mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 19:29:37 +00:00
![Javier Martinez Canillas](/assets/img/avatar_default.png)
If the driver is built as a module, autoload won't work because the module alias information is not filled. So user-space can't match the registered device with the corresponding module. Export the module alias information using the MODULE_DEVICE_TABLE() macro. Before this patch: $ modinfo drivers/mailbox/mailbox-sti.ko | grep alias alias: platform:mailbox-sti After this patch: $ modinfo drivers/mailbox/mailbox-sti.ko | grep alias alias: platform:mailbox-sti alias: of:N*T*Cst,stih407-mailboxC* alias: of:N*T*Cst,stih407-mailbox Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Acked-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
514 lines
13 KiB
C
514 lines
13 KiB
C
/*
|
|
* STi Mailbox
|
|
*
|
|
* Copyright (C) 2015 ST Microelectronics
|
|
*
|
|
* Author: Lee Jones <lee.jones@linaro.org> for ST Microelectronics
|
|
*
|
|
* Based on the original driver written by;
|
|
* Alexandre Torgue, Olivier Lebreton and Loic Pallardy
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*/
|
|
|
|
#include <linux/err.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/io.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/mailbox_controller.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_device.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/slab.h>
|
|
|
|
#include "mailbox.h"
|
|
|
|
#define STI_MBOX_INST_MAX 4 /* RAM saving: Max supported instances */
|
|
#define STI_MBOX_CHAN_MAX 20 /* RAM saving: Max supported channels */
|
|
|
|
#define STI_IRQ_VAL_OFFSET 0x04 /* Read interrupt status */
|
|
#define STI_IRQ_SET_OFFSET 0x24 /* Generate a Tx channel interrupt */
|
|
#define STI_IRQ_CLR_OFFSET 0x44 /* Clear pending Rx interrupts */
|
|
#define STI_ENA_VAL_OFFSET 0x64 /* Read enable status */
|
|
#define STI_ENA_SET_OFFSET 0x84 /* Enable a channel */
|
|
#define STI_ENA_CLR_OFFSET 0xa4 /* Disable a channel */
|
|
|
|
#define MBOX_BASE(mdev, inst) ((mdev)->base + ((inst) * 4))
|
|
|
|
/**
|
|
* STi Mailbox device data
|
|
*
|
|
* An IP Mailbox is currently composed of 4 instances
|
|
* Each instance is currently composed of 32 channels
|
|
* This means that we have 128 channels per Mailbox
|
|
* A channel an be used for TX or RX
|
|
*
|
|
* @dev: Device to which it is attached
|
|
* @mbox: Representation of a communication channel controller
|
|
* @base: Base address of the register mapping region
|
|
* @name: Name of the mailbox
|
|
* @enabled: Local copy of enabled channels
|
|
* @lock: Mutex protecting enabled status
|
|
*/
|
|
struct sti_mbox_device {
|
|
struct device *dev;
|
|
struct mbox_controller *mbox;
|
|
void __iomem *base;
|
|
const char *name;
|
|
u32 enabled[STI_MBOX_INST_MAX];
|
|
spinlock_t lock;
|
|
};
|
|
|
|
/**
|
|
* STi Mailbox platform specific configuration
|
|
*
|
|
* @num_inst: Maximum number of instances in one HW Mailbox
|
|
* @num_chan: Maximum number of channel per instance
|
|
*/
|
|
struct sti_mbox_pdata {
|
|
unsigned int num_inst;
|
|
unsigned int num_chan;
|
|
};
|
|
|
|
/**
|
|
* STi Mailbox allocated channel information
|
|
*
|
|
* @mdev: Pointer to parent Mailbox device
|
|
* @instance: Instance number channel resides in
|
|
* @channel: Channel number pertaining to this container
|
|
*/
|
|
struct sti_channel {
|
|
struct sti_mbox_device *mdev;
|
|
unsigned int instance;
|
|
unsigned int channel;
|
|
};
|
|
|
|
static inline bool sti_mbox_channel_is_enabled(struct mbox_chan *chan)
|
|
{
|
|
struct sti_channel *chan_info = chan->con_priv;
|
|
struct sti_mbox_device *mdev = chan_info->mdev;
|
|
unsigned int instance = chan_info->instance;
|
|
unsigned int channel = chan_info->channel;
|
|
|
|
return mdev->enabled[instance] & BIT(channel);
|
|
}
|
|
|
|
static inline
|
|
struct mbox_chan *sti_mbox_to_channel(struct mbox_controller *mbox,
|
|
unsigned int instance,
|
|
unsigned int channel)
|
|
{
|
|
struct sti_channel *chan_info;
|
|
int i;
|
|
|
|
for (i = 0; i < mbox->num_chans; i++) {
|
|
chan_info = mbox->chans[i].con_priv;
|
|
if (chan_info &&
|
|
chan_info->instance == instance &&
|
|
chan_info->channel == channel)
|
|
return &mbox->chans[i];
|
|
}
|
|
|
|
dev_err(mbox->dev,
|
|
"Channel not registered: instance: %d channel: %d\n",
|
|
instance, channel);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void sti_mbox_enable_channel(struct mbox_chan *chan)
|
|
{
|
|
struct sti_channel *chan_info = chan->con_priv;
|
|
struct sti_mbox_device *mdev = chan_info->mdev;
|
|
unsigned int instance = chan_info->instance;
|
|
unsigned int channel = chan_info->channel;
|
|
unsigned long flags;
|
|
void __iomem *base = MBOX_BASE(mdev, instance);
|
|
|
|
spin_lock_irqsave(&mdev->lock, flags);
|
|
mdev->enabled[instance] |= BIT(channel);
|
|
writel_relaxed(BIT(channel), base + STI_ENA_SET_OFFSET);
|
|
spin_unlock_irqrestore(&mdev->lock, flags);
|
|
}
|
|
|
|
static void sti_mbox_disable_channel(struct mbox_chan *chan)
|
|
{
|
|
struct sti_channel *chan_info = chan->con_priv;
|
|
struct sti_mbox_device *mdev = chan_info->mdev;
|
|
unsigned int instance = chan_info->instance;
|
|
unsigned int channel = chan_info->channel;
|
|
unsigned long flags;
|
|
void __iomem *base = MBOX_BASE(mdev, instance);
|
|
|
|
spin_lock_irqsave(&mdev->lock, flags);
|
|
mdev->enabled[instance] &= ~BIT(channel);
|
|
writel_relaxed(BIT(channel), base + STI_ENA_CLR_OFFSET);
|
|
spin_unlock_irqrestore(&mdev->lock, flags);
|
|
}
|
|
|
|
static void sti_mbox_clear_irq(struct mbox_chan *chan)
|
|
{
|
|
struct sti_channel *chan_info = chan->con_priv;
|
|
struct sti_mbox_device *mdev = chan_info->mdev;
|
|
unsigned int instance = chan_info->instance;
|
|
unsigned int channel = chan_info->channel;
|
|
void __iomem *base = MBOX_BASE(mdev, instance);
|
|
|
|
writel_relaxed(BIT(channel), base + STI_IRQ_CLR_OFFSET);
|
|
}
|
|
|
|
static struct mbox_chan *sti_mbox_irq_to_channel(struct sti_mbox_device *mdev,
|
|
unsigned int instance)
|
|
{
|
|
struct mbox_controller *mbox = mdev->mbox;
|
|
struct mbox_chan *chan = NULL;
|
|
unsigned int channel;
|
|
unsigned long bits;
|
|
void __iomem *base = MBOX_BASE(mdev, instance);
|
|
|
|
bits = readl_relaxed(base + STI_IRQ_VAL_OFFSET);
|
|
if (!bits)
|
|
/* No IRQs fired in specified instance */
|
|
return NULL;
|
|
|
|
/* An IRQ has fired, find the associated channel */
|
|
for (channel = 0; bits; channel++) {
|
|
if (!test_and_clear_bit(channel, &bits))
|
|
continue;
|
|
|
|
chan = sti_mbox_to_channel(mbox, instance, channel);
|
|
if (chan) {
|
|
dev_dbg(mbox->dev,
|
|
"IRQ fired on instance: %d channel: %d\n",
|
|
instance, channel);
|
|
break;
|
|
}
|
|
}
|
|
|
|
return chan;
|
|
}
|
|
|
|
static irqreturn_t sti_mbox_thread_handler(int irq, void *data)
|
|
{
|
|
struct sti_mbox_device *mdev = data;
|
|
struct sti_mbox_pdata *pdata = dev_get_platdata(mdev->dev);
|
|
struct mbox_chan *chan;
|
|
unsigned int instance;
|
|
|
|
for (instance = 0; instance < pdata->num_inst; instance++) {
|
|
keep_looking:
|
|
chan = sti_mbox_irq_to_channel(mdev, instance);
|
|
if (!chan)
|
|
continue;
|
|
|
|
mbox_chan_received_data(chan, NULL);
|
|
sti_mbox_clear_irq(chan);
|
|
sti_mbox_enable_channel(chan);
|
|
goto keep_looking;
|
|
}
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static irqreturn_t sti_mbox_irq_handler(int irq, void *data)
|
|
{
|
|
struct sti_mbox_device *mdev = data;
|
|
struct sti_mbox_pdata *pdata = dev_get_platdata(mdev->dev);
|
|
struct sti_channel *chan_info;
|
|
struct mbox_chan *chan;
|
|
unsigned int instance;
|
|
int ret = IRQ_NONE;
|
|
|
|
for (instance = 0; instance < pdata->num_inst; instance++) {
|
|
chan = sti_mbox_irq_to_channel(mdev, instance);
|
|
if (!chan)
|
|
continue;
|
|
chan_info = chan->con_priv;
|
|
|
|
if (!sti_mbox_channel_is_enabled(chan)) {
|
|
dev_warn(mdev->dev,
|
|
"Unexpected IRQ: %s\n"
|
|
" instance: %d: channel: %d [enabled: %x]\n",
|
|
mdev->name, chan_info->instance,
|
|
chan_info->channel, mdev->enabled[instance]);
|
|
|
|
/* Only handle IRQ if no other valid IRQs were found */
|
|
if (ret == IRQ_NONE)
|
|
ret = IRQ_HANDLED;
|
|
continue;
|
|
}
|
|
|
|
sti_mbox_disable_channel(chan);
|
|
ret = IRQ_WAKE_THREAD;
|
|
}
|
|
|
|
if (ret == IRQ_NONE)
|
|
dev_err(mdev->dev, "Spurious IRQ - was a channel requested?\n");
|
|
|
|
return ret;
|
|
}
|
|
|
|
static bool sti_mbox_tx_is_ready(struct mbox_chan *chan)
|
|
{
|
|
struct sti_channel *chan_info = chan->con_priv;
|
|
struct sti_mbox_device *mdev = chan_info->mdev;
|
|
unsigned int instance = chan_info->instance;
|
|
unsigned int channel = chan_info->channel;
|
|
void __iomem *base = MBOX_BASE(mdev, instance);
|
|
|
|
if (!(readl_relaxed(base + STI_ENA_VAL_OFFSET) & BIT(channel))) {
|
|
dev_dbg(mdev->dev, "Mbox: %s: inst: %d, chan: %d disabled\n",
|
|
mdev->name, instance, channel);
|
|
return false;
|
|
}
|
|
|
|
if (readl_relaxed(base + STI_IRQ_VAL_OFFSET) & BIT(channel)) {
|
|
dev_dbg(mdev->dev, "Mbox: %s: inst: %d, chan: %d not ready\n",
|
|
mdev->name, instance, channel);
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
static int sti_mbox_send_data(struct mbox_chan *chan, void *data)
|
|
{
|
|
struct sti_channel *chan_info = chan->con_priv;
|
|
struct sti_mbox_device *mdev = chan_info->mdev;
|
|
unsigned int instance = chan_info->instance;
|
|
unsigned int channel = chan_info->channel;
|
|
void __iomem *base = MBOX_BASE(mdev, instance);
|
|
|
|
/* Send event to co-processor */
|
|
writel_relaxed(BIT(channel), base + STI_IRQ_SET_OFFSET);
|
|
|
|
dev_dbg(mdev->dev,
|
|
"Sent via Mailbox %s: instance: %d channel: %d\n",
|
|
mdev->name, instance, channel);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int sti_mbox_startup_chan(struct mbox_chan *chan)
|
|
{
|
|
sti_mbox_clear_irq(chan);
|
|
sti_mbox_enable_channel(chan);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void sti_mbox_shutdown_chan(struct mbox_chan *chan)
|
|
{
|
|
struct sti_channel *chan_info = chan->con_priv;
|
|
struct mbox_controller *mbox = chan_info->mdev->mbox;
|
|
int i;
|
|
|
|
for (i = 0; i < mbox->num_chans; i++)
|
|
if (chan == &mbox->chans[i])
|
|
break;
|
|
|
|
if (mbox->num_chans == i) {
|
|
dev_warn(mbox->dev, "Request to free non-existent channel\n");
|
|
return;
|
|
}
|
|
|
|
/* Reset channel */
|
|
sti_mbox_disable_channel(chan);
|
|
sti_mbox_clear_irq(chan);
|
|
chan->con_priv = NULL;
|
|
}
|
|
|
|
static struct mbox_chan *sti_mbox_xlate(struct mbox_controller *mbox,
|
|
const struct of_phandle_args *spec)
|
|
{
|
|
struct sti_mbox_device *mdev = dev_get_drvdata(mbox->dev);
|
|
struct sti_mbox_pdata *pdata = dev_get_platdata(mdev->dev);
|
|
struct sti_channel *chan_info;
|
|
struct mbox_chan *chan = NULL;
|
|
unsigned int instance = spec->args[0];
|
|
unsigned int channel = spec->args[1];
|
|
int i;
|
|
|
|
/* Bounds checking */
|
|
if (instance >= pdata->num_inst || channel >= pdata->num_chan) {
|
|
dev_err(mbox->dev,
|
|
"Invalid channel requested instance: %d channel: %d\n",
|
|
instance, channel);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
for (i = 0; i < mbox->num_chans; i++) {
|
|
chan_info = mbox->chans[i].con_priv;
|
|
|
|
/* Is requested channel free? */
|
|
if (chan_info &&
|
|
mbox->dev == chan_info->mdev->dev &&
|
|
instance == chan_info->instance &&
|
|
channel == chan_info->channel) {
|
|
|
|
dev_err(mbox->dev, "Channel in use\n");
|
|
return ERR_PTR(-EBUSY);
|
|
}
|
|
|
|
/*
|
|
* Find the first free slot, then continue checking
|
|
* to see if requested channel is in use
|
|
*/
|
|
if (!chan && !chan_info)
|
|
chan = &mbox->chans[i];
|
|
}
|
|
|
|
if (!chan) {
|
|
dev_err(mbox->dev, "No free channels left\n");
|
|
return ERR_PTR(-EBUSY);
|
|
}
|
|
|
|
chan_info = devm_kzalloc(mbox->dev, sizeof(*chan_info), GFP_KERNEL);
|
|
if (!chan_info)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
chan_info->mdev = mdev;
|
|
chan_info->instance = instance;
|
|
chan_info->channel = channel;
|
|
|
|
chan->con_priv = chan_info;
|
|
|
|
dev_info(mbox->dev,
|
|
"Mbox: %s: Created channel: instance: %d channel: %d\n",
|
|
mdev->name, instance, channel);
|
|
|
|
return chan;
|
|
}
|
|
|
|
static const struct mbox_chan_ops sti_mbox_ops = {
|
|
.startup = sti_mbox_startup_chan,
|
|
.shutdown = sti_mbox_shutdown_chan,
|
|
.send_data = sti_mbox_send_data,
|
|
.last_tx_done = sti_mbox_tx_is_ready,
|
|
};
|
|
|
|
static const struct sti_mbox_pdata mbox_stih407_pdata = {
|
|
.num_inst = 4,
|
|
.num_chan = 32,
|
|
};
|
|
|
|
static const struct of_device_id sti_mailbox_match[] = {
|
|
{
|
|
.compatible = "st,stih407-mailbox",
|
|
.data = (void *)&mbox_stih407_pdata
|
|
},
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, sti_mailbox_match);
|
|
|
|
static int sti_mbox_probe(struct platform_device *pdev)
|
|
{
|
|
const struct of_device_id *match;
|
|
struct mbox_controller *mbox;
|
|
struct sti_mbox_device *mdev;
|
|
struct device_node *np = pdev->dev.of_node;
|
|
struct mbox_chan *chans;
|
|
struct resource *res;
|
|
int irq;
|
|
int ret;
|
|
|
|
match = of_match_device(sti_mailbox_match, &pdev->dev);
|
|
if (!match) {
|
|
dev_err(&pdev->dev, "No configuration found\n");
|
|
return -ENODEV;
|
|
}
|
|
pdev->dev.platform_data = (struct sti_mbox_pdata *) match->data;
|
|
|
|
mdev = devm_kzalloc(&pdev->dev, sizeof(*mdev), GFP_KERNEL);
|
|
if (!mdev)
|
|
return -ENOMEM;
|
|
|
|
platform_set_drvdata(pdev, mdev);
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
mdev->base = devm_ioremap_resource(&pdev->dev, res);
|
|
if (IS_ERR(mdev->base))
|
|
return PTR_ERR(mdev->base);
|
|
|
|
ret = of_property_read_string(np, "mbox-name", &mdev->name);
|
|
if (ret)
|
|
mdev->name = np->full_name;
|
|
|
|
mbox = devm_kzalloc(&pdev->dev, sizeof(*mbox), GFP_KERNEL);
|
|
if (!mbox)
|
|
return -ENOMEM;
|
|
|
|
chans = devm_kzalloc(&pdev->dev,
|
|
sizeof(*chans) * STI_MBOX_CHAN_MAX, GFP_KERNEL);
|
|
if (!chans)
|
|
return -ENOMEM;
|
|
|
|
mdev->dev = &pdev->dev;
|
|
mdev->mbox = mbox;
|
|
|
|
spin_lock_init(&mdev->lock);
|
|
|
|
/* STi Mailbox does not have a Tx-Done or Tx-Ready IRQ */
|
|
mbox->txdone_irq = false;
|
|
mbox->txdone_poll = true;
|
|
mbox->txpoll_period = 100;
|
|
mbox->ops = &sti_mbox_ops;
|
|
mbox->dev = mdev->dev;
|
|
mbox->of_xlate = sti_mbox_xlate;
|
|
mbox->chans = chans;
|
|
mbox->num_chans = STI_MBOX_CHAN_MAX;
|
|
|
|
ret = mbox_controller_register(mbox);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* It's okay for Tx Mailboxes to not supply IRQs */
|
|
irq = platform_get_irq(pdev, 0);
|
|
if (irq < 0) {
|
|
dev_info(&pdev->dev,
|
|
"%s: Registered Tx only Mailbox\n", mdev->name);
|
|
return 0;
|
|
}
|
|
|
|
ret = devm_request_threaded_irq(&pdev->dev, irq,
|
|
sti_mbox_irq_handler,
|
|
sti_mbox_thread_handler,
|
|
IRQF_ONESHOT, mdev->name, mdev);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "Can't claim IRQ %d\n", irq);
|
|
mbox_controller_unregister(mbox);
|
|
return -EINVAL;
|
|
}
|
|
|
|
dev_info(&pdev->dev, "%s: Registered Tx/Rx Mailbox\n", mdev->name);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int sti_mbox_remove(struct platform_device *pdev)
|
|
{
|
|
struct sti_mbox_device *mdev = platform_get_drvdata(pdev);
|
|
|
|
mbox_controller_unregister(mdev->mbox);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver sti_mbox_driver = {
|
|
.probe = sti_mbox_probe,
|
|
.remove = sti_mbox_remove,
|
|
.driver = {
|
|
.name = "sti-mailbox",
|
|
.of_match_table = sti_mailbox_match,
|
|
},
|
|
};
|
|
module_platform_driver(sti_mbox_driver);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_DESCRIPTION("STMicroelectronics Mailbox Controller");
|
|
MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org");
|
|
MODULE_ALIAS("platform:mailbox-sti");
|