mailbox/omap: adapt to the new mailbox framework
The OMAP mailbox driver and its existing clients (remoteproc
for OMAP4+) are adapted to use the generic mailbox framework.
The main changes for the adaptation are:
- The tasklet used for Tx is replaced with the state machine from
the generic mailbox framework. The workqueue used for processing
the received messages stays intact for minimizing the effects on
the OMAP mailbox clients.
- The existing exported client API, omap_mbox_get, omap_mbox_put and
omap_mbox_send_msg are deleted, as the framework provides equivalent
functionality. A OMAP-specific omap_mbox_request_channel is added
though to support non-DT way of requesting mailboxes.
- The OMAP mailbox driver is integrated with the mailbox framework
through the proper implementations of mbox_chan_ops, except for
.last_tx_done and .peek_data. The OMAP mailbox driver does not need
these ops, as it is completely interrupt driven.
- The OMAP mailbox driver uses a custom of_xlate controller ops that
allows phandles for the pargs specifier instead of indexing to avoid
any channel registration order dependencies.
- The new framework does not support multiple clients operating on a
single channel, so the reference counting logic is simplified.
- The remoteproc driver (current client) is adapted to use the new API.
The notifier callbacks used within this client is replaced with the
regular callbacks from the newer framework.
- The exported OMAP mailbox API are limited to omap_mbox_save_ctx,
omap_mbox_restore_ctx, omap_mbox_enable_irq & omap_mbox_disable_irq,
with the signature modified to take in the new mbox_chan handle instead
of the OMAP specific omap_mbox handle. The first 2 will be removed when
the OMAP mailbox driver is adapted to runtime_pm. The other exported
API omap_mbox_request_channel will be removed once existing legacy
users are converted to DT.
Signed-off-by: Suman Anna <s-anna@ti.com>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
diff --git a/drivers/mailbox/omap-mailbox.c b/drivers/mailbox/omap-mailbox.c
index bcc7ee1..66b83ca 100644
--- a/drivers/mailbox/omap-mailbox.c
+++ b/drivers/mailbox/omap-mailbox.c
@@ -29,13 +29,14 @@
#include <linux/slab.h>
#include <linux/kfifo.h>
#include <linux/err.h>
-#include <linux/notifier.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/platform_data/mailbox-omap.h>
#include <linux/omap-mailbox.h>
+#include <linux/mailbox_controller.h>
+#include <linux/mailbox_client.h>
#define MAILBOX_REVISION 0x000
#define MAILBOX_MESSAGE(m) (0x040 + 4 * (m))
@@ -80,7 +81,6 @@
spinlock_t lock;
struct kfifo fifo;
struct work_struct work;
- struct tasklet_struct tasklet;
struct omap_mbox *mbox;
bool full;
};
@@ -92,6 +92,7 @@
u32 num_users;
u32 num_fifos;
struct omap_mbox **mboxes;
+ struct mbox_controller controller;
struct list_head elem;
};
@@ -110,15 +111,14 @@
struct omap_mbox {
const char *name;
int irq;
- struct omap_mbox_queue *txq, *rxq;
+ struct omap_mbox_queue *rxq;
struct device *dev;
struct omap_mbox_device *parent;
struct omap_mbox_fifo tx_fifo;
struct omap_mbox_fifo rx_fifo;
u32 ctx[OMAP4_MBOX_NR_REGS];
u32 intr_type;
- int use_count;
- struct blocking_notifier_head notifier;
+ struct mbox_chan *chan;
};
/* global variables for the mailbox devices */
@@ -129,6 +129,14 @@
module_param(mbox_kfifo_size, uint, S_IRUGO);
MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)");
+static struct omap_mbox *mbox_chan_to_omap_mbox(struct mbox_chan *chan)
+{
+ if (!chan || !chan->con_priv)
+ return NULL;
+
+ return (struct omap_mbox *)chan->con_priv;
+}
+
static inline
unsigned int mbox_read_reg(struct omap_mbox_device *mdev, size_t ofs)
{
@@ -194,41 +202,14 @@
return (int)(enable & status & bit);
}
-/*
- * message sender
- */
-int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t 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_fifo_full(mbox)) {
- mbox_fifo_write(mbox, msg);
- goto out;
- }
-
- len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
- WARN_ON(len != sizeof(msg));
-
- tasklet_schedule(&mbox->txq->tasklet);
-
-out:
- spin_unlock_bh(&mq->lock);
- return ret;
-}
-EXPORT_SYMBOL(omap_mbox_msg_send);
-
-void omap_mbox_save_ctx(struct omap_mbox *mbox)
+void omap_mbox_save_ctx(struct mbox_chan *chan)
{
int i;
int nr_regs;
+ struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
+
+ if (WARN_ON(!mbox))
+ return;
if (mbox->intr_type)
nr_regs = OMAP4_MBOX_NR_REGS;
@@ -243,10 +224,14 @@
}
EXPORT_SYMBOL(omap_mbox_save_ctx);
-void omap_mbox_restore_ctx(struct omap_mbox *mbox)
+void omap_mbox_restore_ctx(struct mbox_chan *chan)
{
int i;
int nr_regs;
+ struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
+
+ if (WARN_ON(!mbox))
+ return;
if (mbox->intr_type)
nr_regs = OMAP4_MBOX_NR_REGS;
@@ -254,14 +239,13 @@
nr_regs = MBOX_NR_REGS;
for (i = 0; i < nr_regs; i++) {
mbox_write_reg(mbox->parent, mbox->ctx[i], i * sizeof(u32));
-
dev_dbg(mbox->dev, "%s: [%02x] %08x\n", __func__,
i, mbox->ctx[i]);
}
}
EXPORT_SYMBOL(omap_mbox_restore_ctx);
-void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+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) ?
@@ -273,9 +257,8 @@
l |= bit;
mbox_write_reg(mbox->parent, l, irqenable);
}
-EXPORT_SYMBOL(omap_mbox_enable_irq);
-void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+static void _omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
{
struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
&mbox->tx_fifo : &mbox->rx_fifo;
@@ -291,28 +274,28 @@
mbox_write_reg(mbox->parent, bit, irqdisable);
}
-EXPORT_SYMBOL(omap_mbox_disable_irq);
-static void mbox_tx_tasklet(unsigned long tx_data)
+void omap_mbox_enable_irq(struct mbox_chan *chan, 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 *mbox = mbox_chan_to_omap_mbox(chan);
- while (kfifo_len(&mq->fifo)) {
- if (mbox_fifo_full(mbox)) {
- omap_mbox_enable_irq(mbox, IRQ_TX);
- break;
- }
+ if (WARN_ON(!mbox))
+ return;
- ret = kfifo_out(&mq->fifo, (unsigned char *)&msg,
- sizeof(msg));
- WARN_ON(ret != sizeof(msg));
-
- mbox_fifo_write(mbox, msg);
- }
+ _omap_mbox_enable_irq(mbox, irq);
}
+EXPORT_SYMBOL(omap_mbox_enable_irq);
+
+void omap_mbox_disable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq)
+{
+ struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
+
+ if (WARN_ON(!mbox))
+ return;
+
+ _omap_mbox_disable_irq(mbox, irq);
+}
+EXPORT_SYMBOL(omap_mbox_disable_irq);
/*
* Message receiver(workqueue)
@@ -328,12 +311,11 @@
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);
+ mbox_chan_received_data(mq->mbox->chan, (void *)msg);
spin_lock_irq(&mq->lock);
if (mq->full) {
mq->full = false;
- omap_mbox_enable_irq(mq->mbox, IRQ_RX);
+ _omap_mbox_enable_irq(mq->mbox, IRQ_RX);
}
spin_unlock_irq(&mq->lock);
}
@@ -344,9 +326,9 @@
*/
static void __mbox_tx_interrupt(struct omap_mbox *mbox)
{
- omap_mbox_disable_irq(mbox, IRQ_TX);
+ _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)
@@ -357,7 +339,7 @@
while (!mbox_fifo_empty(mbox)) {
if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
- omap_mbox_disable_irq(mbox, IRQ_RX);
+ _omap_mbox_disable_irq(mbox, IRQ_RX);
mq->full = true;
goto nomem;
}
@@ -388,11 +370,13 @@
}
static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
- void (*work) (struct work_struct *),
- void (*tasklet)(unsigned long))
+ void (*work)(struct work_struct *))
{
struct omap_mbox_queue *mq;
+ if (!work)
+ return NULL;
+
mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
if (!mq)
return NULL;
@@ -402,12 +386,9 @@
if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
goto error;
- if (work)
- INIT_WORK(&mq->work, work);
-
- if (tasklet)
- tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox);
+ INIT_WORK(&mq->work, work);
return mq;
+
error:
kfree(mq);
return NULL;
@@ -423,71 +404,35 @@
{
int ret = 0;
struct omap_mbox_queue *mq;
- struct omap_mbox_device *mdev = mbox->parent;
- mutex_lock(&mdev->cfg_lock);
- ret = pm_runtime_get_sync(mdev->dev);
- if (unlikely(ret < 0))
- goto fail_startup;
+ mq = mbox_queue_alloc(mbox, mbox_rx_work);
+ if (!mq)
+ return -ENOMEM;
+ mbox->rxq = mq;
+ mq->mbox = mbox;
- if (!mbox->use_count++) {
- mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet);
- if (!mq) {
- ret = -ENOMEM;
- goto fail_alloc_txq;
- }
- mbox->txq = mq;
-
- 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;
- }
-
- omap_mbox_enable_irq(mbox, IRQ_RX);
+ 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;
}
- mutex_unlock(&mdev->cfg_lock);
+
+ _omap_mbox_enable_irq(mbox, IRQ_RX);
+
return 0;
fail_request_irq:
mbox_queue_free(mbox->rxq);
-fail_alloc_rxq:
- mbox_queue_free(mbox->txq);
-fail_alloc_txq:
- pm_runtime_put_sync(mdev->dev);
- mbox->use_count--;
-fail_startup:
- mutex_unlock(&mdev->cfg_lock);
return ret;
}
static void omap_mbox_fini(struct omap_mbox *mbox)
{
- struct omap_mbox_device *mdev = mbox->parent;
-
- mutex_lock(&mdev->cfg_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);
- }
-
- pm_runtime_put_sync(mdev->dev);
-
- mutex_unlock(&mdev->cfg_lock);
+ _omap_mbox_disable_irq(mbox, IRQ_RX);
+ free_irq(mbox->irq, mbox);
+ flush_work(&mbox->rxq->work);
+ mbox_queue_free(mbox->rxq);
}
static struct omap_mbox *omap_mbox_device_find(struct omap_mbox_device *mdev,
@@ -509,42 +454,55 @@
return mbox;
}
-struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb)
+struct mbox_chan *omap_mbox_request_channel(struct mbox_client *cl,
+ const char *chan_name)
{
+ struct device *dev = cl->dev;
struct omap_mbox *mbox = NULL;
struct omap_mbox_device *mdev;
+ struct mbox_chan *chan;
+ unsigned long flags;
int ret;
+ if (!dev)
+ return ERR_PTR(-ENODEV);
+
+ if (dev->of_node) {
+ pr_err("%s: please use mbox_request_channel(), this API is supported only for OMAP non-DT usage\n",
+ __func__);
+ return ERR_PTR(-ENODEV);
+ }
+
mutex_lock(&omap_mbox_devices_lock);
list_for_each_entry(mdev, &omap_mbox_devices, elem) {
- mbox = omap_mbox_device_find(mdev, name);
+ mbox = omap_mbox_device_find(mdev, chan_name);
if (mbox)
break;
}
mutex_unlock(&omap_mbox_devices_lock);
- if (!mbox)
+ if (!mbox || !mbox->chan)
return ERR_PTR(-ENOENT);
- if (nb)
- blocking_notifier_chain_register(&mbox->notifier, nb);
+ chan = mbox->chan;
+ spin_lock_irqsave(&chan->lock, flags);
+ chan->msg_free = 0;
+ chan->msg_count = 0;
+ chan->active_req = NULL;
+ chan->cl = cl;
+ init_completion(&chan->tx_complete);
+ spin_unlock_irqrestore(&chan->lock, flags);
- ret = omap_mbox_startup(mbox);
+ ret = chan->mbox->ops->startup(chan);
if (ret) {
- blocking_notifier_chain_unregister(&mbox->notifier, nb);
- return ERR_PTR(-ENODEV);
+ pr_err("Unable to startup the chan (%d)\n", ret);
+ mbox_free_channel(chan);
+ chan = ERR_PTR(ret);
}
- return mbox;
+ return chan;
}
-EXPORT_SYMBOL(omap_mbox_get);
-
-void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb)
-{
- blocking_notifier_chain_unregister(&mbox->notifier, nb);
- omap_mbox_fini(mbox);
-}
-EXPORT_SYMBOL(omap_mbox_put);
+EXPORT_SYMBOL(omap_mbox_request_channel);
static struct class omap_mbox_class = { .name = "mbox", };
@@ -560,25 +518,25 @@
mboxes = mdev->mboxes;
for (i = 0; mboxes[i]; i++) {
struct omap_mbox *mbox = mboxes[i];
- mbox->dev = device_create(&omap_mbox_class,
- mdev->dev, 0, mbox, "%s", mbox->name);
+ mbox->dev = device_create(&omap_mbox_class, mdev->dev,
+ 0, mbox, "%s", mbox->name);
if (IS_ERR(mbox->dev)) {
ret = PTR_ERR(mbox->dev);
goto err_out;
}
-
- BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier);
}
mutex_lock(&omap_mbox_devices_lock);
list_add(&mdev->elem, &omap_mbox_devices);
mutex_unlock(&omap_mbox_devices_lock);
- return 0;
+ ret = mbox_controller_register(&mdev->controller);
err_out:
- while (i--)
- device_unregister(mboxes[i]->dev);
+ if (ret) {
+ while (i--)
+ device_unregister(mboxes[i]->dev);
+ }
return ret;
}
@@ -594,12 +552,64 @@
list_del(&mdev->elem);
mutex_unlock(&omap_mbox_devices_lock);
+ mbox_controller_unregister(&mdev->controller);
+
mboxes = mdev->mboxes;
for (i = 0; mboxes[i]; i++)
device_unregister(mboxes[i]->dev);
return 0;
}
+static int omap_mbox_chan_startup(struct mbox_chan *chan)
+{
+ struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
+ struct omap_mbox_device *mdev = mbox->parent;
+ int ret = 0;
+
+ 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;
+}
+
+static void omap_mbox_chan_shutdown(struct mbox_chan *chan)
+{
+ struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
+ struct omap_mbox_device *mdev = mbox->parent;
+
+ mutex_lock(&mdev->cfg_lock);
+ omap_mbox_fini(mbox);
+ pm_runtime_put_sync(mdev->dev);
+ mutex_unlock(&mdev->cfg_lock);
+}
+
+static int omap_mbox_chan_send_data(struct mbox_chan *chan, void *data)
+{
+ struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
+ int ret = -EBUSY;
+
+ if (!mbox)
+ return -EINVAL;
+
+ if (!mbox_fifo_full(mbox)) {
+ mbox_fifo_write(mbox, (mbox_msg_t)data);
+ ret = 0;
+ }
+
+ /* always enable the interrupt */
+ _omap_mbox_enable_irq(mbox, IRQ_TX);
+ return ret;
+}
+
+static 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,
+};
+
static const struct of_device_id omap_mailbox_of_match[] = {
{
.compatible = "ti,omap2-mailbox",
@@ -619,10 +629,35 @@
};
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)
+{
+ phandle phandle = sp->args[0];
+ struct device_node *node;
+ struct omap_mbox_device *mdev;
+ struct omap_mbox *mbox;
+
+ mdev = container_of(controller, struct omap_mbox_device, controller);
+ if (WARN_ON(!mdev))
+ return NULL;
+
+ node = of_find_node_by_phandle(phandle);
+ if (!node) {
+ pr_err("%s: could not find node phandle 0x%x\n",
+ __func__, phandle);
+ return NULL;
+ }
+
+ mbox = omap_mbox_device_find(mdev, node->name);
+ of_node_put(node);
+ return mbox ? mbox->chan : NULL;
+}
+
static int omap_mbox_probe(struct platform_device *pdev)
{
struct resource *mem;
int ret;
+ struct mbox_chan *chnls;
struct omap_mbox **list, *mbox, *mboxblk;
struct omap_mbox_pdata *pdata = pdev->dev.platform_data;
struct omap_mbox_dev_info *info = NULL;
@@ -727,6 +762,11 @@
if (!list)
return -ENOMEM;
+ chnls = devm_kzalloc(&pdev->dev, (info_count + 1) * sizeof(*chnls),
+ GFP_KERNEL);
+ if (!chnls)
+ return -ENOMEM;
+
mboxblk = devm_kzalloc(&pdev->dev, info_count * sizeof(*mbox),
GFP_KERNEL);
if (!mboxblk)
@@ -758,6 +798,8 @@
mbox->irq = platform_get_irq(pdev, finfo->tx_irq);
if (mbox->irq < 0)
return mbox->irq;
+ mbox->chan = &chnls[i];
+ chnls[i].con_priv = mbox;
list[i] = mbox++;
}
@@ -766,6 +808,14 @@
mdev->num_users = num_users;
mdev->num_fifos = num_fifos;
mdev->mboxes = list;
+
+ /* OMAP does not have a Tx-Done IRQ, but rather a Tx-Ready IRQ */
+ mdev->controller.txdone_irq = true;
+ mdev->controller.dev = mdev->dev;
+ mdev->controller.ops = &omap_mbox_chan_ops;
+ mdev->controller.chans = chnls;
+ mdev->controller.num_chans = info_count;
+ mdev->controller.of_xlate = omap_mbox_of_xlate;
ret = omap_mbox_register(mdev);
if (ret)
return ret;