->rx_cfg.channels);
+	kfree(cl);
+}
+
+struct hsi_client *hsi_new_client(struct hsi_port *port,
+						struct hsi_board_info *info)
+{
+	struct hsi_client *cl;
+	size_t size;
+
+	cl = kzalloc(sizeof(*cl), GFP_KERNEL);
+	if (!cl)
+		goto err;
+
+	cl->tx_cfg = info->tx_cfg;
+	if (cl->tx_cfg.channels) {
+		size = cl->tx_cfg.num_channels * sizeof(*cl->tx_cfg.channels);
+		cl->tx_cfg.channels = kmemdup(info->tx_cfg.channels, size,
+					      GFP_KERNEL);
+		if (!cl->tx_cfg.channels)
+			goto err_tx;
+	}
+
+	cl->rx_cfg = info->rx_cfg;
+	if (cl->rx_cfg.channels) {
+		size = cl->rx_cfg.num_channels * sizeof(*cl->rx_cfg.channels);
+		cl->rx_cfg.channels = kmemdup(info->rx_cfg.channels, size,
+					      GFP_KERNEL);
+		if (!cl->rx_cfg.channels)
+			goto err_rx;
+	}
+
+	cl->device.bus = &hsi_bus_type;
+	cl->device.parent = &port->device;
+	cl->device.release = hsi_client_release;
+	dev_set_name(&cl->device, "%s", info->name);
+	cl->device.platform_data = info->platform_data;
+	if (info->archdata)
+		cl->device.archdata = *info->archdata;
+	if (device_register(&cl->device) < 0) {
+		pr_err("hsi: failed to register client: %s\n", info->name);
+		put_device(&cl->device);
+	}
+
+	return cl;
+err_rx:
+	kfree(cl->tx_cfg.channels);
+err_tx:
+	kfree(cl);
+err:
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(hsi_new_client);
+
+static void hsi_scan_board_info(struct hsi_controller *hsi)
+{
+	struct hsi_cl_info *cl_info;
+	struct hsi_port	*p;
+
+	list_for_each_entry(cl_info, &hsi_board_list, list)
+		if (cl_info->info.hsi_id == hsi->id) {
+			p = hsi_find_port_num(hsi, cl_info->info.port);
+			if (!p)
+				continue;
+			hsi_new_client(p, &cl_info->info);
+		}
+}
+
+#ifdef CONFIG_OF
+static struct hsi_board_info hsi_char_dev_info = {
+	.name = "hsi_char",
+};
+
+static int hsi_of_property_parse_mode(struct device_node *client, char *name,
+				      unsigned int *result)
+{
+	const char *mode;
+	int err;
+
+	err = of_property_read_string(client, name, &mode);
+	if (err < 0)
+		return err;
+
+	if (strcmp(mode, "stream") == 0)
+		*result = HSI_MODE_STREAM;
+	else if (strcmp(mode, "frame") == 0)
+		*result = HSI_MODE_FRAME;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+static int hsi_of_property_parse_flow(struct device_node *client, char *name,
+				      unsigned int *result)
+{
+	const char *flow;
+	int err;
+
+	err = of_property_read_string(client, name, &flow);
+	if (err < 0)
+		return err;
+
+	if (strcmp(flow, "synchronized") == 0)
+		*result = HSI_FLOW_SYNC;
+	else if (strcmp(flow, "pipeline") == 0)
+		*result = HSI_FLOW_PIPE;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+static int hsi_of_property_parse_arb_mode(struct device_node *client,
+					  char *name, unsigned int *result)
+{
+	const char *arb_mode;
+	int err;
+
+	err = of_property_read_string(client, name, &arb_mode);
+	if (err < 0)
+		return err;
+
+	if (strcmp(arb_mode, "round-robin") == 0)
+		*result = HSI_ARB_RR;
+	else if (strcmp(arb_mode, "priority") == 0)
+		*result = HSI_ARB_PRIO;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+static void hsi_add_client_from_dt(struct hsi_port *port,
+						struct device_node *client)
+{
+	struct hsi_client *cl;
+	struct hsi_channel channel;
+	struct property *prop;
+	char name[32];
+	int length, cells, err, i, max_chan, mode;
+
+	cl = kzalloc(sizeof(*cl), GFP_KERNEL);
+	if (!cl)
+		return;
+
+	err = of_modalias_node(client, name, sizeof(name));
+	if (err)
+		goto err;
+
+	dev_set_name(&cl->device, "%s", name);
+
+	err = hsi_of_property_parse_mode(client, "hsi-mode", &mode);
+	if (err) {
+		err = hsi_of_property_parse_mode(client, "hsi-rx-mode",
+						 &cl->rx_cfg.mode);
+		if (err)
+			goto err;
+
+		err = hsi_of_property_parse_mode(client, "hsi-tx-mode",
+						 &cl->tx_cfg.mode);
+		if (err)
+			goto err;
+	} else {
+		cl->rx_cfg.mode = mode;
+		cl->tx_cfg.mode = mode;
+	}
+
+	err = of_property_read_u32(client, "hsi-speed-kbps",
+				   &cl->tx_cfg.speed);
+	if (err)
+		goto err;
+	cl->rx_cfg.speed = cl->tx_cfg.speed;
+
+	err = hsi_of_property_parse_flow(client, "hsi-flow",
+					 &cl->rx_cfg.flow);
+	if (err)
+		goto err;
+
+	err = hsi_of_property_parse_arb_mode(client, "hsi-arb-mode",
+					     &cl->rx_cfg.arb_mode);
+	if (err)
+		goto err;
+
+	prop = of_find_property(client, "hsi-channel-ids", &length);
+	if (!prop) {
+		err = -EINVAL;
+		goto err;
+	}
+
+	cells = length / sizeof(u32);
+
+	cl->rx_cfg.num_channels = cells;
+	cl->tx_cfg.num_channels = cells;
+
+	cl->rx_cfg.channels = kzalloc(cells * sizeof(channel), GFP_KERNEL);
+	if (!cl->rx_cfg.channels) {
+		err = -ENOMEM;
+		goto err;
+	}
+
+	cl->tx_cfg.channels = kzalloc(cells * sizeof(channel), GFP_KERNEL);
+	if (!cl->tx_cfg.channels) {
+		err = -ENOMEM;
+		goto err2;
+	}
+
+	max_chan = 0;
+	for (i = 0; i < cells; i++) {
+		err = of_property_read_u32_index(client, "hsi-channel-ids", i,
+						 &channel.id);
+		if (err)
+			goto err3;
+
+		err = of_property_read_string_index(client, "hsi-channel-names",
+						    i, &channel.name);
+		if (err)
+			channel.name = NULL;
+
+		if (channel.id > max_chan)
+			max_chan = channel.id;
+
+		cl->rx_cfg.channels[i] = channel;
+		cl->tx_cfg.channels[i] = channel;
+	}
+
+	cl->rx_cfg.num_hw_channels = max_chan + 1;
+	cl->tx_cfg.num_hw_channels = max_chan + 1;
+
+	cl->device.bus = &hsi_bus_type;
+	cl->device.parent = &port->device;
+	cl->device.release = hsi_client_release;
+	cl->device.of_node = client;
+
+	if (device_register(&cl->device) < 0) {
+		pr_err("hsi: failed to register client: %s\n", name);
+		put_device(&cl->device);
+	}
+
+	return;
+
+err3:
+	kfree(cl->tx_cfg.channels);
+err2:
+	kfree(cl->rx_cfg.channels);
+err:
+	kfree(cl);
+	pr_err("hsi client: missing or incorrect of property: err=%d\n", err);
+}
+
+void hsi_add_clients_from_dt(struct hsi_port *port, struct device_node *clients)
+{
+	struct device_node *child;
+
+	/* register hsi-char device */
+	hsi_new_client(port, &hsi_char_dev_info);
+
+	for_each_available_child_of_node(clients, child)
+		hsi_add_client_from_dt(port, child);
+}
+EXPORT_SYMBOL_GPL(hsi_add_clients_from_dt);
+#endif
+
+int hsi_remove_client(struct device *dev, void *data __maybe_unused)
+{
+	device_unregister(dev);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hsi_remove_client);
+
+static int hsi_remove_port(struct device *dev, void *data __maybe_unused)
+{
+	device_for_each_child(dev, NULL, hsi_remove_client);
+	device_unregister(dev);
+
+	return 0;
+}
+
+static void hsi_controller_release(struct device *dev)
+{
+	struct hsi_controller *hsi = to_hsi_controller(dev);
+
+	kfree(hsi->port);
+	kfree(hsi);
+}
+
+static void hsi_port_release(struct device *dev)
+{
+	kfree(to_hsi_port(dev));
+}
+
+/**
+ * hsi_unregister_port - Unregister an HSI port
+ * @port: The HSI port to unregister
+ */
+void hsi_port_unregister_clients(struct hsi_port *port)
+{
+	device_for_each_child(&port->device, NULL, hsi_remove_client);
+}
+EXPORT_SYMBOL_GPL(hsi_port_unregister_clients);
+
+/**
+ * hsi_unregister_controller - Unregister an HSI controller
+ * @hsi: The HSI controller to register
+ */
+void hsi_unregister_controller(struct hsi_controller *hsi)
+{
+	device_for_each_child(&hsi->device, NULL, hsi_remove_port);
+	device_unregister(&hsi->device);
+}
+EXPORT_SYMBOL_GPL(hsi_unregister_controller);
+
+/**
+ * hsi_register_controller - Register an HSI controller and its ports
+ * @hsi: The HSI controller to register
+ *
+ * Returns -errno on failure, 0 on success.
+ */
+int hsi_register_controller(struct hsi_controller *hsi)
+{
+	unsigned int i;
+	int err;
+
+	err = device_add(&hsi->device);
+	if (err < 0)
+		return err;
+	for (i = 0; i < hsi->num_ports; i++) {
+		hsi->port[i]->device.parent = &hsi->device;
+		err = device_add(&hsi->port[i]->device);
+		if (err < 0)
+			goto out;
+	}
+	/* Populate HSI bus with HSI clients */
+	hsi_scan_board_info(hsi);
+
+	return 0;
+out:
+	while (i-- > 0)
+		device_del(&hsi->port[i]->device);
+	device_del(&hsi->device);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(hsi_register_controller);
+
+/**
+ * hsi_register_client_driver - Register an HSI client to the HSI bus
+ * @drv: HSI client driver to register
+ *
+ * Returns -errno on failure, 0 on success.
+ */
+int hsi_register_client_driver(struct hsi_client_driver *drv)
+{
+	drv->driver.bus = &hsi_bus_type;
+
+	return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(hsi_register_client_driver);
+
+static inline int hsi_dummy_msg(struct hsi_msg *msg __maybe_unused)
+{
+	return 0;
+}
+
+static inline int hsi_dummy_cl(struct hsi_client *cl __maybe_unused)
+{
+	return 0;
+}
+
+/**
+ * hsi_put_controller - Free an HSI controller
+ *
+ * @hsi: Pointer to the HSI controller to freed
+ *
+ * HSI controller drivers should only use this function if they need
+ * to free their allocated hsi_controller structures before a successful
+ * call to hsi_register_controller. Other use is not allowed.
+ */
+void hsi_put_controller(struct hsi_controller *hsi)
+{
+	unsigned int i;
+
+	if (!hsi)
+		return;
+
+	for (i = 0; i < hsi->num_ports; i++)
+		if (hsi->port && hsi->port[i])
+			put_device(&hsi->port[i]->device);
+	put_device(&hsi->device);
+}
+EXPORT_SYMBOL_GPL(hsi_put_controller);
+
+/**
+ * hsi_alloc_controller - Allocate an HSI controller and its ports
+ * @n_ports: Number of ports on the HSI controller
+ * @flags: Kernel allocation flags
+ *
+ * Return NULL on failure or a pointer to an hsi_controller on success.
+ */
+struct hsi_controller *hsi_alloc_controller(unsigned int n_ports, gfp_t flags)
+{
+	struct hsi_controller	*hsi;
+	struct hsi_port		**port;
+	unsigned int		i;
+
+	if (!n_ports)
+		return NULL;
+
+	hsi = kzalloc(sizeof(*hsi), flags);
+	if (!hsi)
+		return NULL;
+	port = kzalloc(sizeof(*port)*n_ports, flags);
+	if (!port) {
+		kfree(hsi);
+		return NULL;
+	}
+	hsi->num_ports = n_ports;
+	hsi->port = port;
+	hsi->device.release = hsi_controller_release;
+	device_initialize(&hsi->device);
+
+	for (i = 0; i < n_ports; i++) {
+		port[i] = kzalloc(sizeof(**port), flags);
+		if (port[i] == NULL)
+			goto out;
+		port[i]->num = i;
+		port[i]->async = hsi_dummy_msg;
+		port[i]->setup = hsi_dummy_cl;
+		port[i]->flush = hsi_dummy_cl;
+		port[i]->start_tx = hsi_dummy_cl;
+		port[i]->stop_tx = hsi_dummy_cl;
+		port[i]->release = hsi_dummy_cl;
+		mutex_init(&port[i]->lock);
+		BLOCKING_INIT_NOTIFIER_HEAD(&port[i]->n_head);
+		dev_set_name(&port[i]->device, "port%d", i);
+		hsi->port[i]->device.release = hsi_port_release;
+		device_initialize(&hsi->port[i]->device);
+	}
+
+	return hsi;
+out:
+	hsi_put_controller(hsi);
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(hsi_alloc_controller);
+
+/**
+ * hsi_free_msg - Free an HSI message
+ * @msg: Pointer to the HSI message
+ *
+ * Client is responsible to free the buffers pointed by the scatterlists.
+ */
+void hsi_free_msg(struct hsi_msg *msg)
+{
+	if (!msg)
+		return;
+	sg_free_table(&msg->sgt);
+	kfree(msg);
+}
+EXPORT_SYMBOL_GPL(hsi_free_msg);
+
+/**
+ * hsi_alloc_msg - Allocate an HSI message
+ * @nents: Number of memory entries
+ * @flags: Kernel allocation flags
+ *
+ * nents can be 0. This mainly makes sense for read transfer.
+ * In that case, HSI drivers will call the complete callback when
+ * there is data to be read without consuming it.
+ *
+ * Return NULL on failure or a pointer to an hsi_msg on success.
+ */
+struct hsi_msg *hsi_alloc_msg(unsigned int nents, gfp_t flags)
+{
+	struct hsi_msg *msg;
+	int err;
+
+	msg = kzalloc(sizeof(*msg), flags);
+	if (!msg)
+		return NULL;
+
+	if (!nents)
+		return msg;
+
+	err = sg_alloc_table(&msg->sgt, nents, flags);
+	if (unlikely(err)) {
+		kfree(msg);
+		msg = NULL;
+	}
+
+	return msg;
+}
+EXPORT_SYMBOL_GPL(hsi_alloc_msg);
+
+/**
+ * hsi_async - Submit an HSI transfer to the controller
+ * @cl: HSI client sending the transfer
+ * @msg: The HSI transfer passed to controller
+ *
+ * The HSI message must have the channel, ttype, complete and destructor
+ * fields set beforehand. If nents > 0 then the client has to initialize
+ * also the scatterlists to point to the buffers to write to or read from.
+ *
+ * HSI controllers relay on pre-allocated buffers from their clients and they
+ * do not allocate buffers on their own.
+ *
+ * Once the HSI message transfer finishes, the HSI controller calls the
+ * complete callback with the status and actual_len fields of the HSI message
+ * updated. The complete callback can be called before returning from
+ * hsi_async.
+ *
+ * Returns -errno on failure or 0 on success
+ */
+int hsi_async(struct hsi_client *cl, struct hsi_msg *msg)
+{
+	struct hsi_port *port = hsi_get_port(cl);
+
+	if (!hsi_port_claimed(cl))
+		return -EACCES;
+
+	WARN_ON_ONCE(!msg->destructor || !msg->complete);
+	msg->cl = cl;
+
+	return port->async(msg);
+}
+EXPORT_SYMBOL_GPL(hsi_async);
+
+/**
+ * hsi_claim_port - Claim the HSI client's port
+ * @cl: HSI client that wants to claim its port
+ * @share: Flag to indicate if the client wants to share the port or not.
+ *
+ * Returns -errno on failure, 0 on success.
+ */
+int hsi_claim_port(struct hsi_client *cl, unsigned int share)
+{
+	struct hsi_port *port = hsi_get_port(cl);
+	int err = 0;
+
+	mutex_lock(&port->lock);
+	if ((port->claimed) && (!port->shared || !share)) {
+		err = -EBUSY;
+		goto out;
+	}
+	if (!try_module_get(to_hsi_controller(port->device.parent)->owner)) {
+		err = -ENODEV;
+		goto out;
+	}
+	port->claimed++;
+	port->shared = !!share;
+	cl->pclaimed = 1;
+out:
+	mutex_unlock(&port->lock);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(hsi_claim_port);
+
+/**
+ * hsi_release_port - Release the HSI client's port
+ * @cl: HSI client which previously claimed its port
+ */
+void hsi_release_port(struct hsi_client *cl)
+{
+	struct hsi_port *port = hsi_get_port(cl);
+
+	mutex_lock(&port->lock);
+	/* Allow HW driver to do some cleanup */
+	port->release(cl);
+	if (cl->pclaimed)
+		port->claimed--;
+	BUG_ON(port->claimed < 0);
+	cl->pclaimed = 0;
+	if (!port->claimed)
+		port->shared = 0;
+	module_put(to_hsi_controller(port->device.parent)->owner);
+	mutex_unlock(&port->lock);
+}
+EXPORT_SYMBOL_GPL(hsi_release_port);
+
+static int hsi_event_notifier_call(struct notifier_block *nb,
+				unsigned long event, void *data __maybe_unused)
+{
+	struct hsi_client *cl = container_of(nb, struct hsi_client, nb);
+
+	(*cl->ehandler)(cl, event);
+
+	return 0;
+}
+
+/**
+ * hsi_register_port_event - Register a client to receive port events
+ * @cl: HSI client that wants to receive port events
+ * @handler: Event handler callback
+ *
+ * Clients should register a callback to be able to receive
+ * events from the ports. Registration should happen after
+ * claiming the port.
+ * The handler can be called in interrupt context.
+ *
+ * Returns -errno on error, or 0 on success.
+ */
+int hsi_register_port_event(struct hsi_client *cl,
+			void (*handler)(struct hsi_client *, unsigned long))
+{
+	struct hsi_port *port = hsi_get_port(cl);
+
+	if (!handler || cl->ehandler)
+		return -EINVAL;
+	if (!hsi_port_claimed(cl))
+		return -EACCES;
+	cl->ehandler = handler;
+	cl->nb.notifier_call = hsi_event_notifier_call;
+
+	return blocking_notifier_chain_register(&port->n_head, &cl->nb);
+}
+EXPORT_SYMBOL_GPL(hsi_register_port_event);
+
+/**
+ * hsi_unregister_port_event - Stop receiving port events for a client
+ * @cl: HSI client that wants to stop receiving port events
+ *
+ * Clients should call this function before releasing their associated
+ * port.
+ *
+ * Returns -errno on error, or 0 on success.
+ */
+int hsi_unregister_port_event(struct hsi_client *cl)
+{
+	struct hsi_port *port = hsi_get_port(cl);
+	int err;
+
+	WARN_ON(!hsi_port_claimed(cl));
+
+	err = blocking_notifier_chain_unregister(&port->n_head, &cl->nb);
+	if (!err)
+		cl->ehandler = NULL;
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(hsi_unregister_port_event);
+
+/**
+ * hsi_event - Notifies clients about port events
+ * @port: Port where the event occurred
+ * @event: The event type
+ *
+ * Clients should not be concerned about wake line behavior. However, due
+ * to a race condition in HSI HW protocol, clients need to be notified
+ * about wake line changes, so they can implement a workaround for it.
+ *
+ * Events:
+ * HSI_EVENT_START_RX - Incoming wake line high
+ * HSI_EVENT_STOP_RX - Incoming wake line down
+ *
+ * Returns -errno on error, or 0 on success.
+ */
+int hsi_event(struct hsi_port *port, unsigned long event)
+{
+	return blocking_notifier_call_chain(&port->n_head, event, NULL);
+}
+EXPORT_SYMBOL_GPL(hsi_event);
+
+/**
+ * hsi_get_channel_id_by_name - acquire channel id by channel name
+ * @cl: HSI client, which uses the channel
+ * @name: name the channel is known under
+ *
+ * Clients can call this function to get the hsi channel ids similar to
+ * requesting IRQs or GPIOs by name. This function assumes the same
+ * channel configuration is used for RX and TX.
+ *
+ * Returns -errno on error or channel id on success.
+ */
+int hsi_get_channel_id_by_name(struct hsi_client *cl, char *name)
+{
+	int i;
+
+	if (!cl->rx_cfg.channels)
+		return -ENOENT;
+
+	for (i = 0; i < cl->rx_cfg.num_channels; i++)
+		if (!strcmp(cl->rx_cfg.channels[i].name, name))
+			return cl->rx_cfg.channels[i].id;
+
+	return -ENXIO;
+}
+EXPORT_SYMBOL_GPL(hsi_get_channel_id_by_name);
+
+static int __init hsi_init(void)
+{
+	return bus_register(&hsi_bus_type);
+}
+postcore_initcall(hsi_init);
+
+static void __exit hsi_exit(void)
+{
+	bus_unregister(&hsi_bus_type);
+}
+module_exit(hsi_exit);
+
+MODULE_AUTHOR("Carlos Chinea <carlos.chinea@nokia.com>");
+MODULE_DESCRIPTION("High-speed Synchronous Serial Interface (HSI) framework");
+MODULE_LICENSE("GPL v2");