2 * Copyright (C) 2015 ST Microelectronics
4 * Author: Lee Jones <lee.jones@linaro.org>
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.
12 #include <linux/debugfs.h>
13 #include <linux/err.h>
14 #include <linux/kernel.h>
15 #include <linux/mailbox_client.h>
16 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/slab.h>
20 #include <linux/uaccess.h>
22 #define MBOX_MAX_SIG_LEN 8
23 #define MBOX_MAX_MSG_LEN 128
24 #define MBOX_BYTES_PER_LINE 16
25 #define MBOX_HEXDUMP_LINE_LEN ((MBOX_BYTES_PER_LINE * 4) + 2)
26 #define MBOX_HEXDUMP_MAX_LEN (MBOX_HEXDUMP_LINE_LEN * \
27 (MBOX_MAX_MSG_LEN / MBOX_BYTES_PER_LINE))
29 static struct dentry *root_debugfs_dir;
31 struct mbox_test_device {
34 struct mbox_chan *tx_channel;
35 struct mbox_chan *rx_channel;
42 static ssize_t mbox_test_signal_write(struct file *filp,
43 const char __user *userbuf,
44 size_t count, loff_t *ppos)
46 struct mbox_test_device *tdev = filp->private_data;
49 if (!tdev->tx_channel) {
50 dev_err(tdev->dev, "Channel cannot do Tx\n");
54 if (count > MBOX_MAX_SIG_LEN) {
56 "Signal length %d greater than max allowed %d\n",
57 count, MBOX_MAX_SIG_LEN);
61 tdev->signal = kzalloc(MBOX_MAX_SIG_LEN, GFP_KERNEL);
65 ret = copy_from_user(tdev->signal, userbuf, count);
71 return ret < 0 ? ret : count;
74 static const struct file_operations mbox_test_signal_ops = {
75 .write = mbox_test_signal_write,
77 .llseek = generic_file_llseek,
80 static ssize_t mbox_test_message_write(struct file *filp,
81 const char __user *userbuf,
82 size_t count, loff_t *ppos)
84 struct mbox_test_device *tdev = filp->private_data;
88 if (!tdev->tx_channel) {
89 dev_err(tdev->dev, "Channel cannot do Tx\n");
93 if (count > MBOX_MAX_MSG_LEN) {
95 "Message length %d greater than max allowed %d\n",
96 count, MBOX_MAX_MSG_LEN);
100 tdev->message = kzalloc(MBOX_MAX_MSG_LEN, GFP_KERNEL);
104 ret = copy_from_user(tdev->message, userbuf, count);
111 * A separate signal is only of use if there is
112 * MMIO to subsequently pass the message through
114 if (tdev->mmio && tdev->signal) {
115 print_hex_dump(KERN_INFO, "Client: Sending: Signal: ", DUMP_PREFIX_ADDRESS,
116 MBOX_BYTES_PER_LINE, 1, tdev->signal, MBOX_MAX_SIG_LEN, true);
120 data = tdev->message;
122 print_hex_dump(KERN_INFO, "Client: Sending: Message: ", DUMP_PREFIX_ADDRESS,
123 MBOX_BYTES_PER_LINE, 1, tdev->message, MBOX_MAX_MSG_LEN, true);
125 ret = mbox_send_message(tdev->tx_channel, data);
127 dev_err(tdev->dev, "Failed to send message via mailbox\n");
131 kfree(tdev->message);
133 return ret < 0 ? ret : count;
136 static ssize_t mbox_test_message_read(struct file *filp, char __user *userbuf,
137 size_t count, loff_t *ppos)
139 struct mbox_test_device *tdev = filp->private_data;
145 touser = kzalloc(MBOX_HEXDUMP_MAX_LEN, GFP_KERNEL);
149 if (!tdev->rx_channel) {
150 ret = snprintf(touser, 20, "<NO RX CAPABILITY>\n");
151 ret = simple_read_from_buffer(userbuf, count, ppos,
156 if (tdev->rx_buffer[0] == '\0') {
157 ret = snprintf(touser, 9, "<EMPTY>\n");
158 ret = simple_read_from_buffer(userbuf, count, ppos,
163 spin_lock_irqsave(&tdev->lock, flags);
165 ptr = tdev->rx_buffer;
166 while (l < MBOX_HEXDUMP_MAX_LEN) {
167 hex_dump_to_buffer(ptr,
169 MBOX_BYTES_PER_LINE, 1, touser + l,
170 MBOX_HEXDUMP_LINE_LEN, true);
172 ptr += MBOX_BYTES_PER_LINE;
173 l += MBOX_HEXDUMP_LINE_LEN;
174 *(touser + (l - 1)) = '\n';
176 *(touser + l) = '\0';
178 memset(tdev->rx_buffer, 0, MBOX_MAX_MSG_LEN);
180 spin_unlock_irqrestore(&tdev->lock, flags);
182 ret = simple_read_from_buffer(userbuf, count, ppos, touser, MBOX_HEXDUMP_MAX_LEN);
188 static const struct file_operations mbox_test_message_ops = {
189 .write = mbox_test_message_write,
190 .read = mbox_test_message_read,
192 .llseek = generic_file_llseek,
195 static int mbox_test_add_debugfs(struct platform_device *pdev,
196 struct mbox_test_device *tdev)
198 if (!debugfs_initialized())
201 root_debugfs_dir = debugfs_create_dir("mailbox", NULL);
202 if (!root_debugfs_dir) {
203 dev_err(&pdev->dev, "Failed to create Mailbox debugfs\n");
207 debugfs_create_file("message", 0600, root_debugfs_dir,
208 tdev, &mbox_test_message_ops);
210 debugfs_create_file("signal", 0200, root_debugfs_dir,
211 tdev, &mbox_test_signal_ops);
216 static void mbox_test_receive_message(struct mbox_client *client, void *message)
218 struct mbox_test_device *tdev = dev_get_drvdata(client->dev);
221 spin_lock_irqsave(&tdev->lock, flags);
223 print_hex_dump(KERN_INFO, "Client: Received [MMIO]: ",
224 DUMP_PREFIX_ADDRESS, MBOX_BYTES_PER_LINE, 1,
225 tdev->mmio, MBOX_MAX_MSG_LEN, true);
226 memcpy(tdev->rx_buffer, tdev->mmio, MBOX_MAX_MSG_LEN);
228 } else if (message) {
229 print_hex_dump(KERN_INFO, "Client: Received [API]: ",
230 DUMP_PREFIX_ADDRESS, MBOX_BYTES_PER_LINE, 1,
231 message, MBOX_MAX_MSG_LEN, true);
232 memcpy(tdev->rx_buffer, message, MBOX_MAX_MSG_LEN);
234 spin_unlock_irqrestore(&tdev->lock, flags);
237 static void mbox_test_prepare_message(struct mbox_client *client, void *message)
239 struct mbox_test_device *tdev = dev_get_drvdata(client->dev);
243 memcpy(tdev->mmio, tdev->message, MBOX_MAX_MSG_LEN);
245 memcpy(tdev->mmio, message, MBOX_MAX_MSG_LEN);
249 static void mbox_test_message_sent(struct mbox_client *client,
250 void *message, int r)
253 dev_warn(client->dev,
254 "Client: Message could not be sent: %d\n", r);
256 dev_info(client->dev,
257 "Client: Message sent\n");
260 static struct mbox_chan *
261 mbox_test_request_channel(struct platform_device *pdev, const char *name)
263 struct mbox_client *client;
264 struct mbox_chan *channel;
266 client = devm_kzalloc(&pdev->dev, sizeof(*client), GFP_KERNEL);
268 return ERR_PTR(-ENOMEM);
270 client->dev = &pdev->dev;
271 client->rx_callback = mbox_test_receive_message;
272 client->tx_prepare = mbox_test_prepare_message;
273 client->tx_done = mbox_test_message_sent;
274 client->tx_block = true;
275 client->knows_txdone = false;
276 client->tx_tout = 500;
278 channel = mbox_request_channel_byname(client, name);
279 if (IS_ERR(channel)) {
280 dev_warn(&pdev->dev, "Failed to request %s channel\n", name);
287 static int mbox_test_probe(struct platform_device *pdev)
289 struct mbox_test_device *tdev;
290 struct resource *res;
293 tdev = devm_kzalloc(&pdev->dev, sizeof(*tdev), GFP_KERNEL);
297 /* It's okay for MMIO to be NULL */
298 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
299 tdev->mmio = devm_ioremap_resource(&pdev->dev, res);
300 if (IS_ERR(tdev->mmio))
303 tdev->tx_channel = mbox_test_request_channel(pdev, "tx");
304 tdev->rx_channel = mbox_test_request_channel(pdev, "rx");
306 if (!tdev->tx_channel && !tdev->tx_channel)
307 return -EPROBE_DEFER;
309 tdev->dev = &pdev->dev;
310 platform_set_drvdata(pdev, tdev);
312 spin_lock_init(&tdev->lock);
314 if (tdev->rx_channel) {
315 tdev->rx_buffer = devm_kzalloc(&pdev->dev,
316 MBOX_MAX_MSG_LEN, GFP_KERNEL);
317 if (!tdev->rx_buffer)
321 ret = mbox_test_add_debugfs(pdev, tdev);
325 dev_info(&pdev->dev, "Successfully registered\n");
330 static int mbox_test_remove(struct platform_device *pdev)
332 struct mbox_test_device *tdev = platform_get_drvdata(pdev);
334 debugfs_remove_recursive(root_debugfs_dir);
336 if (tdev->tx_channel)
337 mbox_free_channel(tdev->tx_channel);
338 if (tdev->rx_channel)
339 mbox_free_channel(tdev->rx_channel);
344 static const struct of_device_id mbox_test_match[] = {
345 { .compatible = "mailbox_test" },
349 static struct platform_driver mbox_test_driver = {
351 .name = "mailbox_sti_test",
352 .of_match_table = mbox_test_match,
354 .probe = mbox_test_probe,
355 .remove = mbox_test_remove,
357 module_platform_driver(mbox_test_driver);
359 MODULE_DESCRIPTION("Generic Mailbox Testing Facility");
360 MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org");
361 MODULE_LICENSE("GPL v2");