1 files changed, 477 insertions, 326 deletions

diff --git a/drivers/mailbox/omap-mailbox.c b/drivers/mailbox/omap-mailbox.c
index d79a646b9042..17fe6545875d 100644
--- a/drivers/mailbox/omap-mailbox.c
+++ b/drivers/mailbox/omap-mailbox.c
@@ -1,199 +1,195 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * OMAP mailbox driver
  *
  * Copyright (C) 2006-2009 Nokia Corporation. All rights reserved.
+ * Copyright (C) 2013-2021 Texas Instruments Incorporated - https://www.ti.com
  *
  * Contact: Hiroshi DOYU <Hiroshi.DOYU@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
- *
+ *          Suman Anna <s-anna@ti.com>
  */
 
 #include <linux/interrupt.h>
 #include <linux/spinlock.h>
 #include <linux/mutex.h>
-#include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/kfifo.h>
 #include <linux/err.h>
-#include <linux/notifier.h>
+#include <linux/io.h>
 #include <linux/module.h>
-
-#include "omap-mbox.h"
-
-static struct omap_mbox **mboxes;
-
-static int mbox_configured;
-static DEFINE_MUTEX(mbox_configured_lock);
-
-static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE;
-module_param(mbox_kfifo_size, uint, S_IRUGO);
-MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)");
-
-/* Mailbox FIFO handle functions */
-static inline mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox)
-{
-	return mbox->ops->fifo_read(mbox);
-}
-static inline void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
-{
-	mbox->ops->fifo_write(mbox, msg);
-}
-static inline int mbox_fifo_empty(struct omap_mbox *mbox)
-{
-	return mbox->ops->fifo_empty(mbox);
-}
-static inline int mbox_fifo_full(struct omap_mbox *mbox)
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/mailbox_controller.h>
+#include <linux/mailbox_client.h>
+
+#include "mailbox.h"
+
+#define MAILBOX_REVISION		0x000
+#define MAILBOX_MESSAGE(m)		(0x040 + 4 * (m))
+#define MAILBOX_FIFOSTATUS(m)		(0x080 + 4 * (m))
+#define MAILBOX_MSGSTATUS(m)		(0x0c0 + 4 * (m))
+
+#define OMAP2_MAILBOX_IRQSTATUS(u)	(0x100 + 8 * (u))
+#define OMAP2_MAILBOX_IRQENABLE(u)	(0x104 + 8 * (u))
+
+#define OMAP4_MAILBOX_IRQSTATUS(u)	(0x104 + 0x10 * (u))
+#define OMAP4_MAILBOX_IRQENABLE(u)	(0x108 + 0x10 * (u))
+#define OMAP4_MAILBOX_IRQENABLE_CLR(u)	(0x10c + 0x10 * (u))
+
+#define MAILBOX_IRQSTATUS(type, u)	(type ? OMAP4_MAILBOX_IRQSTATUS(u) : \
+						OMAP2_MAILBOX_IRQSTATUS(u))
+#define MAILBOX_IRQENABLE(type, u)	(type ? OMAP4_MAILBOX_IRQENABLE(u) : \
+						OMAP2_MAILBOX_IRQENABLE(u))
+#define MAILBOX_IRQDISABLE(type, u)	(type ? OMAP4_MAILBOX_IRQENABLE_CLR(u) \
+						: OMAP2_MAILBOX_IRQENABLE(u))
+
+#define MAILBOX_IRQ_NEWMSG(m)		(1 << (2 * (m)))
+#define MAILBOX_IRQ_NOTFULL(m)		(1 << (2 * (m) + 1))
+
+/* Interrupt register configuration types */
+#define MBOX_INTR_CFG_TYPE1		0
+#define MBOX_INTR_CFG_TYPE2		1
+
+typedef enum {
+	IRQ_TX = 1,
+	IRQ_RX = 2,
+} omap_mbox_irq_t;
+
+struct omap_mbox_fifo {
+	unsigned long msg;
+	unsigned long fifo_stat;
+	unsigned long msg_stat;
+	unsigned long irqenable;
+	unsigned long irqstatus;
+	unsigned long irqdisable;
+	u32 intr_bit;
+};
+
+struct omap_mbox_match_data {
+	u32 intr_type;
+	bool is_exclusive;
+};
+
+struct omap_mbox_device {
+	struct device *dev;
+	struct mutex cfg_lock;
+	void __iomem *mbox_base;
+	u32 *irq_ctx;
+	u32 num_users;
+	u32 num_fifos;
+	u32 intr_type;
+	const struct omap_mbox_match_data *mbox_data;
+};
+
+struct omap_mbox {
+	const char		*name;
+	int			irq;
+	struct omap_mbox_device *parent;
+	struct omap_mbox_fifo	tx_fifo;
+	struct omap_mbox_fifo	rx_fifo;
+	u32			intr_type;
+	struct mbox_chan	*chan;
+	bool			send_no_irq;
+};
+
+static inline
+unsigned int mbox_read_reg(struct omap_mbox_device *mdev, size_t ofs)
 {
-	return mbox->ops->fifo_full(mbox);
+	return __raw_readl(mdev->mbox_base + ofs);
 }
 
-/* Mailbox IRQ handle functions */
-static inline void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
-{
-	if (mbox->ops->ack_irq)
-		mbox->ops->ack_irq(mbox, irq);
-}
-static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+static inline
+void mbox_write_reg(struct omap_mbox_device *mdev, u32 val, size_t ofs)
 {
-	return mbox->ops->is_irq(mbox, irq);
+	__raw_writel(val, mdev->mbox_base + ofs);
 }
 
-/*
- * message sender
- */
-static int __mbox_poll_for_space(struct omap_mbox *mbox)
+/* Mailbox FIFO handle functions */
+static u32 mbox_fifo_read(struct omap_mbox *mbox)
 {
-	int ret = 0, i = 1000;
-
-	while (mbox_fifo_full(mbox)) {
-		if (mbox->ops->type == OMAP_MBOX_TYPE2)
-			return -1;
-		if (--i == 0)
-			return -1;
-		udelay(1);
-	}
-	return ret;
+	struct omap_mbox_fifo *fifo = &mbox->rx_fifo;
+
+	return mbox_read_reg(mbox->parent, fifo->msg);
 }
 
-int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
+static void mbox_fifo_write(struct omap_mbox *mbox, u32 msg)
 {
-	struct omap_mbox_queue *mq = mbox->txq;
-	int ret = 0, len;
-
-	spin_lock_bh(&mq->lock);
-
-	if (kfifo_avail(&mq->fifo) < sizeof(msg)) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	if (kfifo_is_empty(&mq->fifo) && !__mbox_poll_for_space(mbox)) {
-		mbox_fifo_write(mbox, msg);
-		goto out;
-	}
-
-	len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
-	WARN_ON(len != sizeof(msg));
+	struct omap_mbox_fifo *fifo = &mbox->tx_fifo;
 
-	tasklet_schedule(&mbox->txq->tasklet);
-
-out:
-	spin_unlock_bh(&mq->lock);
-	return ret;
+	mbox_write_reg(mbox->parent, msg, fifo->msg);
 }
-EXPORT_SYMBOL(omap_mbox_msg_send);
 
-void omap_mbox_save_ctx(struct omap_mbox *mbox)
+static int mbox_fifo_empty(struct omap_mbox *mbox)
 {
-	if (!mbox->ops->save_ctx) {
-		dev_err(mbox->dev, "%s:\tno save\n", __func__);
-		return;
-	}
+	struct omap_mbox_fifo *fifo = &mbox->rx_fifo;
 
-	mbox->ops->save_ctx(mbox);
+	return (mbox_read_reg(mbox->parent, fifo->msg_stat) == 0);
 }
-EXPORT_SYMBOL(omap_mbox_save_ctx);
 
-void omap_mbox_restore_ctx(struct omap_mbox *mbox)
+static int mbox_fifo_full(struct omap_mbox *mbox)
 {
-	if (!mbox->ops->restore_ctx) {
-		dev_err(mbox->dev, "%s:\tno restore\n", __func__);
-		return;
-	}
+	struct omap_mbox_fifo *fifo = &mbox->tx_fifo;
 
-	mbox->ops->restore_ctx(mbox);
+	return mbox_read_reg(mbox->parent, fifo->fifo_stat);
 }
-EXPORT_SYMBOL(omap_mbox_restore_ctx);
 
-void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+/* Mailbox IRQ handle functions */
+static void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
 {
-	mbox->ops->enable_irq(mbox, irq);
-}
-EXPORT_SYMBOL(omap_mbox_enable_irq);
+	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
+				&mbox->tx_fifo : &mbox->rx_fifo;
+	u32 bit = fifo->intr_bit;
+	u32 irqstatus = fifo->irqstatus;
 
-void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
-{
-	mbox->ops->disable_irq(mbox, irq);
+	mbox_write_reg(mbox->parent, bit, irqstatus);
+
+	/* Flush posted write for irq status to avoid spurious interrupts */
+	mbox_read_reg(mbox->parent, irqstatus);
 }
-EXPORT_SYMBOL(omap_mbox_disable_irq);
 
-static void mbox_tx_tasklet(unsigned long tx_data)
+static int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
 {
-	struct omap_mbox *mbox = (struct omap_mbox *)tx_data;
-	struct omap_mbox_queue *mq = mbox->txq;
-	mbox_msg_t msg;
-	int ret;
+	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
+				&mbox->tx_fifo : &mbox->rx_fifo;
+	u32 bit = fifo->intr_bit;
+	u32 irqenable = fifo->irqenable;
+	u32 irqstatus = fifo->irqstatus;
 
-	while (kfifo_len(&mq->fifo)) {
-		if (__mbox_poll_for_space(mbox)) {
-			omap_mbox_enable_irq(mbox, IRQ_TX);
-			break;
-		}
+	u32 enable = mbox_read_reg(mbox->parent, irqenable);
+	u32 status = mbox_read_reg(mbox->parent, irqstatus);
 
-		ret = kfifo_out(&mq->fifo, (unsigned char *)&msg,
-								sizeof(msg));
-		WARN_ON(ret != sizeof(msg));
+	return (int)(enable & status & bit);
+}
 
-		mbox_fifo_write(mbox, msg);
-	}
+static void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+{
+	u32 l;
+	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
+				&mbox->tx_fifo : &mbox->rx_fifo;
+	u32 bit = fifo->intr_bit;
+	u32 irqenable = fifo->irqenable;
+
+	l = mbox_read_reg(mbox->parent, irqenable);
+	l |= bit;
+	mbox_write_reg(mbox->parent, l, irqenable);
 }
 
-/*
- * Message receiver(workqueue)
- */
-static void mbox_rx_work(struct work_struct *work)
+static void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
 {
-	struct omap_mbox_queue *mq =
-			container_of(work, struct omap_mbox_queue, work);
-	mbox_msg_t msg;
-	int len;
-
-	while (kfifo_len(&mq->fifo) >= sizeof(msg)) {
-		len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
-		WARN_ON(len != sizeof(msg));
-
-		blocking_notifier_call_chain(&mq->mbox->notifier, len,
-								(void *)msg);
-		spin_lock_irq(&mq->lock);
-		if (mq->full) {
-			mq->full = false;
-			omap_mbox_enable_irq(mq->mbox, IRQ_RX);
-		}
-		spin_unlock_irq(&mq->lock);
-	}
+	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
+				&mbox->tx_fifo : &mbox->rx_fifo;
+	u32 bit = fifo->intr_bit;
+	u32 irqdisable = fifo->irqdisable;
+
+	/*
+	 * Read and update the interrupt configuration register for pre-OMAP4.
+	 * OMAP4 and later SoCs have a dedicated interrupt disabling register.
+	 */
+	if (!mbox->intr_type)
+		bit = mbox_read_reg(mbox->parent, irqdisable) & ~bit;
+
+	mbox_write_reg(mbox->parent, bit, irqdisable);
 }
 
 /*
@@ -203,35 +199,20 @@ static void __mbox_tx_interrupt(struct omap_mbox *mbox)
 {
 	omap_mbox_disable_irq(mbox, IRQ_TX);
 	ack_mbox_irq(mbox, IRQ_TX);
-	tasklet_schedule(&mbox->txq->tasklet);
+	mbox_chan_txdone(mbox->chan, 0);
 }
 
 static void __mbox_rx_interrupt(struct omap_mbox *mbox)
 {
-	struct omap_mbox_queue *mq = mbox->rxq;
-	mbox_msg_t msg;
-	int len;
+	u32 msg;
 
 	while (!mbox_fifo_empty(mbox)) {
-		if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
-			omap_mbox_disable_irq(mbox, IRQ_RX);
-			mq->full = true;
-			goto nomem;
-		}
-
 		msg = mbox_fifo_read(mbox);
-
-		len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
-		WARN_ON(len != sizeof(msg));
-
-		if (mbox->ops->type == OMAP_MBOX_TYPE1)
-			break;
+		mbox_chan_received_data(mbox->chan, (void *)(uintptr_t)msg);
 	}
 
-	/* no more messages in the fifo. clear IRQ source. */
+	/* clear IRQ source. */
 	ack_mbox_irq(mbox, IRQ_RX);
-nomem:
-	schedule_work(&mbox->rxq->work);
 }
 
 static irqreturn_t mbox_interrupt(int irq, void *p)
@@ -247,221 +228,391 @@ static irqreturn_t mbox_interrupt(int irq, void *p)
 	return IRQ_HANDLED;
 }
 
-static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
-					void (*work) (struct work_struct *),
-					void (*tasklet)(unsigned long))
+static int omap_mbox_startup(struct omap_mbox *mbox)
 {
-	struct omap_mbox_queue *mq;
-
-	mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
-	if (!mq)
-		return NULL;
+	int ret = 0;
 
-	spin_lock_init(&mq->lock);
+	ret = request_threaded_irq(mbox->irq, NULL, mbox_interrupt,
+				   IRQF_SHARED | IRQF_ONESHOT, mbox->name,
+				   mbox);
+	if (unlikely(ret)) {
+		pr_err("failed to register mailbox interrupt:%d\n", ret);
+		return ret;
+	}
 
-	if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
-		goto error;
+	if (mbox->send_no_irq)
+		mbox->chan->txdone_method = TXDONE_BY_ACK;
 
-	if (work)
-		INIT_WORK(&mq->work, work);
+	omap_mbox_enable_irq(mbox, IRQ_RX);
 
-	if (tasklet)
-		tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox);
-	return mq;
-error:
-	kfree(mq);
-	return NULL;
+	return 0;
 }
 
-static void mbox_queue_free(struct omap_mbox_queue *q)
+static void omap_mbox_fini(struct omap_mbox *mbox)
 {
-	kfifo_free(&q->fifo);
-	kfree(q);
+	omap_mbox_disable_irq(mbox, IRQ_RX);
+	free_irq(mbox->irq, mbox);
 }
 
-static int omap_mbox_startup(struct omap_mbox *mbox)
+static int omap_mbox_chan_startup(struct mbox_chan *chan)
 {
+	struct omap_mbox *mbox = chan->con_priv;
+	struct omap_mbox_device *mdev = mbox->parent;
 	int ret = 0;
-	struct omap_mbox_queue *mq;
-
-	mutex_lock(&mbox_configured_lock);
-	if (!mbox_configured++) {
-		if (likely(mbox->ops->startup)) {
-			ret = mbox->ops->startup(mbox);
-			if (unlikely(ret))
-				goto fail_startup;
-		} else
-			goto fail_startup;
-	}
 
-	if (!mbox->use_count++) {
-		mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet);
-		if (!mq) {
-			ret = -ENOMEM;
-			goto fail_alloc_txq;
-		}
-		mbox->txq = mq;
+	mutex_lock(&mdev->cfg_lock);
+	pm_runtime_get_sync(mdev->dev);
+	ret = omap_mbox_startup(mbox);
+	if (ret)
+		pm_runtime_put_sync(mdev->dev);
+	mutex_unlock(&mdev->cfg_lock);
+	return ret;
+}
 
-		mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL);
-		if (!mq) {
-			ret = -ENOMEM;
-			goto fail_alloc_rxq;
-		}
-		mbox->rxq = mq;
-		mq->mbox = mbox;
-		ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
-							mbox->name, mbox);
-		if (unlikely(ret)) {
-			pr_err("failed to register mailbox interrupt:%d\n",
-									ret);
-			goto fail_request_irq;
-		}
+static void omap_mbox_chan_shutdown(struct mbox_chan *chan)
+{
+	struct omap_mbox *mbox = chan->con_priv;
+	struct omap_mbox_device *mdev = mbox->parent;
 
-		omap_mbox_enable_irq(mbox, IRQ_RX);
-	}
-	mutex_unlock(&mbox_configured_lock);
-	return 0;
+	mutex_lock(&mdev->cfg_lock);
+	omap_mbox_fini(mbox);
+	pm_runtime_put_sync(mdev->dev);
+	mutex_unlock(&mdev->cfg_lock);
+}
 
-fail_request_irq:
-	mbox_queue_free(mbox->rxq);
-fail_alloc_rxq:
-	mbox_queue_free(mbox->txq);
-fail_alloc_txq:
-	if (mbox->ops->shutdown)
-		mbox->ops->shutdown(mbox);
-	mbox->use_count--;
-fail_startup:
-	mbox_configured--;
-	mutex_unlock(&mbox_configured_lock);
-	return ret;
+static int omap_mbox_chan_send_noirq(struct omap_mbox *mbox, u32 msg)
+{
+	if (mbox_fifo_full(mbox))
+		return -EBUSY;
+
+	omap_mbox_enable_irq(mbox, IRQ_RX);
+	mbox_fifo_write(mbox, msg);
+	omap_mbox_disable_irq(mbox, IRQ_RX);
+
+	/* we must read and ack the interrupt directly from here */
+	mbox_fifo_read(mbox);
+	ack_mbox_irq(mbox, IRQ_RX);
+
+	return 0;
 }
 
-static void omap_mbox_fini(struct omap_mbox *mbox)
+static int omap_mbox_chan_send(struct omap_mbox *mbox, u32 msg)
 {
-	mutex_lock(&mbox_configured_lock);
-
-	if (!--mbox->use_count) {
-		omap_mbox_disable_irq(mbox, IRQ_RX);
-		free_irq(mbox->irq, mbox);
-		tasklet_kill(&mbox->txq->tasklet);
-		flush_work(&mbox->rxq->work);
-		mbox_queue_free(mbox->txq);
-		mbox_queue_free(mbox->rxq);
+	if (mbox_fifo_full(mbox)) {
+		/* always enable the interrupt */
+		omap_mbox_enable_irq(mbox, IRQ_TX);
+		return -EBUSY;
 	}
 
-	if (likely(mbox->ops->shutdown)) {
-		if (!--mbox_configured)
-			mbox->ops->shutdown(mbox);
-	}
+	mbox_fifo_write(mbox, msg);
 
-	mutex_unlock(&mbox_configured_lock);
+	/* always enable the interrupt */
+	omap_mbox_enable_irq(mbox, IRQ_TX);
+	return 0;
 }
 
-struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb)
+static int omap_mbox_chan_send_data(struct mbox_chan *chan, void *data)
 {
-	struct omap_mbox *_mbox, *mbox = NULL;
-	int i, ret;
+	struct omap_mbox *mbox = chan->con_priv;
+	int ret;
+	u32 msg = (u32)(uintptr_t)(data);
 
-	if (!mboxes)
-		return ERR_PTR(-EINVAL);
+	if (!mbox)
+		return -EINVAL;
 
-	for (i = 0; (_mbox = mboxes[i]); i++) {
-		if (!strcmp(_mbox->name, name)) {
-			mbox = _mbox;
-			break;
-		}
-	}
+	if (mbox->send_no_irq)
+		ret = omap_mbox_chan_send_noirq(mbox, msg);
+	else
+		ret = omap_mbox_chan_send(mbox, msg);
 
-	if (!mbox)
-		return ERR_PTR(-ENOENT);
+	return ret;
+}
 
-	if (nb)
-		blocking_notifier_chain_register(&mbox->notifier, nb);
+static const struct mbox_chan_ops omap_mbox_chan_ops = {
+	.startup        = omap_mbox_chan_startup,
+	.send_data      = omap_mbox_chan_send_data,
+	.shutdown       = omap_mbox_chan_shutdown,
+};
 
-	ret = omap_mbox_startup(mbox);
-	if (ret) {
-		blocking_notifier_chain_unregister(&mbox->notifier, nb);
-		return ERR_PTR(-ENODEV);
+#ifdef CONFIG_PM_SLEEP
+static int omap_mbox_suspend(struct device *dev)
+{
+	struct omap_mbox_device *mdev = dev_get_drvdata(dev);
+	u32 usr, fifo, reg;
+
+	if (pm_runtime_status_suspended(dev))
+		return 0;
+
+	if (mdev->mbox_data->is_exclusive) {
+		for (fifo = 0; fifo < mdev->num_fifos; fifo++) {
+			if (mbox_read_reg(mdev, MAILBOX_MSGSTATUS(fifo))) {
+				dev_err(mdev->dev, "fifo %d has unexpected unread messages\n",
+					fifo);
+				return -EBUSY;
+			}
+		}
+	}
+
+	for (usr = 0; usr < mdev->num_users; usr++) {
+		reg = MAILBOX_IRQENABLE(mdev->intr_type, usr);
+		mdev->irq_ctx[usr] = mbox_read_reg(mdev, reg);
 	}
 
-	return mbox;
+	return 0;
 }
-EXPORT_SYMBOL(omap_mbox_get);
 
-void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb)
+static int omap_mbox_resume(struct device *dev)
 {
-	blocking_notifier_chain_unregister(&mbox->notifier, nb);
-	omap_mbox_fini(mbox);
-}
-EXPORT_SYMBOL(omap_mbox_put);
+	struct omap_mbox_device *mdev = dev_get_drvdata(dev);
+	u32 usr, reg;
 
-static struct class omap_mbox_class = { .name = "mbox", };
+	if (pm_runtime_status_suspended(dev))
+		return 0;
+
+	for (usr = 0; usr < mdev->num_users; usr++) {
+		reg = MAILBOX_IRQENABLE(mdev->intr_type, usr);
+		mbox_write_reg(mdev, mdev->irq_ctx[usr], reg);
+	}
 
-int omap_mbox_register(struct device *parent, struct omap_mbox **list)
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops omap_mbox_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(omap_mbox_suspend, omap_mbox_resume)
+};
+
+static const struct omap_mbox_match_data omap2_data = { MBOX_INTR_CFG_TYPE1, true };
+static const struct omap_mbox_match_data omap4_data = { MBOX_INTR_CFG_TYPE2, true };
+static const struct omap_mbox_match_data am654_data = { MBOX_INTR_CFG_TYPE2, false };
+
+static const struct of_device_id omap_mailbox_of_match[] = {
+	{
+		.compatible	= "ti,omap2-mailbox",
+		.data		= &omap2_data,
+	},
+	{
+		.compatible	= "ti,omap3-mailbox",
+		.data		= &omap2_data,
+	},
+	{
+		.compatible	= "ti,omap4-mailbox",
+		.data		= &omap4_data,
+	},
+	{
+		.compatible	= "ti,am654-mailbox",
+		.data		= &am654_data,
+	},
+	{
+		.compatible	= "ti,am64-mailbox",
+		.data		= &am654_data,
+	},
+	{
+		/* end */
+	},
+};
+MODULE_DEVICE_TABLE(of, omap_mailbox_of_match);
+
+static struct mbox_chan *omap_mbox_of_xlate(struct mbox_controller *controller,
+					    const struct of_phandle_args *sp)
 {
-	int ret;
+	phandle phandle = sp->args[0];
+	struct device_node *node;
+	struct omap_mbox_device *mdev;
+	struct omap_mbox *mbox;
 	int i;
 
-	mboxes = list;
-	if (!mboxes)
-		return -EINVAL;
+	mdev = dev_get_drvdata(controller->dev);
+	if (WARN_ON(!mdev))
+		return ERR_PTR(-EINVAL);
 
-	for (i = 0; mboxes[i]; i++) {
-		struct omap_mbox *mbox = mboxes[i];
-		mbox->dev = device_create(&omap_mbox_class,
-				parent, 0, mbox, "%s", mbox->name);
-		if (IS_ERR(mbox->dev)) {
-			ret = PTR_ERR(mbox->dev);
-			goto err_out;
-		}
+	node = of_find_node_by_phandle(phandle);
+	if (!node) {
+		pr_err("%s: could not find node phandle 0x%x\n",
+		       __func__, phandle);
+		return ERR_PTR(-ENODEV);
+	}
 
-		BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier);
+	for (i = 0; i < controller->num_chans; i++) {
+		mbox = controller->chans[i].con_priv;
+		if (!strcmp(mbox->name, node->name)) {
+			of_node_put(node);
+			return &controller->chans[i];
+		}
 	}
-	return 0;
 
-err_out:
-	while (i--)
-		device_unregister(mboxes[i]->dev);
-	return ret;
+	of_node_put(node);
+	return ERR_PTR(-ENOENT);
 }
-EXPORT_SYMBOL(omap_mbox_register);
 
-int omap_mbox_unregister(void)
+static int omap_mbox_probe(struct platform_device *pdev)
 {
+	int ret;
+	struct mbox_chan *chnls;
+	struct omap_mbox *mbox;
+	struct omap_mbox_device *mdev;
+	struct omap_mbox_fifo *fifo;
+	struct device_node *node = pdev->dev.of_node;
+	struct device_node *child;
+	struct mbox_controller *controller;
+	u32 intr_type, info_count;
+	u32 num_users, num_fifos;
+	u32 tmp[3];
+	u32 l;
 	int i;
 
-	if (!mboxes)
-		return -EINVAL;
+	if (!node) {
+		pr_err("%s: only DT-based devices are supported\n", __func__);
+		return -ENODEV;
+	}
 
-	for (i = 0; mboxes[i]; i++)
-		device_unregister(mboxes[i]->dev);
-	mboxes = NULL;
-	return 0;
-}
-EXPORT_SYMBOL(omap_mbox_unregister);
+	if (of_property_read_u32(node, "ti,mbox-num-users", &num_users))
+		return -ENODEV;
 
-static int __init omap_mbox_init(void)
-{
-	int err;
+	if (of_property_read_u32(node, "ti,mbox-num-fifos", &num_fifos))
+		return -ENODEV;
 
-	err = class_register(&omap_mbox_class);
-	if (err)
-		return err;
+	info_count = of_get_available_child_count(node);
+	if (!info_count) {
+		dev_err(&pdev->dev, "no available mbox devices found\n");
+		return -ENODEV;
+	}
 
-	/* kfifo size sanity check: alignment and minimal size */
-	mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(mbox_msg_t));
-	mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size,
-							sizeof(mbox_msg_t));
+	mdev = devm_kzalloc(&pdev->dev, sizeof(*mdev), GFP_KERNEL);
+	if (!mdev)
+		return -ENOMEM;
+
+	mdev->mbox_data = device_get_match_data(&pdev->dev);
+	if (!mdev->mbox_data)
+		return -ENODEV;
+
+	intr_type = mdev->mbox_data->intr_type;
+
+	mdev->mbox_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(mdev->mbox_base))
+		return PTR_ERR(mdev->mbox_base);
+
+	mdev->irq_ctx = devm_kcalloc(&pdev->dev, num_users, sizeof(u32),
+				     GFP_KERNEL);
+	if (!mdev->irq_ctx)
+		return -ENOMEM;
+
+	chnls = devm_kcalloc(&pdev->dev, info_count + 1, sizeof(*chnls),
+			     GFP_KERNEL);
+	if (!chnls)
+		return -ENOMEM;
+
+	child = NULL;
+	for (i = 0; i < info_count; i++) {
+		int tx_id, tx_irq, tx_usr;
+		int rx_id,         rx_usr;
+
+		mbox = devm_kzalloc(&pdev->dev, sizeof(*mbox), GFP_KERNEL);
+		if (!mbox)
+			return -ENOMEM;
+
+		child = of_get_next_available_child(node, child);
+		ret = of_property_read_u32_array(child, "ti,mbox-tx", tmp,
+						 ARRAY_SIZE(tmp));
+		if (ret)
+			return ret;
+		tx_id = tmp[0];
+		tx_irq = tmp[1];
+		tx_usr = tmp[2];
+
+		ret = of_property_read_u32_array(child, "ti,mbox-rx", tmp,
+						 ARRAY_SIZE(tmp));
+		if (ret)
+			return ret;
+		rx_id = tmp[0];
+		/* rx_irq = tmp[1]; */
+		rx_usr = tmp[2];
+
+		if (tx_id >= num_fifos || rx_id >= num_fifos ||
+		    tx_usr >= num_users || rx_usr >= num_users)
+			return -EINVAL;
+
+		fifo = &mbox->tx_fifo;
+		fifo->msg = MAILBOX_MESSAGE(tx_id);
+		fifo->fifo_stat = MAILBOX_FIFOSTATUS(tx_id);
+		fifo->intr_bit = MAILBOX_IRQ_NOTFULL(tx_id);
+		fifo->irqenable = MAILBOX_IRQENABLE(intr_type, tx_usr);
+		fifo->irqstatus = MAILBOX_IRQSTATUS(intr_type, tx_usr);
+		fifo->irqdisable = MAILBOX_IRQDISABLE(intr_type, tx_usr);
+
+		fifo = &mbox->rx_fifo;
+		fifo->msg = MAILBOX_MESSAGE(rx_id);
+		fifo->msg_stat =  MAILBOX_MSGSTATUS(rx_id);
+		fifo->intr_bit = MAILBOX_IRQ_NEWMSG(rx_id);
+		fifo->irqenable = MAILBOX_IRQENABLE(intr_type, rx_usr);
+		fifo->irqstatus = MAILBOX_IRQSTATUS(intr_type, rx_usr);
+		fifo->irqdisable = MAILBOX_IRQDISABLE(intr_type, rx_usr);
+
+		mbox->send_no_irq = of_property_read_bool(child, "ti,mbox-send-noirq");
+		mbox->intr_type = intr_type;
+
+		mbox->parent = mdev;
+		mbox->name = child->name;
+		mbox->irq = platform_get_irq(pdev, tx_irq);
+		if (mbox->irq < 0)
+			return mbox->irq;
+		mbox->chan = &chnls[i];
+		chnls[i].con_priv = mbox;
+	}
+
+	mutex_init(&mdev->cfg_lock);
+	mdev->dev = &pdev->dev;
+	mdev->num_users = num_users;
+	mdev->num_fifos = num_fifos;
+	mdev->intr_type = intr_type;
+
+	controller = devm_kzalloc(&pdev->dev, sizeof(*controller), GFP_KERNEL);
+	if (!controller)
+		return -ENOMEM;
+	/*
+	 * OMAP/K3 Mailbox IP does not have a Tx-Done IRQ, but rather a Tx-Ready
+	 * IRQ and is needed to run the Tx state machine
+	 */
+	controller->txdone_irq = true;
+	controller->dev = mdev->dev;
+	controller->ops = &omap_mbox_chan_ops;
+	controller->chans = chnls;
+	controller->num_chans = info_count;
+	controller->of_xlate = omap_mbox_of_xlate;
+	ret = devm_mbox_controller_register(mdev->dev, controller);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, mdev);
+	devm_pm_runtime_enable(mdev->dev);
+
+	ret = pm_runtime_resume_and_get(mdev->dev);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * just print the raw revision register, the format is not
+	 * uniform across all SoCs
+	 */
+	l = mbox_read_reg(mdev, MAILBOX_REVISION);
+	dev_info(mdev->dev, "omap mailbox rev 0x%x\n", l);
+
+	ret = pm_runtime_put_sync(mdev->dev);
+	if (ret < 0 && ret != -ENOSYS)
+		return ret;
 
 	return 0;
 }
-subsys_initcall(omap_mbox_init);
 
-static void __exit omap_mbox_exit(void)
-{
-	class_unregister(&omap_mbox_class);
-}
-module_exit(omap_mbox_exit);
+static struct platform_driver omap_mbox_driver = {
+	.probe	= omap_mbox_probe,
+	.driver	= {
+		.name = "omap-mailbox",
+		.pm = &omap_mbox_pm_ops,
+		.of_match_table = omap_mailbox_of_match,
+	},
+};
+module_platform_driver(omap_mbox_driver);
 
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");