[PATCH 2/2] mailbox: OMAP: introduce mailbox framework
From: Omar Ramirez Luna
Date: Mon Oct 29 2012 - 13:06:32 EST
Actually moving it from plat-omap code as this is supposed to be
under drivers/ folder. This framework should work with the current
OMAP processors that have mailbox and can be used as a method of
interprocessor communication.
Signed-off-by: Omar Ramirez Luna <omar.luna@xxxxxxxxxx>
---
arch/arm/plat-omap/Kconfig | 16 --
arch/arm/plat-omap/Makefile | 3 -
arch/arm/plat-omap/mailbox.c | 435 ------------------------------------------
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/mailbox/Kconfig | 28 +++
drivers/mailbox/Makefile | 1 +
drivers/mailbox/mailbox.c | 435 ++++++++++++++++++++++++++++++++++++++++++
8 files changed, 467 insertions(+), 454 deletions(-)
delete mode 100644 arch/arm/plat-omap/mailbox.c
create mode 100644 drivers/mailbox/Kconfig
create mode 100644 drivers/mailbox/Makefile
create mode 100644 drivers/mailbox/mailbox.c
diff --git a/arch/arm/plat-omap/Kconfig b/arch/arm/plat-omap/Kconfig
index 82fcb20..419648f 100644
--- a/arch/arm/plat-omap/Kconfig
+++ b/arch/arm/plat-omap/Kconfig
@@ -116,22 +116,6 @@ config OMAP_MUX_WARNINGS
to change the pin multiplexing setup. When there are no warnings
printed, it's safe to deselect OMAP_MUX for your product.
-config OMAP_MBOX_FWK
- tristate "Mailbox framework support"
- depends on ARCH_OMAP
- help
- Say Y here if you want to use OMAP Mailbox framework support for
- DSP, IVA1.0 and IVA2 in OMAP1/2/3.
-
-config OMAP_MBOX_KFIFO_SIZE
- int "Mailbox kfifo default buffer size (bytes)"
- depends on OMAP_MBOX_FWK
- default 256
- help
- Specify the default size of mailbox's kfifo buffers (bytes).
- This can also be changed at runtime (via the mbox_kfifo_size
- module parameter).
-
config OMAP_IOMMU_IVA2
bool
diff --git a/arch/arm/plat-omap/Makefile b/arch/arm/plat-omap/Makefile
index 4bd0ace..4702d1f 100644
--- a/arch/arm/plat-omap/Makefile
+++ b/arch/arm/plat-omap/Makefile
@@ -16,7 +16,4 @@ obj-$(CONFIG_OMAP_DEBUG_LEDS) += debug-leds.o
i2c-omap-$(CONFIG_I2C_OMAP) := i2c.o
obj-y += $(i2c-omap-m) $(i2c-omap-y)
-# OMAP mailbox framework
-obj-$(CONFIG_OMAP_MBOX_FWK) += mailbox.o
-
obj-$(CONFIG_OMAP_PM_NOOP) += omap-pm-noop.o
diff --git a/arch/arm/plat-omap/mailbox.c b/arch/arm/plat-omap/mailbox.c
deleted file mode 100644
index cae8692..0000000
--- a/arch/arm/plat-omap/mailbox.c
+++ /dev/null
@@ -1,435 +0,0 @@
-/*
- * OMAP mailbox driver
- *
- * Copyright (C) 2006-2009 Nokia Corporation. All rights reserved.
- *
- * Contact: Hiroshi DOYU <Hiroshi.DOYU@xxxxxxxxx>
- *
- * 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/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/module.h>
-
-#include <linux/platform_data/omap_mailbox.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)
-{
- return mbox->ops->fifo_full(mbox);
-}
-
-/* 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)
-{
- return mbox->ops->is_irq(mbox, irq);
-}
-
-/*
- * message sender
- */
-static int __mbox_poll_for_space(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;
-}
-
-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_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));
-
- tasklet_schedule(&mbox->txq->tasklet);
-
-out:
- spin_unlock_bh(&mq->lock);
- return ret;
-}
-EXPORT_SYMBOL(omap_mbox_msg_send);
-
-static void mbox_tx_tasklet(unsigned long tx_data)
-{
- struct omap_mbox *mbox = (struct omap_mbox *)tx_data;
- struct omap_mbox_queue *mq = mbox->txq;
- mbox_msg_t msg;
- int ret;
-
- while (kfifo_len(&mq->fifo)) {
- if (__mbox_poll_for_space(mbox)) {
- omap_mbox_enable_irq(mbox, IRQ_TX);
- break;
- }
-
- ret = kfifo_out(&mq->fifo, (unsigned char *)&msg,
- sizeof(msg));
- WARN_ON(ret != sizeof(msg));
-
- mbox_fifo_write(mbox, msg);
- }
-}
-
-/*
- * Message receiver(workqueue)
- */
-static void mbox_rx_work(struct work_struct *work)
-{
- 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);
- }
-}
-
-/*
- * Mailbox interrupt handler
- */
-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);
-}
-
-static void __mbox_rx_interrupt(struct omap_mbox *mbox)
-{
- struct omap_mbox_queue *mq = mbox->rxq;
- mbox_msg_t msg;
- int len;
-
- 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;
- }
-
- /* no more messages in the fifo. clear IRQ source. */
- ack_mbox_irq(mbox, IRQ_RX);
-nomem:
- schedule_work(&mbox->rxq->work);
-}
-
-static irqreturn_t mbox_interrupt(int irq, void *p)
-{
- struct omap_mbox *mbox = p;
-
- if (is_mbox_irq(mbox, IRQ_TX))
- __mbox_tx_interrupt(mbox);
-
- if (is_mbox_irq(mbox, IRQ_RX))
- __mbox_rx_interrupt(mbox);
-
- return IRQ_HANDLED;
-}
-
-static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
- void (*work) (struct work_struct *),
- void (*tasklet)(unsigned long))
-{
- struct omap_mbox_queue *mq;
-
- mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
- if (!mq)
- return NULL;
-
- spin_lock_init(&mq->lock);
-
- 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);
- return mq;
-error:
- kfree(mq);
- return NULL;
-}
-
-static void mbox_queue_free(struct omap_mbox_queue *q)
-{
- kfifo_free(&q->fifo);
- kfree(q);
-}
-
-static int omap_mbox_startup(struct omap_mbox *mbox)
-{
- 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++) {
- 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;
- }
- 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;
-
- omap_mbox_enable_irq(mbox, IRQ_RX);
- }
- mutex_unlock(&mbox_configured_lock);
- return 0;
-
-fail_alloc_rxq:
- mbox_queue_free(mbox->txq);
-fail_alloc_txq:
- free_irq(mbox->irq, mbox);
-fail_request_irq:
- if (mbox->ops->shutdown)
- mbox->ops->shutdown(mbox);
- mbox->use_count--;
-fail_startup:
- mbox_configured--;
- mutex_unlock(&mbox_configured_lock);
- return ret;
-}
-
-static void omap_mbox_fini(struct omap_mbox *mbox)
-{
- 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 (likely(mbox->ops->shutdown)) {
- if (!--mbox_configured)
- mbox->ops->shutdown(mbox);
- }
-
- mutex_unlock(&mbox_configured_lock);
-}
-
-struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb)
-{
- struct omap_mbox *_mbox, *mbox = NULL;
- int i, ret;
-
- if (!mboxes)
- return ERR_PTR(-EINVAL);
-
- for (i = 0; (_mbox = mboxes[i]); i++) {
- if (!strcmp(_mbox->name, name)) {
- mbox = _mbox;
- break;
- }
- }
-
- if (!mbox)
- return ERR_PTR(-ENOENT);
-
- if (nb)
- blocking_notifier_chain_register(&mbox->notifier, nb);
-
- ret = omap_mbox_startup(mbox);
- if (ret) {
- blocking_notifier_chain_unregister(&mbox->notifier, nb);
- return ERR_PTR(-ENODEV);
- }
-
- return mbox;
-}
-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);
-
-static struct class omap_mbox_class = { .name = "mbox", };
-
-int omap_mbox_register(struct device *parent, struct omap_mbox **list)
-{
- int ret;
- int i;
-
- mboxes = list;
- if (!mboxes)
- return -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;
- }
-
- BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier);
- }
- return 0;
-
-err_out:
- while (i--)
- device_unregister(mboxes[i]->dev);
- return ret;
-}
-EXPORT_SYMBOL(omap_mbox_register);
-
-int omap_mbox_unregister(void)
-{
- int i;
-
- if (!mboxes)
- return -EINVAL;
-
- for (i = 0; mboxes[i]; i++)
- device_unregister(mboxes[i]->dev);
- mboxes = NULL;
- return 0;
-}
-EXPORT_SYMBOL(omap_mbox_unregister);
-
-static int __init omap_mbox_init(void)
-{
- int err;
-
- err = class_register(&omap_mbox_class);
- if (err)
- return err;
-
- /* 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));
-
- return 0;
-}
-subsys_initcall(omap_mbox_init);
-
-static void __exit omap_mbox_exit(void)
-{
- class_unregister(&omap_mbox_class);
-}
-module_exit(omap_mbox_exit);
-
-MODULE_LICENSE("GPL v2");
-MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
-MODULE_AUTHOR("Toshihiro Kobayashi");
-MODULE_AUTHOR("Hiroshi DOYU");
diff --git a/drivers/Kconfig b/drivers/Kconfig
index dbdefa3..7a4fb98 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -134,6 +134,8 @@ source "drivers/hwspinlock/Kconfig"
source "drivers/clocksource/Kconfig"
+source "drivers/mailbox/Kconfig"
+
source "drivers/iommu/Kconfig"
source "drivers/remoteproc/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index a16a8d0..78f2bf0 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -132,6 +132,7 @@ obj-y += clk/
obj-$(CONFIG_HWSPINLOCK) += hwspinlock/
obj-$(CONFIG_NFC) += nfc/
+obj-$(CONFIG_MAILBOX) += mailbox/
obj-$(CONFIG_IOMMU_SUPPORT) += iommu/
obj-$(CONFIG_REMOTEPROC) += remoteproc/
obj-$(CONFIG_RPMSG) += rpmsg/
diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
new file mode 100644
index 0000000..937b887
--- /dev/null
+++ b/drivers/mailbox/Kconfig
@@ -0,0 +1,28 @@
+menuconfig MAILBOX
+ bool "Mailbox Hardware Support"
+ help
+ Mailbox is a framework to control hardware communication between
+ on-chip processors through queued messages and interrupt driven
+ signals. Say Y if your platform supports hardware mailboxes.
+
+if MAILBOX
+
+config OMAP_MBOX_FWK
+ tristate "OMAP Mailbox framework support"
+ depends on ARCH_OMAP
+ help
+ Mailbox implementation for OMAP family chips with hardware for
+ interprocessor communication involving DSP, IVA1.0 and IVA2 in
+ OMAP1/2/3; or IPU, IVA HD and DSP in OMAP4. Say Y here if you
+ want to use OMAP Mailbox framework support.
+
+config OMAP_MBOX_KFIFO_SIZE
+ int "Mailbox kfifo default buffer size (bytes)"
+ depends on OMAP_MBOX_FWK
+ default 256
+ help
+ Specify the default size of mailbox's kfifo buffers (bytes).
+ This can also be changed at runtime (via the mbox_kfifo_size
+ module parameter).
+
+endif
diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
new file mode 100644
index 0000000..1040ac5
--- /dev/null
+++ b/drivers/mailbox/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_OMAP_MBOX_FWK) += mailbox.o
diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
new file mode 100644
index 0000000..cae8692
--- /dev/null
+++ b/drivers/mailbox/mailbox.c
@@ -0,0 +1,435 @@
+/*
+ * OMAP mailbox driver
+ *
+ * Copyright (C) 2006-2009 Nokia Corporation. All rights reserved.
+ *
+ * Contact: Hiroshi DOYU <Hiroshi.DOYU@xxxxxxxxx>
+ *
+ * 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/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/module.h>
+
+#include <linux/platform_data/omap_mailbox.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)
+{
+ return mbox->ops->fifo_full(mbox);
+}
+
+/* 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)
+{
+ return mbox->ops->is_irq(mbox, irq);
+}
+
+/*
+ * message sender
+ */
+static int __mbox_poll_for_space(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;
+}
+
+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_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));
+
+ tasklet_schedule(&mbox->txq->tasklet);
+
+out:
+ spin_unlock_bh(&mq->lock);
+ return ret;
+}
+EXPORT_SYMBOL(omap_mbox_msg_send);
+
+static void mbox_tx_tasklet(unsigned long tx_data)
+{
+ struct omap_mbox *mbox = (struct omap_mbox *)tx_data;
+ struct omap_mbox_queue *mq = mbox->txq;
+ mbox_msg_t msg;
+ int ret;
+
+ while (kfifo_len(&mq->fifo)) {
+ if (__mbox_poll_for_space(mbox)) {
+ omap_mbox_enable_irq(mbox, IRQ_TX);
+ break;
+ }
+
+ ret = kfifo_out(&mq->fifo, (unsigned char *)&msg,
+ sizeof(msg));
+ WARN_ON(ret != sizeof(msg));
+
+ mbox_fifo_write(mbox, msg);
+ }
+}
+
+/*
+ * Message receiver(workqueue)
+ */
+static void mbox_rx_work(struct work_struct *work)
+{
+ 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);
+ }
+}
+
+/*
+ * Mailbox interrupt handler
+ */
+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);
+}
+
+static void __mbox_rx_interrupt(struct omap_mbox *mbox)
+{
+ struct omap_mbox_queue *mq = mbox->rxq;
+ mbox_msg_t msg;
+ int len;
+
+ 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;
+ }
+
+ /* no more messages in the fifo. clear IRQ source. */
+ ack_mbox_irq(mbox, IRQ_RX);
+nomem:
+ schedule_work(&mbox->rxq->work);
+}
+
+static irqreturn_t mbox_interrupt(int irq, void *p)
+{
+ struct omap_mbox *mbox = p;
+
+ if (is_mbox_irq(mbox, IRQ_TX))
+ __mbox_tx_interrupt(mbox);
+
+ if (is_mbox_irq(mbox, IRQ_RX))
+ __mbox_rx_interrupt(mbox);
+
+ return IRQ_HANDLED;
+}
+
+static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
+ void (*work) (struct work_struct *),
+ void (*tasklet)(unsigned long))
+{
+ struct omap_mbox_queue *mq;
+
+ mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
+ if (!mq)
+ return NULL;
+
+ spin_lock_init(&mq->lock);
+
+ 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);
+ return mq;
+error:
+ kfree(mq);
+ return NULL;
+}
+
+static void mbox_queue_free(struct omap_mbox_queue *q)
+{
+ kfifo_free(&q->fifo);
+ kfree(q);
+}
+
+static int omap_mbox_startup(struct omap_mbox *mbox)
+{
+ 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++) {
+ 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;
+ }
+ 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;
+
+ omap_mbox_enable_irq(mbox, IRQ_RX);
+ }
+ mutex_unlock(&mbox_configured_lock);
+ return 0;
+
+fail_alloc_rxq:
+ mbox_queue_free(mbox->txq);
+fail_alloc_txq:
+ free_irq(mbox->irq, mbox);
+fail_request_irq:
+ if (mbox->ops->shutdown)
+ mbox->ops->shutdown(mbox);
+ mbox->use_count--;
+fail_startup:
+ mbox_configured--;
+ mutex_unlock(&mbox_configured_lock);
+ return ret;
+}
+
+static void omap_mbox_fini(struct omap_mbox *mbox)
+{
+ 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 (likely(mbox->ops->shutdown)) {
+ if (!--mbox_configured)
+ mbox->ops->shutdown(mbox);
+ }
+
+ mutex_unlock(&mbox_configured_lock);
+}
+
+struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb)
+{
+ struct omap_mbox *_mbox, *mbox = NULL;
+ int i, ret;
+
+ if (!mboxes)
+ return ERR_PTR(-EINVAL);
+
+ for (i = 0; (_mbox = mboxes[i]); i++) {
+ if (!strcmp(_mbox->name, name)) {
+ mbox = _mbox;
+ break;
+ }
+ }
+
+ if (!mbox)
+ return ERR_PTR(-ENOENT);
+
+ if (nb)
+ blocking_notifier_chain_register(&mbox->notifier, nb);
+
+ ret = omap_mbox_startup(mbox);
+ if (ret) {
+ blocking_notifier_chain_unregister(&mbox->notifier, nb);
+ return ERR_PTR(-ENODEV);
+ }
+
+ return mbox;
+}
+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);
+
+static struct class omap_mbox_class = { .name = "mbox", };
+
+int omap_mbox_register(struct device *parent, struct omap_mbox **list)
+{
+ int ret;
+ int i;
+
+ mboxes = list;
+ if (!mboxes)
+ return -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;
+ }
+
+ BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier);
+ }
+ return 0;
+
+err_out:
+ while (i--)
+ device_unregister(mboxes[i]->dev);
+ return ret;
+}
+EXPORT_SYMBOL(omap_mbox_register);
+
+int omap_mbox_unregister(void)
+{
+ int i;
+
+ if (!mboxes)
+ return -EINVAL;
+
+ for (i = 0; mboxes[i]; i++)
+ device_unregister(mboxes[i]->dev);
+ mboxes = NULL;
+ return 0;
+}
+EXPORT_SYMBOL(omap_mbox_unregister);
+
+static int __init omap_mbox_init(void)
+{
+ int err;
+
+ err = class_register(&omap_mbox_class);
+ if (err)
+ return err;
+
+ /* 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));
+
+ return 0;
+}
+subsys_initcall(omap_mbox_init);
+
+static void __exit omap_mbox_exit(void)
+{
+ class_unregister(&omap_mbox_class);
+}
+module_exit(omap_mbox_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
+MODULE_AUTHOR("Toshihiro Kobayashi");
+MODULE_AUTHOR("Hiroshi DOYU");
--
1.7.9.5
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