[linux.git] / drivers / mailbox / mailbox-test.c

/*
 * Copyright (C) 2015 ST Microelectronics
 *
 * Author: Lee Jones <[email protected]>
 *
 * 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/debugfs.h>
#include <linux/err.h>
#include <linux/fs.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/mailbox_client.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/sched/signal.h>

#define MBOX_MAX_SIG_LEN	8
#define MBOX_MAX_MSG_LEN	128
#define MBOX_BYTES_PER_LINE	16
#define MBOX_HEXDUMP_LINE_LEN	((MBOX_BYTES_PER_LINE * 4) + 2)
#define MBOX_HEXDUMP_MAX_LEN	(MBOX_HEXDUMP_LINE_LEN *		\
				 (MBOX_MAX_MSG_LEN / MBOX_BYTES_PER_LINE))

static struct dentry *root_debugfs_dir;

struct mbox_test_device {
	struct device		*dev;
	void __iomem		*tx_mmio;
	void __iomem		*rx_mmio;
	struct mbox_chan	*tx_channel;
	struct mbox_chan	*rx_channel;
	char			*rx_buffer;
	char			*signal;
	char			*message;
	spinlock_t		lock;
	wait_queue_head_t	waitq;
	struct fasync_struct	*async_queue;
};

static ssize_t mbox_test_signal_write(struct file *filp,
				       const char __user *userbuf,
				       size_t count, loff_t *ppos)
{
	struct mbox_test_device *tdev = filp->private_data;

	if (!tdev->tx_channel) {
		dev_err(tdev->dev, "Channel cannot do Tx\n");
		return -EINVAL;
	}

	if (count > MBOX_MAX_SIG_LEN) {
		dev_err(tdev->dev,
			"Signal length %zd greater than max allowed %d\n",
			count, MBOX_MAX_SIG_LEN);
		return -EINVAL;
	}

	/* Only allocate memory if we need to */
	if (!tdev->signal) {
		tdev->signal = kzalloc(MBOX_MAX_SIG_LEN, GFP_KERNEL);
		if (!tdev->signal)
			return -ENOMEM;
	}

	if (copy_from_user(tdev->signal, userbuf, count)) {
		kfree(tdev->signal);
		tdev->signal = NULL;
		return -EFAULT;
	}

	return count;
}

static const struct file_operations mbox_test_signal_ops = {
	.write	= mbox_test_signal_write,
	.open	= simple_open,
	.llseek	= generic_file_llseek,
};

static int mbox_test_message_fasync(int fd, struct file *filp, int on)
{
	struct mbox_test_device *tdev = filp->private_data;

	return fasync_helper(fd, filp, on, &tdev->async_queue);
}

static ssize_t mbox_test_message_write(struct file *filp,
				       const char __user *userbuf,
				       size_t count, loff_t *ppos)
{
	struct mbox_test_device *tdev = filp->private_data;
	void *data;
	int ret;

	if (!tdev->tx_channel) {
		dev_err(tdev->dev, "Channel cannot do Tx\n");
		return -EINVAL;
	}

	if (count > MBOX_MAX_MSG_LEN) {
		dev_err(tdev->dev,
			"Message length %zd greater than max allowed %d\n",
			count, MBOX_MAX_MSG_LEN);
		return -EINVAL;
	}

	tdev->message = kzalloc(MBOX_MAX_MSG_LEN, GFP_KERNEL);
	if (!tdev->message)
		return -ENOMEM;

	ret = copy_from_user(tdev->message, userbuf, count);
	if (ret) {
		ret = -EFAULT;
		goto out;
	}

	/*
	 * A separate signal is only of use if there is
	 * MMIO to subsequently pass the message through
	 */
	if (tdev->tx_mmio && tdev->signal) {
		print_hex_dump_bytes("Client: Sending: Signal: ", DUMP_PREFIX_ADDRESS,
				     tdev->signal, MBOX_MAX_SIG_LEN);

		data = tdev->signal;
	} else
		data = tdev->message;

	print_hex_dump_bytes("Client: Sending: Message: ", DUMP_PREFIX_ADDRESS,
			     tdev->message, MBOX_MAX_MSG_LEN);

	ret = mbox_send_message(tdev->tx_channel, data);
	if (ret < 0)
		dev_err(tdev->dev, "Failed to send message via mailbox\n");

out:
	kfree(tdev->signal);
	kfree(tdev->message);
	tdev->signal = NULL;

	return ret < 0 ? ret : count;
}

static bool mbox_test_message_data_ready(struct mbox_test_device *tdev)
{
	unsigned char data;
	unsigned long flags;

	spin_lock_irqsave(&tdev->lock, flags);
	data = tdev->rx_buffer[0];
	spin_unlock_irqrestore(&tdev->lock, flags);

	if (data != '\0')
		return true;
	return false;
}

static ssize_t mbox_test_message_read(struct file *filp, char __user *userbuf,
				      size_t count, loff_t *ppos)
{
	struct mbox_test_device *tdev = filp->private_data;
	unsigned long flags;
	char *touser, *ptr;
	int l = 0;
	int ret;

	DECLARE_WAITQUEUE(wait, current);

	touser = kzalloc(MBOX_HEXDUMP_MAX_LEN + 1, GFP_KERNEL);
	if (!touser)
		return -ENOMEM;

	if (!tdev->rx_channel) {
		ret = snprintf(touser, 20, "<NO RX CAPABILITY>\n");
		ret = simple_read_from_buffer(userbuf, count, ppos,
					      touser, ret);
		goto kfree_err;
	}

	add_wait_queue(&tdev->waitq, &wait);

	do {
		__set_current_state(TASK_INTERRUPTIBLE);

		if (mbox_test_message_data_ready(tdev))
			break;

		if (filp->f_flags & O_NONBLOCK) {
			ret = -EAGAIN;
			goto waitq_err;
		}

		if (signal_pending(current)) {
			ret = -ERESTARTSYS;
			goto waitq_err;
		}
		schedule();

	} while (1);

	spin_lock_irqsave(&tdev->lock, flags);

	ptr = tdev->rx_buffer;
	while (l < MBOX_HEXDUMP_MAX_LEN) {
		hex_dump_to_buffer(ptr,
				   MBOX_BYTES_PER_LINE,
				   MBOX_BYTES_PER_LINE, 1, touser + l,
				   MBOX_HEXDUMP_LINE_LEN, true);

		ptr += MBOX_BYTES_PER_LINE;
		l += MBOX_HEXDUMP_LINE_LEN;
		*(touser + (l - 1)) = '\n';
	}
	*(touser + l) = '\0';

	memset(tdev->rx_buffer, 0, MBOX_MAX_MSG_LEN);

	spin_unlock_irqrestore(&tdev->lock, flags);

	ret = simple_read_from_buffer(userbuf, count, ppos, touser, MBOX_HEXDUMP_MAX_LEN);
waitq_err:
	__set_current_state(TASK_RUNNING);
	remove_wait_queue(&tdev->waitq, &wait);
kfree_err:
	kfree(touser);
	return ret;
}

static unsigned int
mbox_test_message_poll(struct file *filp, struct poll_table_struct *wait)
{
	struct mbox_test_device *tdev = filp->private_data;

	poll_wait(filp, &tdev->waitq, wait);

	if (mbox_test_message_data_ready(tdev))
		return POLLIN | POLLRDNORM;
	return 0;
}

static const struct file_operations mbox_test_message_ops = {
	.write	= mbox_test_message_write,
	.read	= mbox_test_message_read,
	.fasync	= mbox_test_message_fasync,
	.poll	= mbox_test_message_poll,
	.open	= simple_open,
	.llseek	= generic_file_llseek,
};

static int mbox_test_add_debugfs(struct platform_device *pdev,
				 struct mbox_test_device *tdev)
{
	if (!debugfs_initialized())
		return 0;

	root_debugfs_dir = debugfs_create_dir("mailbox", NULL);
	if (!root_debugfs_dir) {
		dev_err(&pdev->dev, "Failed to create Mailbox debugfs\n");
		return -EINVAL;
	}

	debugfs_create_file("message", 0600, root_debugfs_dir,
			    tdev, &mbox_test_message_ops);

	debugfs_create_file("signal", 0200, root_debugfs_dir,
			    tdev, &mbox_test_signal_ops);

	return 0;
}

static void mbox_test_receive_message(struct mbox_client *client, void *message)
{
	struct mbox_test_device *tdev = dev_get_drvdata(client->dev);
	unsigned long flags;

	spin_lock_irqsave(&tdev->lock, flags);
	if (tdev->rx_mmio) {
		memcpy_fromio(tdev->rx_buffer, tdev->rx_mmio, MBOX_MAX_MSG_LEN);
		print_hex_dump_bytes("Client: Received [MMIO]: ", DUMP_PREFIX_ADDRESS,
				     tdev->rx_buffer, MBOX_MAX_MSG_LEN);
	} else if (message) {
		print_hex_dump_bytes("Client: Received [API]: ", DUMP_PREFIX_ADDRESS,
				     message, MBOX_MAX_MSG_LEN);
		memcpy(tdev->rx_buffer, message, MBOX_MAX_MSG_LEN);
	}
	spin_unlock_irqrestore(&tdev->lock, flags);

	wake_up_interruptible(&tdev->waitq);

	kill_fasync(&tdev->async_queue, SIGIO, POLL_IN);
}

static void mbox_test_prepare_message(struct mbox_client *client, void *message)
{
	struct mbox_test_device *tdev = dev_get_drvdata(client->dev);

	if (tdev->tx_mmio) {
		if (tdev->signal)
			memcpy_toio(tdev->tx_mmio, tdev->message, MBOX_MAX_MSG_LEN);
		else
			memcpy_toio(tdev->tx_mmio, message, MBOX_MAX_MSG_LEN);
	}
}

static void mbox_test_message_sent(struct mbox_client *client,
				   void *message, int r)
{
	if (r)
		dev_warn(client->dev,
			 "Client: Message could not be sent: %d\n", r);
	else
		dev_info(client->dev,
			 "Client: Message sent\n");
}

static struct mbox_chan *
mbox_test_request_channel(struct platform_device *pdev, const char *name)
{
	struct mbox_client *client;
	struct mbox_chan *channel;

	client = devm_kzalloc(&pdev->dev, sizeof(*client), GFP_KERNEL);
	if (!client)
		return ERR_PTR(-ENOMEM);

	client->dev		= &pdev->dev;
	client->rx_callback	= mbox_test_receive_message;
	client->tx_prepare	= mbox_test_prepare_message;
	client->tx_done		= mbox_test_message_sent;
	client->tx_block	= true;
	client->knows_txdone	= false;
	client->tx_tout		= 500;

	channel = mbox_request_channel_byname(client, name);
	if (IS_ERR(channel)) {
		dev_warn(&pdev->dev, "Failed to request %s channel\n", name);
		return NULL;
	}

	return channel;
}

static int mbox_test_probe(struct platform_device *pdev)
{
	struct mbox_test_device *tdev;
	struct resource *res;
	resource_size_t size;
	int ret;

	tdev = devm_kzalloc(&pdev->dev, sizeof(*tdev), GFP_KERNEL);
	if (!tdev)
		return -ENOMEM;

	/* It's okay for MMIO to be NULL */
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	size = resource_size(res);
	tdev->tx_mmio = devm_ioremap_resource(&pdev->dev, res);
	if (PTR_ERR(tdev->tx_mmio) == -EBUSY)
		/* if reserved area in SRAM, try just ioremap */
		tdev->tx_mmio = devm_ioremap(&pdev->dev, res->start, size);
	else if (IS_ERR(tdev->tx_mmio))
		tdev->tx_mmio = NULL;

	/* If specified, second reg entry is Rx MMIO */
	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
	size = resource_size(res);
	tdev->rx_mmio = devm_ioremap_resource(&pdev->dev, res);
	if (PTR_ERR(tdev->rx_mmio) == -EBUSY)
		tdev->rx_mmio = devm_ioremap(&pdev->dev, res->start, size);
	else if (IS_ERR(tdev->rx_mmio))
		tdev->rx_mmio = tdev->tx_mmio;

	tdev->tx_channel = mbox_test_request_channel(pdev, "tx");
	tdev->rx_channel = mbox_test_request_channel(pdev, "rx");

	if (!tdev->tx_channel && !tdev->rx_channel)
		return -EPROBE_DEFER;

	/* If Rx is not specified but has Rx MMIO, then Rx = Tx */
	if (!tdev->rx_channel && (tdev->rx_mmio != tdev->tx_mmio))
		tdev->rx_channel = tdev->tx_channel;

	tdev->dev = &pdev->dev;
	platform_set_drvdata(pdev, tdev);

	spin_lock_init(&tdev->lock);

	if (tdev->rx_channel) {
		tdev->rx_buffer = devm_kzalloc(&pdev->dev,
					       MBOX_MAX_MSG_LEN, GFP_KERNEL);
		if (!tdev->rx_buffer)
			return -ENOMEM;
	}

	ret = mbox_test_add_debugfs(pdev, tdev);
	if (ret)
		return ret;

	init_waitqueue_head(&tdev->waitq);
	dev_info(&pdev->dev, "Successfully registered\n");

	return 0;
}

static int mbox_test_remove(struct platform_device *pdev)
{
	struct mbox_test_device *tdev = platform_get_drvdata(pdev);

	debugfs_remove_recursive(root_debugfs_dir);

	if (tdev->tx_channel)
		mbox_free_channel(tdev->tx_channel);
	if (tdev->rx_channel)
		mbox_free_channel(tdev->rx_channel);

	return 0;
}

static const struct of_device_id mbox_test_match[] = {
	{ .compatible = "mailbox-test" },
	{},
};
MODULE_DEVICE_TABLE(of, mbox_test_match);

static struct platform_driver mbox_test_driver = {
	.driver = {
		.name = "mailbox_test",
		.of_match_table = mbox_test_match,
	},
	.probe  = mbox_test_probe,
	.remove = mbox_test_remove,
};
module_platform_driver(mbox_test_driver);

MODULE_DESCRIPTION("Generic Mailbox Testing Facility");
MODULE_AUTHOR("Lee Jones <[email protected]");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
8ea4484d LJ	1	/*
	2	* Copyright (C) 2015 ST Microelectronics
	3	*
	4	* Author: Lee Jones <[email protected]>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*/
	11
	12	#include <linux/debugfs.h>
	13	#include <linux/err.h>
baef9a35	14	#include <linux/fs.h>
a133f8b6	15	#include <linux/io.h>
8ea4484d LJ	16	#include <linux/kernel.h>
	17	#include <linux/mailbox_client.h>
	18	#include <linux/module.h>
	19	#include <linux/of.h>
	20	#include <linux/platform_device.h>
baef9a35	21	#include <linux/poll.h>
8ea4484d LJ	22	#include <linux/slab.h>
8ea4484d LJ	23	#include <linux/uaccess.h>
174cd4b1	24	#include <linux/sched/signal.h>
8ea4484d LJ	25
	26	#define MBOX_MAX_SIG_LEN 8
	27	#define MBOX_MAX_MSG_LEN 128
	28	#define MBOX_BYTES_PER_LINE 16
6c03663f	29	#define MBOX_HEXDUMP_LINE_LEN ((MBOX_BYTES_PER_LINE * 4) + 2)
8ea4484d LJ	30	#define MBOX_HEXDUMP_MAX_LEN (MBOX_HEXDUMP_LINE_LEN * \
	31	(MBOX_MAX_MSG_LEN / MBOX_BYTES_PER_LINE))
	32
	33	static struct dentry *root_debugfs_dir;
	34
	35	struct mbox_test_device {
	36	struct device *dev;
2d74ffdc SH	37	void __iomem *tx_mmio;
2d74ffdc SH	38	void __iomem *rx_mmio;
8ea4484d LJ	39	struct mbox_chan *tx_channel;
	40	struct mbox_chan *rx_channel;
	41	char *rx_buffer;
	42	char *signal;
	43	char *message;
	44	spinlock_t lock;
baef9a35 SH	45	wait_queue_head_t waitq;
baef9a35 SH	46	struct fasync_struct *async_queue;
8ea4484d LJ	47	};
	48
	49	static ssize_t mbox_test_signal_write(struct file *filp,
	50	const char __user *userbuf,
	51	size_t count, loff_t *ppos)
	52	{
	53	struct mbox_test_device *tdev = filp->private_data;
8ea4484d LJ	54
	55	if (!tdev->tx_channel) {
	56	dev_err(tdev->dev, "Channel cannot do Tx\n");
	57	return -EINVAL;
	58	}
	59
	60	if (count > MBOX_MAX_SIG_LEN) {
	61	dev_err(tdev->dev,
6c03663f	62	"Signal length %zd greater than max allowed %d\n",
8ea4484d LJ	63	count, MBOX_MAX_SIG_LEN);
	64	return -EINVAL;
	65	}
	66
d1c2f87c LJ	67	/* Only allocate memory if we need to */
	68	if (!tdev->signal) {
	69	tdev->signal = kzalloc(MBOX_MAX_SIG_LEN, GFP_KERNEL);
	70	if (!tdev->signal)
	71	return -ENOMEM;
	72	}
8ea4484d	73
17f5f28f	74	if (copy_from_user(tdev->signal, userbuf, count)) {
8ea4484d	75	kfree(tdev->signal);
17f5f28f	76	tdev->signal = NULL;
8ea4484d LJ	77	return -EFAULT;
	78	}
	79
17f5f28f	80	return count;
8ea4484d LJ	81	}
	82
	83	static const struct file_operations mbox_test_signal_ops = {
	84	.write = mbox_test_signal_write,
	85	.open = simple_open,
	86	.llseek = generic_file_llseek,
	87	};
	88
baef9a35 SH	89	static int mbox_test_message_fasync(int fd, struct file *filp, int on)
	90	{
	91	struct mbox_test_device *tdev = filp->private_data;
	92
	93	return fasync_helper(fd, filp, on, &tdev->async_queue);
	94	}
	95
8ea4484d LJ	96	static ssize_t mbox_test_message_write(struct file *filp,
	97	const char __user *userbuf,
	98	size_t count, loff_t *ppos)
	99	{
	100	struct mbox_test_device *tdev = filp->private_data;
	101	void *data;
	102	int ret;
	103
	104	if (!tdev->tx_channel) {
	105	dev_err(tdev->dev, "Channel cannot do Tx\n");
	106	return -EINVAL;
	107	}
	108
	109	if (count > MBOX_MAX_MSG_LEN) {
	110	dev_err(tdev->dev,
6c03663f	111	"Message length %zd greater than max allowed %d\n",
8ea4484d LJ	112	count, MBOX_MAX_MSG_LEN);
	113	return -EINVAL;
	114	}
	115
	116	tdev->message = kzalloc(MBOX_MAX_MSG_LEN, GFP_KERNEL);
	117	if (!tdev->message)
	118	return -ENOMEM;
	119
	120	ret = copy_from_user(tdev->message, userbuf, count);
	121	if (ret) {
	122	ret = -EFAULT;
	123	goto out;
	124	}
	125
	126	/*
	127	* A separate signal is only of use if there is
	128	* MMIO to subsequently pass the message through
	129	*/
2d74ffdc	130	if (tdev->tx_mmio && tdev->signal) {
27fa680f SH	131	print_hex_dump_bytes("Client: Sending: Signal: ", DUMP_PREFIX_ADDRESS,
27fa680f SH	132	tdev->signal, MBOX_MAX_SIG_LEN);
8ea4484d LJ	133
	134	data = tdev->signal;
	135	} else
	136	data = tdev->message;
	137
27fa680f SH	138	print_hex_dump_bytes("Client: Sending: Message: ", DUMP_PREFIX_ADDRESS,
27fa680f SH	139	tdev->message, MBOX_MAX_MSG_LEN);
8ea4484d LJ	140
	141	ret = mbox_send_message(tdev->tx_channel, data);
	142	if (ret < 0)
	143	dev_err(tdev->dev, "Failed to send message via mailbox\n");
	144
	145	out:
	146	kfree(tdev->signal);
	147	kfree(tdev->message);
9ef3c511	148	tdev->signal = NULL;
8ea4484d LJ	149
	150	return ret < 0 ? ret : count;
	151	}
	152
baef9a35 SH	153	static bool mbox_test_message_data_ready(struct mbox_test_device *tdev)
	154	{
	155	unsigned char data;
	156	unsigned long flags;
	157
	158	spin_lock_irqsave(&tdev->lock, flags);
	159	data = tdev->rx_buffer[0];
	160	spin_unlock_irqrestore(&tdev->lock, flags);
	161
	162	if (data != '\0')
	163	return true;
	164	return false;
	165	}
	166
8ea4484d LJ	167	static ssize_t mbox_test_message_read(struct file filp, char __user userbuf,
	168	size_t count, loff_t *ppos)
	169	{
	170	struct mbox_test_device *tdev = filp->private_data;
	171	unsigned long flags;
	172	char touser, ptr;
	173	int l = 0;
	174	int ret;
	175
baef9a35 SH	176	DECLARE_WAITQUEUE(wait, current);
baef9a35 SH	177
c3ac54a6	178	touser = kzalloc(MBOX_HEXDUMP_MAX_LEN + 1, GFP_KERNEL);
8ea4484d LJ	179	if (!touser)
	180	return -ENOMEM;
	181
	182	if (!tdev->rx_channel) {
	183	ret = snprintf(touser, 20, "<NO RX CAPABILITY>\n");
	184	ret = simple_read_from_buffer(userbuf, count, ppos,
	185	touser, ret);
baef9a35	186	goto kfree_err;
8ea4484d LJ	187	}
8ea4484d LJ	188
baef9a35 SH	189	add_wait_queue(&tdev->waitq, &wait);
	190
	191	do {
	192	__set_current_state(TASK_INTERRUPTIBLE);
	193
	194	if (mbox_test_message_data_ready(tdev))
	195	break;
	196
	197	if (filp->f_flags & O_NONBLOCK) {
	198	ret = -EAGAIN;
	199	goto waitq_err;
	200	}
	201
	202	if (signal_pending(current)) {
	203	ret = -ERESTARTSYS;
	204	goto waitq_err;
	205	}
	206	schedule();
	207
	208	} while (1);
8ea4484d LJ	209
	210	spin_lock_irqsave(&tdev->lock, flags);
	211
	212	ptr = tdev->rx_buffer;
	213	while (l < MBOX_HEXDUMP_MAX_LEN) {
	214	hex_dump_to_buffer(ptr,
	215	MBOX_BYTES_PER_LINE,
	216	MBOX_BYTES_PER_LINE, 1, touser + l,
	217	MBOX_HEXDUMP_LINE_LEN, true);
	218
	219	ptr += MBOX_BYTES_PER_LINE;
	220	l += MBOX_HEXDUMP_LINE_LEN;
	221	*(touser + (l - 1)) = '\n';
	222	}
	223	*(touser + l) = '\0';
	224
	225	memset(tdev->rx_buffer, 0, MBOX_MAX_MSG_LEN);
	226
	227	spin_unlock_irqrestore(&tdev->lock, flags);
	228
	229	ret = simple_read_from_buffer(userbuf, count, ppos, touser, MBOX_HEXDUMP_MAX_LEN);
baef9a35 SH	230	waitq_err:
	231	__set_current_state(TASK_RUNNING);
	232	remove_wait_queue(&tdev->waitq, &wait);
	233	kfree_err:
8ea4484d LJ	234	kfree(touser);
	235	return ret;
	236	}
	237
baef9a35 SH	238	static unsigned int
	239	mbox_test_message_poll(struct file filp, struct poll_table_struct wait)
	240	{
	241	struct mbox_test_device *tdev = filp->private_data;
	242
	243	poll_wait(filp, &tdev->waitq, wait);
	244
	245	if (mbox_test_message_data_ready(tdev))
	246	return POLLIN \| POLLRDNORM;
	247	return 0;
	248	}
	249
8ea4484d LJ	250	static const struct file_operations mbox_test_message_ops = {
	251	.write = mbox_test_message_write,
	252	.read = mbox_test_message_read,
baef9a35 SH	253	.fasync = mbox_test_message_fasync,
baef9a35 SH	254	.poll = mbox_test_message_poll,
8ea4484d LJ	255	.open = simple_open,
	256	.llseek = generic_file_llseek,
	257	};
	258
	259	static int mbox_test_add_debugfs(struct platform_device *pdev,
	260	struct mbox_test_device *tdev)
	261	{
	262	if (!debugfs_initialized())
	263	return 0;
	264
	265	root_debugfs_dir = debugfs_create_dir("mailbox", NULL);
	266	if (!root_debugfs_dir) {
	267	dev_err(&pdev->dev, "Failed to create Mailbox debugfs\n");
	268	return -EINVAL;
	269	}
	270
	271	debugfs_create_file("message", 0600, root_debugfs_dir,
	272	tdev, &mbox_test_message_ops);
	273
	274	debugfs_create_file("signal", 0200, root_debugfs_dir,
	275	tdev, &mbox_test_signal_ops);
	276
	277	return 0;
	278	}
	279
	280	static void mbox_test_receive_message(struct mbox_client client, void message)
	281	{
	282	struct mbox_test_device *tdev = dev_get_drvdata(client->dev);
	283	unsigned long flags;
	284
	285	spin_lock_irqsave(&tdev->lock, flags);
2d74ffdc SH	286	if (tdev->rx_mmio) {
2d74ffdc SH	287	memcpy_fromio(tdev->rx_buffer, tdev->rx_mmio, MBOX_MAX_MSG_LEN);
27fa680f SH	288	print_hex_dump_bytes("Client: Received [MMIO]: ", DUMP_PREFIX_ADDRESS,
27fa680f SH	289	tdev->rx_buffer, MBOX_MAX_MSG_LEN);
8ea4484d	290	} else if (message) {
27fa680f SH	291	print_hex_dump_bytes("Client: Received [API]: ", DUMP_PREFIX_ADDRESS,
27fa680f SH	292	message, MBOX_MAX_MSG_LEN);
8ea4484d LJ	293	memcpy(tdev->rx_buffer, message, MBOX_MAX_MSG_LEN);
	294	}
	295	spin_unlock_irqrestore(&tdev->lock, flags);
baef9a35 SH	296
	297	wake_up_interruptible(&tdev->waitq);
	298
	299	kill_fasync(&tdev->async_queue, SIGIO, POLL_IN);
8ea4484d LJ	300	}
	301
	302	static void mbox_test_prepare_message(struct mbox_client client, void message)
	303	{
	304	struct mbox_test_device *tdev = dev_get_drvdata(client->dev);
	305
2d74ffdc	306	if (tdev->tx_mmio) {
8ea4484d	307	if (tdev->signal)
2d74ffdc	308	memcpy_toio(tdev->tx_mmio, tdev->message, MBOX_MAX_MSG_LEN);
8ea4484d	309	else
2d74ffdc	310	memcpy_toio(tdev->tx_mmio, message, MBOX_MAX_MSG_LEN);
8ea4484d LJ	311	}
	312	}
	313
	314	static void mbox_test_message_sent(struct mbox_client *client,
	315	void *message, int r)
	316	{
	317	if (r)
	318	dev_warn(client->dev,
	319	"Client: Message could not be sent: %d\n", r);
	320	else
	321	dev_info(client->dev,
	322	"Client: Message sent\n");
	323	}
	324
	325	static struct mbox_chan *
	326	mbox_test_request_channel(struct platform_device pdev, const char name)
	327	{
	328	struct mbox_client *client;
	329	struct mbox_chan *channel;
	330
	331	client = devm_kzalloc(&pdev->dev, sizeof(*client), GFP_KERNEL);
	332	if (!client)
	333	return ERR_PTR(-ENOMEM);
	334
	335	client->dev = &pdev->dev;
	336	client->rx_callback = mbox_test_receive_message;
	337	client->tx_prepare = mbox_test_prepare_message;
	338	client->tx_done = mbox_test_message_sent;
	339	client->tx_block = true;
	340	client->knows_txdone = false;
	341	client->tx_tout = 500;
	342
	343	channel = mbox_request_channel_byname(client, name);
	344	if (IS_ERR(channel)) {
	345	dev_warn(&pdev->dev, "Failed to request %s channel\n", name);
	346	return NULL;
	347	}
	348
	349	return channel;
	350	}
	351
	352	static int mbox_test_probe(struct platform_device *pdev)
	353	{
	354	struct mbox_test_device *tdev;
	355	struct resource *res;
db4d22c0	356	resource_size_t size;
8ea4484d LJ	357	int ret;
	358
	359	tdev = devm_kzalloc(&pdev->dev, sizeof(*tdev), GFP_KERNEL);
	360	if (!tdev)
	361	return -ENOMEM;
	362
	363	/* It's okay for MMIO to be NULL */
	364	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
db4d22c0	365	size = resource_size(res);
2d74ffdc	366	tdev->tx_mmio = devm_ioremap_resource(&pdev->dev, res);
db4d22c0 SH	367	if (PTR_ERR(tdev->tx_mmio) == -EBUSY)
	368	/* if reserved area in SRAM, try just ioremap */
	369	tdev->tx_mmio = devm_ioremap(&pdev->dev, res->start, size);
	370	else if (IS_ERR(tdev->tx_mmio))
2d74ffdc SH	371	tdev->tx_mmio = NULL;
	372
	373	/* If specified, second reg entry is Rx MMIO */
	374	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
db4d22c0	375	size = resource_size(res);
2d74ffdc	376	tdev->rx_mmio = devm_ioremap_resource(&pdev->dev, res);
db4d22c0 SH	377	if (PTR_ERR(tdev->rx_mmio) == -EBUSY)
	378	tdev->rx_mmio = devm_ioremap(&pdev->dev, res->start, size);
	379	else if (IS_ERR(tdev->rx_mmio))
2d74ffdc	380	tdev->rx_mmio = tdev->tx_mmio;
8ea4484d LJ	381
	382	tdev->tx_channel = mbox_test_request_channel(pdev, "tx");
	383	tdev->rx_channel = mbox_test_request_channel(pdev, "rx");
	384
6c03663f	385	if (!tdev->tx_channel && !tdev->rx_channel)
8ea4484d LJ	386	return -EPROBE_DEFER;
8ea4484d LJ	387
2d74ffdc SH	388	/* If Rx is not specified but has Rx MMIO, then Rx = Tx */
	389	if (!tdev->rx_channel && (tdev->rx_mmio != tdev->tx_mmio))
	390	tdev->rx_channel = tdev->tx_channel;
	391
8ea4484d LJ	392	tdev->dev = &pdev->dev;
	393	platform_set_drvdata(pdev, tdev);
	394
	395	spin_lock_init(&tdev->lock);
	396
	397	if (tdev->rx_channel) {
	398	tdev->rx_buffer = devm_kzalloc(&pdev->dev,
	399	MBOX_MAX_MSG_LEN, GFP_KERNEL);
	400	if (!tdev->rx_buffer)
	401	return -ENOMEM;
	402	}
	403
	404	ret = mbox_test_add_debugfs(pdev, tdev);
	405	if (ret)
	406	return ret;
	407
baef9a35	408	init_waitqueue_head(&tdev->waitq);
8ea4484d LJ	409	dev_info(&pdev->dev, "Successfully registered\n");
	410
	411	return 0;
	412	}
	413
	414	static int mbox_test_remove(struct platform_device *pdev)
	415	{
	416	struct mbox_test_device *tdev = platform_get_drvdata(pdev);
	417
	418	debugfs_remove_recursive(root_debugfs_dir);
	419
	420	if (tdev->tx_channel)
	421	mbox_free_channel(tdev->tx_channel);
	422	if (tdev->rx_channel)
	423	mbox_free_channel(tdev->rx_channel);
	424
	425	return 0;
	426	}
	427
	428	static const struct of_device_id mbox_test_match[] = {
c4280137	429	{ .compatible = "mailbox-test" },
8ea4484d LJ	430	{},
8ea4484d LJ	431	};
f42cce3c	432	MODULE_DEVICE_TABLE(of, mbox_test_match);
8ea4484d LJ	433
	434	static struct platform_driver mbox_test_driver = {
	435	.driver = {
adf06ba9	436	.name = "mailbox_test",
8ea4484d LJ	437	.of_match_table = mbox_test_match,
	438	},
	439	.probe = mbox_test_probe,
	440	.remove = mbox_test_remove,
	441	};
	442	module_platform_driver(mbox_test_driver);
	443
	444	MODULE_DESCRIPTION("Generic Mailbox Testing Facility");
	445	MODULE_AUTHOR("Lee Jones <[email protected]");
	446	MODULE_LICENSE("GPL v2");