linux/arch/arm/plat-omap/mailbox.c
Tejun Heo 43829731dd workqueue: deprecate flush[_delayed]_work_sync()
flush[_delayed]_work_sync() are now spurious.  Mark them deprecated
and convert all users to flush[_delayed]_work().

If you're cc'd and wondering what's going on: Now all workqueues are
non-reentrant and the regular flushes guarantee that the work item is
not pending or running on any CPU on return, so there's no reason to
use the sync flushes at all and they're going away.

This patch doesn't make any functional difference.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Mattia Dongili <malattia@linux.it>
Cc: Kent Yoder <key@linux.vnet.ibm.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: Bryan Wu <bryan.wu@canonical.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-wireless@vger.kernel.org
Cc: Anton Vorontsov <cbou@mail.ru>
Cc: Sangbeom Kim <sbkim73@samsung.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Petr Vandrovec <petr@vandrovec.name>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Avi Kivity <avi@redhat.com>
2012-08-20 14:51:24 -07:00

436 lines
9.3 KiB
C

/*
* OMAP mailbox driver
*
* Copyright (C) 2006-2009 Nokia Corporation. All rights reserved.
*
* 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
*
*/
#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 <plat/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");