[mirror_ubuntu-bionic-kernel.git] / drivers / mailbox / mailbox-test.c

/*
 * Copyright (C) 2015 ST Microelectronics
 *
 * Author: Lee Jones <lee.jones@linaro.org>
 *
 * 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 bool mbox_data_ready;
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)
{
	bool data_ready;
	unsigned long flags;

	spin_lock_irqsave(&tdev->lock, flags);
	data_ready = mbox_data_ready;
	spin_unlock_irqrestore(&tdev->lock, flags);

	return data_ready;
}

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);
	mbox_data_ready = false;

	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);
	}
	mbox_data_ready = true;
	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 <lee.jones@linaro.org");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
8ea4484d LJ	1	/*
	2	* Copyright (C) 2015 ST Microelectronics
	3	*
	4	* Author: Lee Jones <lee.jones@linaro.org>
	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
e339c80a	33	static bool mbox_data_ready;
8ea4484d LJ	34	static struct dentry *root_debugfs_dir;
	35
	36	struct mbox_test_device {
	37	struct device *dev;
2d74ffdc SH	38	void __iomem *tx_mmio;
2d74ffdc SH	39	void __iomem *rx_mmio;
8ea4484d LJ	40	struct mbox_chan *tx_channel;
	41	struct mbox_chan *rx_channel;
	42	char *rx_buffer;
	43	char *signal;
	44	char *message;
	45	spinlock_t lock;
baef9a35 SH	46	wait_queue_head_t waitq;
baef9a35 SH	47	struct fasync_struct *async_queue;
8ea4484d LJ	48	};
	49
	50	static ssize_t mbox_test_signal_write(struct file *filp,
	51	const char __user *userbuf,
	52	size_t count, loff_t *ppos)
	53	{
	54	struct mbox_test_device *tdev = filp->private_data;
8ea4484d LJ	55
	56	if (!tdev->tx_channel) {
	57	dev_err(tdev->dev, "Channel cannot do Tx\n");
	58	return -EINVAL;
	59	}
	60
	61	if (count > MBOX_MAX_SIG_LEN) {
	62	dev_err(tdev->dev,
6c03663f	63	"Signal length %zd greater than max allowed %d\n",
8ea4484d LJ	64	count, MBOX_MAX_SIG_LEN);
	65	return -EINVAL;
	66	}
	67
d1c2f87c LJ	68	/* Only allocate memory if we need to */
	69	if (!tdev->signal) {
	70	tdev->signal = kzalloc(MBOX_MAX_SIG_LEN, GFP_KERNEL);
	71	if (!tdev->signal)
	72	return -ENOMEM;
	73	}
8ea4484d	74
17f5f28f	75	if (copy_from_user(tdev->signal, userbuf, count)) {
8ea4484d	76	kfree(tdev->signal);
17f5f28f	77	tdev->signal = NULL;
8ea4484d LJ	78	return -EFAULT;
	79	}
	80
17f5f28f	81	return count;
8ea4484d LJ	82	}
	83
	84	static const struct file_operations mbox_test_signal_ops = {
	85	.write = mbox_test_signal_write,
	86	.open = simple_open,
	87	.llseek = generic_file_llseek,
	88	};
	89
baef9a35 SH	90	static int mbox_test_message_fasync(int fd, struct file *filp, int on)
	91	{
	92	struct mbox_test_device *tdev = filp->private_data;
	93
	94	return fasync_helper(fd, filp, on, &tdev->async_queue);
	95	}
	96
8ea4484d LJ	97	static ssize_t mbox_test_message_write(struct file *filp,
	98	const char __user *userbuf,
	99	size_t count, loff_t *ppos)
	100	{
	101	struct mbox_test_device *tdev = filp->private_data;
	102	void *data;
	103	int ret;
	104
	105	if (!tdev->tx_channel) {
	106	dev_err(tdev->dev, "Channel cannot do Tx\n");
	107	return -EINVAL;
	108	}
	109
	110	if (count > MBOX_MAX_MSG_LEN) {
	111	dev_err(tdev->dev,
6c03663f	112	"Message length %zd greater than max allowed %d\n",
8ea4484d LJ	113	count, MBOX_MAX_MSG_LEN);
	114	return -EINVAL;
	115	}
	116
	117	tdev->message = kzalloc(MBOX_MAX_MSG_LEN, GFP_KERNEL);
	118	if (!tdev->message)
	119	return -ENOMEM;
	120
	121	ret = copy_from_user(tdev->message, userbuf, count);
	122	if (ret) {
	123	ret = -EFAULT;
	124	goto out;
	125	}
	126
	127	/*
	128	* A separate signal is only of use if there is
	129	* MMIO to subsequently pass the message through
	130	*/
2d74ffdc	131	if (tdev->tx_mmio && tdev->signal) {
27fa680f SH	132	print_hex_dump_bytes("Client: Sending: Signal: ", DUMP_PREFIX_ADDRESS,
27fa680f SH	133	tdev->signal, MBOX_MAX_SIG_LEN);
8ea4484d LJ	134
	135	data = tdev->signal;
	136	} else
	137	data = tdev->message;
	138
27fa680f SH	139	print_hex_dump_bytes("Client: Sending: Message: ", DUMP_PREFIX_ADDRESS,
27fa680f SH	140	tdev->message, MBOX_MAX_MSG_LEN);
8ea4484d LJ	141
	142	ret = mbox_send_message(tdev->tx_channel, data);
	143	if (ret < 0)
	144	dev_err(tdev->dev, "Failed to send message via mailbox\n");
	145
	146	out:
	147	kfree(tdev->signal);
	148	kfree(tdev->message);
9ef3c511	149	tdev->signal = NULL;
8ea4484d LJ	150
	151	return ret < 0 ? ret : count;
	152	}
	153
baef9a35 SH	154	static bool mbox_test_message_data_ready(struct mbox_test_device *tdev)
baef9a35 SH	155	{
e339c80a	156	bool data_ready;
baef9a35 SH	157	unsigned long flags;
	158
	159	spin_lock_irqsave(&tdev->lock, flags);
e339c80a	160	data_ready = mbox_data_ready;
baef9a35 SH	161	spin_unlock_irqrestore(&tdev->lock, flags);
baef9a35 SH	162
e339c80a	163	return data_ready;
baef9a35 SH	164	}
baef9a35 SH	165
8ea4484d LJ	166	static ssize_t mbox_test_message_read(struct file filp, char __user userbuf,
	167	size_t count, loff_t *ppos)
	168	{
	169	struct mbox_test_device *tdev = filp->private_data;
	170	unsigned long flags;
	171	char touser, ptr;
	172	int l = 0;
	173	int ret;
	174
baef9a35 SH	175	DECLARE_WAITQUEUE(wait, current);
baef9a35 SH	176
c3ac54a6	177	touser = kzalloc(MBOX_HEXDUMP_MAX_LEN + 1, GFP_KERNEL);
8ea4484d LJ	178	if (!touser)
	179	return -ENOMEM;
	180
	181	if (!tdev->rx_channel) {
	182	ret = snprintf(touser, 20, "<NO RX CAPABILITY>\n");
	183	ret = simple_read_from_buffer(userbuf, count, ppos,
	184	touser, ret);
baef9a35	185	goto kfree_err;
8ea4484d LJ	186	}
8ea4484d LJ	187
baef9a35 SH	188	add_wait_queue(&tdev->waitq, &wait);
	189
	190	do {
	191	__set_current_state(TASK_INTERRUPTIBLE);
	192
	193	if (mbox_test_message_data_ready(tdev))
	194	break;
	195
	196	if (filp->f_flags & O_NONBLOCK) {
	197	ret = -EAGAIN;
	198	goto waitq_err;
	199	}
	200
	201	if (signal_pending(current)) {
	202	ret = -ERESTARTSYS;
	203	goto waitq_err;
	204	}
	205	schedule();
	206
	207	} while (1);
8ea4484d LJ	208
	209	spin_lock_irqsave(&tdev->lock, flags);
	210
	211	ptr = tdev->rx_buffer;
	212	while (l < MBOX_HEXDUMP_MAX_LEN) {
	213	hex_dump_to_buffer(ptr,
	214	MBOX_BYTES_PER_LINE,
	215	MBOX_BYTES_PER_LINE, 1, touser + l,
	216	MBOX_HEXDUMP_LINE_LEN, true);
	217
	218	ptr += MBOX_BYTES_PER_LINE;
	219	l += MBOX_HEXDUMP_LINE_LEN;
	220	*(touser + (l - 1)) = '\n';
	221	}
	222	*(touser + l) = '\0';
	223
	224	memset(tdev->rx_buffer, 0, MBOX_MAX_MSG_LEN);
e339c80a	225	mbox_data_ready = false;
8ea4484d LJ	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);
8ea4484d LJ	294	}
e339c80a	295	mbox_data_ready = true;
8ea4484d	296	spin_unlock_irqrestore(&tdev->lock, flags);
baef9a35 SH	297
	298	wake_up_interruptible(&tdev->waitq);
	299
	300	kill_fasync(&tdev->async_queue, SIGIO, POLL_IN);
8ea4484d LJ	301	}
	302
	303	static void mbox_test_prepare_message(struct mbox_client client, void message)
	304	{
	305	struct mbox_test_device *tdev = dev_get_drvdata(client->dev);
	306
2d74ffdc	307	if (tdev->tx_mmio) {
8ea4484d	308	if (tdev->signal)
2d74ffdc	309	memcpy_toio(tdev->tx_mmio, tdev->message, MBOX_MAX_MSG_LEN);
8ea4484d	310	else
2d74ffdc	311	memcpy_toio(tdev->tx_mmio, message, MBOX_MAX_MSG_LEN);
8ea4484d LJ	312	}
	313	}
	314
	315	static void mbox_test_message_sent(struct mbox_client *client,
	316	void *message, int r)
	317	{
	318	if (r)
	319	dev_warn(client->dev,
	320	"Client: Message could not be sent: %d\n", r);
	321	else
	322	dev_info(client->dev,
	323	"Client: Message sent\n");
	324	}
	325
	326	static struct mbox_chan *
	327	mbox_test_request_channel(struct platform_device pdev, const char name)
	328	{
	329	struct mbox_client *client;
	330	struct mbox_chan *channel;
	331
	332	client = devm_kzalloc(&pdev->dev, sizeof(*client), GFP_KERNEL);
	333	if (!client)
	334	return ERR_PTR(-ENOMEM);
	335
	336	client->dev = &pdev->dev;
	337	client->rx_callback = mbox_test_receive_message;
	338	client->tx_prepare = mbox_test_prepare_message;
	339	client->tx_done = mbox_test_message_sent;
	340	client->tx_block = true;
	341	client->knows_txdone = false;
	342	client->tx_tout = 500;
	343
	344	channel = mbox_request_channel_byname(client, name);
	345	if (IS_ERR(channel)) {
	346	dev_warn(&pdev->dev, "Failed to request %s channel\n", name);
	347	return NULL;
	348	}
	349
	350	return channel;
	351	}
	352
	353	static int mbox_test_probe(struct platform_device *pdev)
	354	{
	355	struct mbox_test_device *tdev;
	356	struct resource *res;
db4d22c0	357	resource_size_t size;
8ea4484d LJ	358	int ret;
	359
	360	tdev = devm_kzalloc(&pdev->dev, sizeof(*tdev), GFP_KERNEL);
	361	if (!tdev)
	362	return -ENOMEM;
	363
	364	/* It's okay for MMIO to be NULL */
	365	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
db4d22c0	366	size = resource_size(res);
2d74ffdc	367	tdev->tx_mmio = devm_ioremap_resource(&pdev->dev, res);
db4d22c0 SH	368	if (PTR_ERR(tdev->tx_mmio) == -EBUSY)
	369	/* if reserved area in SRAM, try just ioremap */
	370	tdev->tx_mmio = devm_ioremap(&pdev->dev, res->start, size);
	371	else if (IS_ERR(tdev->tx_mmio))
2d74ffdc SH	372	tdev->tx_mmio = NULL;
	373
	374	/* If specified, second reg entry is Rx MMIO */
	375	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
db4d22c0	376	size = resource_size(res);
2d74ffdc	377	tdev->rx_mmio = devm_ioremap_resource(&pdev->dev, res);
db4d22c0 SH	378	if (PTR_ERR(tdev->rx_mmio) == -EBUSY)
	379	tdev->rx_mmio = devm_ioremap(&pdev->dev, res->start, size);
	380	else if (IS_ERR(tdev->rx_mmio))
2d74ffdc	381	tdev->rx_mmio = tdev->tx_mmio;
8ea4484d LJ	382
	383	tdev->tx_channel = mbox_test_request_channel(pdev, "tx");
	384	tdev->rx_channel = mbox_test_request_channel(pdev, "rx");
	385
6c03663f	386	if (!tdev->tx_channel && !tdev->rx_channel)
8ea4484d LJ	387	return -EPROBE_DEFER;
8ea4484d LJ	388
2d74ffdc SH	389	/* If Rx is not specified but has Rx MMIO, then Rx = Tx */
	390	if (!tdev->rx_channel && (tdev->rx_mmio != tdev->tx_mmio))
	391	tdev->rx_channel = tdev->tx_channel;
	392
8ea4484d LJ	393	tdev->dev = &pdev->dev;
	394	platform_set_drvdata(pdev, tdev);
	395
	396	spin_lock_init(&tdev->lock);
	397
	398	if (tdev->rx_channel) {
	399	tdev->rx_buffer = devm_kzalloc(&pdev->dev,
	400	MBOX_MAX_MSG_LEN, GFP_KERNEL);
	401	if (!tdev->rx_buffer)
	402	return -ENOMEM;
	403	}
	404
	405	ret = mbox_test_add_debugfs(pdev, tdev);
	406	if (ret)
	407	return ret;
	408
baef9a35	409	init_waitqueue_head(&tdev->waitq);
8ea4484d LJ	410	dev_info(&pdev->dev, "Successfully registered\n");
	411
	412	return 0;
	413	}
	414
	415	static int mbox_test_remove(struct platform_device *pdev)
	416	{
	417	struct mbox_test_device *tdev = platform_get_drvdata(pdev);
	418
	419	debugfs_remove_recursive(root_debugfs_dir);
	420
	421	if (tdev->tx_channel)
	422	mbox_free_channel(tdev->tx_channel);
	423	if (tdev->rx_channel)
	424	mbox_free_channel(tdev->rx_channel);
	425
	426	return 0;
	427	}
	428
	429	static const struct of_device_id mbox_test_match[] = {
c4280137	430	{ .compatible = "mailbox-test" },
8ea4484d LJ	431	{},
8ea4484d LJ	432	};
f42cce3c	433	MODULE_DEVICE_TABLE(of, mbox_test_match);
8ea4484d LJ	434
	435	static struct platform_driver mbox_test_driver = {
	436	.driver = {
adf06ba9	437	.name = "mailbox_test",
8ea4484d LJ	438	.of_match_table = mbox_test_match,
	439	},
	440	.probe = mbox_test_probe,
	441	.remove = mbox_test_remove,
	442	};
	443	module_platform_driver(mbox_test_driver);
	444
	445	MODULE_DESCRIPTION("Generic Mailbox Testing Facility");
	446	MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org");
	447	MODULE_LICENSE("GPL v2");